llS b }Ol.~O: ~D-:l/9"5 BISON lOCkWOOD MEMOitfAL l.JBRARt -FM 6-2 DEPARTMEN·T 0 F THE ARMY FI ELD MANUAL ARTILLERY .SURVEY HEADQUARTERS, DEPARTMENT OF THE ARMY AUGUST 1965 TAGO 10006A * FM 6-2 HE ADQUARTERS DEPARTMENT OF THE ARMY WASHINGTON, D. C., 12 August 1965 ARTILLERY SURVEY Paragra phs PagePART ONE. ARTILLERY SURVEY OPERATIONS AND PLANNING CHAPTER 1. GENERAL -----------------------------------_______ --------------------- 1-8 3 2. FIELD ARTILLERY BATTALION AND BATTERY SURVEY OPERATIONS Section II. I. General ________________________ ~------------------------------------------· Position area survey________________________________________________________ 9-20 5 IlL Connection survey_________________________________________________________ _ 21-25 8 IV. Target area survey_________________________________________________________ 26,27 928-34 10CHAPTER 3. HIGHER ECHELON SURVEYS Section I. Division artillery survey operations__________________________________________ II. Corps artillery survey______________________________________________________ 35-39 1540-53 16 CH APTER 4. OTHER ARTILLERY UNIT SURVEYS Section I. Field artillery group surveys ------------------------------------------------ II. Air defense artillery surveys ________________________________________________ 54-56 2557-61 25 CHAPTER 5. SURVEY PLANNING Section I. General -------------------------------------------------------------------· II. Steps i n survey planning___________________________________________________ 62-64 28 III. The survey order__________________________________________________________ _ 65-69 29 IV. Standing operating procedure ______________________________________________ _ 70-73 30 74, 75 31 PART Two. POSITION DETERMINATION CHAPTER 6. DISTANCE DETERMINATIONSection I. Horizontal taping _________________________________________________________ _ 76-99 32 II. Tell urometer MRA 1/ CW/ MV----------------------------------------------· 100-121 III. 40 Surveying instrument, distance measuring, electronic._________________________ 122-140 58 CHAPTER 7. ANGLE DETERMINATION Section I. Field notes________________________________________________________________ II. Aiming circle M2 ----------------------__________ -------------------------- 141-144 68 III. Theodolite, T16 ___________________________________________________________ _ 1 45-156 71 IV. Theodolite, T2 ____________________________________________________________ _ 157-174 82175-194 92CH APTER 8. TRAVERSE Section I. General __________________________________________________________________Computations______________________________________________________________ _ 195-202 106 II. III. Traverse adjustment_______________________________________________________ _ 203-213 113 IV. Location of traverse errors ________________________________________________ _ 214-218 126219-221 129CHAPTER 9. TRIANGULATION Section I. General__________________________________________________________________ II. Single triangle ___________________________________________________________ _ _ 222-226 132 Ill. Chains of triangles________________________________________________________ _ 227,228 135 IV. Intersection _______________________________________________________________ _ 229,230 142 v. Resection __________________________________________________________________ 231-235 148236-241 148 * This manual supersedes FM 6-2, 7 August 1961 a n d Ch a p t er 3, FM 6-125, 23 April 1963. AGO I0005 A 1 P aragraphs P age TRILATERATION_________________________________________________________ 242-245 154 CHAPTER 10. ~ 11. ALTIMETRY 246-250 156 Section I. General_____________________________________ -------------------------------159 Use of the altimeter_____ -----------------------------------------------------251-257 II. Procedures and computations------------------__________ ------------------__ 258-261 165 III. PART THREE. DIRECTION DETERMINATION CHAPTER 12. ORIENTATION FOR ARTILLERY Introduction___________________ ____________________________________________ _ 262-265 171 Section I. II. Sources of azimuth ________________________________________________________ _ 266-278 171 CHAPTER 13. ASTRONOMIC AZIMUTH General____________________________________________________________________ 279-285 182 Section II. I. Time _____________ _____ ____________________________________________________ 286-291 184 III. Determining fi eld data _______________________________________ __ ______________ _ 292-302 187 Selection of star and method of computation____________________________________ 303-308 193 IV. v. Astronomic computations ___________ -----------------------------------------309-313 200 GYRO AZIMUTH SURVEYING INSTRUMENT CHAPTER 14. General _____________ ___ _____________ ______________________________________ _ 314-316 223 Section I. 317,318 226 II. Operation of the azimuth gyro ----------------------------------------------- III. Use, care, a nd maintenance of the azimuth gyro -----·-------------------------319-322 229 PART FOUR. CONVERTING DATA CONVERSION TO COMMON CONTROL ________ -------------------_______ _ 323-328 236 CHAPTER 15. 16. CONVERSION AND TRANSFORMATION 329-334 241 Section I. Conversion of coordinates------------------_____________ ---------------------335-339 246 II. Transformation_______________________________________ --------------________ QUALIFICATION TESTS FOR SURVEY SPECIALISTS___________________ 340-357 251 CHAPTER 17. REFERENCES ___________ __ _______________________________________________ 263 ~ APPENDIX I. SURVEY SPECIFICATI0 N S___________________________ ________ ____ ________ 266 II. DUTIES OF SURVEY PERSONNEL_____________________________________ _ 269 III. GLOSSARY OF ASTRONOMICAL TERMS --------------------------------271 IV. v. STAR RATE INDEX ------------------------------------------------------273 INDEX ____________ _______________ _______________________________________________________ 281 AGO 10005A PART ONE ARTILLERY SURVEY OPERATIONS AND PLANNING CHAPTER 1 GENERAL 1. Purpose 5. Mission of Artillery Survey This manual is a guide for commanders, surThe mission of artillery s urvey is to providevey officers, and personnel engaged in the cona common grid which will permit the massingduct of artillery surveys. It provides a basis for of fires, the delivery of surprise observed fires,instruction, g uidance, and reference in surveythe delivery of effective unobserved fires, anding principles and procedures. and in the opera the transmission of target data from one unittion and care of surveying instruments. to another . The establishment of a common gridProcedures covering all situations cannot be is a command responsibility. prescribed ; therefore, these instructions should be us ed as a guide in developing suitable tech 6. Fundamental Operations of Survey niques. The material presented herein is ap plicable without modification to both nuclear Survey results are obtained from the fol and nonnuclear warfare. lowing: a. Planning. A thorough plan which includes 2. Scope reconnaissance and gi ves f ull consideration toThis manual discusses the survey personnel the factors affecting survey and conforms toand equipment available to artillery units, the basic essentials contributes t o successful acmeasurement of angles and distances, and the complishment of the s u rvey mission.determination of relative locations on a rectangular grid system. b. Fieldwork. Survey fie ldwork consists of: (1) Measuring distances. 3. References (2) Measuring horizontal and/ or verticalPublications used as references for the angles. manual and those offering further technical in(3) Recording all pertinent data. formation are listed in appendix I. c. Computat'ions. Computations are per 4. Changes and Corrections formed simultaneously with the fieldwork. Users of this manual are encouraged to subKnown data and the fieldwork data are commit recommended changes. or comments to imbined to produce the location and/ or height of prove the manua l. Comments should be keyed a point and/ or the direction of a certain line. to the specific page, paragra ph, and line of thet ext in which the change is recommended. Rea7. Responsibilities of the Corps of Engineers sons should be provided for each comment to a. R esponsi bili ty. The survey responsibilitiesinsure understanding and complete evaluation. of the Corps of Engineers are described in ARComments should be forwarded direct to Com 117-5 and TM 5-231. The Corps of Engineersmandant, U. S. Army Artillery and Missile is responsible for the establishment and extenSchool, ATTN: AKPSIPL, Fort Sill, Okla. sion of basic geodetic control in support of AGO 10 005 A 3 artillery and missile units. Close coordination between engineer and artillery and missile survey units must be maintained because exact methods and procedures for joint operations and boundaries of responsibility can be established only after careful analysis of each survey problem. b. Functions. Corps of Engineers topographic units will (1) Extend all geodetic control required to the area of operation of artillery and missiles, perform all geodetic surveys to an accuracy of third order or higher as required for control of artillery and missile fire and assist, when required, in making astronomic observations to obtain azimuths for the control system of missile launching units. (2) Carry an adequate azimuth from primary (first-or second-order accuracy) geodetic control stations to the area of operations of the missile unit, regardless of the zone of operations, when conditions prevent the unit from ob taining an astronomic azimuth of the required accuracy. (3) When required for artillery and mis t sile units operating outside of the corps zone, extend existing control to the unit area. (4) Furnish existing control data. Whenever practicable, the control data will be furnished on the prescribed mili tary grid. c. Division of Effort. The establishment and extension of control into the corps. area are functions of t he engineer topographic unit. The surveyors of the field artillery target acquisition battalion extend control throughout the corps area and into the division areas. 8. General Responsibilities of Artillery Units Each artillery commander is responsible for seeing that required survey control, consisting of position location and an orienting line of known direction, is furnished to subordinate units as soon as possible. AGO 10005A CHAPTER 2 FIELD ARTILLERY BATTALION AND BATTERY SURVEY OPERATIONS Section I. GENERAL 9. General points should be used as the basis for battalionsurvey operations if survey control points f,or a. This section covers survey operations forall field artillery battalions and batteries. which the battalion have not been established by thehave survey requirements, except field artillery next higher echelon. target acquisition battalions and batteries. Sur b. One or more survey control points whichvey operations for field artillery target acquisi have been established between 1,500 and 2,000tion units are discussed in chapter 3. meters of the battalion installations by the next b. Survey operations are performed by surhigher echelon. These survey control pointsvey personnel in the field artillery battalions. should be used as the basis for battalion surveyoperations. and smaller units to obtain the horizontal and vertical locations of points to be used in deter mining firing data to provide a means of ori12. Use of Assumed Data enting weapons, instruments, radars, and such When neither trig points nor survey controlother equipment or positions requiring this points. exist in the vicinity of the battalion (batcontrol. Survey operations of separate or detery) installations, the battalion (battery) surtached batteries are performed for the same vey officer must establish a point and assumepurpose. data for that point. The assumed data shouldclosely approximate the correct data. This 10. Battalion Survey Control point (and its assumed data) establishes the a. Battalion installations must be located with battalion (battery) grid and is used as therespect to a common grid to permit massing of basis for the battalion (battery) survey operathe fires of two or more battalions. This grid tions. When the next higher echelon establishesshould be the ·grid of the next higher echelon control in the battalion (battery) area, the aswhenever survey control points on that grid are sumed data must be converted to that control.available or when it is desired to mass thefires of more than one battalion. 13. Converting to Grid of NextHigher Echelon b. A battalion survey control point (BnSCP)is a point established by a higher survey chea. The methods of converting survey datalon for the purpose of furnishing survey conare described in chapter 15. Unless the tacticaltrol to the battalion. One or more such points situation causes the commander to decide othermay be established for a battalion. wise, battalion (battery) data are convertedto those of the next higher echelon when datadiffer by 11. Survey Control Points on Gridof Next Higher Echelon (1) Two mils or more in azimuth. Survey control points on the grid of the next (2) Ten meters or more in radial error.higher echelon may be available in the form (3) Two meters or more in height. of b. If the battalion s urvey officer verifies that a. One or more trig points in the vicinity of the battalion survey data is correct, he reports.the battalion installations. When available, trig to his commander and to the survey officer of AGO 10005 A 5 areas where the only existing control is on I the next higher echelon any differences which may exist between the battalion survey data points which are inaccessible. Resection is used ~ to improve map-spotted or assumed data. Anyand the data provided by the next higher eche location determined by resection should belon. checked by a separate determination (pre c. If the next higher echelon converts its surferably traverse or triangulation) at the first vey control to a different grid, the battalion opportunity.must also convert to that grid. 15. Use of Astronomic Observation 14. Survey Methods The problem of converting data to a common Field artillery battalion survey operations grid is greatly simplified if survey personnel may be performed by using any or all of the use the correct grid azimuth to initiate survey artillery s.urvey methods, provided the limitaoperations. True azimuth can be obtained from tions of the selected methods are not exceeded. astronomic observation or by use of the aziA comparison of the different methods is shown muth gyro and converted to grid azimuth. Batbelow. talion survey personnel should be trained to determine grid azimuth by observation of the a. Traverse. For most artillery survey opera sun and stars. They should also be trained intions, traverse (ch. 8) is the best method to use obtaining direction by simultaneous observa because of its simplicity, flexibility, and ac tions.. curacy when performed over open terrain for comparatively short distances. In rough ter 16. Division of Battalion and Battery rain, a tape traverse is time consuming and Survey Operations triangulation or distance-measuring equipment (DME) traverse should be used. a. The survey operations of a field artillery battalion (separate or detached battery) con b. Triangulation. Triangulation (ch. 9) sist of one or more of the following:should be used in rough terrain where taping • (1) Position area survey. is difficult and would require an excessive ex penditure of time. In gently rolling or flat, tree(2) Connection survey. • less terrain, traverse is faster than triangula(3) Target area survey. tion unless distances between stations exceed b. The survey operations performed by a 1,500 to 2,000 meters. If the survey is to cover a large area or if there are consjderable disfield artillery battalion or a separate or de tached field artillery battery depend mainly ontances between stations, triangulation will save three factors as follows:time and personnel. However, a more extensive (1) The type of unit (including assignreconnaissance is required for triangulation ment and mission). than for traverse. (2) The availability of survey control. c. Intersection. Locating the position of a (3) The amount of time available in whichpoint by intersection (ch. 9) is relatively simple to perform initial survey operations. and fas.t. However, this method depends on in tervisibility between the ends of the base line and the unknown point. Intersection must be 17. Sequence of Battalion (Battery) used to locate points beyond friendly frontSurvey Operations lines. When practicable, these locations should Battalion (battery) survey operations are be checked by intersection from more than one performed in the sequence listed below: base. c~. Planning (Including Reconnaissance). A d. R esection. The resection method of locatgeneral discussion of survey planning is contained in chapter 5. To insure maximum ef ing a point (ch. 9) requires, very little field work. Resection normally is used in artillery fectiveness, battalion (bcLtt ery ) survey opera tions should be planned and initiated prior to battalion survey to establish battery centers, the occupat1:on of position. observation posts, or other point locations in f AGO 10005A 6 b. Fieldwork. Fieldwork consists of measuring angles.and distances necessary to determine the survey data required to establish survey stations. The assignment of I:>€rsonnel to accomplish the required fieldwork is determined by the number of surveying parties available and the unit SOP. c. Computations. Each survey computation must be performed by two computers working independently and, when possible, be checked with a slide rule by the chief of party. When possible, survey computations should be performed concurrently with the determination of field data. This will insure that errors ctre det ected at the earliest possible time and will facilitate the early us e of a survey ed firing chctrt. d. Dissemination of Data. After the survey data have been determined, the battalion survey personnel furnish the computed data to the fire direction center for preparation of the firing chart. In the case of missile battalions, the data is used in the computer. 18. Survey Operations of Searchlight Batteries When suitable maps are not available, survey operations are performed by personnel of searchlight batteries for the purpose of determining orienting data for the searchlights. The survey operations performed are those necessary to establish the grid coordinates. and height of each searchlight. In addition, a grid azimuth for directional orientation of the searchlights must be established. 19. Survey of Alternate Positions Survey operations for alternate positions should be performed as soon as survey operations are completed for primary positions. The requirements for alternate positions are identical with the requirements for primary positions. 20. Limited Time Survey Battalion (battery) survey personnel must provide the best possible data for construction of the firing chart and the best means of orienting weapons in the time available. When time is a consideration, the survey officer must plan and accomplish the survey operations necessary to furnish the fire direction officer with an improved firing chart. The extent of the survey conducted and the methods employed will ·depend primarily on the time available. The procedures used for accomplishing the division of operations may be any combination of the fol lowing: a. Posi tion Area Surve y. (1) Map-spot the battery centers. Determine direction by compass, declinated aiming circle, astronomic observation, or azimuth gyro, as time and weather permit. (2) Map-spot the center battery, and locate the flank batteries by open traverse. Determine a starting direction as in (1) above. (3) Map-spot a battalion SCP and locate the batteries by open traverse. Determine starting direction as in (1) above. b. Connection Survey. ( 1) Establish control by firing. (2) Use a map for the connection survey. Transmit direction by simultaneous observation '(weather permitting) or by directional traverse. c. Tar,q et Area Survey. (1) Target area base. (a) Map-spot 01 and traverse to locate 02. (b) Map-spot a target area survey control point and traverse to locate 01 and 02. (c) Map-spot a target area survey control point and intersect 01 and 02 from an auxiliary base. (2) Critical points. (a) Map-spot all critical points. (b) Perform intersection from a target area base. AGO 10005A Section II. POSITION AREA SURVEY may select the location of the orienting station 21. General if the battalion (battery) SOP so states. a. Survey control is required in the position area of each firing battery. The battery center d. Registration point-A point in the target is the point surveyed for cannon batteries, area the location of which is known on the ground and on the firing chart (FM 6-40). whereas the launcher position is the point surveyed for rockets and missiles. Position area e. Direction of fire-A base direction of fire survey is performed by battalion (separate or for all weapons of the firing unit. It may be the detached battery) survey personnel for the pur computed azimuth from the battery center to pose of-the registration point or a selected azimuth of (1) Locating weapons positions and rafire assigned to the unit by the battalion comdars. mander or other authority. (2) Providing means for orienting weapf. Orienting angle-The horizontal, clockons and radars. wise angle from the direction of fire to the orienting line. The orienting angle determined by b. The position area survey for field artillery survey personnel is computed by subtracting thecannon and missile units is usually performed azimuth of the desired line of fire from the azito a minimum prescribed accuracy of fifth-order muth of the orienting line, adding 6,400 mils to (1:1,000); however, when the TOE of the unit the azimuth of the orienting line if necessary.authorizes the aiming circle M2 as the instru ment for survey, the position survey is perg. Radar orienting point-A point used to formed to a minimum prescribed accuracy of orient the radar. The radar operating point for field artillery radar sets is established in a di 1:500. rection as nearly in the center of sector of search of the radar as possible. The radar offi 22. Terms Used in Conjunction With cer furnishes to the survey officer the approxiPosition Area Survey mate azimuth on which the radar orienting The following terms are used in conjunction point should be established.with position area surveys: 23. Method of Performing Position n. Battery center-A point on the ground at Area Survey the approximate geometric center of the weap ons position. The battery center is the chart loAny method or combination of methods listed cation of the battery (FM 6-40). The location in paragraph 14 may be used to perform the of the battery center is designated by the batposition area survey. The method most comtery commander or battery executive. The surmonly used is traverse. The position area survey vey officer may select a tentative battery center is initiated at a survey control point, the point if the battalion (battery) SOP so states. that establishes the unit grid, or a station established by the connection survey. The survey b. O'rienting line-A line of known direction is closed on the starting point or on a station established near the firing battery, which serves established to an accuracy equal to or greater as a basis for laying for direction (FM 6-40). than that of the survey being performed. (The azimuth of the orienting line (OL) is included in the data reported to the fire direction 24. Survey for Weapons Positions center.) n. In surveying a weapons position, an orienting station, from which all battery weapons c. Orienting station-A point on the orientshould be visible, is established near the batterying line, established on the ground, at which the center. Normally, this point is used as one endbattery executive sets up an aiming circle to lay the pieces (FlVI 6-40). The location of the oriof the orienting line, and the traverse leg used to establish the station is used as the orienting enting station is designated by the battery comline. This makes the orienting line a leg of themander or battery executive. The survey officer AGO 10005A 8 • closed traverse, thus permitting the detection of 25. Survey for Radar an error in the OL should the traverse not close in azimuth. If a traverse leg cannot be One countermortar radar is organic to eachused as the orienting line, a prominent terrain divisional direct support artillery battalion. object at least 300 meters away should be used The coordinates and height of the radar posias the end of the OL. The azimuth of this line tion and a line of known direction are requiredis determined by measuring, at the orienting to properly orient the system. It may be necesstation, the angle from the last traverse station sary to determine the same data for the surveil to the selected point. For all night operations, lance radar of division artillery should it be the orienting line must be prepared for orienta located near the battalion position area. tion of the weapons by placing a stake equipped a. Data for the radars are determined in thewith a night lighting device on the orienting same manner as data for weapons positions. An line approximately 100 meters from the orientorienting azimuth from the radar positioning ing station. When an intermediate point cannotbe established on the orienting line, an alternate stake to an orienting point must be determined. orienting line is established on which the night b. The height of the radar antenna also mustorienting point can be set up. be computed. Height is determined by measuring the distance from the ground to the para b. The coordinates and height of the battery bola, to the nearest 0.1 meter, by means of acenter are determined by establishing a traverse steel tape. The distance measured is added tostation over the battery center or by establishthe computed ground height.ing an offset leg (an open traverse leg) from~he orienting station to the battery center. Section Ill. CONNECTION SURVEY 26. General SCP it may close on that SCP or on any other a. Connection survey is that part of the surSCP established to an accuracy of 1:1,000 orvey operation performed by battalion (separate greater on the same grid as the Bn SCP. Whenbattery) survey personnel for the purpose of the connection survey is initiated at the pointthat establishes the battalion grid (i.e., when placing the target area survey and the position area survey on a common grid. data for the starting point is assumed) , it mustclose on the starting point. This point does not b. Connection surveys are performed to fifthbecome the Bn SCP unless survey control for order accuracy. the point is established by the next higher echelon of survey. 27. Methods of Performing Connection Survey b. A secondary requirement for connectionsurvey may include providing control for thea.. A closed traverse normally is used to permortars within the supported brigade or forform the connection survey, although triangularadars and other target acquisition devices lotion may be used when the terrain is unsuitable cated within the area of operation. Control isfor traver2e. The connection survey is used to extended to these installations as time permits.establish a target area survey control point or The requirements of the artillery battalion one or more of the target area base observation takes priority in these instances. pests from which target area base survey opera tions are initiated. The connection survey is c. Since missile units are normally employed usually initiated at a station on the position in a general support or reinforcing role, they normally receive target data from higher headarea survey. The station may be a Bn SCP or quarters or the supported unit. the point which establishes the battalion grid. Therefore, these units do not perform target area or conWhen the connection survey is initiated at a Bn nection survey. AGO 10005 A 9 Section IV. TARGET AREA SURVEY t'ion base must be sufficient to provide a mini 28. General mum angle of intersection of 150 mils at any Target area survey is that part of the survey critical point in the target area. The consistent operation performed by battalion (detached accuracy that can be obtained from the locabattery) survey personnel for the purpose of tion of points with angles of this minimum size establishing the target area base and locating is approximately 1:200. critical points and targets in the target area; i.e., registration point(s) and restitution b. The location of each critical point should be checked from at least two intersection bases. points. As soon as possible, additional observation posts should be selected to provide this check. 29. Terms Used in Conjunction With Besides providing the check, the additional obTarget Area Survey servation posts should provide observation into a. Target Area Base. A target area base conthe unit's zone of action, especially into those sists of two or more observation posts which areas which are not visible from the observaare used to locate the critical points in the tartion posts originally selected. get area and/ or targets of opportunity and to conduct center-of-impact and high-burst reg31. Methods of Performing Target Area Base istrations. When there are more than two obSurvey servation posts, any two of them can be used to a. The method of survey normally used by form an intersection base. the survey party in the field artillery battalion to perform the target area base survey is a b. Azimuth Mrl1'k for Tct?·g et Area Obse?·v a closed traverse. If the enemy situation is suchtion Post. An azimuth mark is a reference point that traversing to an OP would disclose its poused to orient the instrument at each observasition, and if the terrain allows, triangulationtion post. The azimuth to the azimuth mark is used. On some occasions, it may be necessarymay be determined by using the back-azimuth to locate the OP by intersection or offset from aof a traverse or intersection leg used to locate traverse station in the vicinity of the OP. Thethe observation post. The adjacent observation OP's are located to fifth-order accuracy. post (when OP's are intervisible) may also be used as an azimuth mark. An auxiliary or inb. In issuing the survey order, the survey oftermediate orienting point should be estabficer designates which of the survey parties is lished for night operations. to perform the target area base survey. The specific location of each OP may also be desig 30. Selection of Observation Posts nated or an approximate location may be given and the specific location left to the discretion of a. Initially, two or more observation posts the chief surveyor or chief of party. The locaare established at points from which the critition of a target area survey control point is cal points in the target area are visible. If posgiven. If one OP is located as part of the consible, the distance between any two observation nection s urvey, it may be designated as the tarposts should be sufficient to insure a minimum get area survey control point.angle of intersection of 300 mils at any of the c. The observation posts are designated 01,critical points. These minimum angles at the critical points in the target area are necessary 02, etc. 01 is considered the control OP and is to insure results that approach the accuracies plotted on the firing chart. 01 may be on the right or left. 01 is always that OP requiringprescribed for target area survey. If the obserthe least amount of fieldwork to establish its lovation posts of the target area base cannot be cation since less directional accuracy is lost located sufficiently far apart to provide a mini mum angle or intersection of 300 mils, they through angular measurements when the num should be located as far apart as possible. In ber of main scheme angles is held to a mim any case, the distance between observation mum. Examples of target area base surveys posts that are used as the ends of an intersec-are shown in figure 1. AGO 10005 A 10 COMPUTED AZIMUTH AND DISTANCE ITASCPl ---------~------- TARGET AREA PARTY 0 01 ESTABLISHED BY CONNECTION SUilVEY PARTY CONNECTION SURVEY 111000 lOP'S NON INTERVISIBLEl COMPUTED LENGTH 0 OP'S ESTABLISHED BY TAR GET AREA PARTY 1/1000 l OP'S INTERVISIBLEl "---- CONNECTION SU~EY--- Figure 1. Target a1·ea base survey. 32. Method of Performing Target Area b. If the observation posts are intervisible,Survey the interior horizontal angles are measured a. Intersection must be used to perform the (1, fig. 2). If the observation posts are not intervisible, the angles at the ends of the base target area survey. The length of each intersec must be determined by comparing the azimuth tion base of the target area base is obtained by computation from the coordinates of the two of the base with the azimuth from each obserobservation posts that establish the base. (The vation post to the point being located (2, fig.length of the base may be determined by 2). The azimuth of the line from each observadouble-taping to a comparative accuracy of tion post to the critical point is determined by1:3,000 when the base is located in an area not measuring the horizontal angle, at the obserunder direct observation of the enemy.) If the vation post, from the established azimuth mark ' observation posts are intervisible, the azimuth (orienting station for night operations) to the of the base is determined by measuring the point in the target area. When the criticalpoint does not present a clearly defined vertical horizontal angle at an observation post from line and cannot be accurately bisected, the the rear station to the observation post at the horizontal angles are measured by using a spe other end of the base. If the observation posts cial technique of pointing. Pointings are made are not intervisible, the azimuth of the base is by placing the vertical line in the reticle on the ~ determined by computation, using the coordileft edge of the object in measuring the first ' nates of the ends of the base. value of the angle and by placing the vertical AGO 10005A 11 ner in which they are determined by triangula RestitutionRegistration Point Point(s) tion (chap 9). ./1 t /f e. The party performing the target area / / I survey furnishes the location of the registration point(s) to the party performing the position area survey for computation of the orienting angle(s). f. The locations of critical points determined from the target area base should be checked by Ends of Base lntervisible establishing a second intersection base. A second intersection base can be established by using a thir d observation post and either of the two initial observation posts. 33. Center-of-Impact and High-Burst Registrations In either a center-of-impact (CI) or highburst (HB) registration, a group of rounds is fired in order to determine corrections to firing Angle= Azimuth of Bosedata. The location of the center of the group of Azimuth to rounds must be determined and then plotted on the firing chart. One method commonly used to determine the location of the burst center is by a computed intersection from the 01-02 target STATIONS IN CONNECTION SURVEY area base. This method requires that the bursts be observed by both 01 and 02; therefore, pri Ends of Base Not lntervisible mary consideration must be given to the topography of the impact area and the location of Figw ·e 2. Target area survey. each observation post. For a high-burst registration, which is conducted with time fuze toline in the reticle on the right edge of the obobtain airbursts, these considerations are nor ject in measuring the second value of the angle, mally of lesser importance than for a center-of accumulating these angles on the aiming circle. impact registration. For a center-of-impact The angles are meaned. The mean angle obis em tained with this method must be verified by de registration, for which impact fuze t ermining at least one more mean angle by ployed, the burst area should be free of trees, using the same technique. The accumulated buildings, sharp ravines, etc. A gentle forward slope, free of all vegetation, or the center of a value of the first set (one pointing to each edge lake is ideal. When a center-of-impact or high of the object) should agree with the accumuburst registration is conducted, the location of lated value of the second set within 1 mil. The means of both sets are then meaned to provide each observer and t he desired point of burst are known at the fire direction center. The fire an angle to the point to the nearest 0.1 mil. direction center deter mines and furnishes to c. Vertical angles are measured to the lowest each obser ver the azimuth and vertical angle to visible point on the object. the expected point of burst. The message to the • observers from the fi re direction center in d. The distance from either end of the inter section base to each critical point is computed cludes instructions to the observer at 01 to by using the base length determined in a measure the vertical angle to each burst. A typical message to the observers from the fire above and the angles determined by direct direction center is as follows: "Observe high measurement (1, fig. 2) or by comparison of burst (or center of impact). 01 azimuth 1049, azimuths (2, fig. 2). The coordinates and height vertical angle + 15, measure the vertical angle. ~ of each point are determined in the same man- AGO 10005A • 12 • 02 azimuth 768, v ertical angle + 12. Report 34. Computation of Center of Impact andwhen ready to observe." Each observer orients High Bursthis instrument on the azimuth and verticalangle given for his OP and reports to the FDC The target area base may be used as a tool in when ready to observe. One round at a time is performing a center-of-impact or high-burstfired, and "On the way" is given to the obregistration. Normally the computations assoservers for each round. The first round fired is ciated with the instrument readings to deternormally an orienting round, and each observer mine the location of the center of impact ororients the center of the reticle of his instruhigh burst are performed by the fire directic,}nment on the burst and records the scale readpersonnel. A knowledge of the manner in whichings of his instrument corresponding to the these computations are performed is of valuenew position of the telescope. After the obto the survey personnel operating the targetserver orients his instrument on the orienting area base. The computations are normallyround, he normally should not have to change made on DA Form 6-55.the orientation during the rest of the registra Example: tion. One rou nd at a time is fired until sixusable rounds have been obtained (excluding Given: Coordinates of 01: ( 561599.8-3839123.3) Azimuth 01 to 02: erratic rounds and rounds observed by only Distance 01 to 02: 3,960 mils 843 meters one observer). After the instrument has been Height 01 : 453 meters oriented on the orienting round, the deviation observed for each burst is combined with the Instrument ?"eadings of usable rounds reference reading on the instrument scales to Azimuth 01 Vertical ~ Azimuth 02 derive the azimuth to the burst. The same Round (mils) 01 (mila) (mils) general procedure is used to measure the verti1 5,710 + 24 5,959I cal angle. Both observers report azimuth read2 5,710 + 28 5,950 ings to the fire direction center after each 3 5,708 + 29 5,953 4 5,705 round, but only the observer at 01 reports the +25 5,951 5 5,715 + 23 5,952 vertical angle. At the fire direction center, the 6 5,713 +26 5,955 instrument readings from 01 and 02 for the Requirem ent: Solve for the azimuth and distance from - six usable rounds are used to determine the 01 to the center of the high burst and the height of mean point of burst for the registration. the high burst, using DA Form 6-55 (fig. 3). AGO 10005A 13 HIGH BURST (CENTER OF IMPACT) REGISTRATION (FM6-40) COMPUTATION OF HB (CI) LOCATION Data F~red Chg IOf IFS loE Observer Readings Interior Angles Rd 01 02 01 on Left 01 on Right Nr Az VA Az 1\ I I 5710 ~4 5959 Az~02 / Az 01-HB-1€-+t 5710 +6400 if 2 +64~~ necessary 5710 28 5950 necesso / 3 5708 29 5953 Toto I '\ / 5710 Total -Az 01-02 4 5705 125 5951 -Az 01-HB~ I 3960 5 2~ 5952 40101 ) 40101 1750 5715 6 Az 02•HB !cf \ 760 Az 02-+01 5713 26 5955 +6400 if+6400 it,/ 7 nece ssory, necessary 6400 1\ 8 Total j 1\ Total 7160 9 -A/o2•01 1\ -Az 02-HB(Cil 5953 10 f.-or 02 \ 4-ot 02 1207 34261 15~ 35720 Toto I 5953 Average 5710 26 Bear in g= Bear ing : Az 01-HB-- Apex Angle 6400 -Az _A_z_ Bear ingHB 4-ot 01 1750 dEt dE-~ 6400 dN+ dNt +4o1 02 207243 5710 Sum 3057 mnI Bearing 1750 3200 dE-dE+1207.¢ 01 -Sum 3057 dN-dN- Beorong : Beor1ng : 02 s4'?>""· Apex Angle 243 Az -3200 3200-Az N690W Distance 01 HB (Cil Log conversion fo etor, meters to yards Log bose 01-02 : 9251828 odd 0.038863 843M. 2 +Log sin4-at 021207Jri' 9 :966 1840 Sum 2 1892 1668 -Log sin Apex Angle 243Jl'( 9 1373 1479 diff =Log dis! 01-HB(CI) 3 1519 1189 • Dete rmire the distance 01-HB (CI) to check computelions of dE, dNa dH by polar plotting from 01 on Dist 01-HB-+€** B305.1 M overage az imuth an d computed dis! Log of dE, dN, ond dH Log dist I Log dist Log dis! 01-HB(CI) 3 1519 1189 01-HB (Cil 3!519 1189 01-HB (CI) 3 : 519 ! 189 Log sin Log Ton Bearing 9 ! 891 1650 Vert4- Sum= Sum : Sum= Bear in g 9 i 797i Ill Log cos a:407 :068 1 1926 1257 Log dE 3 1316 1300 Log ON 3 1410 i839 Log dH Coordinates of 01 E 1561 J599l8N 3 :839'12313 ~ 453l 0 I I~E 2 !0711El~N : 2 !575!4 ~H I 84l4I I I J'J i I Location of HB (Cil E 1 5591 528l~ N 3:941 :5991 1 H 537l4 COMPUTATION OF GFT SETTING Of carr All HB(CI ) -~ Char~ -- I I -- :---De{W " rlt Ronge __M S it~--GFT rhnr e__Lot __-All Btry VI/H Range --Eleva 1 .lime VI--~Adj Elev (HB or Cl Rg) (T~ FigU?·e 3. High burst r egistration computation (DA Form 6-55). AGO 10005A 14 CHAPTER 3 HIGHER ECHELON SURVEYS Section I. DIVISION ARTILLERY SURVEY OPERATIONS 35. General l€ry headquarters. The survey information cen a. Survey operations are performed by surter is normally located in the operation centervey personnel of division artillery h€adquarat the division artillery command post.ters battery for the purpose of placing the field b. The survey information map shows theartillery units organic, assigned, or attached locations of survey control points and trigto the division on a common grid. points and the schem€s of all surveys per b. Division artillery surveys are executed to formed by the division artillery survey section.a prescribed accuracy of fourth-order. SpecifiThe surv€y information file consists of the trigcations and techniques for fourth-order surv€y lists prepared and is.sued by the Corps of Enare given in appendix II. gineers, the trig lists prepar€d by the fieldartillery target acquisition battalion, and data 36. Division Artillery Survey Officer for each control point established by divisionartillery survey op€rations. The data for each a. A survey officer is assigned to the division artillery staff. The division artillery survey control point established by division artillery officer plans and supervises the division artilare recorded on DA Form 6-5 (Record-Survey Control Point) (figs. 4 and 5). lery survey operations. He advises the com mander and appropriate staff officers on matters pertaining to survey. He coordinates 38. Division Artillery Survey Control the survey operations of the field artillery bat a. Division artillery battalions., batteries, andtalions (separate batteries) within the division. other division installations that ·require survey b. Th€ division artillery survey officer should control should be located with respect to a commaintain close liaison with the corps artillery mon grid. This grid should be the corps gridsurvey officer to obtain data for survey control whenever control points on th€ corps grid arepoints which have been established in the diviavailable. Control points on the corps grid aresion area by the target acqnis;+i on battalion. normally available in the form of trig pointsThe use of th€se points can save time and can and survey control points for which data areeliminate unnecessary duplication of survey known with respect to the univ€rsal transverseoperations. H€ can also obtain data for points mercator (U'FM) grid or universal polar stereoestablished in the vicinity of the t-arget area; gr aphic (UPS) grid for the area of operations.the data for these points can b"e1:1sed by the b. When neither survey control points norbattalion survey parties in performing target trig points are available in the division area, ar€a surveys. the division artillery survey officer establishesa point and assumes data for it. This point 37. Division Artillery Survey Information establishes the division grid which is used as Center the basis for division artillery survey opera a. A file of survey information and a s.urvey tions. When the assumed data for the pointinformation map are maintained in a survey differ from the data subsequently establish€dinformation center (SIC) at the division artilby the field artillery target acquisition battal- AGO 10005 A 15 ion of corps artillery, the division artillery points for which battalion survey parties should data are converted to the corps grid (ch. 15). determine survey data in order to check the accuracy of the surveys being performed by Although during the initial stages of an opera tion, it is not necessary for division artillery the battalions. to convert assumed azimuth to the corps azic. Normally, division artillery survey operamuth if it differs. by 0.3 mil (1 minute) or less, tions are performed by the division artillery it should be converted as soon as practicable. Iri survey section. When the time available to perany case, coordinates and height should be conform division a·rtillery survey is limited, the verted to the corps grid. division artillery commander may direct batta1ions of the artillery with the division to as 39. Division Artillery Survey Operations sist in performing the surveys necessary to establish the division artillery grid after they a. Division artillery survey operations should have completed their battalion survey operaprovide the best possible data at the earliest tions. When this is necessary, the division arpracticable time. Any of the artillery survey tillery survey section should, at the. first methods may be used to perform the surveys. opportunity, conduct another survey of those In areas where survey control points are not installations surveyed by the battalions. available in the vicinity of the battalions, com d. When a target acquisition battery is atmon direction can be provided by astronomic tached to a division artillery, the survey parties or gyroscopic observations. or obtained by of the battery may perform part of the divisionsimultaneous observations. artillery survey operations. The division artillery survey officer, in conjunction with the tar b. In addition to providing survey control get acquisition battery commander, plans and points for battalions and/ or batteries, the supervises the coordinated survey operations. division artillery survey officer may designate Section II. CORPS ARTILLERY SURVEY F ATAB survey operations are the collection, 40. General evaluation, and dissemination of survey infor a. Corps artillery survey operations are permation for all surveys executed in the corps formed by the field artillery target acquisition area to a prescribed accuracy of fourth-order battalion (FATAB) assigned to each corps aror greater. Surveys performed by the target tillery. The battalion commander of the field acquisition battalion are executed to a preartillery target acquisition battalion is the scribed accuracy of fourth-order. corps artillery survey officer. The target acquisition battalion survey officer is responsible to 41 . Survey Information Center the battalion commander for planning and supervising the battalion survey operations. a. A survey information center is established at corps artillery and maintained by the sur b. Provisions exist for the attachment of vey personnel of headquarters. battery of the officers of the U. S. Coast and Geodetic SurtaTget acquisition battalion. It is usually lovey to the FATAB in time of war. These cated in the vicinity of the corps artillery fire officers will fill positions as directed. direction center. The SIC is an agency for collecting, evaluating, and disseminating surveyc. Survey operations are performed by surdata. The dissemination is accomplished byvey personnel of the field artillery target acquipreparing and distributing trig lists and bysition battalion for the purpose of placing the furnishing survey information to personnel offield artillery with the corps (and other units other units upon request. Unless the battalion Tequiring survey control) on a common grid and of locating the target acquisition battalion commander directs otherwise, all survey information is disseminated in writing onlty through installations, which include flash, sound, and the survey information center. radar installations. Also included in the AGO 10005A 16 5"r,t 11<'3''-I 441 3 I P3S" I 7t~'f I .If~ I 13S"'f 1-, I I I I ®FT YO EAST I NG NORTH I NG HEIGHT • ~ _. AREA ~ ~ 0~ ..., ~ ~ ~ ,_z ~ .. 4 "" ~ OTHER FT YO HlME OR DES IGNATI ON (A~ tiK) EAST I •G NORTHING HEIGH T c:::J MEASURE D .. "" "' :c HOW 1-- DE TERM I NED ~"' ..... OTHER At MKS VISIBLE FROM SC P REPLACES DA FOR M,6-5 , l OCT 52, WHICH WILl BE USED UNT 1l EX HAU STED. RECORO -SURVEY CONTROL POINT Figure 4. Entries made on the j1·ont of DA Form 6-5. b. Files of all fourth-order or higher survey shows the locations of all existing trig pointscontrol existing in the corps area and files of and survey control points and the schemes oftie-in points established in adjacent corps areas completed surveys. Overlays to the map showby the target acquisition battalions or division the survey operations that are currently beinga-rtilleries are maintained in the survey infor performed by the target acquisition battalionmation center. These files consist of trig lists and division artilleries with the corps. Thepublished by higher headquarters (including overlays also show the tactical situation, thetrig lists prepared by the Corps of Engineers), location of each installation of the target acquitrig lists publi1?hed by field artillery target sition battalion, present and proposed artilleryacquisition battalions operating in the adjacent positions, and proposed survey plans.corps areas, and data for each survey controlpoint established by the target acquisition batd. Time accurate to 0.2 second is maintainedtalion survey parties and by the parties of the for the use of FATAB survey parties and subdivision artilleries with the corps. The data for ordinate units when making astronomic obeach survey control point established by the servations. target acquisition battalion and by division e. In addition to performing the functionsartillery headquarters are recorded on DA discussed in a through d above, survey inforForm 6-5 (figs. 4 and 5) . mation center personnel assist in the survey c. An operations map is maintained in the operations of the target acquisition battalion by survey information center. The operations map computing and checking data. Computations AGO 10005A 17 SC P DESC RIPT IO N ( Continued) SKET CI-I J L_ _j L~-------------~ AUSTIN RD I -DooDl~l~-------------~ 1 c::J '~' ~30lfl 130781 ItI BECK Ai MK DESCR I PT IO N ( Continued) POINT TO !3£ 3/GIITED ON DATE (IE5C~ IPTIO"l PREP ARED AY DEscR IPT i o N c HECKE D sv L£o I Ou. l?~o .ToN£5 Figure 5. Ent1·i es made on the back of DA Fonn 6-5. ' (1) Plans the corps artillery survey. and checks performed by the survey informa tion center personnel include the following: (2) Coordinates the survey of the target (1) Checks of field records and computaacquisition battalion with all other tions of field parties. artillery units in the corps area. (2) Ad]ustment of traverses. (3) Maintains liaison with, and obtains control data from, the topographic (3) Conversion of survey data to the corps engineer unit operating with thegrid when survey operations have been corps. performed with assumed data. (4) Establishes the survey information (4) Transformation of coordinates and center at corps artillery. grid azimuths. (5) Conversion of coordinates (geographic b. The battalion survey officer is assigned to to grid and/ or grid to geographic). the battalion staff. The battalion survey' officer plans and supervises the battalion survey operations, advises the battalion commander 42. Field Artillery Target Acquisition and the staff on matters pertaining to survey, Battalion Survey Personnel and performs the coordination of the surveya. The field artillery target acquisition battaloperations of all field artillery units operating ion commander is the corps artillery survey in the corps are~;~-. An assistant battalion survey officer. Under the direction of the corps artilofficer, the survey platoon commander in head lery commander and assisted by the battalion survey officer, the corps artillery survey offiquarters battery, performs duties as directed by the battalion survey officer. cer- AGO 10005A 18 c. A warrant officer, assigned to headquar1,500 to 2,000 meters of any possible artilleryters battery, supervises the operations of the position in the corps area.survey information center. d. The battalion survey officer designates to d. A survey platoon is assigned to each bateach platoon commander the areas requiringtery of the target acquisition . battalion. The survey control points. These survey controlplatoon commander is the survey officer of the points are established for later extension ofbattery. He plans and supervises the survey control and for checking surveys.operations of the survey platoon and advises ·e. Survey operations of the target acquisition the battery commander on matters pertaining battalion are continuous.. The amount of survey to survey. performed by the target acquisition battalionin any area of operations depends on the length 43. Coordination and Supervision of of time that the corps remains in the area. In Battalion Surveys by the Battalion rapidly moving situations, the target acquisi Survey Officer tion battalion may be able to complete only theThe target acquisition battalion survey offiinitial phase of survey operations. If the corpscer normally is authorized by the battalion remains in one area for an extended period ofcommander to issue instructions on matters time, the target acquisition battalion conductsconcerning survey operations directly to the extensive survey operations.batteries. The relations between the battalionsurvey officer and the battery survey officers 45. Use of Assumed Datain issuing and receiving instructions are simi When possible, survey platoons initiate theirlar to the relations between the battalion fire survey operations at survey control points (ordirection officer in a howitzer or gun battalion trig points). If no survey control points existand the battery executive officers. The battery survey officers must keep their battery comin the area, the battalion survey officer designates a point and furnishes assumed data for manders informed of the survey operations that tll.c:'lt point. The assumed data should approxithey have been instructed to perform. They mate the correct grid data as closely as posmust also keep their battery commanders insible. The surveys of all of the platoons areformed of the a·reas in which the battery sur vey platoon will be operating and the progress then tied to this point, thus establishing acommon grid and azimuth. Assumed data are of the survey operations. converted to known data as soon as practicable. 44. Field Artillery Target Acquisition 46. AzimuthsBattalion Survey Operations a. Target acquisition battalion survey operaAzimuths at all points of the battalion survey tions are conducted in two phases-an in itial should be correct grid azimuths. Correct grid phase and an expansi on phase. azimuth can normally be established by astronomic observation or by use of the azimuth b. The survey operations conducted during gyro. When two intervisible survey controlthe initial phase consist of those surveys neces points (based on correct grid data) or trigsary to establish a survey control point for each points exist, correct grid azimuth can be ob division artillery and each corps artillery bat tained from these points. If the correct gridtalion (and other points as directed by the batazimuth between the points is not known, ittalion commander) and those necessary to es. can be computed by using the grid coordinates.tablish survey control for the installations of the points.organic to the target acquisition battalion thatrequire survey control. 47. Survey Control Points c. The survey operations conducted during Survey parties of the battalion establish surthe expansion phase consist of the surveys vey control points approximately every 1,500necessary to place s urvey control points within to 2,000 meters along the routes of their sur- AGO 10005 A 19 veys. A station is established for each division for installations. of other units. The commander artillery, for each corps artillery battalion, and of the survey platoon plans the initial phase for each point from which target acquisition operations of the platoon by first considering battery installations are located. A station is the operations necessary to locate the target acquisition battalion installations. He thenalso established at each point designated for modifies this plan, as necessary, to provide surlater extens.ion of control and for checking sur veys. Each of these survey control points is vey control for the installations of other units. marked by a hub and a reference stake (fig. If priorities have been established by the battalion survey officer, the platoon commander 45). An azimuth for each survey control point must incorporate them in his survey plan. is established either to an azimuth marker or to an adjacent survey control point. A description of each survey control point is prepared 49. Target Acquisition Survey Platoon on DA Form 6-5 and forwarded to the s.urvey Operations During the Initial Phase information center for filing. a. The survey operations performed by a target acquisition survey platoon during the initial 48. Planning Battery Survey Operations phase are those necessary to locate the target The points for which survey control must be acquisition battery installations that require survey control and to provide a survey control established by the survey platoon of each bat tery of the target acquisition battalion fall into point for the division artillery and for each two general categories-those for installations corps artillery battalion in the platoon's area of the target acquisition battalion and those of responsibility. OP 4/\ 7'\". 0 p 3/\ I '" /=r. OP~ M6 ® ••••) '\, / I \ OP 26 I I ' ' • • M5@. • • / I \ /I ' I I ~/ \ ./ "-I ' • II~·-· R2~~. M4®••• I \ / / ', M3~• • • ~/___)_•-• -~~· BN SCP "'· )( ••• )( ~ M2®•• / R l ~ • : I L!.._J40 • ®••/ • •• Ml~ TA BTRY SCP BN SCP @59 LEGEND PARTY I ____(TELL.) PARTY 2 -•-•-•-•- PARTY 3 • • • • • • • • • • • Figure 6. Target acquisition platoon sw·vey during the initial phase. AGO I0005A 2o 4 / ,- _. / I -....~--~--/ ' I I I I, __ , XXX xxxx-- .A FLASH OP • CRITICAL TRAVERSE STATION ---..-SOUND BASE ...-_-;. •BATTALION POSITION ~HQS BTRY SURVEY ---LETTER BTRY SURVEY Figure 7. Target acquisition battalion survey operations during the initial phase. b. All or part of the survey platoon operations are frequently started with assumed coordinates and height. For example, if survey control points do not exist in the vicinity of the selected sound base microphones, the sound base survey (and the establishment of any survey control points along the line of the sound base) is frequently performed by two parties starting at a point near the center of the sound base with assumed data, while a third party extends survey control to the starting point. c. Figure 6 shows an example of the survey operations conducted by a survey platoon during the initial phase. Figure 7 shows an example of the survey operations conducted by a target acquisition battalion during the initial AGO 10005 A phase. The critical traverse stations shown in black are those at which a traverse is initiated or closed. d. The initial phase operations include those actions necessary to close all traverses, to check all intersected and resected points, to establish a declination station in the division area, and to determine the locations of survey control points that were established by the target acquisition battery survey platoons operating in the adjacent division areas. The initial phase of the battalion survey operations is considered complete when these operations have been performed by the survey platoons of each of the target acquisition batteries. t , . 'Y"·re 8. T arget acquisition battalion survey operations during the expansion phase. I c. Figure 8 shows an example of the survey 50. Survey Operations During the Expansion operations of a target acquisition battalion Phase during the expansion phase. a. Survey operations of the target acquisition battalion during the expansion phase consist of establishing, usually by triangulation or DME 51. Extension of Survey Control From Rear traverse, a basic net throughout the corps area. Areas From stations of the basic net, control is When the only existing survey control is aextended to provide survey control through considerable distance to the rear of the corpsout the corps area. The ultimate goal is a sur area, control should, if possible, be extendedvey control point within 1,500 to 2.000 meters to the corps area by engineer topographic of every possible artillery position. This goal units. When this is not possible, the ta-rget acis accomplished to the extent permitted by the quisition battalion may be required to extendtime available. the control. This normally is accomplished by b. During the expansion phase, the survey the use of DME traverse schemes. This extenplatoons of the battalion are assigned tasks by sion of control may be initiated either during the battalion survey officer as necessary to acthe initial phase or during the expansion phase, complish the required survey operations. The depending on the situation. When it is initiated survey platoon of each battery should be asduring the initial phase, it is usually accomsigned tasks in a·reas as near as possible to its plished by the headquarters battery survey battery area to facilitate operations. platoon. The battery survey platoons may be AGO 10005A required to furnish one or more survey parties the sum of the initial circle settingto assist in these operations. (the horizontal circle reading whenthe instrument is pointed at the 52. Survey Control for Sound Ranging rear traverse station) and the comMicrophones puted horizontal angle. As an ex a. The operations necessary to establish surample, assume that the initial circlesetting is 0000.151 mil and that the vey control for sound ranging microphones decomputed horizontal angle is 3,089.422 pend on the type of sound base selected by thesound ranging personnel. When the micromils. The value that must be set onthe horizontal circle is 3,089.573 mils phones are employed in an irregular base, the microphone positions are marked, either with a (0000.151 mil + 3,089.422 mils). stake or with a microphone, by sound ranging (4) A rodman, guided by the instrumentpersonnel. The location of each irregular-base operator sighting through the telemicrophone is determined in the manner used scope of his instrument, emplaces ato locate any other survey station. When the range pole on the line of sight at amicrophones are employed in a regular base, distance approximately equal to thethe coordinates of each microphone are prede computed distance to the microphonetermined on DA Form 6-2, using the distance position. The rodman paces the combetween microphones and the azimuth of the puted distance to the microphone posibase, as furnished by sound ranging personnel tion ; this serves as a check for large(FM 6-122) . Then, points are established on errors in taping ((E) below).the ground at the location of the computed co (5) A taping team then tapes the com ordinates by following the procedure in (1)through (6) below. puted distance from the traverse station to the microphone position and (1) A traverse is performed roughly places a hub at the microphone posiparallel to the line of the sound ba se, tion. To prevent errors, the frontfollowing the best traverse route. A tapeman should give all taping pinstraverse station is established at a to the rear tapeman except thosepoint from which the microphone actually required to make the distanceposition is visible. A traverse station measurement. If it is necessary tois established for each microphone. break tape, the no-rmal pin procedure (2) The azimuth and distance from the should be followed (para 87). Whentraverse station to the microphone the front tapeman has placed hi~ lastposition are computed on DA Form pin in the ground, he should pull the6-1 by using the coordinates of the tape forward a partial tape lengthtTaverse station and the predeteruntil the rear tapeman can hold themined coordinates of the microphone. proper graduation over the last tapThe microphones must be located relaing pin (para 89). The front tapemantive to each other within a tolerance should then place the hub in theof 0.5 meter. ground, at the point directly under(3) The direction of the microphone posithe zero graduation on the tape. Thetion is established by setting off on tapemen should then check their the theodolite the horizontal angle, at work by taping the distance from thethe traverse station, from the rear hub back to the traverse station.traverse station to the microphoneposition. This angle is determined by ( 6) As an example of the method of essubtracting the azimuth to the reaT tablishing the distance from the traverse station from the azimuth to traverse station to the microphonethe microphone position. The value position, assume this distance to be'that must be set on the horizontal 130.67 meters. This distance consistscircle. of the theodolite is equal to of four full tape lengths and a partial AGO 10005A 23 tape length of 10.67 meters. The front establish the microphone position and compartapeman gives seven taping pins to ing the measured direction with the computed the rear tapeman and retains four direction with the computed direction to the t pins before starting the distance measurement. When the front tapeman has placed his fourth pin in the ground, he pulls the tape forward a partial tape length so that the rear tapeman can hold the 10.67-meter graduation directly over the last taping pin. The front tapeman then places the hub in the ground under the zero graduation on the tape. b. The location of the microphone position hub can be checked by using the hub as a traverse station. It can also be checked by measuring the direction to the hub from a traverse station other than the one used to hub. c. If sound ranging microphones are established from a traverse based on assumed data for the starting station, the coordinates of the microphone positions must be converted to the common grid when the correct grid data for the starting point become available. No change in the ground location of the m icrophones is r equired. 53. Survey Control for Flash Ranging Observation Posts Flash ranging observation posts are located in the same manner as observation posts for field artillery battalions. I t r , AGO 10005A 24 CHAPTER 4 OTHER ARTILLERY UNIT SURVEYS Section I. FIELD ARTILLERY GROUP SURVEYS 54. Field Artillery Group mander. If survey control has not been fur a. The field artillery group headquarters batnished to the battalion group by the artillery tery has no capability for performing survey headquarters with which it is working, theoperations. The battalions of the group are norcommander of the battalion group directs themally f urnished survey control by the artillery survey officer of his battalion to establish a headquarters with which the group is working. battalion group survey control point. VVhen survey has not been furnished by such headquarters, the group commander may desig56. Field Artillery Missile Command, nate one battalion to establish a group survey Air Transportable control point. VVhen heavy battalions of a group a. The survey requirement of the missileare required to perform target area surveys, command, air transportable, consists of the lothe group commander usually designates one cation and orientation of the weapons and tarbattalion to perform the target area surveys get locating installations of the command. Thefor i:he entire group. firing element of the missile command is one b. The group assistant intelligence officer Honest John (Little John) battalion. The sur(assistant S2) is also the group survey officer. vey officer of the Honest John (Little John)During training, the group survey officer subattalion serves as the survey officer for t hemissile command. There are no survey person pervises the training of the survey personnel of the battalions of the group. The group surnel authorized in the headquarters company, vey officer coordinates the survey operations of missile command, air transportable. the battalions of the group. He verifies that b. The missile command, air transportable,survey control points are provided by the next receives engineer survey support from the tophigher survey echelon. He verifies, by frequent ographic engineer survey section of the organic inspections, that the survey sections of thegroup battalions perform survey operations engineer combat company. The engineer survey personnel establish survey control points as properly. Two enlisted survey specialists are required by the Honest John (Little John) batassigned to group headquarters battery for the talion. purpose of assisting the group survey officerin carrying out his responsibilities. c. The Honest John (Little John) battalion is authorized two 8-man survey parties to ex 55. Field Artillery Battalion Group tend control to each of the four launchers. Thesurvey parties locate the launchers to fifth In addition to normal survey responsibilities, order accuracy and provide direction for ori the commander of a battalion group has surveyresponsibilities similar to those of a group com-entation of the launchers and wind measuring sets (windsets). Section II. AIR DEFENSE ARTILLERY SURVEYS 57. General be performed by or in support of air defense a. Four major factors determine the type artillery (ADA units). These factors are theand the extent of survey operations which must ( 1) Type of mission assigned to the unit. AGO 10005 A 25 known so that an early warning system can be(2) Availability of maps. established. When suitable maps are available,(3) Restrictions placed on air defense fire. the relative locations of the weapons and obser (4) Fire distribution system being used. vations posts are determined by map inspection. When suitable maps are not available, the b. When air defense artillery units are assigned air defense missions, they must be caparelative locations can be established by limited rough survey as explained in FM 21-26. ble of transmitting, from one unit to another, information concerning the location of aircraft. b. When there are restricted areas, surveyTo transmit this information, the units must be control is established to determine the relativelocated with respect to a common grid. When horizontal and vertical locations of each weapsuitable maps are available, units can be loon and to provide an orienting line for eachcated. with respect to a common grid by map weapon. Control is extended to each weaponinspection for both position and direction. from survey control points established within When suitable maps are not available, units 1,000 meters of the position. Extension of conmust be located with respect to a common grid trol to the weapons must be performed to a preby extending control to each unit from control scribed accuracy of 1:500. points located on the grid. c. When ADA AW battalions are required toc. When air defense artillery units are asaccomplish the surveys discussed in b above,signed air defense missions and are restricted the necessary survey support must be madefrom firing in certain areas, they must be loavailable from the sources outside the batcated with respect to the grid on which the talion. limits of the restricted areas are designated. Units must be located on the grid by extending control to each fire unit from control points lo59. Acquisit ion Radars cated on the grid. a. The location of each air defense artillery acquisition radar position must be established d. When air defense artillery units are ason the UTM (or UPS) grid for the zone. Whensigned field artillery type missions, their survey suitable maps are available, the position can be requirements are the same as those for field arlocated by scaling from a map, and directiontillery units. can be determined with a declinated aiming e. Air defense artillery battalions normally circle. do not have the capability of performing sur b. When suitable maps are not available, the vey. Control must be extended by an agency having suitable survey equipment and trained horizontal and vertical locations of each acqui survey personnel. Arrangements should be sition radar are determined and a line of made for the nearest engineer or artillery unit known direction established by extending con capable of providing the control to perform the trol from a control point on the UTM (or UPS) necessary survey operations. When employed in grid for the zone by survey operations executed a corps area, coordination for extending survey to fifth-order accuracy. control to air defense artillery units should be made through the corps artiller y survey officer. 60. Air Defense Artillery Battalions a. Nike-Hercules. The location of each target 58. Surveys for Air Defense Artillery tracking radar of air defense artillery bat Automatic Weapons Battalions Not Equipped With Electronic Fire Control talions, Nik e-Hercules, must be established on the UTM (or UP S) grid for the zone. The a. Unless there are restricted areas, survey altitude above mean sea level and a line ofcontrol is not required for air defense artillery known direction for each target tracking radarautomatic weapons (ADA AW) battalions not must also be established. Location and altitudeequipped with electronic fire .control systems. above mean sea level must be established to anHowever, the relative locations of weapons and accuracy of artillery fifth-order survey, and t heearly warning observation posts must be t AGO 10005A 26 line of direction to plus or minus one minute of arc (0.3 mil). Survey operations may be performed by engineer or artillery units poss.essing the necessary capability. Temporary survey control may be established by scaling from a map, when suitable maps are available, and by using a declinated aiming circle. However, the accuracy thus obtained is adequate only for the surface-to-air mission and is acceptable only as a matter of expediency. Extension of survey from the target tracking radars to other battery radars and to the launching sections is performed by battery personnel using organic equipment . The accuracy required for this survey extension to other battery radars is prescribed in equipment technical manuals; the accuracy required to launching sections is 1:500. b.Hawk. Directional control for Hawk battalions may be established by scaling from a map, when suitable maps are available, and by using a declinated aiming circle. 6 1. Air Defense Arti ll ery Fire Distribution Systems The location of each fire distribution system must be established on the UTM (or UPS) grid for the zone. Survey operations may be performed by engineer or artillery units possessing the necessary capability. An accuracy of artillery fifth-order survey is required. AGO 10005A CHAPTER 5 SURVEY PLANNING Section I. GENERAL b. Mission. The overall mission of the unit 62. Survey Missions as well as the survey mission will affect sur a. The general mission of artillery survey vey planning. The survey officer, in his planpersonnel is to provide accurate and timely surning, must be aware of the general situation vey information and control to artillery units as well as the details.and installations. Successful accomplishment of this mission requires careful preparation and c. Installations That Require Survey Control. The number and locations of installations the formulation of a survey plan which is as that receive survey control will be determinedcomplete as possible. by the time and personnel available. The sur b. The specific mission of artillery survey vey operations necessary to locate a small personnel for any survey operation is connumber of widely scattered installations will tained in orders and instructions issued by the often require more time and/ or personnel than organization commander. These orders and inwould be required for a large number of structions are contained in the unit SOP, operaclosely grouped installations. In t he survey tions orders, and training directives. plan, tasks should be allocated so that the various parties executing the survey will com c. After the commander has issued orders plete their tasks at approximately the same and/ or instructions which require the executime. This might require, for example, the use tion of survey operations, the survey officer of two parties to establish control for one inmust plan the operations and issue necessary stallation located at a considerable distance instructions to survey personnel to execute the from the starting point while one party estabassigned mission. lishes control for three installations located relatively close to the starting point. 63. Factors Affecting Survey Planning d. Amount of Survey Control A vailable. The aTtillery survey officer must consider More extensive survey operations are required many factors in formulating the plan by which in areas where limited survey control exists the survey mission is to be accomplished. The than are required in areas where survey confactors which affect survey planning cannot trol is dense. be considered independently because each is re e. Number and Status of Training of Per lated to the others. sonnel. Sufficient trained personnel must be a. Tactical Situation. The survey planner available to perform the required survey in the must consider both the enemy and friendly allotted time. The survey plan must be based situations as they affect survey operations. He on the use of methods which are completely must consider the enemy's capability to interfamiliar to all personnel. fere with or restrict sUTvey operations. He f. Time. The time allotted for survey will inmust consider the locations of friendly eletiuence not only the choice of methods to bements and their missions. He must consider used but also the amount and type of controlany restrictions that the situation places on which can be extended. travel and/ or communication. AGO 10005A 28 g. Terrain. The survey officer should be so commander or indicated by the tactical situafamiliar with the effects. of various types of tion must be considered in developing the sur terrain on survey operations that he can vey plan. promptly and properly assess the time and per sonnel required for a particular operation. 64. Essentials of a Good Survey Plan h. Weather. Bad weather may eliminate or In formulating the survey plan, the survey greatly reduce the capability of survey parties. officer should remember and strive to meet cerFog, rain, snow, or dust can reduce visibility tain essentials. The survey plan mustto the extent that observations through an instrument are impossible. Heavy rain or snow a. Be Simple. The plan must be understoodcan make fieldwork impossible. Extreme heat by all personnel.or cold can reduce the efficiency of a party tothe extent that the time necessary to finish a b. Be Timely. The plan must be capable ofphase must be considerably increased. Trilatexecution in the time allotted. eration can often be conducted when weather c. Be Flexible. The plan must be capable ofconditions prevent the use of other methods being changed if the situation warrants aof survey. change. i. A v ailabili ty of Speci al Survey Equipment.Consideration must be given to the availability d. Be Adaptable. The plan must be adaptable and operational readiness of such special equipto the terrain, situation, personnel available, etc. ment as the Tellurometer, the DME, and the azimuth gyro. The presence or lack of such e. Provide fo1· Checks. Whenever possible, equipment can greatly affect the time and work the plan must provide for checks; i.e., closedrequired for a survey operation. In addition, surveys, alternate bases, and checks made bythe proper use of special techniques, such as each member of the party.simultaneous observation, can materially aff ect the accomplishment of the survey mission. f. Provide R equired Control. The plan mustpr.ovide survey control with the required accu j. Priority. Priorities established by the racy to all installations which require survey. Section II. STEPS IN SURVEY PLANNING 65. General 67. Map Reconnaissance The steps in survey planning are gathering A map reconnaissance is performed by usinginformation, making a map reconnaissance and any suitable map or map substitute. The firsta ground reconnaissance, and formulating a step in making a map reconnaissance is to plotsurvey plan. These steps are discussed in parathe installations requiring control on the map. graphs 66 through 69. The survey officer then evaluates t he factors affecting the survey plan and 66. Gathering Information a. Makes a tentative choice of survey methThe survey officer must gather all possible ods, based on the terrain shown on t h e map. information which might influence his plan.The factors affecting survey planning outlined b. Determines whether the survey missionin paragraph 64 will indicate what informacan be accomplished in the allotted time withtion is needed. The information can be obtained the personnel available. If the mission cannotfrom the commander's briefing, from members be accomplished in the allotted time, he makesof the staff, from other survey sources, from appropriate recommendations to his commanpersonal observation and from his own knowlder. For example, he can recommend that addiedge of, and experience with, his men and tional survey personnel be made available, t hatequipment. the time allotted for survey be increased, and/ AGO !0005A 29 A general ground reconnaissance can be peror that certain installations be given a low priformed by motor vehicle, aircraft, or otherority. means, but a detailed ground reconnaissance • c. Makes a tentative survey plan, noting the should be performed on foot if time permits. If • critical areas which will require detailed no suitable map or map substitute is available, ground reconnaissance. the survey officer must take the action indicated in paragraph 67 after performing the d. Issues the necessary warning order to the general ground reconnaissance but before persurvey personnel. forming a detailed ground reconnaissance. 68. Ground Reconaissance 69. Formu lation of the Survey Plan The survey officer makes as complete a reOn completion of the ground reconnaissance connaissance of the ground as time permits. He and after considering all of the factors and inmakes a detailed reconnaissance of those critiformation at his disposal, the survey officer cal areas noted during the map reconnaissance. modifies his tentative plan. Section Ill. THE SURVEY ORDER 72. Changes to the Survey Order70. Genera l The survey plan becomes a survey order The survey officer closely supervises the work of the survey parties to insure that the when specific instructions are given to each survey party. The survey order contains those order is properly executed and to detect any situation that may necessitate changes in the instructions which are not covered by the survey plan. If it becomes necessary to change standing operating procedure and which are the plan of survey, he issues appropriate innot general information but are necessary for structions to the party chief(s) concerned. the efficient accomplishment of the survey mis sion. 73 . Execution of the Survey Order Each chief of survey party plans the detailed 71 . Sequence in W hich Survey Order Is operations of his party. His planning is similar Issued to that of the survey officer. The mission of his The survey order may be issued by radio, party is contained in the instructions issued by wire, or both. The survey order is issued in the the survey officer. The survey plan prepared and issued by the chief of party contains those five-paragraph sequence of an operation order, items from the survey officer's order which hisas follows: personnel must know to accomplish the survey 1. SITUATION (as it affects the survey mission and any additional instructions whichoperations) may be necessary. The chief of party supervises a. Enemy forces. the operations of his party and issues addi b. Friendly forces. tional instructions as necessary throughout the c. Attachments and detachments. conduct of the survey. Whenever it becomes impracticable to comply with the instructions re 2. MISSION (survey) ceived from the survey officer, the chief of 3. EXECUTION party reports this fact to the survey officer or a. Concept of survey operations. chief surveyor if either is immediately avail b. Detailed instructions to each party. able. If neither is immediately available, the chief of party changes his survey plan as neces c. Instructions for more than one party. sary to accomplish that portion of the unit's 4. ADMINISTRATION AND LOGISTICS survey mission for which he is responsible. As 5. COMMAND AND SIGNAL (location of the first opportunity, he reports the action survey officer) which he has taken to the survey officer. AGO 10005 A 4 30 Section IV. STANDING OPERATING PROCEDURE 74. General not be restated in the survey order. For exam a. A standing operating procedure (SOP) is ple, if the battalion SOP prescribes the size ofa set of instructions setting forth the procedistance angles for triangulation, this informadures to be followed for those phases of operation need not be included in the survey order.tion which the commander desires t o make However, inclusion of this information in theroutine. The SOP sets down the regular proceSOP would not preclude the s urvey officer fromdures that are to be followed in the absence of restating it in the survey order for emphasis.specific instructions. b. Simplify and Perf ect the Training of Sur b. The SOP of a battalion (separate battery) vey Personnel. Establishment of standard proor higher artillery headquarters should contain cedures for survey operations in a unit insuresa section on survey. The SOP for each echelon unif orm training and minimizes the need formust conform to the SOP of the next higher special instruction.echelon. Therefore the survey portion of theSOP at each artillery echelon should contain c. Promote Understanding and Tectm work.only those survey procedures which the comIn those units which have more than one survey party, the establishment of standard procemander desires to make standard throughout his command. Survey items which the commandures insures uniform performance of surveyopentions and minimizes the time and effort der desires to make standard only for the surrequired for coordination. vey unit or section of his headquarters should be contained in the SOP for that particular unit d. Facilitate and Expedite Survey Opera or section. tions and To Minimize Confusion and Errors. When personnel become familiar with, and em 75. Purposes of Survey Section SOP ploy, standard signals, techniques, and proceThe purposes of the survey section SOP are dures, they will accomplish their tasks in ato-minimum amount of time. Furthermore, theuse of standard procedures reduces confusion a. Simplify the Transmi ssion of the Survey and eliminates many errors, which, in turn, Order. Instructions included in an SOP need speeds up survey operations. AGO 10005A 31 PART TWO POSITION DETERMINATION CHAPTER 6 DISTANCE DETERMINATION Section I. HORIZONTAL TAPING oiled by running it through an oily rag as it is 76. Tapes and Accessories being reeled in. The tape should be loosely a. Field artillery survey personnel are wound on its reel when not in use. In winding equipped with 30-meter steel tapes for making the tape on the reel, the tapeman should insert linear measurements (taping). These tapes are the end of the tape with the 30-meter graduagraduated on one side only, in meters, decitions into the reel and wind the tape so that the meter), and centimeters (0.01 meters (0.1 numbers are facing the axle of the reel. meter), with the first decimeter graduated in millimeters ( 0.001 meter). There is a blank 78. Repair of Broken Tape space at each end of the tape. A reel and two leather thongs are furnished with each tape. a. A broken tape can be repaired by fitting a sheet metal sleeve, coated on the inside with b. In addition to a tape, each taping team solder and flux, over the broken ends of theshould be equipped with 2 plumb bobs, 1 pin tape. The sleeve is hammered down tightly, andand plumb bob holder, 1 clamping handle, 1 set heat is applied to the sleeve to cause the solderof 11 taping pins, 1 hand level, 1 tension han 4 to securely bind the broken ends of the tape dle, 2 leather thongs, 2 notebooks, and 2 penwithin the sleeve. An ordinary match may be cils (fig. 9). used to heat the solder. b. The repaired section of the tape must be 77. Care of Steel Tapes checked with another section of the tape to in a. Steel tapes are accurate surveying instrusure that the ends of the tape were joined and ments and must be handled with care. Although that the tape still gives a true measurement. steel tapes are of durable construction, they can be easily damaged through improper care 79. Horizontal Taping, General and use. a. The method of taping used in artillery b. When a steel tape is being used, it should surveys is known as horizontal taping. In this be completely removed from its reel and kept method, all measurements are made with the straight to prevent its being kinked or broken. tape held horizontally. The point from which The tape should never be pulled around an obthe distance is to be measured is the rear staject that will cause a sharp turn in the tape. tion. The point to which the distance is to be Care should be taken to avoid jerking or step measured is the forward station. The distance ping on the tape or allowing vehicles to run between stations is usually several times over it. A loop in the tape may cause the tape greater than a full tape length. The taping to kink or break when tension is applied. Beteam, starting at the rear station, determines fore applying tension, the tapemen should inthe distance by measuring successive full tape sure that there are no loops in the tape. lengths until the distance remaining is less c. The tape should be wiped clean and dry than a full tape length. This length is then measured.. The distance between stations is de and oiled lightly after each use. The tape is AGO 10005A 32 - • • -1 Figure 9. Taping equ ipment. termined by multiplying the number of tape session. The pin given to the rear tapeman replengths by the length of the tape and adding the resents the first full tape length. The frontpartial tape length. tapeman moves toward the forward station b. A taping team consists of two men-a with the zero end of the tape. front tapeman and a rear tapeman. The rear b. As the end of the tape reaches the reartapeman commands the taping team. The rear station, the front tapeman stops, either on histapeman determines and reports the distance count of paces or on the command TAPE givenmeasurement; the front tapeman independently by the rear tapeman. The rear tapeman sightschecks the distance measurement. Additional toward the forward station and signals the dipersonnel are required for taping at night rection that the front tapeman should move to(para 92). aline the tape, first with the forward station and then in an estimated horizontal plane. The 80. Measuring First Full Tape Length tape must be alined within 0.5 meter of the line The first full tape length is measured using of sight from one station to the succeeding stathe following procedures: tion and within 0.5 meter of the horizontalplane. a. The front tapeman gives 1 taping pin tothe rear tapeman, keeping 10 pins in his pos-c. Each tapeman places a leather thong on AGO 10005A 33 his wrist and the plumb bob cord on the proper 82. Moving Forward graduation on the end of the tape. The rear a. The front tapeman should select a land-• tapeman alines his plumb bob roughly over the mark (rock, bush, etc.) in line with the for-• rear station and commands PULL, and the ward station. In moving forward, the front tapemen exert a pull of 25 pounds on the tape. tapeman shocld keep his eyes on the line to the forward station and should not look back. He d. After the tapemen have properly alined should determine the number of paces to theand applied tension to the tape, the rear tapetape length so that he can stop without beingman places his plumb bob exactly over the rear signaled when he has moved forward a tape.station and commands STICK. At this com length. mand, the front tapeman drops his plumb bob and then marks the point of impact with a b. By moving forward at a point 2 or 3 taping pin. When the pin has been placed meters in front of the rear end of the tape, the firmly in the ground, the f.ront tapeman rerear tapeman can usually locate the taping pin ports STUCK, which instructs the rear tapeby the time the front tapeman has stopped. man to move forward to measure the next tape c. When there is an instrument used at eitherlength. the forward or the rear station, the tapemen e. When a team is taping on gently s.loping must remain clear of the line of sight. ground void of brush and tall grass, the plumb bob need not be used at the uphill end of the 83. Tape Alinement tape. The end of the tape may be held immedi The tapemen must carefully aline the tape. ately adjacent to the taping pin. The maximum allowable error in both hori zontal and vertical alinement is one-half meter 81. Measuring Succeeding Full Tape Lengths for a full 30-meter tape length. The tapemen aline the tape with the stations which estab- Succeeding full tape lengths are measured as lish the line by sighting along the tape towarddiscussed in paragraph 80, except as follows: the stations at each end of the line (fig. 10). a. The front tapeman should obtain his apThe tapemen then level the tape horizontally proximate horizontal alinement by sighting by holding it parallel to an estimated horiback along the tape toward the rea·r station, zontal plane. If difficulty is encountered in moving right or left until the tape is approxikeeping the tape level in rough terrain, then mately on line. Final alinement usually is made the hand level should be used. To use the hand as directed by the rear tapeman. However, if level to establish a horizontal plane, the downthe rear tapeman cannot see the forward staslope tapemantion, final alinement is made either by the front a. Sights. through the level at the upslopetapeman sighting back on the rear station or tapeman. by the rear tapeman through the use of pre viously selected reference points in alinement b. Raises or lowers the objective end of the with the forward station. The inshument ophand level until the image of the level bubble is erator, if available, may assist in this alinecentered on the center horizontal crossline. ment. c. Determines the point on the upslope tapeman which is level with his eye. This estab b. The rear tapeman should place his plumb lishes the horizontal plane. bob exactly over the point at which the taping pin enters the ground. d. Instructs the upslope tapeman how to hold his end of the tape so that the tape will be c. The rear tapeman pulls the taping pin parallel to the established horizontal plane. Thefrom the ground before moving forward to the downslope tapeman must hold the tape no next pin position. If a taping pin is lost during higher than his armpits. the measurement of the distance, the tapeman Note. The tapeman should check the accuracy of the must tape the entire distance again, rather than bubble of the hand level when it is first used each day. complete the taping from a recovered pin hole. This is accomplished by having the upslope tapeman AGO 10005A 34 FORWARD STATION Figure 10. Tape alin ement. use the hand level to sight on the downslope tapeman b. The clamping handle is used to hold theto verify the established horizontal plane. tape at any point other than a tape end. In order to avoid kinking the tape, the tapeman 84. Applying Tension to Tape should hold the clamping handle with the index The tapeman must apply 25 pounds tension and middle fingers. Normally, the handle will (pull) to each full or partial tape length. clamp as tension is applied to the tape. If addi a. The tapeman should apply tension to the tional pressure is required, it is applied to thetape by using the leg muscles and the large outside of the finger grips by using the thumbmuscles of the back. To do this, the tapeman and ring finger.faces across the tape with his shoulders parallel c. The tension handle (a scale which measto the length of the tape, passes the hand of ures tension in pounds) should be used by the the arm which is away from the other tapemanthrough a loop in the thong, and places the elfront tapeman until both tapemen become accustomed to the "feel" of 25 pounds tension. bow of that arm tight against some part of hisbody (fig. 11). When the tapeman is standing,he applies tension by bending the knee which is 85. Use of Plumb Bobs away from the other tapeman, causing the The tapemen use plumb bobs to projectweight of the body to push against the arm points on the tape to the ground. Each tapemanholding the tape. When the tapeman is kneel holds the plumb bob cord on the proper tapeing, he applies tension by pushing the knee graduation with the thumb of one hand on the which is away from the other tapeman against cord and the forefinger of that hand beneath the arm holding the tape. the tape (fig. 11). After alining the tape and • AGO 10005 A 35 FRONT TAPEMAN REAR TAPEMAN F igure 11 . Applying tension to a tape. point struck by the tip of the plumb bob by applying tension to it, each tapeman lowers the sticking the pin into the ground at exactly that plumb bob by letting the cord slip across the tape until the tip of the plumb bob is approxipoint. The shaft of the pin should be placed at an angle of about 45 ° with the ground and per mately one-fourth inch above the desired point. Swinging of the plumb bob i s eliminated by pendicula r t o the length of the tape. When moving f orward, the tapem en should not pull the gently lowering the tape until the plumb bob tip touches the ground and then slowly raising it. tar1 e thr-ou gh the loop of the taping pin. When taping over a hard surface, it may be necessary a. The rear tapeman uses his plumb bob to to mark the point struck by the plumb bob in an position his end of the tape directly over the identifiable fashion (point of taping pin or pen point from which each tape length is measured. cil). The point of the pin should be laid at the point struck by the plumb bob, perpendicular b. The front tapeman establishes the point to the line of direction of the tape. on the ground to which each length is measured by dropping his plumb bob. After establishing 87. Brea king Tape the point with the plumb bob, the front tapeman marks the point with a taping pin. The When the tape cannot be alined within onerear tapeman can locate each pin more readily half meter of a horizontal plane because of the if the front tapeman clears the ground of grass, slope of the ground, the tapemen use a special leaves, etc. or kicks a groove in the ground. procedure known as breaking tape (fig. 12 ) . The procedure for breaking tape is as follows: 86. Use of Taping Pins n. The front tapeman pulls the tape forward a full tape length, drops. it approximately on The tapemen must use the taping pins to line, and then comes back along the tape until mark points on the ground for each full or par tial tape length. The front tapeman marks the he reaches a point at which the tape, when held AGO 100 05 A .. 36 30 METERS GRADUATION ~,,;5-METER GRADUATION ~~~~~~--~ I Figure 12. Breaking tape. level, would be no higher than the armpits of which is 10 full tape lengths from the rear stathe downslope tapeman. At this point, the front tion. The front tapeman waits at the last pin tapeman selects any convenient full meter gradposition until the rear tapeman comes forward.uation. The tapemen then measure the partialtape length, applying the full 25-pound tension b. Both tapem en count the pins to verify that to the tape. Clamping handles are used at any none have been lost. (One pin is in the ground;holding point between ends of the tape. 10 pins should be in the possession of the reartapeman.) b. After he has placed the taping pin, thefront tapeman waits until the rear tapeman c. The rear tapeman gives the front tapemancomes forward. The front tapeman tells the the 10 pins. rear t a peman which full meter graduation was d. Both tapemen record 10 tape lengths and used, e.g., HOLDING 25. The rear tapeman rethen continue taping. peats HOLDING 25. The front tapeman re ceives a pin from the rear tapeman and moves 89. Measuring Partial Tape Lengths forward, Tepeating this procedure until the zeromark on the tape is reached. To measure the partial tape length between the forward station and the taping pin repre c. When holding a point on the tape other senting the las.t full tape length, the tapementhan the zero graduation, the front tapeman use the following procedure: must recei?Je a pin from. the rea1· tapeman before moving forward. a. The front tapeman moves to the forwardstation and places the plumb bob cord on the 88. Measuring Distances in Excess of zero graduation of the tape. The rear tapemanmoves forward along the tape to the taping pin. 10 Tape lengths b. If slack is needed, the front tapeman comTo measure a distance longer than 10 full mands SLACK and the rear tapeman allows the tape lengths, the tapemen use the procedures tape to move forward. When the front tapemandiscussed in paragraphs 80 through 87 except ir; ready, he commands PULL and the tapemenas follows: e>,ert a pull of 25 pounds on the tape. To exert a. When the front tapeman has set his last this pull, the rear tapeman uses, a clampinghandle to hold the tape. As tension is applied to pin in the ground, he has established a point the tape, the rear tapeman slides his plumb bob AGO 10005A 37 marking the half tape length represents one fullcord a long the tape until the plumb bob is extape length plus 15 meters. After the startingactly over the pin. station i.s established a half tape length fr01n c. When the zero graduation is exactly over the rear stcdion, the taping procedures are the the forward station, the front tapeman comsame as those discussed in paragraphs 80 mands READ. The rear tapeman reads the through 90, except that each tapeman adds 15graduation marked by his plumb bob cord and m et ers to the distance measurem·ent. This proannounces the measurement of the partial tape cedure precludes both teams placing their taplength to the nearest 0.01 meter. ing pins in the same hole. d. The front tapeman repeats the reading aloud, and both tapemen record the measure92. Taping at Night ment. Daytime taping methods may be used at night with certain modifications. A piece of white 90. Taping at an Occupied Station cloth should be tied to each end of the tape to When a taping team is making a measureassist the tapemen in following and locating ment at a station occupied by an instrument, the tape. Three men should be added to each the tapeman at the station must be careful not taping team. One man accompanies each tape to disturb the instrument. If a plumb bob is man as a light holder; the third man marks the taping pin. When the rear tapeman comes to theused with the instrument, the tapeman can taping pin, the third man walks the length ofmake his measurement at the plumb bob cord the tape, freeing it from any obstructions. This of the instrument. procedure is repeated for each full or partial tape length. The light holders must obs.erve se 91. Use of Two Taping Teams curity precautions when using their lights. When two taping teams are used to measure the distance between two stations, one taping 93. Determining Taped Distance team uses a pin to establish a starting station a half tape length (15 meters) from the rear The tapemen determine and check the dis station. In this. case, the front tapeman does not tance measurement (fig. 13), using the follow give a pin to the rear tapeman. The taping pin ing procedures: FRONT TAPEMAN REAR TAPEMAN 10-4 = 6 6 X 30 =180.00 6X 30.00 =180.00 + 13 . 74 + 13.74 193 .74 193.74 Figure 13. Determining taped distance'. AGO lOOO oA 38 a. Each tapeman counts the number of pins measurement to the recorder for entry in thein his possess.ion. (The pi n in the ground at the fi eld notebook. last full tape length is not counted.) 94. Comparative Accuracy for Double-Taped b. The rear tapeman determines the distance Distancesmeasurement by multiplying the length of thetape (30 meters) by the number of full tape a. When the distance between two stations lengths measured and adding the partial length has been determined by double-taping, the twomeasurements are compared and the compara read from the tape. (The number of full tape lengths measured is equal to 10 for each extive accuracy for the two measurements is dechange of pins plus the number of taping pins termined. Comparative accuracy is expressed in h'is possession.) as a ratio between the difference in the measurements and the mean of the measurements. c. The front tapeman independently checks The ratio is expressed with a numerator of 1;the distance measurement by multiplying the e.g., 1/ 1,000 or 1:1,000. The denominator is delength of the tape by the number of full tape termined by dividing the mean of the measurelengths measured and adding the partial tape ments by the difference in the measurelength. (The number of full tape lengths measments. After computing the comparativured is equal to 10 for each exchange of pins accuracy, the denominator of the fraction is a1plus the differ ence between 10 and the number ways reduced to the next lower hundrec; . of pins in his possess·ion..) b. The following example illustrates the computation of a comparative accuracy for a dL d. The rear tapeman reports the distance tance measurement: I Distance measurement by taping team 1 375.84 meter;;; ~ Distance measurement by taping team 2 357.76 mete1·sDifference between measurements 0.08 meterMean of the measurements 357.80 meters difference 0.08 0.08 0.08 Comparative accuracy = ---mean 357.80 357.80 0.08 1 1 1 --or- 357.80 0.08 4472 4400 c. When the double-taped distance does not a. Traverse. meet the required comparative accuracy, the distance must be taped a (1) 1:500-single-taped; checked by pac third time. The third measurement is then compared with each ing. of the first two measurements to determine if (2) Fifth-order (1:1,000) -'Single-taped; a satisfactory comparative accuracy can be checked by pacing. achieved with one or the other. The unsatis (3) Fourth-order (1:3,000)-double-tapecifactory distance is then discarded. to a comparative accuracy of 1:5,000. b. Triangulation, Intersection, and Resection.. 95. Taping Techniques and Specifications (1) 1:500-double-taped to a comparative To achieve the various degrees of accuracyin survey, distances must be determined acaccuracy of 1:3,000. curately to within certain specifications, de(2) Fifth-order (1:1,000) -double-tapedpending on the method of survey used. Taping to a comparative accuracy of 1:3,000.techniques and prescribed accuracies for the (3) Fourth-order (1:3,000)-double-tapeddifferent methods of survey are as follows: to a compa-rative accuracy of 1:7,000. AGO 10005A 39 c. Systematic errors can be due to improper 96. Errors in Horizontal Taping repair of the tape (repaired too long or too Horizontal taping errors fall into three cate-short), causing taped distances to be longer or gories, as follows: shorter than their true distances. a. Systematic errors. 98. Accidental Errors b. Accidental errors. Accidental errors are errors which may ac c. Errors caused by blunders. cumulate in either direction. Accidental errors are usually minor errors. The principal acci 97. Systematic Errors dental error encountered in taping is caused by small errors in plumbing. Tapemen should be Systematic errors are errors which accumucareful in plumbing over points, and when late in the same direction. taping in strong winds they must be especially a. The systematic errors encountered in horicareful to minimize swinging of the plumb bob zontal taping cause distances to be measured cord. This can be accomplished by keeping the longer or shorter than their true lengths. The plumb bob close to the ground. principal causes of systematic errors are 99. Errors Caused by Blunders (1) Failure to aline the tape properly. (2) Failure to apply sufficient tension to Blunders are major errors made by personthe tape. nel. (3) Kinks in the tape. a. The principal blunders made by tapemen are b. Systematic errors can be eliminated or (1) An incorrect exchange in taping pins. minimized by strict adherence to proper proce dures and techniques. Tapemen should be (2) An error in reading the tape. especially attentive to keeping the tape hori(3) An omission of the half tape length zontal when taping on a slope and should break when double-taping with two teams. tape when necessary. They should avoid the (4) Loss of a taping pin. tendency to hold the tape parallel to the slope. b. Blunders can be detected and eliminatedWhen taping in strong winds, tapemen must by strict adherence to proper procedures andbe especially careful to apply the proper ten sion to the tape. Tapes should be checked freby adoption of a system of checks; e.g., by double-taping, by pacing each taped distance, quently for kinks. One of the chief causes for and, in some cases, by plotting the grid coorkinked tapes is improper use of the clamping dinates of the stations on a large-scale map. handle. Section II. TELLUROMETER MRA 1/CW/MV ing the loop transit time of radio microwaves 100. General from the master unit to the remote unit and The Tellurometer is an electronic distanceback and converting one-half of this loop tranmeasuring device issued to artillery units resit time to distance. Optical line of sight is not quired to perform fourth-order survey (fig. 14). required, but electrical line of sight between The Tellurometer system consists basically of the instruments is required. The minimum one master and two remote units. The major range capability of the equipment is 152 components for both the master and remote meters, and the maximum capability is 64,000 units are described in paragraph 101. Addimeters (40 miles). Approximately 30 minutes tional items used to complete a Tellurometer is required to measure and compute a distance regardless of the length of the measurement. measurement include the altimeter (when sta tions are not intervisible), Tellurometer field A distance can be measured during daylight or record and computations forms, and logarithdarkness and through fog, dust, or rain. A dis tance measured with the Tellurometer is used mic tables. Distance is determined by measur- AGO 10005A 40 and communication systems. A luggage-typehandle facilitates carrying the instrumentwhen it is removed from its case. The hingeddoor in the lower left corner of the controlpanel (figs. 15 and 16) opens into a compartment in which the radiotelephone handset isst ored. A cathode-ray tube (CRT) visor (fig.14) is mounted over the CRT scope to shutout light and make scope presentations moreclearly visible. b. The carrying case (fig. 14) is a lightweight, metal alloy, top-opening container. Thelid is provided with a sponge rubber seal forprotection against moisture. The case measures approximately 18 pounds; it is fitted witha luggage-type handle for carrying. The casealso has a backstrap device which permits theoperator to carry it on his back. The case isfitted to hold the instrument (master or remote) in place, and compartments are providedin the case for spare parts, the CRT visor, aplumb bob, a plastic rain cover, and a container of silica gel. c. The universal tripod is issued with theTellurometer; this tripod is interchangeablewith the tripod used with the T16 and T2theodolites. d. Three different power sources may be usedwith the Tellurometer. A 12-volt, 40-amperehour battery or a 24-volt, 20-ampere-hour batFigure 14. Tellurometcr station with operating tery system may be cabled directly to a built-inequipment and carrying case. powerpack (figs. 15 and 16). In addition, eithera 115-volt, 60-cycle power supply or a 230-volt,in computations in the same manner as a taped 50-cycle power supply can be utilized by meansdistance. of a mains converter (external powerpack). Afully charged battery will permit 4 to 6 hours of 101. Description of Components continuous operation. An 18-foot cable is provided RO that the built-in powerpack can be con a. The master unit and the remote units are nected to a vehicle battery for 24-volt operation. similar in appearance (figs. 15, 16, and 17) butneither the master nor the remote unit can be e. The spare parts kit consists of a smalloperated in a dual role because of the internal metal box containing tubes, regulators, lamps,characteristics. The units have the same exand fuzes. A list of these spare parts is providedternal dimensions {approximately 19 by 9 by in t he metal container. 17 inches) and each weighs 27 pounds. Both f. Additional accessories include a harnessunits have parabolic reflectors, which are (backstraps) and pack, a CRT visor, a plasticshown in the operating position in figure 17. rain cover, a screwdriver, a nonmetallic screwThe mirror surface of the reflectors radiates driver, two power supply cables, an externalthe received signal to the dipole. The dipole powerpack, a handbook (Operation and Maincontains the transmitting and receiving antenance), and the Preliminary Maintenance tennas. Both units have identical built-in aerial Suppo rt Manual. AGO 10005 A 41 CRT light Cathode ray tube (CRTl graduated Panel light ~ Handset compartment Figure 15. Control panel, maste1· unit. g. A surveying altimeter, issued as a separate entered on DA Form 5-139, Field Record and TOE line item, should be available with each Computations-Tellurometer. The computamaster and remote unit for the determination of tions for determining sea level distance are also difference in height when it is not possible to accomplished on this form. The completed form, with field records and computations, should be measure the vertical angle between the master filed with the associated survey computation. and remote units with a theodolite. The verti cal angle or difference in height is necessary to convert the slope distance measured with the 103. Principles of Operation Tellurometer to horizontal distance. a. When the Tellurometer system is used to perform a distance measurement, one master 102. Notekeeping unit and one remote unit must occupy opposite ends of the line to be measured. A continuous Field notes of the Tellurometer survey are AGO l0005A 42 4I Panel light Meterswitch Handset comportment Figure 16. Cont1·ol panel , remote unit. radio wave of 10-centimeter (em) wavelength waves, is indicated on the circular sweep of the(3,000 megacycles) is radiated from the master master unit cathode-ray tube (CRT) in theunit. This radio wave is modulated by what is form of a small break, which marks the phasereferred to as pattern frequency. The modulated on a circular scale (fig. 18). The CRT circularwave is received at the remote unit and reradiscale is divided into 10 major and 100 minorated from its transmitting system to the master gra duations. The leading edge of the break in unit. the circular sweep is read clockwise to the b. At the master unit, the return wave is smallest minor graduation. The transit time,compared with the transmitted wave, and the the time required by the wave to travel fromphase comparison, or the difference in the two the master unit to the remote unit and back, is AGO 10005 A 43 Circle amplitude----:-: Press pu lse-------!!!!!t----' Shape---------~~----~J '!•••f~!!!!l· Y amplitude------!!!!iiiiiiiil••l -------Pulse amplitude Remote I I Oipole----L~- Y shift-------~-~ X shift -----------::=--~ L-4--~~~-Focus------~~~- =---Brilliance ----__.:.:.-.:'-'-'---- F igu1·e 1 7. Side view s of 7naste1· and ?"e'mote nnits. the measurement of angles with the theodolite, determined from a series of readings on the cathode-ray tube of the master unit. the proper selection of stations for the theodo lite will provide line of sight for the Tellurometer. The best site for a Tellurometer sta 104. Selection of Stations tion is on top of a high peak; however, the folThe optical line of sight between stations lowing factors must also be considered becausemust be clear, or very nearly so, for a Telluof the effects caused by the reflection of microrometer measurement; however, visibility is waves:not absolutely essential. This condition is reground between the two stations ferred to as electrical line of sight. Large tera. Th ~ should Le broken and, preferably, covered with rain features, such as hills, will block the line of site. The Tellurometer is used primarily in trees and vegetation to absorb ground waves traverse, in which a theodolite is used to measand prevent them from interfering with the ure angles. Since line of sight is necessary for direct signal. AGO 10005A 44 - A 8 c D 05 71 85 24 A+ A- A+R A-R 05 99 59 51 Figu1·e 1 8. Cathode-ray tube pattern r eading. b. When possible, the ground should slope gradually away from each instrument. c. If possible, measurements should not be made over highly reflective surfaces, such as smooth areas, desert sands, and water. Figure 19 illustrates the effect of the reflection of microwaves from water. An error, sometimes referred to as ground swing, is caused when the Tellurometer receives both the direct wave and the reflected wave. Some of the error is removed by the method of observing. The mean of the four fine readings, each at a different cavity tune setting, removes a part of the swing error. d. The instruments should be set well back from the edge of the high land so that as much of the reflective area as possible becomes "dead ground" to the receiving instrument (fig. 19). 105. Instrument Controls The controls for the operation of the master and remote units are classified into four functional groups-the setting up controls, used initially in setting up the instruments and estab- AGO 10005A lishing a satisfactory cathode-ray tube presentation; the operating controls, used during the measurement; the monitoring controls, used to check circuit operation; and the preset controls, which normally require no adjustment. Each of thesB functional groups includes a number of 1individual controls. a. S etting Up Controls. {1) The LT (LOW VOLTAGE) and the HT (HIGH VOLTAGE) switches are used to apply power to the master and remote units after they have been cabled to a power source. These switches are located in the lower portion of the control panel on the units. (2) A BRILLIANCE control is located on the left side panel of each unit and is used to adjust the brightness of the presentation on the cathode-ray tube of each instrument. (3) A FOCUS control is located on the left side panel of each unit and is adjusted in conjunction with the BRILLIANCE Reflected Microwave~ / \...// / // / /// Reflected 1 Microwave~ / 11 ~ /~ F i gure 19. R eflect ed microw a1>es. control until a bright, sharp trace appears on the cathode-ray tube. (4) An X-SHIFT control is located on the left side panel of each unit, and it moves the trace in a horizontal direction across the face of the cathode-ray tube. (5) A Y-SHIFT control is located on the left side panel of each unit, and it moves the trace in a vertical direction across the face of the cathode-ray tube. (6) The CIRCLE AMPLITUDE control is located on the right side panel of the master unit and is used to adjust the diameter of the circular trace that is presented on the cathode-ray tube. • (7) The SHAPE control and the Y-AMPLITUDE control are located on the r ight side panel of the master unit and are adjusted together to achieve a circular trace on the cathode-ray tube. b. Operatin g Controls. (1) A PATTERN SELECTOR control is located in the upper part of the cont r ol panel of each unit and is used to select pattern A, B,-C, or D, as required, during the measuring procedure. In addition, the PATTERN SELECTOR control on the remote unit selects the A + or A-pattern upon instructions from the master unit operator. AGO 10005A (2) A MEASURE-SPEAK key is located of the battery. In the MOD position,in the center portion of the control the meter reading indicates that cirpanel of each unit and is used for cuit pattern modulation is takingswitching from radiotelephone to place. In the AVC position, the metermeasure and also for signaling during indicates the strength of the •received a measurement. signal. (The REFLECTOR TUNE (3) A CAVITY TUNE dial is located in control should always be adjusted tothe center portion of the control panel obtain a maximum AVC reading.) Theof each unit and is used similarly to three remaining switch positions arethat of a program selector on a radio. OFF positions, indicating that theEach CAVITY TUNE dial setting has SWITCHED METER (not the Tela corresponding frequency. lurometer unit) is off. ( 4) A REFLECTOR TUNE dial is located (3) A CRYSTAL CURRENT meter is lo in the center portion of the control cated in the center portion of the con panel of each unit and is used for elec trol panel of each unit and registerstrical tuning of the klystron. It should the crystal current. This reading be adjusted at all times for maximum should be kept at the maximum at all crystal current, which is indicated on times by adjusting the REFLECTORthe CRYSTAL CURRENT meter. TUNE dial. (5) The FORWARD-REVERSE reading d. Preset Controls. key is located in the center portion of the control panel on the remote unit (1) The ADJUST MODULATION con and is used to select the forward A+ trol plate located above the PAT or A-pattern or the reverse A+ or TERN SELECTOR switch on the A-pattern, as instructed by the mascontrol panel of each unit must be re ter unit operator. moved to adjust the modulation con (6) The PULSE AMPLITUDE control is trols. A nonmetallic screwdriver islocated on the right side panel of the used to adjust the modulation level ofremote unit and is used to adjust the pattern A, B, C, and D to read 40,amplitude of the pulse being returned 40, 40, and 36, respectively.by the remote unit to the master unit. (2) The ADJUST FREQUENCY control c. Monitoring Controls. plate located immediately below thePATTERN SELECTOR switch on ( 1) The PRESS PULSE control is located the control panel of each unit muston the right side panel of the master be removed to use the four controlsunit and is used by the master unit for the adjustment of crystal freoperator to verify that a pulse of suf quencies. This a.djustrment is per ficient strength is being received from formed only by a qualified technician. the remote unit. When th~> master unitoperator presses the PRESS PULSEcontrol, he is able to view on his 106. Setting Up the Tellurometer cathode-ray tube the pulse pattern Any attempt to operate a master unit andthat is presented on the remote unit a remote unit while they are pointing at eachcathode-Tay tube. other at a distance of 150 meters (500 feet) (2) A METER switch is located on the or less will result in damage to the units. The instructions contained in a through k below arecenter portion of the control panel of applicable to both the master station and the each unit and is used in conjunction with the SWITCHED METER to remote station. check circuit operation. The switch is a. Set up the tripod over the point which set to the REG position to check voltidentifies one end of the line to be measured, age regulators in the klystron circuit. using the procedure outlined for setting upIt also indicates the state of charge the aiming circle (para 148a). AGO 10005A 47 b. Remove the instrument from the case and URE-SPEAK key to MEASURE. The reading place it on the tripod head. Thread the tripod on the SWITCHED METER will vary with screw into the base of the instrument and the strength of the battery. The reading should tighten it to insure that the instrument is fixed be at least 30 to permit a satisfactory measureto the tripod. Point the dipole in the approximent. A reading of less than 30 indicates that mate direction of the remote station. The Telthe charge in the battery is too low for operalurometer radiates a conical beam of about 10° . tion. In windy weather, the Tellurometer should be i. Adjust the REFLECTOR TUNE dial for tied down so that it will not be blown over maximum crystal current. The CRYSTALand damaged. CURRENT dial should read above 0.2 for best c. Dismount the parabolic reflector from its operation. The lowest reading on the CAVITY TUNE dial will usually give the greatest closed (travel) position and remount it in the CRYSTAL CURRENT Teading. open (operating) position, making sure that the fasteners fit properly and snugly. Failure j. Turn t he METER switch to MOD (moduto do so may result in damage to the unit. late) position and check the modulation level of each crystal. The PATTERN SELECTOR d. Remove the power supply cable and the must be turned to each crystal, in turn. The telephone handset from the storage compart correct readings, as viewed on the SWITCHED ment under the control panel. Hang the tele METER should be 40 on A , B, and C and 36 on phone handset on an improvised hook or D. If these readings are not approximated, re bracket on the tripod. Never place the handset move the ADJUST MODULATION cover and on top of the unit, because inaccuracies are adjust the modulation trimmers. The trimmers created if the handset is left there during the should be adjusted if the reading varies -+-2 measurement. Place the LT and the HT from 40 or 36, depending on the crystal being switches in the OFF posi tion. checked. A nonmagnetic screwdriver should be e. When a 12-volt battery is used, connect used for t h is adjustment. the short (8-foot) 12-volt power supply cable k. Switch the MEASURE-SPEAK key to to INPUT. Connect the red lead to the positive SPEAK and move the METER switch to the post and the black lead to the negative post. AVC position. The SWITCHED METER f. When a 24-volt battery is used, connect should read about 20 microamperes without the the long (18-foot) 24-volt power supply cable two instruments being tuned and without the to INPUT. Connect the red lead to the positive other set being turned on. Turn the REpost and the black head w the n egativ e post. Do FLECTOR TUNE dial. If the SWITCHED not use the short 12-volt power supply cable METER needle moves, the receiver is working. with a 24-volt battery, because this will damage If there is no movement of the indicator, the unit. trouble can be suspected in the receiver and a ' repairman should be consulted. g. The system is Teady to be turned on after l. This step is performed by the master unit the completion of either e or f above. Place the LT switch in the ON (up) position. This proonly. Switch the MEASURE-SPEAK key to vides a filament current to the tubes in the SPEAK. There should be a spot of light nea:r instrument, and it must be turned on 30 secthe center of the cathode-ray tube. Turn the onds before turning on the . HT switch. Both CIRCLE AMPLITUDE control (right side panel) to make this spot as small as possible. the LT and HT switches must be in the ON position for operation of the instrument. The Adjust the BRILLIANCE and FOCUS controls HT switch should be in the OFF position while (left side panel) for a clear, sharp spot. Center waiting far the prearranged time of operation the spot carefully in the graticule, using the agreed upon by the master and remote opX-SHIFT and Y-SHIFT controls (left side panel). erators. h. Turn the METER switch to the REG m. While the master unit operator is complet (voltage regulator) position and the MEAS-ing the adjustment in l above, the remote unit, AGO 10005A 48 with the MEASURE-SPEAK key in the SPEAK position, should present a spot of light near the center of the cathode-ray tube. If necessary, adjust the BRILLIANCE and FOCUS controls for a clear, sharp spot and center the spot in the cathode-ray tube by using the X-SHIFT and Y-SHIFT controls. 107. Tuning Procedures The instrument tuning procedures follow the setting-up procedures and must be completed Master unit operator al. Set the CAVITY TUNE dial two or three numbers below the previously agreed upon starting number (setting of remote) . Place the METER switch in the AVC position. Increase the CAVITY TUNE di.lal setting until a maximum reading is indicated on the SWITCHED METER. A maximum AVC reading at this point indicates that the maser instrument is tuned to the remote instrument. bl. Establish communications with remote operator. cl. Direction find (DF) the instrument by traversing it on the tripod until the SWITCHED METER shows a maximum AVC reading. Check plumb after DF. Instruct the remote operator to direction find his instrument. dl. Switch to MEASURE and turn the METER switch to the MOD position. Check modulation levels by turning the PATTERN SELECTOR to A, B, C, and D, in turn. Announce each modulation reading to the recorder for entry in block VI of the field record and computations form (fig. 20). Request modulation readings from the remote operator and announce these to the recorder for appropriate entry on the field record and computations form. Turn the METER switch to the A VC position. el. Announce the following information to the recorder for entry in block I of the field record and computations form (fig. 20): instrument numbers, station numbers, weather conditions, and operators' names. /1. With the MEASURE-SPEAK key at MEASURE, adjust the CRT circle to a convenient reading size by using the CIRCLE AMPLITUDE, Y-AMPLITUDE, and SHAPE controls. gl. Verify the maximum CRYSTAL CURRENT reading by turning the REFLECTOR TUNE dial. With the METER switch in the AVC position, readjust the CAVITY TUNE for a maximum AVC reading on the SWITCHED METER. Inspect the circular trace on the CRT for a good clean break. If a good break cannot be obtained or the pulse appears too weak or too strong, instruct the remote unit operator to adjust the PULSE AMPLITUDE. Note. The Tellerometer system is now ready for distance measuring. AGO 10005A before a measurement is made. These procedures start with the MEASURE-SPEAK key in the SPEAK position and require coordination between the master unit and the remote unit operators. For this reason, the following instructions are arranged to insure that the proper sequence is followed. In each step, the following instructions are arranged to insure that the proper sequence is followed. In each step, the operation designated with the number 1 precedes the operation designated with the number 2. Remote unit operator a2. Set the CAVITY TUNE dial on the previously agreed upon starting number. Verify the maximum CRYSTAL CURRENT by using the REFLECTOR TUNE dial. Place the METER switch in the A VC position and watch the SWITCHED METER for a maximum reading as a signal that the master operator has tuned his set. b2. Answer the master operator's call. c2. When instructed to do so, direction find the instrument by traversing it on the tripod until the SWITCHED METER shows a maximum A VC reading. Check plumb after DF. d2. Switch to MEASURE and turn the METER switch to the MOD position. Check the modulation levels by turning the PATTERN SELECTOR to A, B, C, and D, in turn. Note the values of the modulation levels. When requested to do so, report the modulation readings to the master operator. e2. Stand by. If requested to do so, provide information to the master operator. /2. Switch the MEASURE-SPEAK key to MEASURE and stand by. g 2. If requested to do so, adjust the PULSE AMPLITUDE. 108. Operating Temperatyre a. The Tellurometer is designed to operate in temperatures ranging from -40° F to +104° F (manufacturer's estimate) . The crystals of both the master and remote units are mounted in an oven which automatically maintains operating temperature. The operation of the oven begins as soon as the power source is connected, regardless of whether the LT or the HT is on or off. b. Readings should not be taken until the OVEN CYCLE lamp has gone off for the first time. The OVEN CYCLE lamp will then blink on and off while automatically maintaining operating temperature. c. Approximately 30 minutes is required for the crystals to reach operating temperature at -40° F air temperature; less than 15 minutes is required at + 25° F air temperature. If the Tellurometer is operated in cold, extremely windy weather, a light windbreak around the instrument will reduce warmup time. 109. Measurement Procedure A Tellurometer measurement consists of one set of initial coarse readings, four sets of fine readings, and one set of final coarse readings. The readings are taken in this order and are recorded on the field record and computations form (fig. 20) as they are taken. The completed form constitutes a record of the distance measured and the system operation during one measurement. This form should be retained to make up a permanent log for the operation of Master unit opemtor a1. Switch to SPEAK and advise the remote unit operator that the initial coarse reading will be taken in the prescribed order (A+, A -, B, C, D). Switch to MEASURE, turn the PATTERN SELECTOR to position A, and read the value on the CRT to the near est division (fig 18). Announce the value to the re corder for entry in block II of the field record and computations form (fig 20). Flick the MEASURE-SPEAK key twice to indicate to the remote unit operator that the reading of the A+ pattern is complete and that a reading is desired on the next (A-) pattern. When the A-pattern appears on the CRT, read the value and announce it to the recorder for entry in block II of the field record and computations form. For the A-pattern. continue to read the clockwise edge of the break. the system. A coarse reading consists of readings on the A+, A-, B, C, and D patterns, in that order. A fine reading consists of A+ forward, A-forward, A-reverse, and A+ reverse pattern readings taken in that order for convenience in switching. If both operators know and follow this sequence for reading the patterns, the need for radiotelephone conversation will be reduced. As the reading in each pattern is completed, the master unit operator signals for a change to the next crystal setting by depressing the MEASURE-SPEAK key twice. This signal can be detected on the remote unit CRT by a change in the presentation and can be hear d on the remote unit radiotelephone as a break in the measuring tone. All readings are made at the master unit and are read in a clockwise direction at the leading edge of the break. For one complete set of readings, all of the patterns should be read without moving the CAVITY TUNE dial. If any adjustment is necessary to improve the circle break, it should be made with the REFLECTOR TUNE knob in conjunction with the PRESS PULSE sequence discussed in paragraph 107g. If a good break does not appear at this time, the leading edge of the flexing point on the circle may be used to determine a reading. The REFLECTOR TUNE knob and the CAVITY TUNE dial should be tuned simultaneously to maintain maximum AVC and CRYSTAL CURRENT readings between sets. The measuring procedures require coordination between the operators of the master and the remote units. In each step, the operation designated with the number 1 precedes the operation designated with the number 2. Remote unit operator a2. When instructed that the initial coarse readings will start, switch to MEASURE. Each time the master unit operator signals by flicking the key, switch to the next pattern frequency. The master unit operator's signal will appear as a flick on the remote unit CRT and as a break in the measuring tone on the radiotelephone. 50 AGO 10006A MruJter unit operator Flick the MEASURE-SPEAK key twice to indicate to the remote unit operator that the reading of the A pattern is complete and that a reading is desired on the next (B) pattern. Turn the PATTERN SELECTOR to position Band proceed as with the previous readings. After each read ing, flick the switch to indicate readiness to read the next pattern. When the C and D pattern readings have been com pleted, return the PATTERN SELECTOR to position A. This completes the initial coarse readings. b1. Switch to SPEAK and advise the r emote unit operator that each fine reading will be taken in the prescribed order (A+, A-, A -reverse, A+ r everse). Normally four sets of fine readings are taken. The frequency interval between sets should be the maximum allowable (i.e., 3, 5, 7, and 9) over the range of the CAVITY TUNE dial. When making the reverse r ead ings, continue to read the clockwise leading edge of the break. Announce to the remote unit operator the r emainder of the CAVITY TUNE dial settings. c1 . Adjust the CAVITY TUNE dial, if necessary, for maximum A VC readings. Check the REFLECTOR TUNE dial for maximum CRYSTAL CURRENT. An nounce MEASURE to the remote unit operator and sWitch to MEASURE. Check the circle sweep for focus, brilliance, size, shape, and circle break. If the circle break is not ap parent, adjust it with the REFLECTOR TUNE dial and PRESS PULSE. If the adjustment fails to pro duce a break communicate with the remote unit opera tor and request a high PULSE AMPLITUDE setting. d1. Take the four sets of fine readings at the previously announced CAVITY TUNE dial intervals. Flick the MEASURE-SPEAK key to signal the r emote unit operator. Announce the value read for each pattern during the measurement of each set to the recorder for entry in block III of the field record and computations form (fig. 20). After taking the A + reverse reading of each set, the master unit operator should pause momentarily before proceeding and allow the recorder to check the recorded values for possible reading errors. e1. Repeat the procedures in c1 and d1 above with different C:A VITY TUNE dial settings for the required number (four) of sets of fine readings. /1. Switch to SPEAK and advise the remote unit operator that final coarse readings will be taken. Follow the procedure in a1 above at the last CAVITY TUNE dial setting. As the readings :are made, announce the values to the recorder for entry in block IV of the field record and computations form (fig. 20). AGO 10005A Remote unit operator b2. Switch to SPEAK and wait for instructions. When advised that fine readings will be taken, turn ,' the METER switch to the A VC position and set the CAVITY TUNE dial to the announced setting. The CAVITY TUNE dial setting should be the same as that on which the initial coarse readings were taken. c2. When instructed to do so, increase or decrease the PULSE AMPLITUDE. On instructions from the master operator, switch the MEASURE-SPEAK key to MEASURE. d 2. For each of the four sets of fine readings, use the following procedure: When signaled by the master unit operator that the A + reading is complete, switch the PATTERN SELECTOR to the A-position. On the second signal from the master unit operator, depress the FORWARD-REVERSE key. When the FORWARDREVERSE key is in the REVERSE position, the master unit operator reads the A-reverse pattern. On the third signal, switch the PATTERN SELECTOR to t he A+ position. This presents the A+ reverse pattern to the master unit operator. On the fourth signal, raise the FORWARD-REVERSE key and wait for inst ructions. When instructed to do so, switch to SPEAK and advance the CAVITY TUNE dial to the next setting. e2. Follow instructions from the master operator as indicated in c2 and d 2 above. /2. Follow the procedure in a2 above at the last CAVITY TUNE dial setting. R emo te unit operatorMaster unit operator gl. Compare the interpreted initial and final coarse readings for agreement (blocks II and IV of the field record and computations form). If a significant disagreement is evident (para 113), take additional coarse readings until the error is isolated. hl. Advise the remote unit operator that the meash2. Proceed as instructed. urement is complete and give further instructions.Instructions must be explicit and thoroughly understood, since at this point the instruments will be turned off and communications severed. If at any time in tuning to a new CAVITY TUNE If at any time in tuning to a new CAVITY TUNE dial setting, communications cannot be made with the dial setting communications cannot be made with the remote unit, return to the last CAVITY TUNE dial master unit, return to the last CAVITY TUNE dial setting at which contact was made and issue instrucsetting at which contact was made and await instructions. tions. A - from the A + reading. If the A + reading 110. Computing a Tell urometer Distance is smaller than the B, C, D, and A -readings, Measurement as in figure 20, 100 is added to the A + readinga. Computations required for a Tellurometer before subtracting. distance measurement are performed in the following order: b. The difference between A+ and A-is di~ vided by 2 and the result is compared with the (1) Interpret the initial coarse readings. A + reading; 50 is added to the result, if nec (2) Interpret the fine readings. essary to keep it at approximately the same (3) Interpret the final coarse readings. value as the original A+ reading. If the values (4) Resolve the transit time in millimicro-do not compare within 4 millimicroseconds, the seconds from correctly interpreted coarse measurements must be reobserved. In pattern differences. figure 20, this value (03.0) is within 2 milli (5) Compute the slope distance in meters microseconds of the A + reading (05), which is from a transit time in millimicrosatisfactory. seconds. 112 . Interpreting the Fine Readings (6) Reduce the slope distance to a hori {Block Ill) zontal sea level distance in meters. After the fine readings are taken and r e b. Tellurometer distance measurements are corded in block III, the mean differences andnormally computed at the master station before the mean fine reading are computed. In the ex party personnel depart for subsequent survey ample below, one set of the fine readings inoperations. This permits the verification of the figure 20, block III, is meaned: distance determined by map scaling and the resolution of ambiguous pattern differences if Remote Set dial Forward Reverse they occur. Figure 20 illustrates the recording 1 3 A+ 05 A+ 59of readings on a field record and computations A - 99 A -51 form (DA Form 5-139) and is used as a refer ence for the discussions on computations in 06 08 paragraphs 111 through 117. 06 + 08 = 14 -+-2 = 07 mean difference 07 -+-2 = 3.50 mean fine reading 111 . Interpreting the In itial Coarse Readings A+ (initial coarse) = 05.00 (block II) (Block II) Mean fine reading = 03.50 a. The phase difference is determined by subtracting the coarse readings B , C, D, and Zeroing error 1.50 millimicroseconds AGO 10005A 52 FIELD RECORD AND COMPUTATIONS· TELLUROMETER (TB ENG 23) BLOCK I • STATION DATA HEIGHT STATION INST. t«>. OPERATOR WEATHER: METERS CL£11~-W/IRM MASTER : STERL lNG I I~lj.9. / ~38 LECLAIR RECORDER : BVRK .REMOTE : IIPAci-IE 2j~/.,?. C. 2..3"1 PoLL.ARD APPROX . DIS.~ MILES ~. 3 METERS 351JO 3J HEIGHT DIFF:(I)8(2).3'". SJ4 SUM OFHEIGHTS(I)+-(2l.f,/. 7 ~JMEAN HEIGHT (4) ·H2l l/-30. 5' M BLOCK II .. INITIAL COARSE READINGS BLOCK IV .. FINAL COARSE READINGS A+ OS A+ OS A+ 05 A+ OS A+ 07 A+ 07 A+ 07 A+ 07 B c D A 78 t-5 :lf. B 7'1 c D ~s A 'I"' '~ DIFF DIFF 1/.0 DIFF DIFF OIFF DIFF DIFF DIFF 2.7 5'1 !!.f!.--2 :J..f "'-/ 82.. ~ "'"' COMPARE WITH A+ COMPARE WITH A+ · 03. 0 oJ~. o BLOCK Ill .. FINE READINGS BLOCK V .. TRANSIT TIME (Ill, IV & X) ~EIIIOTE SET A FafNARO REVERSE MEAN DIFF APPROX DIS MILES(X) 0 0 0 ojo o DIAL JoJO I ~:: ::::::::: + OS sq A +,B DIFF 8 0 0 OjO 0 :::::: :::::::::::;::111111!:: •:: : FINA L J:z. COARSE A+,C DIFF 0 [:H:::: 3 -qq 51 ::::::••• ::••••::•: H• Jf I o1o 0 r.. :::::, 03. lf'l 3(,p 3h BLOCK VII .. SLOPE DISTANCE, METERS BLOCK IX .. SEA LEVEL DISTANCE METERS I LOG CORRECTED TRANSITTIME(ll) 11 Ln~1 ~3&~1 I LOG SLOPE DISTANCE METERSOlnl 3 !ss.z12'1oh 2 LOG 1/2 V/N METERS 9 I 17!! 6!!09 2 LOG COS VERTICAL ANGLE (lliiJ I 9 !99'1!9772 (1)+(2) LOG HORIZONTAL3 LOG SLOPE DISTANCE METERS( I)+{~ 3 3 'ss:z. :J9o~o 3 !ss.z1:1.{,78 DISTANCE METERS 4 LOG SEA LEVEL COEFFlCIENTOOI 1111111./l.l/1/11/11/1////' ..... •,,,,,:g•:•:•: ::: ::::::•::::::: :u:u:@.!li[i//1/.lli...//i " !'f'J"'j'172_1j:H:!: !!!:! ::U:::Ji:>:n::H / /HH HU: • ~ (3l+ (4) LOG SEA LEVEL DISTANCE METERS 3!55~~4JDS BLOCK VIII • VERTICAL ANGLE 6 SEA LEVEL DISTANCE METERS 3Shh. 4.J.lf IN HEIGHT A+ C Diff 4 I 0 0·0 0 T "thocomporew1 A+C Ditf consider Readings A+ D Diff (block nz:l ... Mean fine reading (blockml 8 2 0 0·0 0 3·4 4 . To com.pare Wl~h A+D 01ff cons1der + Use this value to compare with A+ D Diff Unresolved transit time (block ml 0 2 4 8 0 3·4 4 Resolved transit time (blockm.l 0 2 3 8 0 3i4 4 ~~~,%~,44 23ao3.14J 13 3. 4 ~5803A4 480344 (:~~~~: rd. o l" ' Pes,,.,/ ~.l~ti'V E /Yl~a. urc,l... ~a...ft:l' 511-.lc.l.. Figure 28. Page of field notebook. check all entries and initial each numbered a permanent record. Numerals and decimal points should be legible and distinct so that page. Data pertaining to different survey opel·a tions should not be recorded on the same page.only one interpretation of the data is possible. The recorder accompanies the instrument opc. Erasures are not permitted in the field erator and records the data in the field notenotebook. When incorrect data has been entered book as. it is announced to him; he then reads in the notebook, it is corrected by drawing a it back to insure the ,correctness of the data. single line through the incorrect data and enField data are entered directly in the notebook tering the correct data immediately above the and not on scraps of paper for later transcrip incorrect data. When a page is filled with data tion. As the field data entries are made in the that will not be used because of a change in notebook, the recorder computes and records plans, etc., the page is crossed out by drawing mean values and, for ease of identification, endiagonal lines between opposite corners of the ciTcles the data that is. to be furnished to the page and printing the word VOID in large let computers as they request it. Station descripters across the page. tions, sketches, and any necessary remarks are d. The format for recording field data is il entered in the notebook as time permits during the progress of survey operations. To minimize lustrated in the chapters in which the various instruments and survey methods are discussed. recording eTrors, the chief of party should AGO 10005A 70 Section II. AIMING CIRCLE M2 145. General Description ments are recorded on graduated scales andmicrometers. The aiming circle has two hori The aiming circle M2 (fig. 29) is a small,lightweight instrument that is used in the firing zontal rotating motions. The upper (recording)battery ,and in artillery survey operations exemotion changes the readings of the azimuthcuted to an accuracy of 1:500. Basically, it conscales of the instrument; the lower (nonrecordsists of a low-power, fixed-focus telescope ing) motion does not. The aiming circle ismounted on a body that permits unlimited horiequipp-ed with leveling screws, level vials, and azontal and limited vertical rotation of the telemagnetic compass. The instrument is mountedscope. Hortzontal and vertical an1rle measure-on a base plate that serves as the base of the AI M ING CIRCLE LAMP HOL DERAND REMOVER COVER FORAIMING CIRCLE PLUMB } BOB Figure 2 9. Aiming circle with accessory equipment. AGO 10005A 71 carrying case and is also used in mounting the the body assembly, the worm housing, and the base plate assembly (fig. 30). instrument on a tripod. The aiming circle M2 consists of the aiming circle body and the aca. Telescope Body Assembly. The telescopecessory equipment. The aiming circle without8 body assembly consists of the optical system,accessory equipment (para 147) weighs the vertical level vial, the reflector, and a filter pounds 2 ounces and with accessory equipment for solar observations. weighs 22 pounds. (1) Optical system. A 4-power, fixed-focus 146. Aiming Circle Body telescope forms the optical system of the aiming circle. The telescope reticle The aiming circle body is made up of four is formed by a glass etched with aprincipal parts-the telescope body assembly, FOUR MAJOR PARTS OF THE AIMING CIRCLE BODY RLESCOPE BODY Cutaway drawing of aiming circle showing composite parts. Figure 90. AGO 10005A 72 7060504030 20-= 10 20 30 40 5060 70 80 10 -= ,,, Itit,, It I I It,, 1 1 1 1 1 1 1 11 I' 1 1 11 11 -10 80 70 60 50 40 30 20 10 -20 -30 -40 =-50 -60 -7o F igure 81. T elescope reticle. horizontal and a vertical crossline intersecting at the center of the telescope. These crosslines are graduated at 5-mil intervals from the center. The gra duations range from 0 to 85 mils and are numbered every 10 mils (fig. 31) . These graduations are used to measure relatively small horizontal and vertical deviations from a reference line (e.g., in a high-burst registration). The telescope eyepiece (fig. 32) is inclined upward at an angle of 45° from the axis of the telescope to permit the observer to look down into the telescope while standing erect. Locat ed on top of the inclined portion of the telescope is a machined slot for attaching the instrument light. The objective end of the telescope is beveled to form a permanent sunshade. (2) T elescope level vuu. The telescope level vial is located on the left side of the telescope. This level is used to establish the horizontal axis of the telescope in a true horizontal plane. The lugs supporting the telescope level vial are shaped to form an open sight for approximate alinement of the telescope on a station. The telescope level is not used in artillery survey. (3) R eflector . The reflector is a plastic signal post mounted on top of the telescope at the vertical axis of the instrument. The reflector is used as an aim- F igure 82. Aiming Circle M 2. AGo 1ooosA 73 ing point for other instruments sighttical angles are read in two p,arts; the ing on the aiming circle M2. At night hundreds of mils are read from the the reflector can be illuminated exterelevation scale, and the tens and units of mils are read from the elevation nally by use of the instrument light. micrometer scale. The elevation scale ( 4) Filter. A filter is provided for viewing is graduated and numbered in 100-milthe sun directly when astronomic obincrements from minus 400 mils to servations are being made. The filter plus 800 mils. The plus and minusis slipped onto the eyepiece end of the symbols are not shown, but the minustelescope when the sun is being obnumerals are printed in red and theserved and is attached to the side of plus numerals are printed in black.the telescope body when not in use. The elevation micrometer scale is graduated in 1-mil increments from 0 b. Body Assembly. The body assembly conto 100 mils. The scales are numberedsists of the azimuth and elevation worm every 10 mils from left to right inmechanisms; the magnetic compass, with retiblack numerals and from right to leftcle and needle actuating lever; and two horiin red numerals. The red numerals onzontal plate levels. the elevation micrometer scale are ( 1) Azimuth mechanism. The azimuth used in conjunction with the red numechanism (upper motion) of the inmerals on the elevation scale. The strument has both a fast and a slow black numerals on the micrometermotion. Lateral movement of the aziscale are used with the black numeralsmuth knob permits fast motion. Hori on the elevation scale. zontal angles are read in two parts; (3) Magnetic compass. The magnetic comthe hundreds of mils are read from the pass is located in the oblong recess inazimuth scale, and the tens and units the top of the body assembly. The of mils are read from the azimuth magnetic needle is limited in move micrometer. The azimuth scale is graduated in 100-mil increments from ment to approximately 11 ° of arc and 0 to 6,400 mils and is numbered every is provided with copper dampers to aid in settling the needle quickly. A200 mils. The portion of the azimuth small glass magnifier and a reticle scale from 3,200 mils through 6,400 mils has a second scale numbered in with three vertical etched lines are at one end of the recess to a id in aliningred from 0 to 3,200 below the primary the south end of the needle. On the opscale. The graduations of the primary posite end of the recess is a lever(upper) scale are used for survey. The which locks or unlocks the magneticsecond (lower) scale is used for laying needle. When the lever is in a vertical the weapons of the firing battery. Thi s lower scale is not used in survey. The position, the needle is locked. When the lever is turned either right or left azimuth micrometer scale is located on the azimuth knob. It is graduated in to the horizontal position, the needle is unlocked. 1-mil increments from 0 to 100 mils and is numbered every 10 mils. (4) Horizontal plate levels. Located on the (2) Elevation mechanism. The elevation body assembly at the left side of the magnetic needle recess are two hori mechanism of the aiming circle is zontal plate levels; one is a circularsimilar to the azimuth slow motion level vial that may be used for roughmechanism. Stop rings in the mechleveling of the instrument, the other is anism prevent the telescope from a tubular level vial that is used to acstriking the body assembly when it is curately level the instrument.depressed. Vertical angles from mi c. Worm Housing. The worm housing is that nus 440 mils to plus 805 mils can be portion of the aiming circle below the azimuthmeasured with the aiming circle. Ver- AGO 10005A 74 LAMP HOLDER AND REMOVER Figure 99 . scale and above the base plate. It contains the worm gear of the orienting (lower or nonrecording) motion, the leveling screws, and the spring plate. The orienting knob controlling the nonrecording motion of the aiming circle is similar in operation to the azimuth (recording) motion of the aiming circle in that lateral movement of one orienting knob permits fast movement in the orienting motion of the aiming circle. The two orienting knobs should be used simultaneously for slow movement of the orienting motion. Caps are provided for the orienting knobs to preclude use of the orienting AGO 10005A HAND LIGHT CANVAS COVER A ccessory k:it. motion by mistake. Each of the three leveling scr ews is fitted into a threaded socket in the worm housing and attached to the base plate by means of the spring plate. d. Base Plate Assembly. The base plate assembly is the base of the instrument when it is mounted on the tripod and it also serves as the base of the carrying case. It is a flat circular plate to which the instrument is attached by the spring plate. A rectangular shaped notation pad is located on the base plate and is used for recording the declination constant and the ver tical ai;J.gle correction. An instrument-fixing when it is used to aline the instrument over a screw is threaded into a socket on the underside point on the ground. When the plumb bob is not in use, it is stored in a loop in the canvas of the base plate assembly to attach the instrucover of the accessory kit. ment to the tripod. The socket is kept clean and free of obstructions by a spring-loaded cover e. Lampholder and Remover. The lampholder that remains closed when the instrument is not and remover is a small, rubber tubular acces -I attached to the tripod. The base plate is fitted sory in which spare lamp bulbs are stored; it with a rubber gasket that makes a watertight can also be used for removing burned out bulbs seal when the cover is latched to it. from their sockets. 147. Aiming Circle Accessory Equipment f. Carrying Case Cover. The cover of the carrying case is a lightweight dome-shaped The accessory equipment for the aiming ciraluminum cover that can be clamped to thecle consists of the tripod, the carrying case base plate to provide a waterproof case for thecover, and the accessory kit. The accessory kit instrument. The cover is provided with a carry (fig. 33) contains the instrument light, plumb ing strap and two strong clamps for securing bob, lampholder and remover, and backplate the cover to the base plate. and canvas cover. a. Tripod. The tripod (fig. 29) has three tele148. Setting Up the Aiming Circle M2 scoping legs, an aluminum head and cover, and a. Setting Up the Tripod. The procedure for a carrying strap. The legs are adjusted for setting up the tripod is as follows: length and held in place by means of leg clamp wing screws. The leg hinges at the tripod head (1) Upend the tripod and place the tripod are adjusted for friction by clamping screws. head on the toe of the shoe. Unbuckle The ends of the legs of the tripod are fitted with the restraining strap and secure the an aluminum boot and a bronze spike for ease strap around the leg to which it is in embedding the legs in the ground. A strap attached. holds the legs together in the retracted position. (2) Loosen the leg clamp wing screws and An adjustable strap is provided for carrying extend the tripod legs to the desired the tripod when the legs are retracted and length. Tighten the leg clamp wing strapped together. screws. b. Backplate and Co ver. The backplate and (3) Turn the tripod to its upright position cover (fig. 33) serves as the carrying case for and test the adjustment of each trit he instrument light, plumb bob, and lamppod leg by elevating each leg, in turn, holder and remover. It is fastened to one of the to a horizontal position and then retripod legs by two clamps. leasing it. If the leg is properly adjusted, it should fall to about 45 ° and c. Instrument Light. The instrument light stop. If it does not, the tripod legconsists of a battery tube containing two flashshould be adjusted by tightening orlight batteries and two flexible cords. One of loosening the tripod clamping nut. these cords carries the current to the telescope The test should be repeated until sucthrough a lamp bracket assembly that fits into cessful. a machined slot on top of the telescope assembly. The other cord is attached to a hand light (4) Spread the legs and place the tripod assembly for general illumination around the over the station to be occupied, with ins trument (leveling and reading the scales) one leg approximately bisecting the and to illuminate the reflector. The light intenangle(s) to be measured. The head of sity is regulated by a rheostat located on the the tripod should be set up at a height end of the battery tube. The battery tube is which will place the telescope at a fastened to the backplate by means of a clamp. convenient height for the operator. d. Plumb Bob. The plumb bob is suspended (5) Insert the plug-in sleeve of the plumb from a hook in the instrument-fixing screw bob into the instrument-fixing screw AGO 10005A 76 ---------------------------------------------------------~ and extend the plumb bob so that it will hang about an inch above the station. Center the tripod approximately over the station. (6) Firmly embed the tripod legs, making sure that the plumb pob is within onehalf inch (laterally) of being centered over the station and that the tripod head is approximately level when the legs are embedded. (7) Remove the tripod head cover and secure it to the tripod leg. b. Attaching the Aiming Circle to the Tripod. To attach the aiming circle to the tripods open the spring-loaded cover on the base plate and thTead the tnstrument-fixing screw into the socket until the aiming circle is firmly attached to the tripod. Unsnap the aiming circle cover latches, remove the cover, and hang it on the tripod head cover. c. Plumbing and L eveling the Aiming Circle. The procedure for plumbing and leveling the aiming circle is as follows: (1) Loosen the fixing screw slightly and carefully move the instrument around on the head of the tripod until the point of the plumb bob is centered exactly over the station. (2) Tighten the instrument to the tripod head, making sure that the point of the plumb bob remains centered over the station. Caution: Excessive tightening of the fixing screw will bend the slotted arm and damage the tripod head. (3) Loosen the leveling screws to expose sufficient threads (%" to %") on the three screws to permit the instrument to be leveled. Rotate the instrument until the axis of the tubular level is paTallel to any two of the three leveling screws. Center the bubble by using these two leveling screws. Grasp the leveling screws. between the thumb and forefinger of each hand and turn the screws simultaneously so that the thumbs of both hands move either toward each other or away from each AGO 10005 A other at the same time. This movement tightens one screw as it loosens, the other. The bubble always moves .in the same direction as the left thumb. (4) Rotate the instrument 1,600 mils; this places one end of the plate level over the third leveling screw. Using this, screw, center the bubble. (5) Return the instrument to the first position ((3) above) and again center the bubble. (6) Return the instrument to the second position ( (4) above) and again center the bubble. (7) Repeat (5) and (6) above until the bubble remains centered in both positions. (8) Rotate the instrument 3,200 mils from the first position. If the bubble remains centered in this position, rotate the instrument 3,200 mils from the second position. If the bubble remains centered in this position, rotate the instrument throughout 6,400 mils. The bubble should remain centered; if it does, the instrument is level. (9) If the bubble is not centered when the instrument is rotated 3,200 mils from the first position ((8) above), the level vial is out of adjustment. To compensate, move the bubble halfway back to the center of the level vial, using the same leveling screws that were used for the first position. Rotate the instrument 3,200 mils from the second position and move the bubble halfway back to the center of the level vial, using the one remaining leveling screw. The instrument is now level, and the bubble will come to rest in its vial at the same offcenter position regardless of the direction in which the instrument is pointed. The level vial should be adjusted at the first opportunity. 149. Taking Down the Aiming Circle The procedure for taking down the aiming circle is as follows: f. With the upper slow motion, bring thea. Tighten the leveling screws to their stops. crosslines. exactly to the point, rotating the b. Check to insure that the magnetic needle instrument from left to right. is locked. g. Read and record the value of the angle onc. Cover the level vials. the azimuth and micrometer scales to the d. Place the azimuth knob over the notation nearest 0.5 mil.pad. h. With this value still on the scales, repeat e. Unhook the plumb bob and replace it in c through f above. the backplate cover. Close the backplate cover. i. Read and record the accumulated value off. Place the carrying case cover over the two measurements of the angle to the nearestaiming circle and latch the cover locks. 0.5 mil. g. Unscrew the instrument-fixing screw and j. Divide the accumulated value in i above byremove the instrument from the tripod. 2. If the accumulated value of the angle (i h. Replace the tripod head cover. above) is,smaller than the first value (g above), i. Collapse the tripod legs and tighten the add 6,400 to the accumulated value before diwing screws. viding by 2. The mean value determined should j . Strap the tripod legs together. agree with the first value within 0.5 mil; if not, the angle must be remeasured. 150. Measuring Horizontal Angles In artillery survey, horizontal angles are 151. Measuring Vertical Angles measured at the occupied station in a clockThe vertical angle to a point is measured wise direction from the rear station to the forfrom the horizontal plane passing through the ward station. Pointings for horizontal angles horizontal axis of the telescope of the instruare always made to the lowest visible point at ment. The vertical angle is expressed as plus or the rear and forward stations. In sighting on a minus, depending on whether the point is above station, the vertical crossline is placed so that (plus) or below (minus) the horizontal plane. it bisects the station marker. When angles are Usually, the vertical angle is measured each measured with the aiming circle, two repetitime a horizontal angle is measured. Vertical tions of the angle are taken and the accumuangles are measured twice, and the mean value lated value is divided by 2 to determine the is determined. Vertical angles, if possible, are mean value of the angle. The procedure for measured to the height of instrument (HI) at measuring horizontal angles is as follows: each forward station. The height of instrument a. Set up and level the aiming circle. is determined by measurement on a ranging pole. If the instrument operator consistently b. Zero the azimuth and micrometer scales. sets the instrument up at approximately the c. Sight approximately on the rear station by same height, then the same height of instruusing the lower (nonrecording) fast motion. ment may be used throughout the fieldwork for measuring vertical angles. The procedure for d. Place the crossline exactly on the rear sta tion by using the lower slow motion. The last measuring vertical angles is as follows: motion coming onto the station should be from a. Set up and level the aiming circle. left to right to reduce backlash due to the play b. When the first measurement of the horiin the worm gear mechanism. Check the azizontal angle is completed (para 150g), elevatemuth and micrometer scales to insure that they or depress the telescope to place the horizontalare still at zero. Close the orienting knob crossline at the height of instrument on thecovers. forward station. e. With the upper (recording) fast motion, c. Read and record the value of the vertical rotate the aiming circle to bring the crosslines angle to the nearest 0.5 mil. If the black nu near the forward station, but keep them to merals are used, the vertical angle is plus; ifthe left of the station. AGO 10005A 78 the red numerals are used, the vertical angle each azimuth mark and compare theis minus. mean of each with the correspondingknown vertical angle. Determine thed. After the second measurement of the horidifferences ( +). If the differences zontal angle is completed (para 150i), measurethe vertical angle a second time. agree within 1 mil of each other, determine the mean difference.to 0.1 mil e. Determine the mean vertical angle by addand record this value on the notationing the first and second readings of the vertipad with the declination constantcal angle and dividing the sum by 2. The mean (e.g., VAC + 1.6).vertical angle should agree with the first readNote. If the differences do not agree withing within 0.5 mil. in 1 mil, repeat (1) through (3) above. Example: 152. Determining Vertical Angle Correction +23.0 mils = known vertical angleTo obtain correct measurements of vertical to azimuth mark 1angles with the aiming circle, the horizontal +21.5 mils = mean measured verticalaxis of the telescope must lie in a true horiangle to azimuth markzontal plane when the elevation scale is at zero. 1If it does not, a vertical angle correction (VAC) + 1.5 mils = correction to bring must be determined and applied to each vertimeasured vertical angle cal angle measured with the aiming circle. A to known vertical anglevertical angle correction is determined at the -9.0 mils = known vertical angle tosame time that the declination constant is deazimuth mark 2termined. Two methods may be used to deter -10.8 mils = mean measured verticalmine the vertical angle correction-the comparangle to azimuth markison method and the alternate method. 2 a. Det ermination of Vertical Angle Correc+ 1.8 mils = correction to bring tion by Comparison Method. The vertical angle measured vertical anglebetween two points is measured with the aiming to known vertical anglecircle and compared with the correct vertical + 1.5 mils = correction at azimuthangle between those points. The correct vertical mark 1angle can be determined by measurement with + 1.8 mils = correction at azimutha theodolite or by computation, using the dismark 2tance and difference in height between the + 3.3 + 2 = + 1.6 mils =mean verpoints. Whenever a declination station is estabtical angle correctionlished, the vertical angle to each azimuth mark b. Determination of V ertioal Angle Correc should be determined so that the vertical angle correction can be checked at the time the aimtion by Alternate M ethod. Two stations are es tablished approximately 100 meters apart anding circle is declinated. The vertkal angle corproperly marked. It is not necessary to knowrection is determined by the comparison meth the coordinates and height of the s.tations orod as follows: the distance between them. The aiming circle (1) After determining the declination conis set up at one of the stations, and the heightstant, check the level of the instru of instrument is measured and marked on a ment. Measure the vertical angle to range pole with a pencil. The range pole iseach azimuth mark to which the verplaced vertically over the second station. Thetical angle is known. Read and record vertical angle to the mark on the range polethe values to the nearest 0.5 mil. is t hen measured with the aiming circle. The (2) Verify the level of the instrument and aiming circle is then moved to the second stameasure the vertical angle to each tion and set up. The height of instrument atazimuth mark a second time. Record the second station is marked on the range pole. the values. The pole is then set up over the first station, ( 3) Mean the vertical angles measured to and the vertical angle from the second station AGO !0005A 79 to the first station is measured. The vertical netic needle. The procedure for orienting on a angles measured at the two stations are comrequired azimuth is as follows: pared. If they are numerically equal but have a. Set up and level the aiming circle in the opposite signs (e.g., + 7.0 and -7.0), the inprescribed manner. strument is in correct adjustment and the verb. Using the upper motion, set the declina tical angle correction is zero. If the values are tion constant on the scales of the instrument. not numerically equal, a vertical angle correc tion must be determined. The correction is c. Release the magnetic needle and center it, using the lower motion. numerically equal to one-half of the algebraic sum of the two angles. Th-e sign of the oorrrec.d. Lock t he magnetic needle. tion is opposite to the sign of the algebrai c sum e. Using the upper motion, set the requiredof the two angles. For example, if one angle grid azimuth on the scales of the instrument. were +22.0 mils and the other were -24.0 The scope of the instrument is now oriented on mils, the vertical angle correction would be the required azimuth. +1.0 mil. The vertical angle correction must be applied to all vertical angle measurements 155. Care of the Aiming Circle made with the aiming circle. Proper care of an instrument will prolong its life and insuTe better results to the user. 153. Determining Grid Azimuth With the Aiming Circle Listed below are several precautions which should be observed while the aiming circle is The magnetic compass of a declinated aiming being used. ciTcle can be used to determine a grid azimuth. The procedure for determining a grid azimuth a. Screw Threads. To prevent damage to the is as follows: screw threads, do not tighten the adjusting, a. Set up and level the aiming circle in the clamping, or leveling screws beyond a snug contact. prescribed manner. b. Using the upper motion, set the declination b. Lenses. The lenses should be cleaned only constant on the scales of the instrument. with a camel's-hair brush and lens tissue. The brush should be used fiTst to remove any dust c. Release the magnetic needle and center it, or other abrasive material from the lens, and using the lower motion. then the lens should be cleaned with the lens tissue. Any smudge spots remaining on the lens d. Lock the magnetic needle. after the lens tissue is used can be removed e. Using the upper motion, rotate the instruby slightly moistening the spot and again ment and sight on the desired point. cleaning with the lens tissue. Care should be f. Read and record the measured grid azitaken not to scratch the lens or remove the bluish coating. The bluish coating reduces themuth as indicated on the scales of the aiming glare for t he observer. circle to the nearest 0.5 mil. c. Tripod Head. The tripod head should be g. Repeat the procedure and determine the wiped clean of dirt and moisture and shouldgrid azimuth a second time. If the two azimuth be examined for nicks or burrs. before thedeterminations agree within 2 mils, mean and instrument is attached to the tripod. record the measured grid azimuth to the near est 0.1 mil. If they do not agree, repeat the end. Magnetic N eedle. The magnetic needle tire procedure. should be locked when not in use. e. A zimuth Knob. The azimuth knob should 154. Orienting the Aiming Circle by be positioned over the notation pad before the Magnetic Compass on a instrument is put in its case. Required Azimuth f. Worm Gears. Movement of the worm gearsA declinated aiming circle can be oriented should never be forced. In disengaging the faston a required grid azimuth by use of the mag- AGO 100 05A 80 motion, of the azimuth mechanism, be sure that cal crossline moves off the point as the telethe gear is free before the instrument is roscope is elevated or depressed, the instrumenttated. To reengage the worm gear, move the should be turned in for repair. instrument back and forth slightly until thegear of the azimuth mechanism meshes with c. Micrometer Adjustment Checks. The onlythat of the lower (nonrecording) motion. adjustments that may be made by using unitpersonnel are the adjustments of the microme g. Lubrication. The aiming circle should not ters so that they read zero when the mainbe lubricated by unit personnel. All parts rescales with which they are associated read zero. quiring lubrication are enclosed and should belubricated only by ordnance instrument repair (1) Ckecking and adjusting the azinnuthpersonnel. The instrument should be checked micrometer. The azimuth micrometerperiodically by an ordnance maintenance unit. is checked and adjusted as follows: (a) Set the zero of the azimuth scaleh. Cleaning. The instrument should be kept opposite the index mark. clean and dry. Metal parts should be cleaned (b) If the zero of the azimuth micromeof grease and oil with mineral spirits paint thinner and then wiped dry. Care must be ter is opposite the index, no adjustment is necessary. If the zero is not taken to insure that the threads of the leveling opposite the index, loosen the screws screws are clean and turn smoothly. The pol ished surfaces should be given a thin coat of on the end of the azimuth knob and slip the micrometer scale until thelight grade aircraft instrument lubricating oil zero is opposite the index. to prevent rust. Electrical parts should becleaned with trichloroethylene. Rubber parts, (c) Hold both the azimuth knob and theother than electrical parts, should be cleaned micrometer scale in position and with warm soapy water. After the rubber parts tighten the azimuth knob screws. are dry, a coating of powdered technical tal(d) Check to insure that the zero of bothcum should be used to preserve the rubber. the azimuth scale and the micromeCanvas shoulrl be cleaned with a dry brush or ter scale are still opposite their reby scrubbing with a brush and water. spective index marks after thescrews are tightened. 156. Maintenance Checks and Adjustments (2) Checking and adjusting the elevationMaintenance checks should be made as demicrometer. The elevation micrometerscribed in a through e below. If any check, is checked and adjusted as follows: other than the micrometer adjustment check in (a) Set the zero of the elevation scalec below, indicates that adjustment is necessary, opposite the index mark.the aiming circle should be turned in to the sup (b) Ifthe zero of the elevation micromeporting ordnance maintenance unit for repah;. ter is opposite the index, no adjustThe checks in a through e below should be per~ ment is necessary. If the zero is notf ormed before the instrument is used. opposite the index, loosen the screws a. Level Vial Check. After the aiming circle on the end of the elevation knob andhas been set up and leveled, rotate the instruslip the elevation micrometer scalement through 6,400 mils. If the bubbles in the until the zero is opposite the index. horizontal plate level vials (circular and tubu(c) Hold both the elevation knob andlar ) do not remain centered, the instrument the micrometer scale in positionshould be turned in for repair at the first opporand tighten the micrometer knobtunity. screws. (d) Check to insure that the zero of b. Tilted Reticle Check. After the aiming both the elevation scale and the micircle has been set up and leveled, place the crometer scale are still oppositevertical crossline on some well-defined point. their respective index marks, afterElevate and depress the telescope. If the vertithe screws are tightened. AGO 10005A 81 d. Level Line Check. The purpose of the level check must be performed before a vertical angle is measured with the aiming circle. line check is to determine whether correct values are obtained when vertical angles are e. Magnetic Needle Check. To check the magnetic needle, set up and level the aiming circle. measured with the aiming circle. If correct vertical angle values are not obtained with the inRelease the magnetic needle and center it in the reticle of the magnetic needle magnifier. To strument and there is not adequate time to turn test the needle for sluggishness, move an ironthe instrument in for repair, a vertical angle correction should be determined. The per'or steel object back and forth in front of the aiming circle to cause the needle to move on formance of the level line check and the proits pivot. Permit the needle to settle. If the cedure for determining a vertical angle correcneedle does not return to center in the reticle, tion are discussed in detail in paragraph 152. the instrument should be turned in for Tepair. After the elevation micrometer check (c(2} This check should be performed prior to using above) has been performed and any necessary the magnetic needle to establish a direction or to orient the :i nstrument. adjustments have been made, the level line Section Ill. THEODOLITE, T16 (1) Horizontal circle clamp. The hori 157. General zontal circle clamp is located on the The T16 theodolite (fig. 34) is a compact, upper part of the horizontal circle lightweight, dustproof, optical-reading, direchousing and is beneath the telescope tion-type instrument equipped with a horizontal eyepiece when the telescope is in the circle (repeater) clamp. It is used to measure direct position. This clamp is used both horizontal and vertical angles for artillery by the operator to lock the horizontal fifth-order survey. The horizontal and vertical plate to the alidade in any given posi-~ scales of the theodolite are inclosed and are tion for orienting the ins.trument. ~ read by means of a built-in optical s.ystem. The (2) Horizontal clamping screw. The hori scales, graduated in mils, can be read directly zontal clamping screw is located on to 0.2 mil and by estimation to the nearest 0.1 the side of the horizontal circle hous.mil. The scales may be illuminated by either ing. This control locks the afidade insunlight or artificial light. any desired position about its verti cal axis. 158. Nomenclature of the T16 Theodolite (3) Horizontal tangent screw. The hori a. Tribrach. The tribrach is that part of the zontal tangent screw is located adjatheodolite which contains the three leveling cent to the horizontal clamping screw screws, and the circular level. The leveling on the side of the horizontal ciTcle screws are completely inclosed and dustproof. housing. This control provides preThe tribrach is detachable from the theodolite cision adjustment in the horizontal and is secured to the theodolite by three tapered positioning of the telescope. locking wedges controlled by the tribrach clamp c. Alidade. The alidade, the upper part oflever. the theodolite, includes the telescope and b. Horizontal Circle Housing. The horizontal microscope assemblies and the vertical circle circle housing assembly contains the horizontal assembly. Located on the alidade are the folcircle; the vertical axis assembly; the receplowing:tacles, contacts, and connections for electric ilplate (1) Levels. The theodolite has a for lumination; and the three spike feet level and vertical circle level (splitsecuring the theodolite to the tribrach. The folbubble) in addition to the circularlowing controls, are located on the horizontal level on the tribrach. The plate levelcircle housing: 4 AGO 10005A 82 TELESCOPE VERTICAL EYEPI RETICLE ILLUMINATING CLAMPINGMICROSCOPE SCREW MIRROR CONTROL KNOB YEPIECE COLLIMATIONLEVEL MIRROR UN SHADE 28-POWERTELESCOPE VERTICAL .A-=------OPTICAL TANGENT PLUMB SCREW EYE PIECE ;:------TRIBRACHCLAMP LEVELING SCREWS HORIZONTAL CIRCULAR HORIZONTAL HORIZONTAL CIRCLE LEVEL CLAMPING TANGENT CLAMP SCREW SCREW Figure 94. T 16 theodolite. is located at the bottom of the opening the image, by rotating the knurledbetween the standards on the alidade focusing ring. Two horizontal pulland is graduated to aid the operator action screws are provided for corin the precise leveling of the instrurecting the horizontal collimationment. The vertical circle level is comerror. A knob located on top of thepletely built in and is located adjacent telescope controls a small mirror into the vertical circle. s.ide the telescope for illuminating the (2) Telescope. The 28-power telescope of reticle when electric illumination is the T16 theodolite can be rotated verused. tically about the horizontal axis of the (3) Circle-reading microscope. Attachedtheodolite. Objects appear inverted to the telescope is a microscope forwhen viewed through the telescope. viewing the images of the horizontalThe reticle of the telescope is etched and vertical circles. A segment ofon glass and consists of horizontal both circles is presented in the microand vertical crosslines, a solar circle scope, with the horizontal circlefor making pointings on the sun, and (marked "Az") appearing below thestadia lines. The reticle crosslines vertical circle (marked "V"). ·Theare focused by rotating the eyepiece; image of the circles is brought into AGO 10005A 83 focus by rotating the knurled microports by twp clamping levers. A desiccant is located in the base plate. A padded wooden scope eyepiece. box is also furnished for transporting the (4) Illumination mirror. A tilting mirror t theodolite in its case. is located on the side of the standard below the vertical circle for illuminating the horizontal and vertical circles. The intensity of the light on the circles can be adjusted by rotating and tilting the mirror until proper lighting is achieved. For artificial illumination, this mirror is removed and replaced by a lamp assembly. (5) Vertical clamping screw. The vertical clamping screw is located on the standard opposite the vertical circle. This control allows the telescope to be rotated vertically about its axis or to be locked in a fixed vertical posdtion. (6) Vertical tangent screw. The vertical tangent screw is located on the lower portion of the same standard as the vertical clamping screw. This control provides precision adjustment in the vertical positioning of the telescope. (7) Collimation level tangent screw. The collimation level tangent screw is located below the vertical circle and on the same standard. This control is used for precise leveling of the vertical circle level (split bubqle) by bringing the image of the ends of this bubble into coincidence. A tilting mirror is provided above the vertical circle for viewing the position of the bubble. (8) Optical plumb. An optical plumb system is provided on the theodolite for centering the instrument over a station. The optical plumb is a small prismatic telescope that contains either a small circle or crosslines as a reticle, depending on the model. The focus. of the optical plumb telescope is adjusted by rotating the knurled eyepiece located in the base of the alidade. d. Carrying Case. The carrying case for the Tl6 theodolite consists of a base plate and a steel, dome-shaped hood. When mounted in the base, the instrument rests on supports by means of four studs and is locked to the sup e. Accessory Equipment. (1) Electric illumination device. An electric illumination device is issued with the T16 theodolite. In the lower housing of the theodolite that fits into the tribrach is a socket for a connector plug from the battery case. A second socket in the horizontal circle hous.ing is connected to the first socket by an internal contact ring. A connector plug is inserted in the second socket to accommodate a plug-in l·amp, which replaces the illumination mirror. When the current is on, this lamp illuminates both circles, both the horizontal and vertical level vials, and the telescope reticle. A rheostat is provided on the battery case for adjusting the intensity of the light. A hand lamp is attached to a second cord from the battery case and is used to provide general illumination around the instrument. (2) Diagonal eyepieces and sun filter. Standard equipment includes diagonal eyepieces that screw directly into the telescope and the reading telescope eyepieces. A sun filter is provided for the telescope eyepiece. (3) Compa.ss. A circular compass is issued as an accessory item for the T16 theodolite. When the circular compass is used, it is mounted in the compass bracket located on the standard opposite the vertical circle. The compass is used only to provide a rough check on an azimuth, to orient the sketch in the field notes, or to obtain a direction for assumed control. The compass should always be pl•aced in the pocket of the accessory case with the dial down to prevent breaking the cover glass. f. Tripod. The universal tripod is issued with the theodolite. This tripod has extension legs and accessory case. The accessory case is made of leather and is mounted on the tripod AGO 10005A with wood screws. The case contains a plumb a. Place the telescope in a vertical position bob with a plug-in sleeve and a wrench for with th~ objective lens down and tighten the the tripod legs. vertical clamping screw. 159. SeHing Up the Theodolite b. Turn each leveling screw to the sameheight. a. Setting Up the Tripod. The tripod usedwith the T16 theodolite is similar to that used c. Position the horizontal clamping screw di with the aiming circle M2, and the same prorectly· over one of the leveling screws and cedure is used for setting up the tripod (para tighten it. 148a). d. Grasp the instrument by its right stand b. Removing the Theodolite from its Case. ard and unscrew the instrument-fixing screw.To remove the theodolite from its case--Lift the theodolite from the tripod and secure (1) Grasp the carrying strap with both it in the carrying case. Replace the dome-shapedhands just above the two clamping cover. levers and pull outward to release theclamping levers from the base asseme. Replace the tripod head cover, collapse the bly. tripod, and strap the tripod legs together. (2) Lift the dome-shaped cover directlyoff the instrument and lay it to one 161. Reading and Setting Horizontal and Vertical Circles side. (3) Pull upward on the two base clamping a. With the T16 theodolite prepared for oblevers that secure the theodolite to the serving as described in paragraph 159, open the illumination mirror and adjust the light so thatbase assembly. Grasp the theodolite by the standard that has the tradeboth the horizontal and vertical circles are unimark inscribed on it and lift the theformly illuminated when viewed through theodolite off the base. circle-reading microscope. Adjust the focus ofthe microscope until the image of the circles (4) Attach the instrument to the tripod head by screwing the fixing screw appears sharp and distinct. snugly into the base of the tribrach. b. When the circles are viewed through the (5) Replace the cover on the base of the circle-reading microscope (fig. 35), the vertical case to prevent dust and moisture circle (marked "V") appears above the horifrom entering the case. zontal circle (marked "Az"). Both circles are c. Plumbing and Leveling the Theodolite. The graduated from 0 to 6,400 mils with a majorprocedure for plumbing and leveling the T16 graduation each 10 mils. Unit mils and tenthstheodolite is the same as that for the M2 aiming are viewed on an auxiliary scale graduated in0.2-mil increments from 0 to ·10 mils. Circle circle (para 148c). After the instrument is leveled, check the optical plumb to insure that readings are estimated to the nearest 0.1 mil. the instrument is centered exactly over the staThe scale reading is taken at the point where tion. If it is not, center the instrument over the the major (10-mil) graduation (gageline) is station by shifting it on the tripod head, and super-imposed on the auxiliary scale. When the again check the level of the instrument. If nectelescope is not in a horizontal position, the essary, repeat the leveling process and again scales will appear to be tilted, with the amount check the optical plumb. Repeat this process of tilt depending on the inclination of the tele until the instrument is level and centered over scope. the station. c. All horizontal angle measurements withthe T16 theodolite should be started with an in 160. Taking Down the Theodolite itial reading of 1.0 mil on the horizontal circle. When observations are completed at a sta For practical purposes, this reading precludestion, the theodolit-e and tripod are march working with a mean of the direct and reverseordered as follows: (D&R) pointings on a starting station of less AGO 10005A 85 knurled ring on the telescope eyepiece until the reticle crosslines are sharp, distinct lines. (In doing this, the observer should be very careful • to focus his eye on the crosslines, not the sky.) • Next, point the telescope toward a well-defined distant point and, still focusing the eye on the crosslines, bring the point into a clear, sharp image by rotating the knurled focusing ring on the telescope. Use the horizontal tangent screw to center the vertical crossline on the point. To check for elimination of parallax, move the eye horizontally back and forth across the eyepiece. If the parallax has been eliminated, the crossline will remain fixed on the object as the eye is moved. If all parallax has not been eliminated, the crossline will appear to move back and forth across the object. To eliminate any remaining parallax, change the focus of the eyepiece slightly to bring the crosslines into sharper focus, and refocus the telescope accordingly until there is no apparent motion. Each time an angle is to be measured, the telescope should be focused to eliminate parallax, since accurate pointings with the instrument are not possible if parallax exists. Figure .3 5. Scale images view ed through the circle r eading microscope. 163. Measuring Horizontal Angles a. In artillery survey, the T16 theodolite is than 0 mil. To set this value on the horizontal used as a direction-type instrument, and the circle release the horizontal clamping screw horizontal circle clamp is used only to set the and rotate the instrument until the major initial circle setting on the horizontal circlegraduation 0 appe::~.rs on the horizontal circle. prior to making a pointing on the initial station.Clamp the horizontal clamping screw and use The method of measuring horizontal angles conthe horizontal tangent screw to set the 0 gagesists of determining, at the occupied station, line directly over the 1.0-mil graduation 011 the the horizontal circle readings to each observed auxiliary scale. Firmly engage the horizontal station, beginning with an initial (rear) sta circle clamp by folding it downward. The horition. The angle between two observed stations zontal circle is now attached to the alidade of is the difference between the mean horizontalthe instrument, and the reading of 1.0 mil will circle readings determined for each of the obremain on the horizontal circle regardless of served stations. The mean horizontal circle the direction in which the instrument is readings used to determine the angles are depointed. termined from two pointings (circle readings) on each observed station (fig. 36). 162. Focusing the Telescope To Eliminate Parallax b. With the telescope in the direct (D) position, the initial circle setting of 1.0 mil on the Before a theodolite is used for measuring angles, the telescope must be focused to elimhorizontal circle, and the horizontal circle clamp down, a pointing is made on the initial inate parallax by bringing the focus of the eye pie:!e and the focus of the objective Je·1s to the station. This establishes the direction of the staton at 1.0 mil with respect to the horizontal plane of the reticle {crosslines). This is accom circle. The value of the direct reading on sta plished as follows: Point the telescope toward the. sky or a neutral background a:1d rotate the tion A is recorded in the field notes (fig. 36). AGO 10005A 86 A AONITIAL,OR REAR,STATION) B ~ \ (FORWARD 7sfATION} \ /\ / / ~3429.4m ,o 229.3\m ' \ J \..-./ INSTRUMENT N~lfIZ.t~ltl-r-"1 L VEifTIC/It. VEif.TIGIIL. STATUJN T 2J. IllI L. S MEAN HE~DJNG ~ A /) OOD /. 0 R .3 2 "I. () ooo/.0 /NST Mil O:tt. ¥-1 C+1-n s 0 :1:1'1. 3 /St:, 3 2./JIJ. ~(),() IJti(J(). 183 R INST MW l'.t~r : s,+ Jeuu.s "'1-.e-e: f'{G. & .. .,,~ DE SIGNATIOtl ~l....'f.41f:! r e"-5 1.4rve.d!J. DATE u 19 :J; 5-' ill/ · M.z"~ t7F9 p~c. K.......... rc. " ·'"'".... ' · Gc.., Lr : e. ,.., Nn·/,_.,,...., .. / 1/e,.·h·c-../ c.,,.....,+,#~.. J),$+,_,.,c.. s.J~+ ~""' J? 4 ,.;/s 4 '".,,.. 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I $.cil••/ ,a, St:.l' Jh,. 4 114¥35.3' 1(--T.O) IG.fl) "-s~s p • l'fM I -rs-:L I J59 17 JI/J. 19 /.P !:i"''" ' · DESIGNATION f>tJH//IJH /IRER .SP.<'PEY DATE v~,-1,4£1 ~/$f...... , e. )htf'll""t•l ller-1,-c•l f?£MIIR. I/C~ MCT£RS RE MARKS STA· "ION DI'HIGf IS L ICATED N NOWTII AR81JCI(l t: AflFA T SILL 11 IILITA~Y rESfR.VATIO (fp.,~ .10) lo.Y MILE lA/. oF 8 IIILD fliDI lf R A Hr. f CENTRA tJI>J J.l ICillfi:T Po it.tT OF GIRASSY t,71. . 12. IJ/ILL. sfATION I 'I ME..Te l'.sw(j_N .sflo. s 1.12... ot METE.~ tJ IJt: q_ t:-Wlln MAFfJ(!:n BY 'flf'f IN ICOMl"UTI FLUSU WITH GRtJIIIND Ali[ 151 IAIIIITE IWIIIInC., b11an MA tKfR A;;~ Mk 1~ ~URO IMARKER ION Kill\"1A Ufll :zoaM s II /JF(sn. ,,_......., STATIIIN lnooc.JO aTS·~ S3 7.1/1/ 1/ 537.'17 I ~T -1 ./ ' ,.,. ~ _.{t¥,., - ;:..-..L-· - - I / / ~ l{tiiWA "' ro fourth-order (T2 theodolite) traverse. signal the rodman to raise or lower the bottom light on a range pole or inform the rodman to move to the next station, etc. In arranging signals, the survey party should avoid waving the lights, since a waving light may easily attract the enemy's attention. Every precaution should be taken in sending light signals to avoid detection by the enemy. 202. Traverse Field Notes For examples of field notes on traverse, see figures 47 through 49. Section II. COMPUTATIONS 203. Azimuth Computation In order for a traverse to be computed, an azimuth must be determined for each leg of the traverse. The azimuth is determined for AGO 10005A each succeeding leg of the traverse by adding the value of the measured angle at the occupied station to the azimuth from the occupied station to the rear station. The example which follows illustrates this procedure. It should be noted that on occupation of each successive station the first step is to compute the back North azimuth of the preceding traverse leg; i.e., the azimuth from the occupied station to the rear station. Azimuth of line A B = a. Example Problem. /2400.0 mH• (1) Given: Azimuth from station A to az mk 5592.6 mils Angle az mk-A-TS1 2134.0 mils Angle A-TS1-TS2 3820.5 mils Angle TS1-TS2-B 1756.5 mils (2) Required: Azimuth from station TS2 to B. b. Solution. B (1) At station A- South Azimuth from A to azmk = 5592.6 mils F i gu re 50. R elationship of azimuth and bearing. ( + )angle az mk A-TS1 = 2134.0 mils azimuth of a line is defined as the horizontalSum = 7726.6 mils clockwise angle from a base direction to the( -) a full circle = 6400.0 mils line. The base direction used in artillery surAzimuth A to TS1 = 1326.6 mils vey is grid north. The bearing angle of a line (2) At station TS1-is the acute angle formed by the intersection Azimuth :from station of that line with a grid north-south line. FigA to TSl = 1326.6 mils ure 50 illustrates the relationship between the ( + ) a half circle = 3200,0 mils azimuth of a line and its bearing. Azimuth from TSI to. A = 4526.& mils b. The manner in which bearing angles. are(+)angle A-TS1-TS2 = 3820.5 mils computed from a given azimuth depends on theSum = 8347.1 mils quadrant in which that azimuth lies (fig. 51). ( -) a full circle = 6400.0 mils When the azimuth is in the first quadrant, 0 to Azimuth TS1 to TS2 = 1947.1 mils 1,600 mils, the bearing is equal to the azimuth. When the azimuth is in the second quadrant, (3) At station TS21,600 to 3,200 mils, the bearing is equal toAzimuth from TS1 to TS2 = 1947.1 mils 3,200 mils minus the azimuth. When the azi( + ) a half circle = 3200.0 mils muth is in the third quadrant, 3,200 to 4,800 mils, the bearing is equal to the azimuth minus Azimuth from TS2 = 5147.1 mils 3,200 mils. When the azimuth is in the fourth to TS1 (+)angle TS1-TS2-B = 1756.5 mils quadrant, 4,800 to 6,400 mils, the bearing is equal to 6,400 mils minus the azimuth. Sum = 6903.6 mils (-) a full circle = 6400.0 mils 205. Coordinate Computations Azimuth TS2 to B = 503.6 mils a. If the coordinates of a point are known 204. Azimuth-Bearing Angle Relationship and the azimuth and distance from that point to a second point are known, the coordinates a. An azimuth is required in traverse to perof the second point can be determined. In figmit the determination of a bearing angle. The bearing angle of a traverse leg, not the aziure 52, the coordinates of station A are known I muth, is the element used in computations. The and the coordinates of TS1 are to be deter- AGO 10005A 114 4 ' northing (dN) to the northing coordinates of North station A. Bearino = 6400 mil s-ozimuth BearinQ = oz imuth b. In figure 52, the traverse leg appears inthe first quadrant. It is for this reason that I dE and dN must be added to the easting andnorthing coordinates of station A. If the traverse leg were to appear in one of the other West ------1--------- Eost quadrants, the signs of dE and dN wouldchange The signs of dE and dN are determined by the quadrant in which the traversem n leg lies (fig. 53). Bearin o = az imuth-3200 mil s Beor ino = 3200 mils -az imuth 206. Determination of dE and dN South The determination of the values of dE anddN between two points when the azimuth and Figure 51. Determination of bearing angle. distance between those points are known requires the solution of a right triangle. In figuremined. The azimuth and distance from station 52, side A-TS1 is known because the distanceA to TS1 ha ve been determined by measuring between A and TS1 is a taped distance. Thethe horizontal angle az mk-A-TS1 and by tapbearing angle at station A is also known, sinceing the distance from station A to TS.l. The it was readily determined from the azimuth ofgrid easting and grid northing lines through station A to TSl. Since the intersection of theboth of the points are shown. The coordinates north-south line through station A and the eastof TS1, are determined by applying the difwest line through TS1 forms, a right angleference in easting (dE) to the easting co(1,600 mils), a right triangle is created withordinates of station A and the difference in the hypotenuse (side A-TS1) known. j To dete1vmin:e dE: opposite side dE Sine of bearing angle = hypotenuse distance or, dE = sine of bearing angle X distance. To determine dN: adjacent side dN Cosine of bearing angle = hypotenuse distance or, dN = cosine of bearing angle X distance. 207. Scale Factor of the occupied station from the centralmeridian of the UTM grid zone. The scale fac The log of the scale factor is applied to the tors are given for every 10,000 meters east and dE and dN computations of all surveys executed to fourth-order accuracy. The purpose west of the central meridian and a:re shown intabulated form on the back of DA Form 6--2 of the log scale factor is to convert ground dis tance to map distance when the UTM grid is (fig. 56). The values of the scale factor are ex used. This factor is not used in surveys pertracted by entering the table with the approxi formed to accuracies of less than fourth-order. mate easting value of the occupied station to The scale factor value varies with the dis.tance the nearest 10,000 meters. AGO 10005A 115 Az mk B Figure 52. Requirements for dE and dN. 208. Determination of dH dE-dEt TS1 TS1 In a traverse, the height of each traverse station must be determined. This is accomplished dN+ by determining the difference in height (dH) between the occupied and the forward station. The vertical angle at the occupied station andnr I the horizontal distance from the occupied station to the forward station are us.ed to deter m li. 4 mine the difference in height between the two by solution of a right triangle. In figure 54, dN the distance is the horizontal taped distance from station A to TSl. The vertical angle at TS1 TS1 station A is the vertical angle measured to HI dE-dE+ at station TSl. The difference in height between the two stations is the side of the right triangle which requires solving. Figure 58. Relationship of quadrant and sig1•. To determine dH: opposite side dH Tangent of vertical angle = adjacent side distance or, dH =tangent of vertical angle X distance. 209. DA Form 6-2 210. Determination of Azimuth and Distance From Coordinates a. DA Form 6-2 (figs. 55, 56, and 57) is used a. In survey operations, it is often necessary to determine coordinates and height from azi to determine the azimuth and distance between muth, distance, and vertical angle. two stations of known coordinates. Some ex b. Entries on the form are shown in figamples of such a requirement are computation ures 55 and 57. of a starting azimuth when the coordinates of c. Formulas to be used are shown on the back two intervisible points are known, computation of DA Form 6-2 (fig. 56). of azimuth and length of a target area base AGO lOOOSA 116 TS.l(Forword sta) dH Figure 54. Right triangle for determination of dH. or the base of a triangulation scheme, and com ence between the two easting and northing coputation of azimuth and distance between critiordinates. The signs ( +) of dE and dN, ascal surveyed points when swinging and sliding determined on the form, are used for findingthe grid is necessary. The standard form for the quadrant in which the azimuth is located.this computation is DA Form 6-1. Figure 58 As in paragraph 208, the right triangle formedillustrates. the computation of azimuth and dis by dE, dN, and the grid distance is used totance from the coordinates of two points. dE determine the bearing angle of the desired azi and dN are determined by finding the differ-muth as follows: opposite side dE Tangent of bearing angle = ---- adjacent side dN Logarithms are used to solve for the bearing b. The bearing angle and dE or dN, whichangle on the form. Once the bearing angle is ever is larger, are the factors needed to comknown, the azimuth can be Teadily determined pute the distance between the two points.from the block in the upper right corner inwhich dE and dN were plotted. opposite side dE Sine of bearing = ----hypotenuse grid distance adjacent side dN Cosine of bearing = = hypotenuse grid distanceor, dE dN Grid distance = or----- sin of bearing cos of bearing Logarithms are also used to solve for the grid lines of sight must be considered for traversedistance. The larger side is used, since it is legs in excess of 1,000 meters. These effectsopposite the stronger angle in the right tri ca be compensated for by reciprocal measureangle (para 228), thus enabling the determinaments of the vertical angle at each end of suchtion of a more accurate distance. a leg. When vertical angles are measured reciprocally, the vertical anghe at each end of the 21 1. Reciprocal Measurement of leg should be measured to the same height Vertical Angles abO'Ve the station (normally HI). If this cannotThe effects of curvature and refraction on be done, DA Form 6-2b, Computation-Trig- AGO 10005A 117 CD - ~ ~,....,,...,,...,,.. COMPUTATION • COORDINATES AND HEIGHT FROM AZIMUTH, DISTANCE AND VERTICAL ANGLE ( FM 6-120) .U:Mint •nat TO f'Oin'Attl nATO! '\:: :\: :::-. , l 2Jc.st ~T'U MIKOtiT ~ li!AUT.U!Otl ~!:::..u• ~2 j lf7l .5 . ' _I ' I ' ,,, I t + ....-.. I 03' I tJ :f:::! ........... ••oo·· ·-'".. ....... .::. 55~ 187. t:. .3 835 9.ZB. ~ /32 . 7 ~ -k· ,. 1-'~ 50S '"'~"' 9l 464 0 1 5 6 "'~"" 9 ~ 464 0 156 w 18 I~ ,. (£) 1 27~ 7 . (f) 110 . 2 ~GJ ,2 ~ () '-(.t, 501() .2 1 1 1 , ,-..:: , 4 1 0 () 0 ...... ·::,~.:;· 1 ••KM 1 " ""' 1 1 1 1 1 9e~t ~ 73:< ..~:·.:.::.a~ ..zlf91 7.2.5 I I ~ : I I : ~ t<:l.::. .J:~oo1 o:: :~ II.J . t.; ,;·...~ 21 ossi#I7 "~~" 2Tos5T J.J./'7 =~" 2 o.5~J/.11 : : 1 I i ~ 1 ""''' 2 1.So 1 5 2 •.~? s ~:::;, 913Bt. f':tt ~::.~:: 9 1 ·-~ / "1JfiB.J8 2! o¥2'1~9 ·-..: oT.JoSTI"'-2 1 ...,_ .J-!:5t'1 5 1 1 1 10 18 r .5'I '.55~2t5~ 3 ·:J 6'3&. 1oJ8. 6 · 1;.J~. 7 • .21. ·f-·• .......... I""""' , I .,.{+) I 4H+ •":::: I T ~~({In I ~ +-I ., 1 ~ .. 0 -0 U HICOBS .....~ a :s8o172t, ~"-· 8. ..._ •~ ,I I , ~ I I I I I I I I .I onua , •• , I I •~ ,I . (+).., .2 . 070 /..Z'! ....c. 2.0'!0 (.2.'/ ""'"" 2 .P10 I(..Zy --· .J.Z I 00 () :: :: ' 117.(.1.., M·-· I I I I I I -· I -· ' -· I I I 1 i ........ I I ~· .Z . tJ70 ,JIJf ·~-o:t,SI 3.5"5 .... o .28.Z 771, ""-~61 JB 8 1 •f.•+ (. '3 83(. /0/ ~ t, • /32 .8.:.._ 1 +".',';:; t : I ... •+ """-~ '"''""' /..f.J SS~ .309 ~ + ~ + 1 ~ 1 ••~• 9 l 4 6 4 0 I 5 6 ,;::::;-;., 9 ~ 4 6 4 10 I 5 6 ·::~" • + : I ~ " + 1 I -~'!.~' I I ·::,-::· .I : · ~·-I I I I I I I I ~ -..:: : I .._ I ...... T I I I I I I ~I '""' 1 T " " " I vu t ..OIIOU I UUIOI C ....'" n •• ""'-I I I (.,... I I ...... ' ... I I ·~ I I '" I I I II II II II II II II <:t:: : + ' " ..._, ""'""--· I ..•.. ••• I I ·~-I : ••• T ; 1 ':,;",.:" 1 . I I I I I . ·-'""'-·~•M• I"""* I j'! ... :":"""::·"""-I •· •• •u• " •••MIIco • .v.""' rnTtDootTtn [ Ct4!CUI .._._,. •.U: •+ •. tn " " [ ctlloii'\ITU I . • t .._,.... PUTfOUlOS .. ,, "•1 1 I o r SII UU iE .._~.. ..a · ;!., : : =~ ul~fl -.u: =~~::::!:;, 1 SII UT E DITION OF 1 OCT t12 IS OBSOLETE. D.A .~~~M.. 6-2 Figure 55. Sample computation of fifth-order traverse. --·----------~ L _______..__________________ ~ I • ., 8... > <> <> >"' TABLE-UTM GRID SCALE FACTORS FOR ARTILLERY Add log scale facror to log ground distance tO obtain log UTM grid ~ist~nce. GIVEN: The easting value used to determine log UTM scale factor is easting of the Coordinates and Height of occupied station. known station to nearest 10,000 meters. Azimuth STATION to REAR STATION.EASTlNG OF STARTING STATION LOG SCALE FACTOR FIELD DATA: 500,000 500,000 9.9998300 Observe horizontal angle> and vertical angles.490,000 510,000 9. 9998300 Tape horizontal ground distance between occupied station and for ward station.480,000 520 ,000 9.9998300 GUIDE: 470,000 530 ,000 9.9998aoo Enter fi e ld data in blocks marked. E=:] \460,000 540 ,000 9.9998300 Sign of dH; (+)when e levation angle, (-)when depression angle.550,000 ~/,e>.f LIMITATIONS: ~ St!a-le rat:cor 440,000 560 ,000 9,9998400 This form should not be used fo r vertical control when horizontal distance 430,000 570 ,000 9.9998600 exceeds 1,000 meters unless reciprocal vertical angles are observed and 420,000 580 ,000 9,9998600 meaned. 410 ,000 590,000 9,9998700 This computation requires that HI at occupied station and height of target 400,000 600,000 9,9998800 at forward station be equal. 390 ,000 610,000 9,9998900 When distance exceeds 1 ,000 meters or when HI and height of target are 380,000 620,000 9,9999000 unequal use DA Form 6-21i for more accurate vertical control. 370 ,000 630,000 9.9999200 RESULTS: 360 ,000 640,000 9,9999300 Coordinates and height of forward station. 350,000 650,000 9.9999500 FORMULA: 340,000 660,000 9,9999700 dE =dist, x Sin Bea ring dN =dist. x Cos Bearing dH =dist. x tan vertical angle. 330,000 670 ,000 9.9999800 320,000 680,000 0,0000000 310,000 690,000 0.0000200 300,000 700 ,000 0,0000400 290 ,000 710,000 0.0000600 280,000 720 ,000 0,0000900 270,000 730 ,000 0,0001100 260 ,000 740,000 0,0001300 250,000 . 750 ,000 0,0001600 240 ,000 760,000 0,0001900 230,000 770 ,000 0.0002200 220,000 780,000 0,0002500 210,000 790 ,000 0.0002800 200,000 800,000 0,0003100 190,000 810 ,000 0,0003400 180,000 820,000 0,0003700 170,000 830,000 0.0004100 160,000 840,000 0,0004500 150,000 850,000 0.0004800 140;000 860,000 0,0005200 130,000 870,000 0.0005600 120,000 880 ,000 0,0006000 11 0 ,000 890 ,000 0,0006400 100,000 900,000 0,0006900 t:t U. $, GOVERNMENT l'fiiNTING OfflC£ : 1955 o-35562:9 - F igure 56. Back of DA Form 6-2. -o ---1 ~ -0 I I I I I I I I I I I I > Cl 0 0.... 0 "'0 > ~ I •.,_,_,._ COMPUTATION • COORDINATES AND HEIGHT FROM AZIMUTH, DISTANCE AND VERTICAL ANGLE (FM 6-2 and FM 6-122) •n01 TO...,.-.,..,... .u:...,lM ,_.,.. ....., , :::.:.::" 4'1l!-f1o71.1 >; · ir ~ IIi t;.··•; · . " " ""' JO£ 5SO 1 ~~~~. 13 3 1f371f.:J.3.3S '/-/8 :3 + M&< F 38 ' SJI~OfJ : : :! -Kt 0.2.115J f 32 ()O fJOO .:::::-::. -~ .·::::-::.. Q ·:::::~ ~ I N 1~7~ HG> I 57(#1~ 55-~ I 578~ ,., ·e 11 18 W' . , 1 1 lA_ :ll/-()~ IS. M<~ I t20/ '"'" I I I uno., 1 07 05 by."""' '1 :tso l I I 1 I I 1 I 2 I I -·--3.z. 1oo"""o:: :: 811.39';=.1 ··..~· 2. ' 912.11{-21"' """" 2. : '112. 1"1293 ··"'" 2. : '112.1.1-293 I . I •.,,.... /~ -· , I ~I r<1 -· 1 ~ ., 1 'fl -· 1 1I I 1I I / ·~ · .2 . 7~bl3'-'t '"• 2 : 1w ... 11{. '"• I.0108f'IJ 1 ""-Sit. 0~ :::./ 1 1•+ u.:.._ .,,,_ T5-l 'S5J 1 o:Jlj. ~ t.8 " 3 1 8J71 o'ft/3t, " '1-tJ~: s +":::: .3b 14 q,~ •-·····. -q 2. .::-:.~-::. .! ·::.~:-~ I ' : ift~ .GJ :2si '., -e I 8 '~'~ . o., -e . ' .~ I ·:-::::-:.. . 2~ 81 1/ll!> ·•~• I 1 1 ·~·~· I •••~· I I I I I 87 Iif? -f-· 32 oo ooo -I ~. '1"19 tt~oo ""~ q .'l'f911'/oo ...... . ---"~ 1oo {lao .....c ···~ I I I"" I 3 I " t1 , '"•• I I """ I ,., I ·~... I 'I 2t./ / 1 01/01 15' •0 -1'1 17 31 '{fl/ ...... I ' I ....... I ' I ,...~ I I I ... ,, I I. · ~·• -l_c...---;-- -_, "7 L0 0 000 •.•-• ""~ ''f9 '1"/ 18 ~~ 00 •••• 'f . "/'/'/ f 'f0() 'I s·; ,.... I ..... I ••••• ' I . , I I I I I II ,j u,._ 9758"·"~ 9. 131 1 1S'II ""-· s. o~.,.~~~3s I I I I I ..._ 11 38'1~'-1 ''Y'.....":. ~ ....., 1. "1951 1 (:).::;.. .32 ;ooooo : : 1 1 1 :.: 1,0so..u~ ...::. 3 o.t.l ~1fo3 ··:~· .3 !o:l./ 1 2143 ·:'=:· 3~ 0~I ; A8b3 I I I I I I 1 • .,,_ .i,i1 :31':•U'/. ,' ~· :io1711J'/'-I •"• 2. ~ /53 ()15/ ··-l !oi./71S.:l.31f 1 '.s5J. 1.350 1 tJI ·3 1 1f.Jit.1 oo31 o; · 1 Jl.tlt. .J ,:_ • ": t Jl./ 1ss~n • . •• .. .. .._ r """"' 8/11 sc P 1 1 "' ::::::-:.. " ~ ·:::t ~ 2 10 1~ ..Q : S'/-/ 1Jl.l. -&> 1 "1'1'1 . :J.1 -6J .:J ~ 3 -q 0 "''l:zl9 •t·• 3 .2.. oo ooo ..·::::::. I 1 1 1 1 ~'I-: ooiooo .u'...'!f 1.1-1 ~'!.":'1 ! 'f '11 1ft!oo ·-:::::~· q 19'1'1 111/00 ·~:.~·:: . I I 1 Loc(Ot r Lo'u" 1 r -.:. S . ..-1 77 L...... 1 .r 1 I I I I u .. _ ""-21, 19'/-t.i-? 0 "' ' ""-'1 . ~77' '/Sio ....... '1 .'11/l/ IO.S'f '""~" 7 : 3o7'91b8 I I •• 1 .1 , ,. , 1 -' I I I I (.,.... 1 1 •.,_, • ... 1 5. 1 ~ I _,_, 32 oo·ooo:: : : / , 131:..'1'1~-·-· 3:os 737.., •.,_, 3 : o5S 737 •.,_, 3 . 055737/, 1 -:.:-..::" S'i 1 '1'i1 ~i: .::: .z ! 7331 S.Js~t. ..::: 2 1 9'1'1 ;{.835 .:.":.' o !3"31 70S'f 1 I I I I I 1 1 ·-·:, -u ~T"~T"·~-....::·~..:~ ~ ~::::~·:::: ,~..."-·~··· : ::;:;:: =u TS-3 '"""' '.s.s2.. 1 ¥91.'1.3 .3 33SooJ'7Jf ' l ,t/l ! b~~ i: •-I._ ,_, -.,.,,,.,.,., J(EUTNAN I BLb_X,_. Y05 /' .i ·.·) \ f'OIU•ULAJ• =~ '''''L22 T AN BEARING:.!!. GRID DISTANCE : ~ = ~ '" COMPUTER ICHECKER I SHEET OF SHEETS NOTU:>QK .U(AREFERENCE DATE fORMDA I AUG SS 6-1 REP L ACES EDITION OF I NOV 53, WHICH WILL BE USED UNTIL EXHAUSTED. Figure 58. Computation of azimuth and distance, fifth-order survey. AGO 10005A 121 COMPUTATION-TRIGONOMETERIC HEIGHTS , OCCUPIED STATION .sc. F 2 sc P 3 FORWARD ST ATIOH scP3 sc.Pl.f I I I I I I HEIGHT OF INSTRUMENT + -:1 ATOCCUPIEDSTATIOH + : / I " t + : /I " + I I I HEIGHT OF TARGET I I &:, t-I I I &:, - AT FORWARD STATION I I ~ I 0 I 0 = I () I 0 = I ALGEBRAIC SUM (1) AND (2) ! I I HEIGHT OF INSTRUMENT -I I I b t-I AT FORWARD STATION t-I I I b I I =~ s ALGEBRAIC SUM (3) AND (4) ~ 1 / I "~ lib~ 1 I I I HEIGHT OF TARGET AT OCCUPIED S moNt+ 1 1 1 " + ~ /I&:. + ; + 1 ~ O-+~---~~~O~I~O~~~---~~--;~ --~~--~~----,I--4 ~~~AL_G_E_BR_A_Ic_s_u_M_(S_l_AH_D_(_6l________-+!___+-I~O~~ ~ 112 OF m :!: 0 I 0 :: 0 I 0 ~ . ~ I :!: I I I---~-+--~~~ ~,~-r--~~l-;1---r~+--~.-~1 --~ ~~~VE_R_T-IC_A_L-AH_G_L_E_O-CC_U_P-IE_D_S-TA-T-10-H---+~--_.~~ I 1 1 ,_ I I :.c 9 TOFORWARDSTATIOH F l/fi7V~ 11013dt 1 I I I I I I ~+ I I ~ VI::RTICAL ANGLE FORWARD STATION TO ~ ~ 10 OCCUPIED STATION WITH SIGH REVERSED 1 /11131f::5;J I //) 1 3~l 1 I 1-1 j 1 I ~ 11 ALGEBRAICSUM(9)AHD(10) ~ :31 , J'3~ :/{) : l,lj.~ I I ! I ~ /fl 12~ /IJ 32.:!: :!: I "'12 1/ 20F(11) I 14 LOG TAN (12) I I I IS (13J+(U) I IF HORIZONTAL DISTANCE IS: GRID, I I I USE LOG SCALE FACTOR FROM I I [16 REVERSE; GROUND, LEAVE BLANK I I I I ~ I I ~ I I I + I I NOH. RECIPROCAL ANGLES ONLY: I I + I I II I I I CURVATURE AND REFRACTION + + + [21 CORRECTION FROM REVERSE I . I . 1 I I I + I II22 ALGEBRAIC SUM (20) AND (21) ~ : I", 1 " <> : 3'1: 7 ~ + l I I I I I + I I . I I .I I COMPUTER 8 D .tl I) A I 'CHECKER flo F£i.OT SHEET OF SHE ETS ",.., IV NOTEBOOK IAREA DATE /M JIIN REFERENCE I-I~ FOXTROT DA FORM 6-2b, 1 OCT 52 , WHICH I S OBSOLETE . DA FORM 6 2b REPLA CES 1 MAY 56 Figu1·e 59. Computation of height, fourth-order survey. AGO 10005A 122 TABLE· CORRECTION FOR CURVATURE ANOREFRACTION TA8LE·UTM GRID SCALE FACTORS FOR ARTILLERY (No interpolation necessary for Artillery Survey)Use ~when dH is computed using non-reciprocal venical angles, EASTING OF STARTING STATION LOG SC ALE FACTORSIGN ALWAYS PLUS 500, 000 500,000 9, 9998300 Enter in (21) 490,000 510,000 9. 9998300Log Oist (M) Corr (M) 480,000 520,000 9, 9998300 410, 000 5~0. 000 9. 9998300460, 000 54 0 , 000 9. 9998300 3,019 • 1 4~0. 000 550,000 9. 99984003,230 .2 440,000 560, 000 9. 99984003,322 .3 430, 000 570, 000 9. 9998500 420,000 580, 000 3 ,386 • 4 9. 9908600410, 000 590, 000 9. 9998100 3.435 .5 400, 000 600,000 9. 9.9988003,413 .fr 390,000 610,000 9. 99989003,508 . 1 380,000 620,000 9, 99990003,531 .8 310,000 630,000 9 . 9999200 360, 000 640,000 9, 9999300 3,562 • 9 350,000 650, 000 9 . 99995003,584 l.O 340,000 660, 000 9, 99991003,625 1,2 330,000 610,000 9 . 9999800 3,658 1.4 320, 000 680, 000 0. 00000003,681 1.6 310,000 690, 000 0. 0000200 3,112 1.8 300, 000 700, 000 o. 0000400 290,000 71 0,000 o. 0000600 3,136 2, 0 280, 000 720, 000 0. 00009003,184 2.5 210, 000 730, 000 0, 0001100 3,824 3. 0 2GO , 000 740,000 0, 00013003,857 3,5 250, 000 150,000 0, OOOIGOO 3,886 240,000 7GO , 000 0 . 0001900 4 . 0 230, 000 710,000 0. 00022003,912 4,5 220,000 180,000 0, 00025003,934 5.0 2 10,000 790, 000 0, 00028003,955 200.000 8 00. 000 5.5 0, 00031003,914 6,0 190, 000 BIO, 000 0. 0003400 3,992 6.5 180, 000 820,000 0, 0003100 110, 000 830, 000 o. 00041 00 4 . 001 1. 0 160,000 840, 000 o. 0004500150, 000 850, 000 0, 0004800140,000 860, 000 o. 0005200130,000 870.000 0., 0005600120,000 880, 000 0, 0006000110,000 890, 000 o. 0006400100,000 900, 000 0, 0006900 Given: UTI\t grid distance or lt orizomal grtHIItd distance in meters between stations. lkigltt of oue station in meters. field data: Observe vertical auglc hct...,'eell instrumetll at one station and target at other station, !Ieight of ittstrument. !Ieight of targl·t. (.;uic.Je : Enter field data in blocks trrarkec.J LJ______,f. When vertical anglc·s arc observed in l"-' <> dircctiuns, dthcr stauun may be designated a s the occupied station, Use Blocks I, II, and IV. When vertical angle is observed in one directio n, usc l:llocks I, Ill, and IV. Use curvature and refraction correction from table above. Elevation of occupic.!d station need not he known. b1 (Jfi), obtain appmxitnate casting co0rc.Jinatc of occupicc.J station from other computations or from map. Use this valul' to obtain scak factllr front tahle abnve. If height of C' itlter stat inn in(~:!) is hdow sea level(-), ac.Jc.J 1,000 meters algebraically to (23); proceed with computation as· inc.Jicatl'U, Subtrac t 1,000 meters alg..:braically fr< >tn (~~) to obtain height of station.If height of occupkc.J station is used in ( ~:!), then ltdght of forward stati0n is obtained in (2.5). All atigular units ·usec.J in computation must he the sa me (mils or degrees). Limita.tion: This ~omputation Ut provide for reduction of ground distance to sea level distance. Resu lts : lldghi: of the· unknown station in meters. . GOVERNMENT PRINTING OFFICE : 1956 0-385533 Figm·e 60. Back of DA Form 6-2b. AGO 10005A 123 the angles. Horizontal angles are measured oneonometric Heights (fig. 59), must be used in computing the height of the forward s.tation. position; vertical angles are measured once with the telescope in the direct position and once with the telescope in the reverse position 212. DA Form 6-2b (1D/ R). Distances are double-taped to a com a. DA Form 6-2b (figs. 59 and 60) is used parative accuracy of 1:5,000 with the 30-meter to determine the height of the forward station steel tape or measured with electronic distancewhen the vertical angles are measured recipromeasuring equipment, using the procedures discally or nonreciprocally to different heights cussed in chapter 6. above the station. (1) Posit·ion accuracy. b. Entries required are the vertical angles (a) The maximum allowable error in measured, height of station, height of instruposition closure for a fourth-order ment, and height of target. traverse is generally expressed as c. The formula to be used is shown on the 1:3,000, or 1 meter of radial error for each 3,000 meters of traverse. back of the form. The radial error of closure is the linear distance between the correct 213. Accuracies, Specifications coordinates of the closing station and Techniques and the coordinates of that station The overall accuracy of a traverse depends as determined from the traverse. on the equipment and methods used in the The radial error of closure is determeasurements, the accuracy achieved, and the mined by comparing the correct coaccuracy of the starting and closing data. In ordinates of the closing point with artillery survey, three minimum accuracies the traverse coordinates of thatserve as standards for survey personnel to meet point. The difference between the in both fieldwork and computations. These actwo is the radial error of closure.curacies are fourth-order (1:3,000), fifth-order (1:1,000), and 1:500 survey. Fourth-order surCorrect veys are normally performed by division artilcoordinates lery and the corps artillery target acquisition of closing point: 560068.0-3838037.0 battalion to extend survey control. Field artil lery battalions normally perform fifth-order Traversesurveys to establish survey control for the recoordinates quired elements of the battalion. Survey to an of closing accuracy of 1:500 normally is performed only point: 560064.0-3838040.0 by artillery elements that have a limited survey eE = 4.0 eN = 3.0capability (e.g. radar sections) and use the aiming circle to measure angles. The specificaThe difference between the two tions and techniques to achieve the accuracies eastings of the closing point, error required in artillery survey are tabulated in in easting (eE), forms one side of appendix II and are discussed in a through c the right triangle in figure 61; the difference between the two north below. ings, error in northing (eN), forms a. Fourth-01·der Accuracy. A fourth-order a second side. The hypotenuse of the traverse starting from existing survey control right triangle is the radial error of must start and close on stations established to closure. an accuracy of fourth-order or higher. If sur(b) The radial error may be determined vey control of the required accuracy is not available, the fieldwork and computations can by computation on DA Form 6-1, by using the Pythagorean theorem,be completed and the traverse evaluated for or by plotting eE and eN to scaleaccuracy by using assumed starting data, proand measuring the hypotenuse. Thevided the traverse is terminated at the starting most commonly used of these sysstation. The T2 theodolite is used to measure AGO 10005A 124 :rraverse coordinates plot here Radial error of closure eN= 3.0 eE=4.0 Figure 61. Radial error of closure. terns is the Pythagorean theorem. been determined, one other factor is By use of this theorem and the required to complete the computa data in figure 61, the radial error tion of the accuracy ratio. This would be computed as follows: factor is the total length of theRadial error V (eE)2 + (eN)2 traverse which is determined byadding the distances of all traverse v 4.02 + 3.02 legs (excluding distances to offsetv 16.0 + 9.0 stations) in the traverse. Assuming v 25.0 that for the radial error computed 5.0 meters above the total iength of the traverse is 5,555 meters, the accuracyWhen the radial error of closure has would be determined as follows: 1 Accuracy ratio = ----------------total length of traverse radial error1 5555 5.01 or, rounded down,11111 1100 (c) This accuracy ratio is suitable for reason, when the length of the trav evaluating a traverse in most cases; erse exceeds 9 kilometers, the allow however, when the traverse is long, able radial error (AE) in meters is the accuracy achieved may be computed by the formula AE =within tolerance and yet the radial y K, where K is the total length error will be excessive. For this of the traverse to the nearest one- AGO 10005A 125 tenth kilometer. For example, the in the direct position and once with the tele scope in the reverse position (1D/ R). Distances allowable error for a traverse 14.8 kilometers..---1!:!. length would be are single-taped with the 30-meter steel tape AE = y 14.8, or 3.85 meters., and checked for gross errors by pacing or are rather than 4.93 meters if computed measured with electronic distance-measuring equipment if it is available. by the 1:3,000 accuracy ratio. (2) Height accuracy. The allowable error (1) Position accuracy. The maximum allowable error in position closure for in meters for the height closure of a a fifth-order traverse is expressed by fourth-order traverse of any length is the accuracy ratio of 1:1,000 or 1 me also computed by the formula AE = y'"'K. By this formula, the allowable ter of radial error for each 1,000 meters of traverse. (See a(1) (a) height error for a traverse of less than above for determination of radial 9 kilometers will be slightly greater · error.) than the allowable position error, (2) Height accuracy. The maximum al whereas the allowable error for height lowable error in height closure for a and position will be the same for trav erses 9 kilometers or greater in fifth-order traverse is +2 meters. (3) Azimuth closure. The allowable error length. m azimuth closure for a fifth-order (3) Azimuth closure. The allowable error traverse is computed by the formula in azimuth closure for a fourth-order AE = 0.1r/t X N, where N is the num traverse depends on the number of ber of main-scheme angles in the main-scheme angles used in carrying traverse. the azimuth through the traverse. The allowable azimuth error in mils for a c. 1:500 Survey. The specifications and techtraverse that has no more than s.ix niques that apply to the fieldwork and compumain-scheme angles is computed by tations of a fifth-order travers.e apply to a the formula AE = 0.04m' X N, where traverse performed to an accuracy of 1:500 N is the number of main-scheme with the following exceptions: angles. If there are more than six (1) Position. The allowable error in posimain scheme angles in the traverse, tion closure is 1:500. the allowable azimuth error is. com(2) Height. Vertical angles are measured puted by the formula twice with the aiming circle. The AE = O.lrft -yN. mean value should be within -+-0.5 mil of the first reading. The allowable b. Fifth-Order Accuracy. A fifth-order trav error in height closure is +2 meters.. erse starting from existing control must start (3) Azimuth. Horizontal angles are meas and close on stations established to an accuracy ured two repetitions with the aiming of fifth-order or higher. When survey control of the required accuracy is not available, the circle. The accumulated value is divided by 2 to determine the mean fieldwork and computations can be completed value, which should be within +0.5 and the traverse evaluated for accuracy by mil of the first ·reading. The allowable using assumed starting data, provided the trav error in azimuth closure is computed erse is closed on the starting station. The T16 by the formula AE = 0.5rjt X N, theodolite is used to measure the angles. Hori where N is the number of angles in zontal angles are measured one position; verti cal angles are measured once with the teles.cope the traverse. Section Ill. TRAVERSE ADJUSTMENT as simple as it may at first appear. When a 214. General party is extending survey control over long Establishing a common grid throughout an distances by traverse, the traverse may well be entire corps or division artillery sector is not within the prescribed accuracy and still be AGO 10005A 126 considerably in error. This problem is in estimating the tension applied to a steel magnified when several traverse parties are tape. employed to extend control and attempt to tietheir work together. Seldom, if ever, will these c. Natural errors-errors that arise fromvariations in the phenomena of nature, such as parties coincide on their linkage, but, by temperature, humidity, wind, gravity, refrac adjusting the traverse throughout, some com pensation will be made for those errors which tion, and magnetic declination. For example, have accumulated. A traverse executed to a the length of a tape will vary directly with the temperature; i.e., it will become longer as thepres · ibed accuracy of fourth-order must temperature increases and shorter as the temalways be closed and adjusted. An adjusted traverse is one in which the errors have been perature decreases. distributed systematically so that the closingdata as determined by the traverse coincides 216. Azimuth Adjustment with the correct closing data. There is, of a. Deter1nining Azi1nuth Correction. Since course no possible means of determining the the computation of position is in part dependtrue ~agnitude of the errors in angle and disent on azimuth, the first step in adjusting atance measuring which occur throughout a traverse is to determine the azimuth error andtraverse. Traverse adjustment is based on the adjust the azimuth. The azimuth error is obassumption that the errors have gradually tained by determining the difference betweenaccumulated, and the corrections are made acthe azimuth established by traverse (comcordingly. Three adjustments must be made in puted) and the known azimuth at the closingadjusting a traverse-azimuth, coordinates, point. The azimuth correction is the azimuthand height. These adjustments eliminate the error with a sign affixed which will cause theeffects of systematic errors on the assumption computed azimuth, with the correction applied,that they have been constant and equal to equal the known azimuth. For example, the in their effect upon each traverse leg. Blunders, azimuth from a point to an azimuth mark is such as dropped tape lengths or misread angles, known to be 2,571.624 mils. The closing azicannot be compensated for in traverse adjustmuth of a traverse to the same azimuth mark isment. Additionally, a traverse which does not determined to be 2571.554 mils. The azimuthmeet the prescribed standard of accuracy is correction is determined as follows : not adjusted but is checked for error. If the Azim11th error = known azimuth -azimutherror cannot be found, the traverse 1nust be established by traverseperfor?ned again fro?n the start. = 2,571.624 mils -2,571.554mils 215. Sources of Errors = 0.070 mil Azimuth correction = +0.070 mil. The errors that are compensated for bytraverse adjustment are not those errors comb. Application of Azi1nuth Cm-rection. Since monly known as mistakes or blunders but are traverse adjustment is based on the assumption errors that fall that errors present have accumulated gradually into one of the following classes: and systematically throughout the traverse, the azimuth correction is applied accordingly. The a. Instrumental errors-errors that arise correction is distributed equally among thefrom imperfections in, or faulty adjustment of, angles of the traverse with any remainder disthe instruments with which the measurements tributed to the larger angles. For example,are taken. For example, a tape may be too assume that the traverse, for which the azilong or too short or a plate level may be out of muth correction was determined, consisted ofadjustment. three traverse legs and four angles as follows: Station Measured angle b. Personnel errors-errors that arise from SCP 2410.716 milsthe limitations of the human senses of sight TS1 2759.630 milsand touch. For example, an error may be made TS2 3765.876 mils SCP (closing) 2886.617 mils AGO 10005A 127 The azimuth correction is divided by the total a. Determining Easting and Northing Cor-• rections. The easting and northing corrections number of angles. In this case, +0.070 mil ---;-4 = 0.017 mil per angle with a remainder of for the traverse are determined by subtracting 0.002 mil. Each of the four angles will be the coordinates of the closing station (as adjusted by 0.017 mil and the two largest recomputed with the adjusted azimuth) from angles will be adjusted by an additional 0.001 the known coordinates of the closing station. mil each to compensate for the remaining 0.002 For example, mil. Azimuth Correction = known coordinates -coordinates correction Adjusted anDie Station Me...ured anDle established by traverse SCP 2410.716 +0.017 2410.733 = 550554.50-3835829.35 (correct TS1 2759.630 +0.017 2759.647 coordinates) TS2 3765.876 +O.o18 3765.894 SCP 2886.617 +0.018 2886.635 -550550.50-3835835.35 -+4.00 -6.00 c. Action After Adjustment. After the angles (traverse coordinates) have been adjusted, the adjusted azimuth of each leg of the traverse should be computed by b. Application of Easting and Northing Cor using the starting azimuth and the adjusted rections. The corrections determined in a angles at each traverse station. These computaabove are for the entire traverse. The assump tiom> should be performed on fresh sheets of tion is made that these corrections are based DA Form 6-2, not on the sheets used in the on errors proportionately accumulated through original computations. The adjusted azimuth out the traverse. Therefore, the corrections should be computed throughout the entire must be distributed proportionately. The traverse and checked against the correct aziamount of easting or northing correction to muth to the closing azimuth mark before any be applied to the coordinates of each station is of the coordinate adjustments are begun. computed by multiplying the total correction (easting or northing) by the total length of 217. Coordinate Adjustment all the traverse legs up to that station and After the azimuth of each traverse leg has dividing it by the total length of all of the been adjusted, the coordinates of the stations legs. in the traverse. For example, using the total easting and northing corrections pre in the traverse must be adjusted. The first step in adjusting the coordinates is to recompute viously determined, assume that the total length of the traverse is 22,216.89 meters and the coordinates of all stations in the traverse, that the total length of the traverse legs up using the adjusted azimuths to obtain new to TS4 is 3,846.35 meters. bearing angles. Easting correction at TS4 =total easting correction X traverse length to TS4 total traverse length + 4.00 X 3,846.35 22,216.89 -+ 15,385.40 22,216.89 -+ 0.69 meter Northing correction at TS4 =total northing correction X traverse length to TS4 total traverse length= -6.00 X 3,846.35 22,216.89-22,478.1022,216.89 -1.04 meters AGO 10005A 128 l 218. Height Adjustment height correction is determined by comparing Like azimuth adjustment, the height adjustthe height of the closing point as establishedment is based on the assumption that the error by the traverse with the known height of theof closure is accumulated throughout the closing point and applying a sign which willtraverse in equal amounts at each traverse ca use the established height, with the correcstation. tion applied algebraically, to equal the known a. Determining Height Correction. The height. For example: Height correction =known height -height established by traverse= 478.3 meters -477.5 meters= 4-0.8 meter b. Application of Height Correction. The each station but is applied to the difference inheight correction is distributed evenly throughheight (dH) between each traverse station. out all stations of the traverse with any Traverse AdjustedStation height dH Correction height remainder distributed to those stations com SCP 478.3 478.3puted from the longest legs. The height correcTSl 486.7 + 8.4 +0.2 486.9TS2 495.9 +9.2 +0.3 496.4 tion is not applied to the traverse height of SCP 477.5 -18.4 +0.3 478.3 Section IV. LOCATION OF TRAVERSE ERRORS 219. Analysis of Traverse for Errors tolerance; however, the coordinate closure is in A good survey plan executed by a wellerror beyond the limits allowed for the pre trained party provides numerous checks in both scriberl accuracy. computations and fieldwork. However, these b. Isolation of Distance Error. Compare thechecks do not always eliminate errors. On the known coordinates of the closing point with thecontrary, errors are made both in the fieldwork computed coordinates of that point. From this and in computations and are often not discomparison, determine the error in easting and covered until the survey has been completed. the error in northing. Compute the distanceThe surveyor should be able to isolate these (radial error) and azimuth from the knownerrors and determine their causes. Often an coordinates to the computed coordinates. If a .analysis of the fieldwork and the computations distance error has been made, the traverse leg of a survey in error will save hours of containing the distance error will have therepetitious labor and computations. To assist in same azimuth (or back-azimuth) as the radialthis analysis, the chief of survey party should error (fig. 62), and the distance error will be maintain in the field a sketch, drawn to scale, approximately the same length as the radial of each survey as it is being performed. If error. Remeasure the suspected traverse leg available, a reliable map can also be used to to verify the location of the error. Under some advantage. If an error is apparent upon comcircl1mstances, several legs with azimuths ap pletion of the survey, the procedures in paraproximating the azimuth of the radial error graphs 220 and 221 should be followed to isolate may be suspected of containing the error. In the error. An assumption must be made that this case, check the computations for eachonly one error exists. If more than one error suspected leg. If there is no error in the comexists, it will not be possible to isolate the putations, remeasure each suspected leg until errors. the leg containing the error is found. 220. Isolation of Distance Error 221. Isolation of Azimuth Error a. Indication of Distance Error. The azimuth a. Indication of Azimuth Error. The azimuthfor the traverse closes within the allowable closure and the coordinate closure are in error AGO 10005A 129 Radial error of closure 30 meters Bn SCP 30-metererror Figure 62. Distance error. beyond the limits allowed for the prescribed r=w-;-m = 100 meters + 10 mils accuracy. = 10 (range in thousands) b. I solation of Azimuth Error. Compare the = 10,000 meterscomputed azimuth with the known azimuth of the closing point, and determine the azimuth This procedure may be used to determine one error. Determine the azimuth and distance of the radial error. Construct a scaled sketch of or more suspect stations. By trial and error and systematic elimination, the station in error the traverse. Draw in the radial error, and then construct a line perpendicular to, and at the may be located. To locate the station in error, compare the known coordinates of the closingmidpoint of, the radial error. Extend this line through the area in the sketch showing the station with the coordinates of a suspect station and compute the azimuth and distance fieldwork. The station at which the angular between the two. Then compare the computed error was made will be on or very near this extended line. Check the computations and the coordinates of the closing station with the cofield notes for that station. If no error can be ordinates of the suspect station and compute found, remeasure the angle. If the remeasured the azimuth and distance between the two. If the error is at that station, the azimuths should angle compares favorably with the original vary by the amount of the error of the azimuthangle, a multiple error exists and the survey closure of the traverse, and the distances willmust be rerun. c. Alternate Solution. When a graphical plot be approximately the same. If the error is not cannot be made, an azimuth error can be at that station, the azimuths will disagree but isolat ed by determining the approximate disnot by an amount equivalent to the azimuth closure error (fig. 63). Repeat the procedure tance of the station in error from the closing for each of the suspect stations. When the station. To determine the distance, use the mil relation formula (m = w-;-r), the distance of suspect station has been isolated, check the the radial error, and the azimuth error of computations and field notes for that station. closure. Substitute the radial error for the If no error can be found, remeasure the anglewidth and the azimuth error of closure for the at the station. If the remeasured angle commils in the formula. For example, Range (in pares favorably with the original angle, rerunthousands) -to suspected stations = radial error-;-azimuth error of closure or the entire survey. AGO 10005A 130 TSl Correct btry SCP-----; Closure error------~ Computed btry SCP _ __,.., ~-----------.----~-~05 -- Actual route of -----traverse party- --<--computed route of traverse party TS21 Figure 63. Azimuth error. AGO 10005A - CHAPTER 9 TRIANGULATION Section I. GENERAL the DME cannot be used. For this reason, 222. Purpose of Triangulation in artillery surveyors must maintain proficiency Artillery Surveys in triangulation. a. Triangulation is a method of extending survey control through the use of triangular 223. Terminology Associated with figures. Measured horizontal angles and one Triangulationmeasured side of the triangle serve as the basis a. Accuracy ratio is a ratio of linear preci for determining the length of the remaining sion, such as 1:3,000 (meaning that for every sides. A wide range of combinations of known data exists with which required data may be 3,000 units surveyed the error must not exceed one unit), computed in triangulation when thedetermined. These combinations range from scheme closes on a known control point. Thethe simple single triangle with a measured accuracy ratio is computed by dividing thebase and three measured angles to the solution radial error into the total distance surveyed. of two adjacent triangles, from three known The radial error is determined as discussed in positions, with two measured angles in a three point resection problem. Triangulation methods paragraph 213; the total distance is the sum of th'e lengths of the shortest triangle sides may be used at all levels of artillery survey to connecting the starting point and the closing determine the position of control points. It is generally better to use triangulation in situapoint. tions in which the distance involved or the b. Adjustment is the distribution of angular terrain traverse difficult or impossible. More and linear errors throughout a scheme and the detailed planning and reconnaissance is resubsequent recomputation of positions. quired for triangulation than for other c. Azimuth check is the periodic determinamethods. tion of azimuth by astronomic or gyroscopic b. Direct support artillery units may find trimeans for the purpose of checking the azimuthangulation of value in the conduct of connecof triangle sides.tion surveys between position areas and target areas. Triangulation is well suited to situad. The base is a line the length and azimuth tions involving the extension of survey control of which are known, as welt as the coordinates over long distances (e.g., 10 to 20 kilometers and height of one or both ends. The base is per party), such as those required in division used as one side of a triangle to determine the artillery and corps artillery survey. The issue azimuth and length of the other sides. Base of distance-measuring equipment, has, howlengths can be computed between stations of ever, shifted the emphasis at these levels known position, double-taped, or determined to the use of DME traverse. Although the by electronic distance-measuring equipment. DME traverse is a rapid and accurate Base azimuths can be determined by computameans of providing the required control, it tion from known positions, by astronomic is wholly dependent on the successful operaobservation, or by gyroscopic means. tion of a delicate electronic device, the DME. e. A chain is a scheme of several of the same When electronic countermeasures (ECM) are employed or during periods of electronic silence, type of figures connected by common sides, as AGO 10005A 132 a chain of single triangles or a chain of o. Square root of K ( yK ) is used in the quadrilaterals. evaluation of fourth-order surveys to apply f. A check base is a side of one triangle in a t e principle that errors accrue as a functionchain or scheme designated as the place in the of the square root of opportunity for error. Kscheme where the computed length and azirepresents distance in kilometers.muth of the side, as carried through thescheme, is compared to the observed length and p. Square root of N ( VN ) is used in theazimuth of the same side. A triangle side in evaluation of fourth-order surveys to apply theat least every fifth triangle is normally principle that errors accrue as a function of thedesignated a check base. square root of the opportunity for error. Nrepresents the number of stations. g. The closing error is the amount by whichdata determined by the triangulation differs q. Strength of figure is an expression of thefrom known data. Closing errors in azimuth, comparative precision of computed lengths inheight, position, and/ or length are normally a t riangulation net as determined by the sizedetermined when triangulation closes. of the angles. Conditions other than size ofangles are considered in surveys of a higher h. Closure is a term used to describe the order than those encountered in artillery tie-in of triangulation to known control. survey. i. Distance angbes are the angles in a tri r. Summation Rl (~Rl) is a term used to angle opposite a side used as a base in t he solu denote the sum of the strength factors for the tion of the triangle or opposite a side the stronger route in a triangulation net. (The length of which is to be computed. In a chain of single triangles, as the computation proceeds Greek letter sigma is used as the abbreviation.) through the chain, two sides of each triangle s. Triangle closur e is a term associated withare used-a known side and a side to be deterthe amount by which the sum of the threemined. The angles opposite these sides are the angles of a plane triangle fails to equal 3,200distance angles. mils. j. Error in position is the difference between 224. Triangulation Figures the position of a point determined by triangulation and the position of known control. Error a. Acceptable Triangulation Figures. Thein position is usually expressed in terms of nature of the operation, which dictates thethe radial error. time available and the accuracy required, isgenerally the factor which governs the selec k. A figure is a term used to identify onetriangle or one quadrilateral in a chain of tion of the type of triangulation figure to be employed. Acceptable figures triangles. for us~ in artillery survey are as follows: l. Intersection is a method of survey whichemploys one triangular figure in which only (1) Single triangle. The single triangle (fig. 64) is an acceptable figure but two angles are measured. The size of the third should be used only when time does angle is computed from the values of the two measured angles. not permit the use of a quadrilateral. The single triangle does not provide m. A scheme is a broad term applied to a check on the computed value of theplanned triangulation. A scheme of triangulaunknown side as is afforded by othertion may include single triangles, a chain of figures. A survey operation completedtriangles, andjor a chain of quadrilaterals. by the use of one single triangle is notconsidered to be a closed survey. For n. Spherical excess, although not normally a such a survey operation to be a closed concern of artillery surveyors, is a measure of survey, the unknown point should be the amount by which the sum of the three interior angles of a triangle exceeds 3,200 mils surveyed by use of a quadrilateral or due to curvature of the earth. the survey should be extended and tied to a known point. The single tri- AGO 10005A 133 be a closed survey unless a check base measurement is performed and the comparison results in a satisfactory GENERAL check or unless the scheme is tied to existing control. When time permits, the added observations should be made to make the chain of single triangles a chain of quadrilaterals. (4) Chain of quadrilaterals. Use of a chain of quadrilaterals (fig. 66) is favored for the extension of survey control since this figure has desirable check features. In practice, this figure is generally used when long distances over favorable terrain are to be covered. It is used primarily at division artillery and corps artilleryBASE levels. Its use in the field artillery battalion is generally limited to situations wherein time is not critical; Figure 64. A single triangle. which cause departure from estabangle can be used to advantage when lished practice, e.g., BnSCP furnished an obtacle must be crossed in a taped 8 to 10 kilometers from battalion; or where it is desired to strengthen traverse. previously completed chains of single (2) Quadrilateral. One quadrilateral (fig. 65) can be used to extend survey contriangles. trol. Since the length of the required (5) Chain of polygons. A polygon is a side can be computed through two figure of three, four, five, or more pairs of triangles and a check made, sides. A network of these figures, a survey employing a quadrilateral is with central points occupied, can be considered to be a closed survey. used effectively to extend control over a wide area and to tailor a survey (3) Chain of single triangles. In a chain scheme to the available terrain. The of single triangles (fig. 66), as in a of advantages of using a chain single triangle, the only check avail polygons are similar to those of using able is that afforded by the closure of the quadrilateral; i.e., side lengths each triangle to 3,200 mils. A survey can be computed through several operation completed by use of a chain different triangles. of single triangles is not considered to FORWARD LINE A~--------~-=~----~8 DIRECTION OF CONTROL EXTENSION BASE D~==================~c Figure 65. A quadrilateral. AGO 10005A 134 fifth-and fourth-order surveys. The relativemerits of the triangulation method, as compared with other methods, e.g., traverse, arebased only on the nature of the operation andthe terrain and not on the degree of precisionto be attained. The principal factors in thedetermination of the accuracy of triangulationare the average allowable triangle closure andthe discrepancy between the measured lengthof a line and its length as computed through ·the scheme from a previously established base.These factors together with the adherence toprescribed specifications, define the order ofaccuracy of the triangulation. The completespecifications to achieve fifth-and fourth-order CHAIN OF SINGLE TRIANGLES CHAIN OF QUADRILATERALS accuracies are shown in appendix II. 226. Reconnaissance and Planning Figure 66. Triangulation schemes. The reconnaissance consists, of the selection b. Strength of Trianguwtion Figures. The of stations; the number and locations of thesine function is used in the computation of stations, in turn, determine the size and shapetriangle sides. Values computed from the sine of the resulting triangles, the number of stations to be occupied, and the number of angles of angles near 0 mil or 3,200 mils are subjectto large ratios of error. For this reason, the to be measured. During the reconnaissance,distance angles in any triangulation figure consideration is given to the intervisibility andmust be greater than 400 mils. accessibility of stations, the usefulness of thestations for other requirements, the strengthof figure factors, the signals to be used at sta 225. Accuracy of Triangulation tions, and the suitability of the terrain for baseTriangulation is performed in both artillery line and check base measurements. Section II. SINGLE TRIANGLE 227. Fieldwork T2 theodolite with agreement between a. The fieldwork for a single triangle is perthe positions held to 0.05 m:il. formed to determine the size of the interior (2) Verti•l angles. Vertical angles arehorizontal angles, the size of the vertical measured once with the telescope inangles, and the length and azimuth of a side. the direct position and once with theFigures 67 through 69 are samples of field telescope in the reverse position fornotes taken during triangulation. both fourth-and fifth-order surveys.Reciprocal vertical angles should be (1) Horizontal angles. At each of the three measured in order to points forming the triangle, the cancel the horizontal angle between the other effects of curvature and refraction. two points is measured. In triangles (3) Base length. The length of the side offorming a part of a fifth-order survey, the triangle to be used as the basehorizontal angles are measured one may be determined by computationposition with the T16 theodolite; for from known coordinates, by double fourth-order survey, horizontal angles taping, or by using electronicare measured two positions with the distance-measuring equipment. AGO 10005A 135 t!!llf~ t?F ~Rrl': .s.sr. {T/lfPNJN H/E!TII£1?: CLUK-!(CT ~.4'P.RV£-4: .r&r,;.bv..<:s DES GNATION TRIANGULATION DATE /5 Jl//. 19 59 I 1101'1/ZQAIT.fL. ':!f_lf!liRED a/IME~T£0 {)1!~~£.! STATION R bf_{'!i") YERT4-t?) JIF!rr4-lh/) /'t(ETEif$ iZ.MK. I /358." ff!f711C4L A '6L£ tbh'8_.Et?, 7.0..-Y 15 -r.Z.Z.1/1/S: 1!2. PI: (f'JtiES!, lf';fltfltJ.J ~C?r 7 V.-f' 8~~.:::9 /?.Ell ##. 4-lt?.B{~ Tt?#.J£h'l> A'P~ .Z .#IL. ~ A/tJ/1 'P C?r s.SV..-4. &LL EIT/?EA ~TIP pc Tt/~ -R /S ~-'Iff# ,A/;18/r.. $ALL 2 ~715.5 97J.t? 1'/1?5:5 ,. 11?7. 7 85/..Z:) /124/,{. !?EIJ / 8'/?LL 2 l'/f16.t1 l'#.t? ~~7. z L_L_ [$51. 37 ;t£r PI#. .4- 1?/.S.IJ_) ,.t?S..y ,..?7.-f) ~1.3_]) I I I ;HIT I IZ/7. S -,?3.6" -t?/.3 h'EO 2 .ttr.J/1.6" -Pif.. P -ot. e 12/7.2) -tJJ~ -tJ/.6) 1', .B,4LL t*l#. A \ \ ~ I I jp09. e? -tJ/.d ,./.2 I?ALI. JIET ~ Lt?/8.5 -0/.t? ,./.2 \ ~/) Jlh' .4-Q.!P9..;J @llJ [(!/,~ \ \ \ /~ '-' '\ I I.-- EAST Figure 67. Recorder's notes for aiming circle triangulation. (a) Computation from known coordir meter requires two coarse and four nates. When both ends of the line fine readings; with the DME, the line should be measured in both selected as the base are known sur vey control points, the length of directions. These criteria apply to the base can be computed using both fourth-and fifth-order DA Form 6-1. The stations selected surveys. must have been established as part (4) Base azimuth. DA Form 6-1 may be of the same survey net and should used to determine the azimuth of thebe of an order higher than that of base when both ends of the base are the survey being conducted. known survey control points. When (b) Taping. The base must be doublethe base length is determined by taptaped to a comparative accuracy of ing or by using electronic distance1:7,000 for fourth-order survey and measuring instruments, the azimuth 1:3,000 for fifth-order survey. must be determined by astronomic (c) Electronic distance measuring. The means or, when celestial bodies are length of the base of a triangle can not usable, by gyroscopic means. be rapidly and accurately determined by using electronic distanceb. The complete specifications for fieldwork measuring equipment. Base length for fourth-and fifth-order surveys are shown in determination with the Telluro-appendix II. AGO lOOOoA 136 CJ,,·~ f. ol p .. ,.o~"i : S~+ J.,es(}iJs«rtJ~r · s,t H.t',e~ DE SIG NATIO N TRIANGVLRTtPN' DATE .2¢ J/)L 19 btl YMnt It ,. ~~or' Cl'" . " !1. Jl_,,· .. -"+aJ Ye.r .. ,ca.l iler.f.,ce..l S+..+I~H I ~ n..;Js n.e-.n ,~._.,.;,..1 REM itiRIOO /. 0 Tom ;~ loc-..+ ./ SP/H N .! f. -t1errifl-A ".. ,..,F< 3:l ()/. 0 ooo/. o 7S'M J1, .! 1 ,q,. ..,..s 1(.1 . 1> ic.l<. /s .. e .. feJ 3 M TPM Mn 4 cP3 .i' (!7s-.i) E •I t. o...k IS <-•fu( 'IsM s • SE" RJ """'e.lfe. • ! 6riJ~e . """:! IS V•e•fel eM w I f H<>.rr'1 D 73'I.K 15J'I/. 'I +/5. , ,1/1/&;.tt.;.ce ~'""""' Tt~m +o lJ1Gk 1$ 'fp() , .2 J'hlH,.,.,.., D ()()~/. 0 Ve.r f;c.•l "'"''J~s ,... +-)I r . R. ;J:tc/.P """'· p P/Gk. Mn ..l\. ltJti. S' G·v ~~-.D /{)92. .5 /(,/f. .5" -I'~· .5" J -)I. r--)(-l\ -x-x-x-xII R '/29:Z.S ;ct:l. S" '11r;. 5" -I'1. .5"' / ~IIlUCY J I I I / \ ,.,,. .D occ/.0 I J I _, / \ v / I 3:ltJI. tJ ()()tl / . I) R I IL /1--~ / I ll#n·f Mil-~ Vi:J 7'/.5" (+:J. i) I /f- 1\ I I !;{_, \ I /)J~k D t37f.S ;59,. / ~ DICK + 3 . 9 R ~s7S.S' /3 7.5'. s '/N3. '1 -r 3. 'J ~ .. ~I I r---r---\ \ 0<:J ~I r----_\ ~I ~, TDiil q:l I -_/t1Ef'IRI RD I l1l Figure 68. Recorder's notes for fifth-order, T16 theodolite, triangulation. 228. Computation of a Single Triangle known and all the angles have been measured,the length of either side CA or BA can bea. The purpose of triangulation computations computed. is to determine the coordinates and height of an unknown point (fig. 70). The requirements To solve for side CA: To solve for side BA: for these computations are azimuth of the base, b a a clength of the base, value of the distance angles, sin B =sin A sin A-sin C and a vertical angle from one of the knownpoints (A or B) to the unknown point. b sin A = a sin B c sin A = a sin C b _a sin B a sin C b. The mathematical basis for determining C= -sin A the distance is the law of sines (fig. 71). The sin A law of sines states that in a triangle the sides c. After the length of the desired side isare proportional to the sines of the angles computed from the law of sines, the azimuthopposite them or, a b c of the desired side is determined by applyingsin A sin B sin C the measured angle to the known base azimuth.The vertical angle is known from the fieldwork. The two parts of the formula that involve both The elements essential for the computation of known data and required data are selected, and easting, northing, and height are now known.the unknown element is isolated on one side of The remainder of the computations is identicalthe equals sign. For example, if side BC is with the computations in a traverse problem. AGO 10005A 137 I CHIEF OF PARTY : S&T MdJZI:IIIRLD ~ WEATHER : CL£ AR -COOL OBSERVER : SGT KNOTT I INSTRUMENT ND T.l.41-JKil RECoRDER · CPL THIEN DESIGNATION TRIANC:.ULATION DATE 25 JUL 19 /11/tiZI>NT/IL VERT I CAL VERTICAL STAT /II/II T ~ MI~S MfAN KEAOIHG .\MILS REMRR~s DoOG.E . D oooo. IO~ IS't.7. 11./' +32..S'S'i FIRS PIJSIT/ f>/5 IJF T ""'" /'OS/ llf>/S. B SE LENGTH CIIPI>O -POOG£ 3¥0'1. 'I M (8T 1} R 3~00. 1~1 oooo. /13 lfl'.3~ . i'll +32. 111 CADDO MN ~h:J.I.I./11 +32.. Y1lJ OOI)GE !::::? PoTAn> D /1.2.1.518 l/.2.1.52'1-1~00· '"' -() . 91.1. .A-.2.'1M 1180 £ STA. .R 1/l:l.l. 5.3/ '17'f'f. 017 -o. O. 1/'1 ) '(: o. '¥7'/-) ? k- 2.1./lt'l AS vE STII AR&uc.I:L~ D 3'111· 91.&. ~II. 11.7 ISS/. 712 +1/8.208 R nn11,.1 1/1'11. If.'/ +'II'. ''" 08$ERV D J/1 .117" 4,f/1llc.K e:" CADDO MH 1712. Sf/, ) IJ£ ST"A y ICIOW,_ D i,s7t.l/. '1-7. S7t.ll.ttl.; /t.2/. .7fP -.:u..1'10 /(IOWAR 2sH.t11. 4176.832. -.:J/. !ft.'8 .A -:u.:17'1) ~1--'f. IM ...__.... 3 · fM ;;;;;~"' t.M A-i-~· AT CA 00 HEIGHT ~F SIG#A HI =I. .S M n?,tf'y "~'/ Figure 69. R ecorder's notes for fourth-order, T2 theodolit e, triangu lation. tolerable limits for the order of surThese computations are fundamental to all trivey being conducted, the difference isangulation operations from the simple single divided by 3 and listed by each stationt riangle to the most complex quadrilateral or under the CORRECTION column,central point figure. preceded by the appropriate sign. d. The form provided to simplify and sysWhen the difference is not evenly tematize the triangle solution is DA Form 6-8. divisible by 3, the remainder is disThe front side of DA Form 6-8 is designed for tributed to the larger angles. The the solution of two single triangles. In figure results of applying the values in the 72, DA Form 6-8 is divided into four major correction column to the values in the parts labeled A through D. These parts are observed angles column are listed in described in (1) through (4) below. the CORRECTED ANGLES column, (1) Part A. Spaces are provided for entry together with the total, 3,200 mils. of the three station names and are (2) Part B. Two determinations essentialkeyed to a triangle sketch. The base to solving t he problem are made in of the triangle is always the line CB. part B. In the upper right corner ofAngles from the field notebook are part B, spaces are provided for deterrecorded in the OBSERVED mining the logarithm of the UTMANGLES column. The sum of the grid length of the base. The block toobserved angles is compared to 3,200 the left is used for the solution of themils; if the difference is within the AGO 100 05 A 13 8 DESIGNATION TRIAtJGULATION_ccaw}oA TE 2 5 .J/J L 19 - H~R/Z.DNT~ MUoN ST.O,T t o l'( T ~ M l t. S MEAN HO!'~~~~·L KEM ~lfKS DOD6E. .. R 41-Koo . 2 t 3 "2.1. if. II S£CtJN[) PtJSIT I IV D //,00-.227 "00. 2. 20 1/.2/. '1.11 .sn TltJIII C 000 I S LoCA>-.e 0 1111 r; ~ SOUr// CADDO MN Jft,:/./. 1./31~ rJ(,:z.t.ll:l/ ,t)lf'/.Jt/0vE ,t;R£. ~ t1.C FT. /t.L /J'I,"f TRI?Y IP..i -n. '"'"'() lt. IH!LE. .S. t7F tJVlJ.!J /?1/) {;E /?lltY6 IE CEAITl.r111. oAI PoTA.\ o R ()03/ . .(.21 3 2 21./.3 231.0.119. #IS/I.tSir" ?tMYT ~rC,.fl/.sls-.Y ..r'..t~ L Jll. "~'"W.11TTA 0 J).:J./. 1.33 .2 3f.O.'I'll C ,f'Ji"£-f'. STAT/~v I S I N16'/f"tJAI.? P.t.t/6 ffT IAI CADDo MN z3t.o.-ii. f) ti·u. o. 4~D ' CtJ/JCR6 TE .8LO It' FL , I.S vw;r/1 'r;,£7()t//11/J. / () "...r ' " ARSoo:·L...~ R 12382. 072. 558:Z. ./J11 1112.51, K/rf if I IS ()J./) I7Aif'6£T. /Alii;( 0 is5r:l.-OI3 1Ut. .S2'r Rhf.tl.t ·s .roi?Jc 'Ill TKI ''-CADDO ''"" '1712.5:1.~~ n712. .52.o) £i11113 lt .s .z .. ~IPE 5T, :KIItlt<. I ' ABovE ~li'OtJNIJ ON W 10£ tJI" T/r/1 11... K IOWA ·-R. ll/1/,11, S'lllo9,:;4.'" 0 o11.1U,I/ ~";:,.r...~ p:~~~ I I KIOWA ", I U~"'' ' A' " ~ ,;:;-; ~!KMa>~ --~ ,,.. /I f\~ i ~~RM it.Z. I ,, _1 \ ... ~~ \ I -I ,\. RM-.,', '6-f:"' ;;; · ,(', - ~'Y Figure 69-Continued. A law of sir.es for either side CA or BA. 4 · 9~0.0 or\ lnstructicms relating to the side not being sobed should be line~ out. (3) Part C. Part C provides spaces for det ermining the azimuth from B to A or from C to ·A. This azimuth must 4-• 1490.0 or\ be determined before E and N can be 4-• 760.0 or\ computed. The base azimuth must be known and expressed as C to B, if coordinat es are to be computed through side CA, or as B to C, if co Figur e 70. Computation requirements. A ordinates are to be computed through side BA. To the azimuth is added either the corrected angle at B or the corrected angle at c, subtracted from 6,400 mils. When the corrected angle at C is used, the auxiliary block TO FIND STATION ANGLE AT C is used. The sum is the azimuth from C to A or from B to A and will be used Figure 71. Law of sines. to determine the bearing angle. AGO 10005A -'---------------------- A 8 ! I " " s•• i: rut~ ml 1 ,..---1--i---+------1 1--1--- 1--T--+-~1----,-,1 ( J JOf 4J'"'lOG"Ki! ! ca.... .. 11,..,1 1 I D ctu..::Cc lsu uo• ' I I ! OOCLt•T C l . t ... I ,.• I ,.• I Vt•t d st a-rWD SI I - t~J. (U UO('II) :miM...:.:msu~'' t I ' t I I I I I . - I ILG(IUI( $UM(tJO'(rJ t ~ I I I I I ' . t 1-7.ru 1s...,. •lc~~h.:E~I,-4. , . .' ·~ I I I I I I I d.. ~2!~~(ntt {:A~~;L m I " I I I I I I I. ~~·~I I l~l'(~~n, .. l~·'m ! I I r I I I I I [1-~ I ~ lrM~I ~~r'u~~ ,.... :!: =~ ~~I If!::. I l ~m= ' l ! ! Figure 72. Main parts of DA Form 6-8. (4) Part D. Part D is used to reduce the azimuth to a bearing and provides spaces for the computation of dE, dN, and dH and the application of these values to theE, N, and H of station B or C. Lines 6 through 10 are used to mean vertical angles which were observed in both directions (reciprocal). The computations are complete when the coordinates forE, N, and H of the forward station have been determined. e. For height determination, the vertical angle is measured reciprocally to the height of instrument (HI) at each station or, if the distance is too great, the vertical angle is meas- E Height of point C Is known. // indicates forward line. Figure 78. Route of trigonometric height computations. ured to the height of a target erected over the station. When the measurements are to HI, the heights of triangulation stations are computed on DA Form 6-8. If the length of the side is greater than 1,000 meters and if the vertical angle is not measured reciprocally, the table of curvature and refraction corrections on the back of DA Form 6-8 must be used. The log length of the side computed is used to enter the table. When the vertical angle is measured to a target erected over the station or to any point other than HI, the height of the unknown station is computed on DA Form 6-2b (fig. 59). Instructions for the use of DA Form 6-2b are on the back of the form (fig. 60). Height control is extended along the forward line of each t riangle in the scheme; therefore, the computations for height control follow the same route (fig. 73) as those for coordinates. f. The selection of side CA or side BA as the required side in a single triangle is governed by the strength of the angles at B and C. The side selected is the side opposite the stronger (nearer 1,600 mils) of the two angles. If the coordinates of only one end of the base are known, it may become necessary to use the opposite end of the base for the occupied station. Coordinates of that point are computed as in traverse. Figure 74 is a completed DA Form 6-8, showing the computations for a fifth-order triangulation scheme. AGO 10005A II I > I REPLACES OA FORM 6-8, 1 II OY 53, WlllC~ Wlll BE USED UNTIL EXHAUSHD. COMPUTATION -PLANE TRIANGLE COORD I NATES AND HEIGHT FROio! ONE SIDE, THREE ANGLES AND VERT ICAL ANGLES Figure 74. Completed DA Form 6-8 showing fifth order triangulation computations. ~ - Section Ill. CHAINS OF TRIANGLES check comparisons are 1:3,000 and 0.1 mil X 229. Chain of Single Triangles 4 yiNwhere N is the number of angles used to a. More distance can be covered and more carry the azimuth to the check base. survey control established by joining single d. Computation of the chain of single tritriangles together with a common side. Triangles is performed on DA Form 6-8. The angles so connected are referred to as a chain form is used as described in paragraph 228 of single triangles (fig. 75). In all the triangles except that the taped base block in the upper except the final triangle of the scheme, the side right corner is used only for the first triangle common to two triangles is called the forward in the chain; for subsequent triangles, the log side and is the side whose length is determined of the side to be used as the base is used from in the computation. This side then becomes the the preceding triangle.base of the next triangle in the chain. Although the chain of single triangles offers but one e. A chain of single triangles does not route for the computation, strength of figure is provide sufficient internal checks to guard against survey blunders or a means of estimat a consideration in planning the chain. ing the accuracy of the work. If convenient, the b. The size of the distance angles in a tri chain of triangles may be closed on a second angle is used as the measure of relative known survey point and its accuracy may be strength. The strength factors of a triangle are computed by the traverse accuracy ratio determined by use of a strength of figure table formula. If this is done, the length of the sur(fig. 76). The distance angles of the triangle vey used in the accuracy computation should be serve as arguments for entering the table-the the sum of the lengths of the shortest triangle small distance angle dictates the column ; the sides connecting the starting point with the larger distance angle, the row. The smaller the closing point. The lengths can be determined factor, the gre~ter the relative strength of the from a map or computed by slide rule if they triangle. were not computed in the scheme. In general, c. When the sum of the strength factors in a a base check is simpler and provides an chain of single triangles exceeds 200 or at every adequate check. The length of the terminal side fifth triangle, a check base should be measured. of the final triangle is measured and compared If the difference between the computed length with the length computed through the chain of and azimuth and the measured length and azitriangles. The allowable closing error in posimuth is within prescribed tolerances, the tion or the results of a base check are specified scheme may be continued, using the measured in appendix II for the order of survey being data. For fifth-order surveys, the computed performed. In either case, if the chain of tri angles consists of more than five triangles, thelength of the check base must agree with the measured length within 1 :1,000 and the comlengths of additional sides must be measured so that there are not more than five triangles puted azimuth must agree with the astro or gyro azimuth within 0.1 mil times the number between measured sides. The azimuth of the of angles used to carry the azimuth to the terminal leg should be determined by astrocheck base. For fourth-order surveys, the nomic or gyroscopic observation at the earliest -practicable time to guard against degrading the azimuth due to lack of refinements in the method of computations. Error in azimuth is determined by comparing the trig list azimuth or the astro or gyro azimuth with the azimuth from the scheme. The number of main scheme angles for the purpose of the check is equal to the number of triangles in the scheme. If the comparison of the measured values with the computed values agrees with the specifications Figure 75. Chain of single triangles. AGO 10005A 142 I 0 ..c> 0 Mils 150 200 250 300 350 0 0 400 450 500 550 600 700 800 900 1000 1100 1200 "'> 1300 1400 1500 1600 150 605200 465 334 iI 250 391 272 212300 347 233 176 143350 320 210 155 123 104400 300 192 139 109 91 78450 283 178 127 97 80 68 58500 272 169 119 90 73 61 52 46550 264 162 112 84 68 56 47 41 37600 257 157 108 80 64 53 44 38 34 31 700 245 147 99 72 57 46 38 32 28 25 20 800 236 139 93 67 52 41 33 28 24 21 17 13 900 229 133 88 62 48 38 30 25 21 19 14 11 9 1000 223 129 84 59 45 35 27 23 19 17 12 9 7 6 1100 218 125 81 56 43 33 25 21 17 15 11 8 6 5 4 1200 215 123 79 55 41 31 24 20 16 14 10 7 5 4 3 2 1300 211 119 76 52 39 29 22 18 15 13 9 6 4 3 2 2 11400 207 117 74 51 37 28 21 17 14 12 8 5 4 3 2 1 1 1500 205 115 72 0 49 36 27 20 16 13 11 7 5 1600 202 112 71 3 2 1 1 1 0 0 48 35 26 19 15 12 10 7 4 3 2 1 1 0 0 0 01700 199 110 69 46 34 25 19 14 12 10 6 4 3 2 1 1 0 1800 196 108 67 45 33 24 18 14 11 9 6 4 2 0 0 ' 2 1 1 0 ! 1900 193 106 66 44 32 23 17 13 0 11 9 6 4 2000 190 104 64 2 1 1 1 0 42 30 22 16 13 10 8 5 3 2 2 1 1 2100 187 102 63 41 30 22 16 12 10 8 5 3 2 2 1 2200 184 99 61 40 29 21 15 12 9 8 5 3 2 22300 180 97 59 39 28 20 15 11 9 8 5 4 3 ! 2400 176 95 57 38 27 20 15 11 9 8 6 4 2500 171 92 55 36 26 20 15 12 10 9 7 2600 166 89 54 36 26 20 16 13 11 102650 164 88 53 36 26 20 16 14 12 2700 161 86 53 36 27 21 17 15 2750 159 85 53 37 28 23 19 2800 155 84 54 38 31 26 2850 153 85 56 42 35 2900 151 87 60 48 2950 153 94 71 3000 163 112 3050 202 Figure 76. Table for determining strength of figure factors (mils).w -"" A A FORWARD LINE BA FORWARD LINE B 1>.B 1:>. A--------A 1:>.----------t>. II /// / _,/"I i',','-............., \\ 4 I / / / / I ' ....... \ I / / / / I ' ' '-............. \ I I / / ' ' BASE / D // BASE 1:>.------------------1>.""-....,_ c' FORWARD LINE FORWARD LINE t:r--------1:>. 1:>.--------1:>.I ,.............. \ /,I // ' ....... ', / // '/ / ' _____!!ASE___ // BASE BASE 6 A-------- OTHER CHAIN OF TRIANGLES ONE CHAIN OF TRIANGLES IN THE QUADRILATERAL IN THE QUADRILATERAL Figure 77. A quadrilateral separated into two single chains of two triangles each. in appendix II, the scheme should be continued, surveys, both diagonals of the figure must be using the measured data. Adjustment of comobserved. Each diagonal divides the figure into puted values to measured values may be pertwo triangles with the diagonal common to both quadrilateral formed at the SIC using machine-programmed triangles. Figure 77 shows a divided by its diagonals. computers. b. The requirements for the computation of a 230. Chain of Quadrilaterials quadrilateral are the same as those for the a. A quadrilateral is a four-sided figure used computation of a single triangle; i.e., the length for the extension of survey control. In artillery of the base, the azimuth of the base, and the Distance an9les" . 1510a'l -1070a'l =I Distance an9les =· 1510ril-980ril =2 Distance an9les = 1690tfl-800a'l =4 Distance an9les" 1690a'l-890ril =3 =6 Total stren9th of fi9ures =4 Total stren9th of fi 9ures Ri R2 Figure 78. Determination of Rt and R2 chains. AGO 10005A 144 -------·----- - 8 ... .... ..."' ~ REPL 4C(S 04 FORM 6-6, 1 MOV 5), lfHI CH WILl 8E USED UIITIL (XHfoUSTED. COMPUTATION -PLANE TRIANGLE COORO I NATES ANO HF.I r.~T FROM ON_E SI ~E , THREE AMjLES AND VERT ICAL ANGLES ._. Figure 79. Solution of Rl chain, fourth-order survey. J ~ <> ·--T--; L TOc:oa.PUTI WMI .._ ~ AUXILIARY COMPUTATION ----I IOCOII,UliWCil~ ::;...r ___...,--~ ! lt+Ui oL~ "OI;;. _....- TOCOIIf'\ITIUOl ._ UK"--~Trtl .. ::?""'"' ·t \U1UL04;W llfao LOC tc:l 0 Figure 80. Solution of R2 chain, fourth-order survey. .... I 0~ ....-... ~-· coordinates of at least one of the ends of the base. The side of t he quadrilateral opposite the base in a single quadrilateral or the side common to two quadrilaterals is designated the forward line. The forward line is computed through both pairs of triangles. This gives a basis for checking the length of the forward line. Failure of the two computed lengths to agree indicates either an error in computing or an error in the fieldwork. c. One of the pairs of triangles is of better geometric shape than the other, thus giving better relative strength of figure. The pair determined to be the stronger is designated the Rl chain; the other the R2 chain. Positions are computed only through the Rl chain; the forward line is computed through both chains. The selection of Rl is based on strength factors determined from the strength of figure factors table (fig. 76). The two distance angles of each triangle, rounded off to the nearest value tabulated in the strength of figure table, are used to enter the table. The factors obtained for each triangle of a given chain are then added, and the chain containing the smaller total value is the stronger, or Rl, chain. Figure 78 illustrates the determination of strength factors. d. DA Form 6-8 is use for the computation of a quadrilateral. The two triangles forming the Rl chain are computed on the front of the form; the triangles forming the R2 chain, on the back of the form. Only the log length of the forward line of the R2 chain is computed. Spaces are provided on the back of the form for comparing the log lengths of the forward line, as determined through Rl and R2. If the two log lengths agree within 5 in the fifth place of the mantissa, the computations and fieldwork are considered to be correct and E, N and H can then be computed, using the Rl chain. If the comparison results in a greater difference than 5 in the fifth place of the mantissa, the computations and/ or fieldwork must be checked. Computations of a quadrilateral are illustrated in figures 79 and 80. e. A survey operation in which quadrilaterals are used should be tied to existing control when possible. A completed quadrilateral is AGO I0005A considered to be a closed survey; however a check base should be included to obtain a measure of the accuracy of the scheme. Check bases should be included at every fifth quadrilateral or when the summation of the Rl values in the scheme exceeds 200. f. When it is impossible to observe the diagonals of a quadrilateral, the central point is used. Two central point figures commonly used are shown in figures 81 and 82. Central point figures of six or more sides are not generally used because of the excessive time and the number of personnel required to accomplish the fieldwork. The solution of the central point scheme is similar to the solution of the basic quadrilateral. The Rl and the R2 chains must be determined. In figures 81 and 82, each scheme contains two chains of triangles, one going clockwise around the central point and the other going counterclockwise. In figure 82, if .AB were the base and DC the forward line, Figure 81. Central point quadrilate1·al. c E A Figure 82. Central point p entagon. the chain of triangles going clockwise would strength of the chain of four triangles when contain four triangles and the chain of tricompared with the relative strength of the angles going counterclockwise would contain chain of three triangles, may make it the R1 only three triangles. However, the relative chain. Section IV. INTERSECTION 231. General Intersection is a method of triangulation in which only two angles in a triangle are measured. The third angle is determined by subtracting the sum of the two measured angles from 3,200 mils (180°). 232. Specifications See appendix II for specifications and techniques in triangulation. 233. Intersection Field Notes Intersection field notes are maintained in the same manner as triangulation field notes (figs. 67, 68, and 69). Section V. 236. Three-Point Resection Three-point resection is a method of obtaining control from three visible known points. The fieldwork required for the solution is relatively simple. However, before the fieldwork is begun, several factors must be considered. A map reconnaissance is of prime importance. In figure 83, points A, B, and C are the known points and point P is the occupied station for which coordinates are to be deter- A I I I 234. Limitations As in triangulation, no distance angle in the triangle should be less than 400 mils (22% 0 ) or greater than 2,800 mils (157%o) ; an angle between 533 mils (30°) and 2,667 mils (150° ) is preferred. The only exception to this is when intersection is used in target area survey when the apex angle should not be less than 150 mils and should preferably be at least 300 mils. 235. Intersection Computations Intersection computations are the same as those used for triangulation except that, on the DA Form 6-8, the unmeasured angle must be computed and the angles in the triangle are not adjusted. RESECTION mined. All points should be selected so that angles P1, P2, C, and B are at least 400 mils (22% 0 ) and preferably greater than 533 mils (30°). In addition, if the sum of the angles P1, P2, and A1 is between 2,845 mils and 3,555 mils (160° and 200°), no valid solution is possible. Fieldwork consists of measuring angles P1 and P2 and the vertical angle from P to the known point for which the height is also known, preferably point A. P~2 --------p -------- c --------B Figure 83. A three-point resection. 148 > 8 0~ >"':> Jl REI' EAT (:10) COMPUTATIOH-cDORDIMATES AHD HEIGHT FROM THREE-POIHT RESECTION f{p 1'1 70 J2 REP'EAT (7) IL '2. 8fc 1 AZIMUTH A TO C SKETCH: JJ (Jl + J2) (FROIIII AUI COIIII' ON REV) If Si. 0.2. 2'1 1/-2. Sh 2 :uo• OR UOOJ U lief' OR J20Chil 32 00 00 <\W' e If (ll 1$ · J5 REPEAT (1J) MORE THAN (i) .wth-m :J..'l i/-2. 51, ] LEU THAN (f) CH+UI II I$/,I 02 .. , ' . l6 ( :WI -(:1.5) "' ANGLE A2 AZIMUTH A TO B \V < .~_ ··· 2.157 702. . 94 "3 83i:> S'48~ T/7. 3.2-'f~'f.. AZ A TO B REPEAT (4) It{. bl S.J.. AZ TO BEARING VERT 4 P TO A STA AMGLE WITH SIGH REVERSED 2. 57 'f'f 3:Z oo 00 J¥ " 37 ··~ 7 1:>32.. 73 ··b B'IS. if-9 ·4J . . ' ;: I I I I I(~J ~;~ 32. 00 00 DIFFERENCE IN HEIGHTS OF T ARGET AM) INSTR UMENT FROM GUIDE ON REVERSE 'STATION P ** 'f. ~ O AZIMUTH IIHf* 01 •ss~:33S~ h7 "3 835 9.53 . 38 " 373.S ~~ P TO A CORRECTION FOR CURVAT\JRf AND RE,.tACTION FROM TABLE ON REVERSE CHECKER F/f/C.I< ISHEET o• SHECTS i; '1-9 18 9i:> COMPUT£R IJ.IUDIUM - .. PREVIOUS EDITIONS OF THIS FORt.4 ARE OBSOLETE. GP'O 10.-1 Z1 DA .~~~... ~ 6-19 Figure 84. Solution of three-point resection, fourth-order survey. 00 -"'0 -0~ 0 0g"; > TABLE· CCRRECTION F~ OJRVATUR£ AN D REFRACTION AUXILIARY COMPUTATIOH (NO lNTERPCll.ATI ON NECES SARY FOR ARTILLERY SLJW£Y) AZIMUTH AND DISTAHCE FROM A TD B AHD A TO C (SIGN ALWAYS MINUS) Co"(M) 5TATKIN E COot!DtNATE N COOROINAT£ ~~+~~~: Log Side (M) Con(M) Log Side (M) 3.019 .I 3.71 2 3."136 2.0 PAC • SIJ.ft, 702.~'1'1-• .3,83b Ki~-8!87 3 .230 1.8 .2FROMSTATIOIOA 2.5 3 .32:2 .3 3.184 3.824 3.03.386 I TOSTATIONI MAN • 553 92.5~ 95 • 3 837 3.3~!'15 .. 5 3.8:>1 3.5 3 .435 3.886 4.0I ::.;~~~~.. THAN. •• 5'1" 702! 9-st .. 3,83'-, f'f8!87 3 .413 .6 3.912 3.508 .7 ent and wget "'* follows: =---- IH (IS) ON FRONT) (ENTER LOG GRID DISTANCE A TO 8 ............... !;:;~~:::: :::::~ ~::::::t .;:;t:· ::::;:;:;~ ::::::::;:;:~; ;:;:;:;:;:::;?;:::: .;:;:;:;:;:;:;:;:;: :;:;:;:::;:;:;:;:;:;:;:;::;:F.:::::; :;:;:;:;:;:;:;:;:;:;:;:;:;::;:;:;::::::::::::::::::::::::::::::::~::::}:::~::;::::::::·:; :-:=:~-;:;:·:·,·.·.·. . ···:·:·:-:-;.;-;::;::::;:;·;::~:;:;~:;:;:::;::: Known or Estimo~ted I+ 2 ,IS :;:;;:~: .:::::::;:;:;:;~ ;:;:;:;:;::=:~(:;~:;:: dE+ Height of Target dN + STATION E COORDINATE N COOROIMA T E :=~ Measured Height I I S ol baument -.2 . Algebr.a ic Sum .a and b I 1 FROMSTATOINA P~C • Sl/.f.. 1b.:l.~ '?'! • 3 f/3~ 8'/8~ 5'7 *---I (Emer. with sign, in block marked * J 0 . 0 1 TOSTATKINC RE. Y c 55.1 318'! r..s c 3 5'35 t2"1~58 r.nt e r correction for curvanue and refraction an block marked ** LIMITA TIONS: I ::E~~~~~STHAMC AA 5J!I. , 70.2.~9~~AA : I ~ Angles P1, P2 , 8, and C should be greater th.an 22 1/2° (400dl) or ucuncy may fall beloll a ancbrd. --• OF AA 1~ BLANK. USE A -c. SIGN -d•Ef? 1 • 4N -dN - IFAAISfiLLED,USEC -AA, SIGM 1 1 <>rl 7/' ldN I+ I /I 1/'fl 2'fldE -41:'!'-'7~-"'------~ 1 RESt.n.TS: I I ANGLE HAVING LOG TAt~ 13 43: 99 Coordinate~ and height ol station P. LOG dE l3.3.25oI 7'f(,I.J IEARINC A TO C Azimuth from sUit ion P to s~tion A. I I DETERMINE AZIMUTH FROIII 32 00. 00 I FORMULAS: 3 2 3 r" 711 'f.'., BEARING IY PLOTYING dE LOCdH AND 4H OH SIC ETCH AS GUIDE T an z = AB sin P1 AB sin P1 LOG dE-LOG 4H• IS st.. o2.. f 1/ 2 (S.q ii more dun{1 :0~o'l }: I 1/ 2 (8-tq b more th&n {1 ~~r/l}:LOG TAN IEAJUHG A TO C Tol n 1/'2 (B-q = Tu (Z-450, Tan 1/ 2 (B+q • ~ (.;,1 7" ""' 13 43; 98 T,nz = ~ AC sin P2 T.a n 1/ 2 (C-B} = Tan (i.-45~ T•n 1/2 (S.q IF dE IS LEU T".AH 4H If dE 15 MORE THAN 4H --..... ~~r;t,}: I I/2 (B-tq is leu than { 1:00:r;t,}: f 1/ 2 (S.q illeu than { 1 REfEAT LOG df 3 ~ 82.5: 1'1'-1. RErEATLOG~ ~ Tan 1/ 2 (B-q = Tan (Z -45°) Tan 1/2 (S.q T.tn 1/2 (C-8) : T•n (Z-4Sa, TAn 1/2 (B+Q AC sin C AP = ~ LOG SIN IEARINC A TO C 9~11"';!31/.7 r...OC COSIEARIH~ sin P2 ~ LOG ~coslEARINC • LOG o(E-LOG SIN BEARING: 3~8.19 :t.,/9 ~RIDDISTANCE A TO C I I -;-_ i. = an auxiliary angle requin::d only ill the compu~tion (.tlways between 45 And 90 depees). LOG GaiD OIST AMCE A TO C (ENTER LOG GRID DISTANCE A TO C IH (12) ON ,ROHT) Figure 85. Back of DA Form 6-19. 237. DA Form 6-19 ing angles R1, R2, Q1, and Q2 and verticalangles to A from R and Q. a. DA Form 6-19 (figs. 84 and 85) is used for the computation of a three-point resection 239. DA Form 6-18 problem. a. DA Form 6-18 (figs. 87 and 88) is used forb. Entries required are the coordinates of the computation of a two-point resection probpoints A, B, and C and the horizontal angles lem. If only the coordinates of point R areand vertical angle measured at point P. desired, the section labeled TO LOCATE STA c. The formulas to be used are shown on the TION Q (lines 36 through 40) is not used. If back of the form. only the location of point Q is desired, the section labeled TO LOCATE STATION R (lines41 through 45) is not used. 238. Two-Point Resection b. Entries required are the coordinates ofTwo-point resection is a method of survey points A and B and the horizontal and verticalsimilar to three-point resection. In two-point angles at points R and Q. resection, control is obtained from two visibleknown points. In figure 86, points A and B c. The formulas to be used are shown on theare inaccessible points of known survey conback of the form.trol. Points R and Q are points from which theother three points are visible. The solution of 240. Limitations and Use of Resectionthis scheme is the same as that of a quadri As a general rule, a point located by resectionlateral except that the angles at points A and (two-or three-point) should not be used as aB are not measured. As with three-point repoint from which to extend survey controlsection, certain preliminary operations must unless the location is checked by some otherbe performed. A map reconnaissance is remeans of survey. However, two-point or threequired to insure that all interior angles are at point resection can be used to locate a batteryleast 400 mils (221f2 °) and preferably greater center or to establish the 01-02 target areathan 533 mils (30°). Also, points A and B base of a field artillery battalion. If knownmust be visible from R and Q, and R and Q must points are available, resection probably wouldbe intervisible. Fieldwork consists of measurbe more rapid than the traverse method andwould allow the unit to conduct unobserved firemuch sooner. If necessary, corrections can bemade later by traversing to a known point. Inaddition, resection may be used to locate anysingle point, to check a location determined bysome other means of survey, or to verify pointsof suspended known control. 241. Resection Field Notes Resection field notes are similar to field notesfor triangulation, except that the height oftarget (known or estimated) and the height ofinstrument (measured to the nearest 0.1meter) are also recorded in the REMARKSFigure 86. Two-point r esection. section. AGO 10005A 151 -"'w > 8 g.... c:> "'> 1 ' OBSE RVED ANG L E 0 1 5 IS Sl! COMPUTATIOI'I· COORDII'IATES At-10 HEIGHT FROM TWO -POll-IT RESECTION (TM 6 -200) ' OBSERVED AHGL! R2 'I 331t.BI 21 AP-IGLE HAVING LOG TAN {20) 7 02. 3.2. A:! PEAT (10) l { 1 ) -+ {2) II/-~'f 19Z 8 9S' h2 ll A REPEAT(29 ) 0R (21l, ANGLE • OBSERVED ANGLE R1 / .2 oS '1-JI ;~·· .,~.,~?IB {... } 8_ ()O 00 " B2 "' 3'1 5.3 l2ll-aoo"' 93 1.2. " IJJl+U•l 13 Jf/ 35 ~ 32 ()() 01)() ~' \2sd'' ~ ~ ~ I I I " TO LOCATE STATION Q LOG TAN (22) I 9¥7 32.1/'1 • {l) +t • l (ENTER ON THIS LINE) .21. s~ b:L?> I ' " 8 ~ LOG GRID DISTANCE A TO 8 LOG TAN (II) !FRO M AUX COMP ON REV) -(S):::: ANGLE A2 ' ( 23 1 + 12 • 1 LOG Slf( ( 3S ) q ~ '115 :qoos~ {"''3200 ,ft,} .S 4S 377 ,. 9 .9.35 1(.1.76 " 3! J179 S/,16 .~ 7 OBSERVED ANGLE 02 /() '1-1 1/'U " S ! I:LZ. 7"1:L5 "I (36)+(37) ' REPEAT (11 ) 3! 1/~:.5: 1(.70~ ltE P UT ()) I R a " 7 .2'1 /,() " 1¥ "'"' 1"1;1. AI'IGLE HAVII'IG LOG TAI'I (25) REPEAT (1 3) 'I !i:i32 '16J3'1-I J2. oo_poD " iS 01 " (31 ) (39 1= '17 66'1 'I!Yo3 51:.1 / (26}-(27) (p .39 5.3 " A TO 0 3 ~ .532. 5or..b I LOG GRID OISTAI'ICE • 171+11) (ENTER ON THIS Lli'IE) .,Zif. 16 LOG SIN (10) " (261+(27) TO LOCATE STATION R LOG SIN {1) LOG GRID DISTANCE A TO IIF(I9 ) 1S: UO)I:O. : AND 13•l1S. 10 u~~111 } -( 9 )• ANGLE 8 1 7 () 2. 311> 17 'I !1:.85',531:.2 " ¥ o9 t..1 3!1.}19 5{,16 II LOG SIN (ol ) (FRO"' AUX COMP ON REV) II 1 ' 2 OF (J ) 7 2'/-p% 19 !"'" 56,11 (2i) (29) " "'ORE THAN {1 5) LOG SIN (lol) LESS THAN (15) ( 2'1} (21 ) q~ 1(,3 : CJI.)J.? ( 16l +t171+tll l LOG SIN (6) 'I ~ 70 7 1'.'1.5 It "' ~'ISS "'-'ISl " (oi i)+{A2) lO REPEAT 121 1 OR (29 ). ANGl.E A I " LOG SUII t7l ., !'932. 91,3'/-., !s'lo :~.n'l S' 0'1 1. 7 " 3 !.:l_4LI SI:J.~ IF (19) IS : (20)1S: I ]I REPEAT ( 6 ) REPEAT 1111 LOG SIN 12) "'ORE THAI'I (lSI " "! !199 5SPO 9 :l/-.SS /,/,1/~ S 'IS 38 .. 1~ 9h'-Sl-71 (19)-( 15 ) " LESS THAN 115 ) (IS)-119) l oll ) (ol ..l= (30)+1311 13 5.5o.S LOG GRID OISTAI'ICE A TO R 3. ~S'I 94 5 1 02Hilll+IU) " 9 ! S"' AUXILIARY COMPUTATION AZIMUTH AND DISTANCE FROM A TO B ST ATION E COORDII2~1/- LOG idE-LOG SIN BEARING = 3'. JI.1'1 5b'15 ~COSBEARING = ! ~ Enter correction(s) for curvature and refraction in block(s) matked * *· LOG GRID DISTANCE A TO 8 STANCE A TO B LJM!l'AT!ONS:(EHTER L OG GRID DISTANCE A TO B IN (36) AND/ OR (41) ON FRONT) Angles A1, ~· 81, ~· 01, ~. R1, and ~should be greater than 22 1/2° (400 n\) oraccuracy may fall ~low spec ificat ions RESULTS: Coordinates and height(s) of S!ation(s) 0 . or (and) R.TABLE -CCRRE=rtON FOR a.JRVATlJR[ AND REFRACTION Azimuth(s) from na~ion(s) 0 or (and) R to nation A. (NO INTERPOLATIOS NECESSARY FOR ARTILLERY St.AtVEY) FORMUL AS: (SIGN ALWAYS MINUS) At+~= 01 + ~Lo g Side: (M) C:m(M) Log Side (M) Tan z = Sin ~Sin 0 2 Sin~ Sin 81 Sin 0 1 Sin R1 Co"(M) Tan 2. = 3.019 .I 3.112 1.8 Sin 81 Sin 0 1 Sin R1 or Sin ~Sin 0 2 Sin ~ 3.230 .2 3.136 2.0 3.322 .3 3.184 2.5 Tan •;(A1 -~) = Tan ~(A1 + ~) Tan(Z-45") Tan !\(~-A1) =Tan '>(A1 + ~) Tan(2.-45") 3.386 . 4 3.824 3,01.435 ,5 3.857 1. 473 .6 3.5 3.886 1.508 .7 4.0 A8 Sin (81 + SV 3. 912 4,5 AO = Sin ~1. r,37 .8 3.934 5.0 1 .562 .9 3.955 5.53 .')S4 1,0 3.974 A8Sin lloz;! .tiZ5 6.0 1.2 3.992 6,5 AR = ~ ! . 65a 1.4 4.007 7,0 3. ~31 1,6 2. = a n auxiliary angle required onl y in the computations (always .between45 and 90 degrees) . U, S, OOYIRMWCI"T PRDITIMO OPPICI : ltst 0 • UOJU Figure 88. B ack of DA Form 6-18. "'c.. CHAPTER 10 TRILATERATION influence the probable error of the measured 242. General distance.Trilateration is a method of survey in which b. Angular distortions resulting from dis the sides, rather than the angles, of a triangle tance errors.are measured in the field. The interior angles c. The quality of vertical control used to of the triangle are then computed from the reduce slope distances to horizontal distances. length of the sides. The availability of elec d. The requirement to use quadrilateraltronic distance-measuring devices makes the use of this method feasible in artillery surveys. figures. Taping the distances would be uneconomical e. A minimum permissible interior angle of because of the manpower and time involved. 400 mils. f. The requirement to obtain direction from another source. 243. Employment Since the range capability of electronic 245. Computationsdistance-measuring devices exceeds the optical DA form 6-7a is used for the computation ofrange of issued theodolites and Tellurometers, angles from measured distances (fig. 89). Thetrilateration can be used in survey operations angles are then used in conjunction with theinvolving long distances. Trilateration can also side lengths to extend coordinate control, pro be used in operations involving shorter disvided a known direction is available. Height istances, when poor visibility restricts lines of determined by altimetry (ch. 11). The sidesight. lengths used on DA Form 6-7a can be UTM grid or sea level distances. If sea level distances 244. Limitations are used, they must be converted to UTM grid distances, by use of the log scale factor, when Trilateration measurements and computa the coordinates are computed on DA Form 6-2. tions are affected by-Complete specifications for trilateration are a. Unstable atmospheric conditions which tabulated in appendix II. I I I I AGO 10005A 154 l COMPUTATION-PLANE TRIANGLE (Using Three Sides) (FM 6-2) REWIRED DATA 1SKETCH:UTM oriel or sea level diStances of sides ( o,b and c. A OPTIONAL DATA if•Plooe UTM orid az imuth line o, b, or c. KNOWN AZIMUTH c TO ---+---~1 Ptone UTM gri d coordinates c s , 8 station A, B,or C. KNOWN COORDINATES 1 C~s;£;,_____.....,.______...;.r.:.,~ 8 S to , __ E I I I Q. N 1 KNOWN LENGTH o = NOTE : Always use a as lon gest known sode. 2 KNOWN LENGTH b 19 (Il l 3 KNOWN LENGTH c 20 LOG SIN (18) = '!tCf77~3187 4 (1)+(2)+(3) -2.1J. :J. I 07185 21 5 foF (4l 2 2 LOG (I) 6 (I) 2'3 (21) -(22) 7 (5)-(6) 24 ANGLE HAVING LOG SIN (2'3)= r1 8 LOG (7) 25 (13 ) =3! 9.52,'1b33 9 LOG (5) 26 (20) I 0 (8)+(9) 27 (25l+ (26) -3 r930~l820 II LOG (2) 28 (22) -3 1 78 S r11J.5' 12 (10)-(II) (27)-(28) =3:710 :1313 29 13 LOG ('3) 30 ANGLE HAVING LOG SIN (2 9)=51 14 (12)-(13) PARTIAL PROOF 15 10,000 0000+{14) -19 ,,, 1 :a1ito 31 12,' 13:u (' 8 > t6 toF (15l 32 (24) 17 ANGLE HAVING LOG COS ( 16) = '33 (30) 18 2 X ( 17)=q1 32., oo 1o1 REMARK COMPUTER I CHECKER IDATE P!=C GEROLD .SGT KANDRA 2,7 JUL jCf- REPLACES EDITION OF 1 OCT &2, WHICH IS OBSOLETE, Figm·e 89. Solution of trilateration problem, fourth-order survey, on DA Form 6-7a. AGO lOOOSA 155 4 CHAPTER 11 ALTIMETRY Section I. GENERAL atmosphere which is commonly accepted by the 246. General Army, Navy, and Air Force as having standard a. The 4,500-meter surveying altimeter is values. The standard conditions for altimetry used in artillery survey to determine the as it is used by the artillery are as follows: heights of stations that are not optically inter (1) Instrument temperature-75° F. visible and heights that cannot be determined (2) Air temperature-50° F.by trigonometric methods. The introduction of (3) Relative humidity-100 percent.electronic distance-measuring equipment into (4) Latitude-45° N (S). artillery survey has provided the capability of (5) Altitude-+450 meters. measuring distances between points lacking (6) Gravity acceleration---32.2 feet per intervisibility. This capability makes it possecond. sible for the artillery to use the trilateration (7) Wind-0 MPH. method of survey in extending survey control. Use of the electronic distance-measuring equipment in conjunction with trilateration places 247. Surveying Altimeter added importance on the use of the altimeter. a. The altimeter issued to artillery units (fig. 90) is the altimeter, surveying, 4,500-meter, b. The basic principle of altimetry is that 2-meter divisions; it is normally issued andthe pressure caused by the weight of the used in conjunction with the Tellurometer or column of air above the observer decreases as DME. the observer rises in altitude. If weather conditions and instrument conditions were always b. The surveying altimeter is an aneroid standard and never varied, it would be possible barometer which measures atmospheric presto set up a pressure-altitude ratio that would sure by mechanical means. The scales are so enable an observer to measure the pressure at graduated that air pressure is indicated in any given point and then rapidly compute the units of height (meters). Under standard conaltitude (height) of that point. In altimetry ditions, it has a range from 300 meters below to this is essentially what takes place; however, 4,500 meters above sea level. The instrument because weather conditions, instruments, and contains an aneroid element consisting of a geological and geographical conditions vary single vacuum chamber. Expansion or contracwidely and because air varies in density, it is tion of this chamber is indicated by the rotation not possible to set up a pressure-altitude ratio of an indicating hand and the movement of a which by itself will always produce an accurate revolution indicator. result. It is therefore necessary to establish a set of standard conditions to use as a basis for c. The altimeter has a circular dial with four scales; two scales are outside the circular the pressure-altitude ratio. Variations from the standard conditions are converted to correc(annular) mirror, and two scales are inside tions and applied as required to compensate for the mirror (fig. 91). The indicating hand their effect. The standard conditions for makes nearly four revolutions in measuring altimetry are based on the International Civil throughout the range of the altimeter. A Aeronautics Organization (ICAO) standard revolution indicator designates which scale AGO 10005A 156 INSTRUMENTTEMPERATURECORRECTION SPANNER WRENCKCHART •FOR SCREW PLUGS SLINGPSYCHROMETER EXTRA BULBS LIGHT DIFFUSOR RHEOSTATAND SWITCH LAMP SCREW PLUG Figure 90. Surveying altim eter, 4,500-meter, 2-meter divisions. should be read. Zero on the dial corresponds to become equal to that outside. The case can be a pressure-height of 300 meters below mean sea made completely airtight by shifting a movablelevel under standard conditions; 4,800 on the vent cap to the closed position and closing thedial corresponds to 4,500 meters above mean lid. The vent normally is left open; however, itsea level under standard conditions. The least should be closed when the instrument is packedreading on the scales is 2 meters. Each altimfor shipping. A built-in night lighting systemeter dial is custom calibrated for the vacuum uses standard flashlight batteries and lamps. chamber and mechanical linkage with which Scale lighting is controlled by a switch and it is to be used. For this reason, the dial, the rheostat assembly. Batteries should be placed in vacuum chamber, all parts of the mechanical the case only for night operations. A silica gel linkage, and the instrument temperature cordesiccant is in a container in the lower part ofrection chart are not interchangeable with the case. A reading glass, a folding sling psy corresponding parts of other altimeters. In chrometer, a spanner wrench, calibrationthe face of the dial is a desiccant condition incharts, correction tables, and spare parts aredicator which becomes pink when moisture stored in the lid of the case.within the case is excessive. d. The case is airtight except for a small vent 248. Sling Psychrometerwhich permits the pressure inside the case to a. The sling psychrometer provides the wet AGO lOOOSA 157 L_____________________________ ~I Figure .91. Altimeter dial. against a standard thermometer or against bulb and dry bulb temperatures that are used each other. When this check is made, the wet to obtain the correction factor for air temperature and relative humidity. The psychrobulb reading must be made with a dry wick. A meter consists of two identical Fahrenheit correction factor should be determined for a thermometer that does not agree within 2° of thermometers (the bulb of one thermometer the standard thermometer. If the thermometers is covered by a cloth wick) suspended from a are checked against each other and a differencebar and enclosed in metal sheaths to prevent of more than 2° exists, a correction factor breakage. Psychrometer readings are made as should be determined for the wet bulb thermo follows: Unfold the psychrometer and saturate meter and recorded in the instrument case. the wick of the wet bulb thermometer with clean water. Holding the handle of the ps.ychroThis correction factor will be applied to all field data determined by the psychrometer. meter in one hand with the link and thermo meter assembly at a right angle to the handle, 249. Weather Conditions rotate the psychrometer two or more revolutions per second for at least 1 minute. ImThe accuracy of heights determined by altimmediately read and record the temperatures of etric leveling depends on the stability of preboth thermometers, first the wet bulb temperavailing weather conditions. Valid results canture and then the dry bulb temperature. (If not be obtained during periods of strong or the air temperature is below 32° F, only a dry gusty winds or during thunderstorms or other bulb reading is taken and the correction factor turbulent weather conditions. In general, the is determined from this reading.) best results are obtained when windspeeds are less than 10 miles per hour. When wind b. The thermometers should be checked AGO 10005A 158 velocities exceed 15 miles per hour, altimetry b. Artillery personnel are not authorized toshould not be relied on as a method of deterrepair the instrument. They should never remining height. Generally weather conditions move the window. The spare indicator handare most unstable from 1000 to 1400 hours, and which is issued with the instrument should be.an altimeter reading should not be made during replaced by engineer instrument repair perthese hours if it can be avoided. The atmosson el if replacement is necessary. pheric conditions that prevail during fog, mist, or light rain are usually suitable for altimetric c. Artillery survey personnel are authorized leveling. The altimeter should be shaded from to remove and dry or replace the silica geldesiccant in the instrument when the desiccant the direct rays of the sun when readings arebeing taken. condition indicator turns pink. The silica gelcan be dried by heating it at 300° F for atleast 10 minutes. 250. Care and Maintenance of the Altimeter a. Although the surveying altimeter is a d. Artillery survey personnel are authorizedto replace the lamp bulbs for the night light delicate instrument, it is rugged enough to be ing system and to insert and remove the bat used for field survey if handled properly and teries for the system. The batteries should not protected from shock. The instrument and itsaccessories should be kept clean and dry. The be inserted until the instrument is to be used window of the instrument is made of clear at night, and they should be removed when the night work is completed. plastic, which scratches easily. It should be brushed with a camel's-hair brush to remove e. Artillery survey personnel are authorizeddust and polished with lens tissue or a soft to replace a broken thermometer in the slingrag. The window should be waxed periodically. psychrometer. A thermometer can be replacedThe instrument should not be oiled. Oil will by removing the screwcap from the end of theinterfere with the operation of the instrument psychrometer head. The cork disc for the cap and cause erroneous readings. must be in place when the cap is replaced. Section II. USE OF THE ALTIMETER 251. Methods of Altimetry simultaneous scale readings, corrected and ad a. Two methods of altimetry are employed in justed for instrumental differences, are comartillery survey. These methods are-pared to determine the differences in heightbetween the base station and the field sta (1) The leapfrog method (para 258) tion (s). The wet and dry bulb temperatures,which is of primary interest to the made at the base station at the time of theartillery since this method is partic simultaneous readings, are used as argumentsularly suited for use in conjunction to determine the correction factor from the airwith Tellurometer or DME systems. temperature and relative humidity correction(2) The single-base method (para 261) chart (fig. 92). This correction is applied towhich is of secondary interest to the the difference in the adjusted scale readings to artillery but may be used in special obtain the corrected difference in height be situations. tween stations. b. Both methods of altimetry employ a base d. The field station and base station make station and field stations. A base station is a simultaneous readings by coordinating the timestation or point of known height; a field station by radio communication or by using a pre is a station for which the height is to be deterarranged observing schedule. Consequently, themined. watch of the field station observer must besynchronized with the watch of the base stationc. Both methods of altimetry require simul observer. taneous readings of the altimeter scales at thebase station and at the field station (s). These e. During normal weather conditions, a AGO 10005A 159 ill!&....! AIR TEMPERATlJRE 6o RELATIVE HUMIDIT'l CORRECTION FACTOR FOR ALTITI!DE Wet Bulb Temperature De Rrees P . Temperature Below Freezing 32 34 35 38 40 42 44 46 48 50 52 54 56 58 60 62 ""' •• IDes. P. Factor 32 0.967 32 -•> 0.772 34 0.971 0.971 This chart is to be uaed to obtai" the ~temperature and relative humidity cor-,..2!_ -60 0.782 36 0.974 0.975 0 975 rectiona required when using the single 38 -5} 0.792 38 0.978 0 . 978 0.979 0.979 base method of altimeter leveling. Uae ,___ only with altimeters aet and calibrated ~ -50 0.802 40 0.982 0.982 0.983 0.983 0.984 in meters according to the Smitheoniao -4} 0.812 42 0 . 985 0.986 0.986 0.987 0 . 987 0.988 Meteorological Table No. 51. ....!tL -40 0.822 44 0.989 0.989 0.990 0.990 0.991 0.991 0 . 992 ,_.!!L -38 0.826 46 0 . 992 0.993 0.993 0. 994 0 . 995 0.995 0 . 996 0 . 99 r-!!L48-36 0.830 48 0.996 0.997 0.997 0.998 0.998 0.999 0.999 1.00( 1.000 I--50 -34 0.834 50 1.000 1.000 1.001 1.001 1.002 1.002 1.003 1.00 1.004 1.005 52 -32 0.838 52 1.003 1.004 1.004 1.005 1.005 1.006 1.006 1.007 1.008lt. 008 I t o09 54 -30 0.842 54 1.007 1 . 008 1.008 1.008 1.009 1.010 t . OtO 1.011lt.Oll . 01 .01 .01' 56 -28 0.846 56 1.011 1.011 1.012 1.012 1. 0 13 1.013 1 . 014 1. 0 14 1.015 1.016 1.016 1.017 1.017 -26 0.850 58 1.014 1.015 1.015 lt. 016 1.017 lt. 017 lt.ot8lt.018 .019 .01 .020 .020 . 0?1 0 ?' 58 60 .0?. o?< 0" -24 0 . 854 60 1.018 1.019 1.019 1.020 1.020 1.021 1.021 1.022 .022 1.023 1.024 1 024 62-22 o. 858 62 1.022 1.022 1.023 1.023 1.024 1.024 1.025 1.025 1.026 .027 on 028It 0' " 0 ?0 "'" "" 64-20 0.862 64 1.026 1.026 1.027 1.027 1.027 1.028 1. 0 28 1. 029 1.030 1.030 1.031 1. 032 1.032 1.033 1.034 1. 034 lt.035 66 -18 0 . 866 66 1.030 1.030 1.031 1.031 1.032 1.032 1.033 1.033 1.034 1.034 1.035 1.036 1.037 1.037 1. 038 I t.039 lt. 040 68 -16 0.870 ,.;68 1.033 1.034 1.034 1.035 1.035 1.036 1.036 1.037 1.038 1.038 1.039 1.040 1.040 1.041 1. 042 1.041 1.043 1.037 1. 038 1.038 1.039 1. 039 1.040 1. 04t 1. 04t 1.042 1.043 1.043 1.044 1. 045 It 0!+6 lt .046 1.047 70 ~ -14 0.874 : 70 • 04 n.t.o n1717GLTI<:OW (SEE PAl{!/ I 7i') (. CoRR. FeTEJJ "Ill£ Q, 1:4"/N'r. iflLG£81?~/C Sf!.'MilLCtJ .t/A/AIS ~ 7 DRY 'r?IJJ.R n ~M.o~n '"r (SlIE ?AI?//_ I J'O) If Wf.T t?ULB 7. IMPERA1 VR~ rs ·~; f'Alli}_ li'IJ) Ia 5~P'" Figure 94. Altim et e1· A recorder's notes for altimetry (leapfrog). (4) +0.07 meter (correction per degree) field notebook located at each station (figs. 94(from correction chart, fig. 93). and 95). In addition, for comparison purposes, (5) 25 ° x 0.07=1.75 meters (correction the corrected scale readings for both the baseto be applied). station and the field station are recorded inthe field station field notebook (fig. 96). (6) 2431.5 -( + 1.8) = 2429.7 (correctedscale reading) . -b. After the field survey is completed, thefinal comparison is made and recorded in the 255. Comparison Adjustment same manner as the initial comparison. a. The base station instrument is placed at a c. The time lapse between the initial comstation of known height. The field station altiparison and the final comparison should bemeter is placed beside the base station instruhela to a minimum, less than 4 hours ifment at the same height. The initial comparison possible. is made by taking simultaneous readings of the d. If the initial comparison agrees with thetwo altimeters and recording in the field notefinal comparison, then the comparison adjustbook (DA Form 5-72, Level, Transit and Genment is considered standard for all altimetereral Survey Record) the time, instrument temreadings taken in between. If the initial andperature, and scale reading for each. The data final comparisons do not agree, then a com for each station instrument is recorded in a parison adjustment graph must be constructed AGO 10005A 16 3 L..__ _ _________ _ __ -------- 37 WEATHER : CLEAfl\ WARM CHIEF Of f'AISIY Bli'oWN B IJl7tMETER. DATE .2. IJ/1_(2 19 INSTIWM£NT;:#: 77/S OBSERVER· KUTCUALL DESI GNATION ALTIME.1RY LEAPFROG-IHSr. SC:A~E IJYSr c"'"'.':'c.rs-.IJ OMflllf/SON l "'o;~:r~o /i'EMA I'KsSTI/r/11/Y rtHE rrMP. ,f'E.f0/1116 lilif'r_, Ri;~~~c; DJVS7MCNT IR'EJ.'i> Ali<. ISOS" 71 7//). () +tJ.S" 7/LI · 5 IJ~BtlcKL~ IV Sc.P-I 1!130 82. 7o]. .o +-o . (, 1~2 . 1.. + /. 3 7H. 9 703.1 -+ /. I 7tJ'!-.1. 8JJ sc .P-I /SSO f2.. 1D2.S + () ." ,'11.'1 911 scf'..3 II.. SO f'/-f.. 'II. 0 + o.7 lo'll. 1 + tJ. 2. -/) . it !,'/(). (, BJ/ scP-3 17.Jo 17 "9/. 0 + /. 0 f..'f/.0 aROB£!? 17SS f7 7'10· 0 _+_1 .0 fl/. 0 I :z. 3 '/ s 7 ~ " WEAD!AIG IS'T'A.t'.'&'AI C11LV.HN I SrAT/11 VATWKI•fK ••BN/U. 1.2. riME 'F LU1S~ R1LA_T_/~Jl 1.3 INST~ 11111~11/T_j t£:Mf1_EJ{A_ tJduL 4/ "8" A _S_C~ 0q$JII/). 'rnu1c '{.SEE.PARAL22)S /NS71if/JM_Eh'I_ r£M. ro _C t>li'JII E : T;:n _<;t" lA. E t;'E, •JJ, II& A. -~ERNAJc SuMo•F t'oLI/~-.1/~ .1.1 AAI/),S"' 1 r,..,.p_. 'R,~o.N_ ln. •o_· I'L'tJ ~/ 7f.l. r AJ>_,;_us t.fD_ :SeAL flEADINI ALG£8, Btc. :ii.!M oF CoL. IJNIN5 t..AND7 ;;. 7~ 0 Figure 95. Altim eter B rec01·der's notes for altimetry (leapfrog). t o determine the adjustment for intermediate ence in the corrected scale readings to stations (fig. 96). The procedures for preparplot the final comparison point on the ing and using the graph are as follows: graph. (1) Set up the graph by assigning time (5) Join the two points with a straight values to the vertical lines in the field line. station field book, to include the ob(6) Using the watch time for each interserving period from initial to final mediate station occupied by the field comparisons. station instrument as the argument, read the comparison adjustment for (2) Assign "difference in corrected scale reading" values to the horizontal that station from the left side of the lines, to include the difference begraph. tween the initial and final com(7) Then, enter the comparison adjustparisons. ment in the appropriate column of (3 ) Use initial watch time and the differthe field station field notebook ence in the corrected scale readings (opposite the time observed) and to plot the initial comparison point apply the comparison adjustment on the graph. algebraically to the corrected scale (4) Use final watch time and the differ-reading to determine the adjusted AGO 100 05A 164 38 b. If the wet and dry bulb temperatures. are COMPARISOt.l ADJUSTNfNT ~RAPH (LfAI'rROG) known, the correction factor can be determinedfrom table I, Air Temperature and Relative (Dftf/ECTED CDiff/ECTEO STAT/ON TIME I J?f!~,•.fr. .STAT ION TIM£ l lli~~~!r.. Humidit y Correction Factor for Altitude (fig."A "AR8UcKU ISDS 112..2. GRUBER . 17SS 190.3 92 ), one of the tables in the lid of the altimeter.·a"AI?KutiiH. ISO!!i 110. 5 .GRU8ER / 7SS 71/. 0 The chart is entered at the top with t he wet + /. 7 -/) . 7 bulb temperature and on the left side with thedry bulb temperature. The intersection of the WATCJI "!ME two columns is the correction factor. This cor1S klo ,, /l DO IR 1,, rection factor is applied by multiplying it by.."' ./'"INJT/J L DO CDMPifR SD/11 DIFFI :RENe E the difference between the corrected scale read t:n 1'\ ,..( 1Pti81S~AI /JJVSTffiEio Folf'a!ftJ Elf-ing of the base station altimeter and the IIN.scP-1 + t-~ I 1C '1( adjusted scale reading of the field station altim '\.. COM PAll f/JIII AD.JV T/ll&lfr 4R eter. The correction factor should be inter1'\ SN St:P--8,YJcp. • +1. 1 "~ .. polated to the nearest thousandth in table I. " · en " .c '\. t'iliiPAIIS N 1//)JLHT, osliiiiCiltl I UdcTMI'NT by Altimetry,. en 1\.'!~ 8/IS COMPUTE R /3L O)( O M 3 AOG ICJ :;') KEOIHAN [:; 1 a. "r : c.r ~; ·s ·01so~r. ·• 0 0 0 -0 DA , ~~~"'" 6-2 7 "' > F igu1·e 98. Computations, DA Fonn 6-27. -----------------------IlL-------------- -~~ I ~-~ GIVEN RESULTSI t=uR S~CLE-BASE METHOD: For each rtetd station. altimeter scale reading at base su.tion aud ct.djnstcd scale reading at field n afion (~ken at same time): dry bulb temperature and wet bulb FOR SINGLE-BASE METHOD: It can be expected that heights determined will have a maximum temperatl.l'e .u ba se s~tion and field st.a tion (temperature at base station interpolated to time of a.::"dings at field s~tlon): height of base station. made as prescribed. error of 4 meters and an a vaage error of 1 1/2 meter when observations wing standard equipment are FOR LEAPFRCXi METHOD: FOR LEAPFRcx; METHOD: For each leg: altimeter scale reading at base station and adjusted It can be expected that heights determined will have a maximumscale reading at first field sta tion (taken at same lime); dry bulb temperature and wet bulb temper..error of 2 meters and an average error of 1/2 meter when o bservations using standarc! equipment are made as prescribed, ature a t base station and first field station (taken at same :ime); height of base station. Adjusted icale reading at flrst field station (base Harton for second half of leg) and altimeta scale reading Jt second field station (taken at ~me time)t dry bulb tcmperawre and wet bulh temperature at hrst and second field ~tatioru (tak~n at same time). FORMULA GUIDE D C(B -A) • ~A base station adjusted scale readingB field station adjusted scale readingFOR LEAPFRcx::; tviETt-100: Height of base station for each field station except t he first field c height correction factorstation is height computed for previous field stauon. D height of field station E known height of base stationFOR BOTH METHODS: Use known heights w narest one-tenth meter . Convert known heightto metels when given 10 feet or yards. Use logarithms to fi ve places. When known height of base station in step (1 6) 1s below $ea level. use step (16) as a negative value and proceed wilh computa tion . Refer to TM 6·200 for additiona l information. HEIGHT CONVERSION-BASE STATION LOG OF HEIGHT I 3 I LOG CONVERSION HCTOR -~I ( 2)+(3 ) I I" ! s INU,.BER HAVING LOG (. )= HEIGHT IN "'ETERS -~ ~~--~-~~+-~~~~------ I ~ GP086 15 9A Figure 99. DA Form 6-27, reverse side. comparison readings are made at the base sta•tion, the altimeter A recorder remains in posi- SEQUENCE OF OBSERVATION tion at the base station and makes readings at ~ 19 ~DATE DESIGNATION 5-minute intervals throughout the observing BHSCP-1 EJNSCP-2 BNSCF-3 GRV8Efl. period. After the initial comparison, the al ARBUCKLE timeter B recorder visits the field stations in A -1505 ~1/V/T IAl C~MJ;Jqg,s"AI ~lEAn •111,-_ sequence and makes simultaneous readings. 8-/SOS J After the readings have been made at the last A-1530 B-1530 field station, altimeter B is returned to the B-1550 A-1550 base station and a final comparison is made. 8-1{,50 A-,,so For economy of time and effort, more than one8-/730 A-11.30 field altimeter can be used in conjunction with .1"/.A/-' J. C1111fP.~RI.1•AIIi '€IfP/IIIG with no reduction in II-!755f the base altimeter 8-JZS5 ~¥ accuracy. b. The computation of heights of stations on DA Form 6-27 for the single-base method is ,.,.-r--.... the same as that for the leapfrog method except L::::. ;;. for one difference. In the single-base method, "A" }'-the known height of the base station (block 16) "B" L::::. 7'-. ~ / remains the same for the computation of-'-""" heights of all field stations, since the base station remains fixed throughout the observing I period. A sample of the sequence of observations is shown in figure 100. Sequence of observations, single-base Figure 100. method. 170 PART THREE DIRECTION DETERMINATION CHAPTER 12 ORIENTATION FOR ARTILLERY Section I. INTRODUCTION 262. General scheme. The uncorrected astt·onomic and gyro Orientation as used in artillery survey refers azimuths differ from the true azimuth by the to laying weapons and target-locating devices same amount. Azimuth gyrc.s currently in use with reference to a common direction, or by t he artillery depend on calibration against azimuth. Orientation is more important than anot her true azimuth, usually an astronomic azimuth. horizontal position because an azimuth error increases as the distance from its origin in creases. The artillery surveyor must furnish 264. Grid Azimuth weapons and target acquisition elements withgrid azimuths. However, he will be working Grid azimuth is an azimuth referenced togrid north. It differs f rom true azimuth by the with true, magnetic, and assumed azimuths as well. amount of the grid convergence. The gridconvergence must be computed and applied to atrue azimuth before it can be used by the 263. True Azimuth artillery. True azimuth is an azimuth referenced to true north as defined by the axis of rotation of the earth. Geodetic, laplace, astronomic, and 265. Magnetic Axi uth gyro azimuths are all treated as true azimuths Magnetic azimuth is an azimuth referencedby the artillery surveyor. Each of these to the local direction of the earth's magneticazimuths contains some error due to geodetic field. It is not accurate enough to place adjacent considerations. In some cases, the error, or artillery units or target acquisition devices ondifference, between these azimuths may exceed a common azimuth. It will vary throughout the 0.1 mil. Artillery surveyors are not required day by 4 to 6 mils. Magnetic storms will causeto take these errors into account. All of these large variations that cannot be predicted.azimuths depend basically on astronomic Local magnetic irre:5ularities will cause errorsazimuth. Geodetic azimuth is the most accurate that frequently exceed 20 mils. The primarybecause in general it represents an adjustment use of magnetic azimuth should be as a checkfrom a large number of astronomic azimuths. against gross survey errors. It may also be usedLaplace azimuth is the next most accurate. It as the assumed azimuth for a false grid. Whenrepresents a single astronomic azimuth which a magnetic false azimuth is used, units workhas been corrected for local deflection of the ing together should be tied together by a direcvertical, as determined by the geodetic survey tional traverse. Section II. SOURCES OF AZIMUTH 266. Geodetic Azimuth lished survey, the trig list for the area willGeodetic azimuth is obtained from existing show the geodetic azimuth to several pointslocal survey. In an area where there is an estab-for each station. It can be assumed that in a AGO 10005A . 171 ~I well-surveyed area the established points have 270. Determination of Grid Convergence been adjusted to each other so that the azimuth True azimuths must be converted to gridcomputed between two intervisible points will azimuths. The computations for grid conver be a good geodetic azimuth of the same order gence are performed on DA Form 6--20 (figs.as the original survey. In general, a more 101 and 102.) This form was originally deaccurate azimuth will result if the points signed for use in converting astronomic azichosen for the computation are some distance muth to grid azimuth. It can easily be adaptedapart. Geodetic azimuth may be given by for use in computing convergence for gyro orhigher headquarters as part of the starting geodetic azimuth. The left-hand side of the data. form is used for the computations if geographic coordinates are used. The right-hand side of 267. Azimuth From Coordinates the form is used for the computations if UTM coordinates are used. If both geographic and A starting azimuth may be obtained by comUTM coordinates are available, the computaputations between points established by U.S. tions should be made on both sides of the formArmy surveyors. Caution must be used when and no further check on the computations iscomputing between points recently established, required. If the computations are made on onesince, in general, they will not have been adside of the form only, independent computajusted and will not have a proper relationship tions must be made by another computer toto each other. Azimuth computations from cofurnish a check. The instructions on the formordinates of first-, second-, or third-order sur suffice. veys will generally yield a comparable degree of accuracy, whereas computations from coordinates of fourth-or fifth-order surveys can271. Grid Azimuth From UTM Maps not be assumed to yield an acceptable accuracy. A grid azimuth can be obtained from a mapFourth-order surveys will yield an acceptable by selecting an instrument station and twoaccuracy, provided the azimuth has been adorienting points which can be accurately scaledjusted. In fifth-order surveys, use should be from the map. A line is drawn on the mapmade of the azimuth being carried through the through each orienting point and the instruscheme rather than relying on computations. ment station. The grid azimuth of each line is then scaled from the map. The orienting points 268. Directional Traverse should be so located that the difference in the azimuth of the points is as near 1,600 mils as Directional traverse is used to carry an azimuth from a source to an orienting line. The practicable and the distance to each point from the instrument station is near 5 kilometers. An method used is the same as that used for posierror of 25 meters in either point will create antion traverse except that the measured distance error of 5 mils in azimuth at 5 kilometers. Thebetween stations is not required and, in gentwo orienting points should be near 1,600 milseral, longer lines of sight may be used. See apart in azimuth to give a check on both thechapter 8 for instructions for turning angles map and the map scaling. An angle-measuring and carrying azimuth through a traverse. instrument is set up over the selected instrument station in accordance with instructions 269. Astronomic and Gyro Azimuths in chapter 7. The angle between the two orientThe method of obtaining an astronomic ing point s is measured and compared with the azimuth is explained in chapter 13. The method difference between the scaled azimuths. If the of obtaining a gyro azimuth is explained in difference between the scaled azimuths and the chapter 14. Both types of azimuths are treated measured angle is greater than 10 mils, another as true azimuth and must be corrected for grid orienting point must be selected and the process convergence before use. In general, determinarepeated. If the two values now agree within 10 mils, they may be used as the grid azimuths. tion of astronomic or gyro azimuth is made on one end of the line requiring azimuth so that If the difference between the values still exceeds 10 mils, a new instrument station must directional traverse will not be required. AGO 10005A 172 COMPUTATION. CONVERGENCE (ASTRONOMIC AZIMUTH TO UTM GRID AZIMUTH) TABLE HUMBER$ REFER TO TM 6-300-19...1e.... STATION AZIMUTH MARK BVI sc.P 'SI~i\ON OF\'t<.. LONGITUDE OF STATION II G1 UTM GRID II 1~51 3'2. ZONE fASTING Of STATK»H I I ~ 33 1~DO NORTHING OF STATION un'""'""""~ • ~ ~ 331. 1 '~'~" ,,. :.. ::'""'""""~ (,~3 1 /;00 LOHGITUDE OF CENTRAL MERIDIAN 2 12 1}•:}}•• (FROM TABLE OH REVERSE) II 1/.0100 .500000 IF (1) 15< (l) IS, MORE THAN (2) (1)-(2) 17 3:5'132. IF (It) IS1 (13) IS1 133 (,00 MORE THAN (12) (11)-(12) l LESS THAN (2) (2)-(1) 13 LESS THAN (12) (12)-(11) 24_1(,8 !33 ~~ • ~~~~~~~Nn~E~_RE_E~U~~~~k~; REPEAT (13) WITH DECIMAL IF 111 ; IHMii-s. REPEAT 111 2'1~&.8 ,. 1 0 PO ifoi T MOVED LEFT SIX PLACES 133 j(p_Qf!__s LOG l•l LOG(U) 1 1 3~2.~ 3~~ 1S .<~. 1 125 80/o 6 LOG SIN LATITUDE OF STATION l9 1 7oZ 51Jl/ 16 LOG OF FUNCTION r;j ~ 874) IH&LE 61 'JS: iz7fi1 8141/ 7 {5) +(6) (IS) +(16) 111 o"" n~ 17 3~~01 ~70 HUMBER HAVING LOG (7)-= I LOG CONVERSION FIRST TERW. IN SECONDS OR MILS SECONDS TO MILS IZ ~44 II 71693:575 SECOND TERM (TABLE 8 OR 9 8-II&ILS. USE {l) AHO LATITUDE) oo 19 IF (nISIN DEGREES. REPEAT (17) o 1 IF (1) IS IH ..ILS, USE (17)+(11) I ~ O'IS I 2'/5' (ll+(f)• COMVI!RGEHCf IH SECONDS Olt Mtl.S I 20 HUMBER HAVING LOG (19} = FIRST TERM IN SECONDS OR MILS II'HEH ST ATIOM IS IH HOitTH LATITUDE .u4D . _ I J:Z. ~.tiS IH WUTLOHG IH EAST LOHG SECOND TERM(TABLE 7. USE If (I) IS. (10)ts. 21 MOitE ntAH (2) -+-.!.!!L!!:. I (rl) AHD HORTHIHCJ -0 ~00 LESS ntAH Ill -+ I I (lO) -UI)• CONVEitGEHCE IN SECOHOS Olt •HEN STATION IS IN 50UTH LATITUDE AHD•• MILS IM •t:ST LONG IM EAST LONG I WHEM H ATtON IS IH HOitTH LATITUDE I MOitE THAN (l) ~ ~ If IIIIlS. !!!!...!!! IP(1) IS. -+ ~AN(I]) I LESS THAN(!) + -I LI!SS lHAfll (1]) + '10 I wtt(H ST ATION IS IH SOUTH LATITUDE ~ I'Z. ~44 I lf(ll)IS, tnliS. + ~-·..···•·········•·· I I r .• \L ·•••··• : :r 22 :':~:::.~·~~~~· ~ 12. !11s IF (10) AHD (22) DIFFER BY MORE THAN { o•" }0.02 .c REDETERMINE COORDINATES AND RECOMPUTE All COMPUTATIONS ····························· } .·..... 3i r· l CONVERGENCE IF_(I) IS IN DEGREES.~~H~~S~F 1:'"':{ ··:··· \::::":>•.;.: rr It)f '''· •······ ;-; ii)i5'i~'!.:i.f.~~:.~~'c22i-~ IZ. .1/~ SUMMARY OF ASTRONOMIC AZIMUTHS AND COMP TATION OF UTM GRID AZIMUTH II ASTRONOMIC AZIMUTH REMARKSTO AZIMUTH MARK SET NR 1 I" J./0 :,'3 :8 I :25 SET HR 2 I I I 26 SET HR 3 I I l _l_ 127 SET HR I I I SET HR I I I Ill I SET HR 129 :33 8 SUM J/0 IJO Ill MEAN (SIGH+ ) I I I+J/o 13'31e + I I CONVERGENCE I 132 ~ I REPEAT (23) tl z. 1"' ! I I ALGEBRAIC SUM Of (31) AND (32) 133 I = GRID AZIMUTH TO MARK 4() 'Z./ 14 COMPUTER ICHECKERSM !TI-l :So~E.S ISHEET OF I SHEETS I =~::::~E 4-8-(p JAREA RouAJd f(,/1 OATE29 1'/IIY 19145 DA FORM 6·20 Figure 101. Entries on front of DA Form 6-20. AGO 10005A 173 TABLE -CENTRAL MERIDIAN OF UTM GRID ZONES MILS ZONE DEGREES IIIILS ZONE DEGREES MILS ZONE DEGREES MILS ZONE pEGREES LONG E LONG NR E LONG ENR W LONG W LONG NR W LONG W LONG NR E LONG 31 3 53,33 ~6 93 11153.331 177 3146.67 16 87 15~6. 67 81 ~~~0. 00 32 9 160,00 ~7 99 1760.002 171 30~0.00 17 1866,67266,67 ~8 1053 165 2933.33 18 75 1333. 33 33 IS 1973.33 3~ 21 373.33 ~9 111 ~ 159 2826.67 19 69 12?6.67 so 117 2080.00 s 153 2720.00 20 63 1120.00 35 27 480.00 2186.67 586.67 51 123 6 1~7 2613.33 21 57 1013. 33 36 33 2293.33 7 1~1 2506,67 22 51 906,67 37 39 693.33 52 129 38 ~5 800.00 53 135 2400.00135 2400,00 23 ~5 800,00 8 2506.67 9 129 2293.33 2~ 39 693.33 39 51 906.67 5~ 141 2613.33 1013,33 55 14710 123 2186.67 25 33 586.67 40 57 153 2720.00 480.00 ~1 63 1120.00 5611 117 2080,00 26 27 373. 33 ~2 69 1226.67 57 159 2826.67 12 111 1973.33 27 21 1333.33 58 165 2933. 33 13 105 1866.67 28 15 266.67 ~3 75 « 81 14~0.00 59 i71 3040.00 14 99 1760.00 29 9 160.00 53.33 ~s 87 1546.67 60 177 314~.67 15 93 1653.33 30 3 CONVERSION COMPUTATION SECONDS TO DEGREES, MINUTES, AND SECONDSDEGREES, MINUTES, AND SECONDS TO SECONDS . 'I " 9 REPEAT (22) OF COMPUTATION 1 REPEAT (3) 0 I ' 2 NUMBER OF DEGREES IN (I) I 10 ~NUT~BM ~~J~~~SR3g~D~IJ~~~~ IN (9 X60 11 REPEAT (9) 12 NUMBER IN (10) X 3600 3 (2) X 60 . 13 (11)-(12) ~ NUMBER OF MINUTES IN (1) NUMBER OF liMES 60 DIVIDES 5 (3)+ (4) I~ INTO (13): NUMBfR OF MINUTES IN (9 .. .., X60 15 REPEAT (13) 16 NUMBER IN (14) X 60 6 (5) X 60 " 17 (1S)-(16):NUMBER OF SECONDS IN (9) 7 NUMBER OF SECONDS IN (I) IS ~ko~;E~4lN"J~~J ~<.:FUR'"o~~Krt:r«.;t: 0 ' " 8 (6)+(7) ENTER IN (4) ON FRONT GIVEN: UTM grid zone of area of operation. UTM grid coordinates of station lO nearest meter. Latitude and longitude of station to nearest second or one-hundredth mil (DA Form 6-10, 6-10a, or 6-11).A value of astronomic azimuth for each set of ob~rvations (DA Form 6-10, 6-lOa, or 6-11). GUIDE: When using a mil-graduated instrument,- (1) through (5), (7) through (10), and (20) through (22) of computation are computed using a. hundredth-mil values. b. (6) and (24) through (33) of computation are computed using tenth-mil values. Compare (10) and (22) and, if they differ by more than 4 seconds or 0. 02 mils, redetermine coordinates and recompo·~ all computations. LIMITATIONS: This form should not be used when accuracies greater than third-order are required. RESULTS:A value of UTM grid azimuth from the mean values of astronomic azimuth and the grid convergence at the station. FORMULAS: UTM grid azimuth = Astronomic azimuth + convergence. USING UTM GRID COORDINATES: Convergence = (XV)q -(XVI)q3 (XV) = a variable function based on latitude of station (obtained from TM 6-300-19_, "Army Ephemeris for 19 "), ~ q = 0.000 001 times the distance meters from central meridian of UTM grid zone to station. (XV l)q3 = second term of convergence computation (obtained from TM 6-300-19_, "Arm-y Ephemeris for 19 '). USING GEOGRAPHIC COOR.iJINAT£5 : Convergence = (XIl)p + (XIIl)p3 (XII) = 10, 000 times sine of latitude of station, p = 0.0001 times distance in seconds or mils of arc from central meridian of UTM grid zone to station. (XIIl)p3 = second term of convergence computation (obtained from TM 6-300-19_, "Army Ephe meris for 19_ '}. DA FORM 6-20 Figure 102. Auxiliary computations and instructions on back of DA Form 6-20. AGO 10005A 174 be selected. Works of man, such as roads, railroads, and church steeples, are usually accurately located on maps and should be given first preference as map spots. The centerline of a road may be selected as an azimuth line instead of an orienting point. Streams and ridgelines also make good map spots. 272. Magnetic Azimuth The direction of the earth's magnetic field is determined by use of the aiming circle. For GN • GM GRID CONVERGENCE a. GRID CONVERGENCE DECLINATION CONSTANT c . • WEST MAGNETIC DECLINATION GRID CONVERGENCE e. operation of the aiming circle, see paragraphs 145 through 156. A correction is apvlied to the aiming circle to convert the magnetic azimuth to grid azimuth. The angle between true north and magnetic north is called the magnetic declination. It is named east if the needle points east of true north and west if the needle points west of true north. The horizontal clockwise angle between grid north and magnetic north is called the declination constant or the grid azimuth of magnetic north. The grid-magnetic GN WEST DECLINATION MAGNETIC CONSTANT DECLINATION b. GN • GRID CONVERGENCE EAST MAGNETIC DECLINATION d. • EAST MAGNETIC DECLINATION GM ANGLE f. Figure 103. Declination diagrams. AGO 10005A angle is the angle between grid north and mag netic north and is always the smaller of the two angles between these lines. The grid converg ence is the angle between grid north and true l 200 FT-l-200FT-1 200FTl-200FT J north. On the margin of a military map, a ~\\\\\\) declination diagram shows two of these values ~CJ from which the others may be derived. There MAGNETIC MAS~are six possible diagram arrangements (fig. Figure 104. Detecting hidden magnetic disturbance. 103). Shown under the declination diagram is the effective year of the diagram with an 1 headquarters has tested the site and found it annual rate of change. When a person arrives free of magnetic disturbance. in a new area and has no opportunity to declinate a compass at a declination station, he may obtain the declination constant from the 274. Declination Stations declination diagram on a local map. In two Corps artillery, division artillery, and, in cases (b and c, fig. 103), the declination consome cases, artillery battalion survey teams stant is shown directly on the diagram. In two will establish declination stations for use by cas.es (a and f, fig. 103), the grid-magnetic anfield artillery battalions in declinating their gle shown on the diagram must be subtracted aiming circles. A declination station is a point from 6,400 to obtain the declination constant. free of local magnetic disturbance with two or In one case (d, fig. 103), the declination conmore orienting points of known grid azimuth. stant is the sum of the grid convergence and the The site selected for a declination station magnetic declination. In the remaining case ( e, should be free of visible magnetic disturbance, fig. 103), the sum of the grid convergence and accessible from the local road net, and centrally the magnetic declination must be subtracted located to the using units. The procedure in from 6,400 to obtain the declination cons.tant. paragraph 273 should be followed to determine In all cases, the declination constant must then that the area is free of hidden magnetic disbe corrected for the annual change. The annual turbance. One of the methods outlined in thisrate of change is multiplied by the number of section which does not involve the magneticyears since the date of the diagram. If the field should be used to establish a grid azimuthannual change is listed as easterly, the product to two or more orienting points. The identificais added to the declination constant. If the tion of the station, a description of eachannual change is listed as westerly, the product orienting point, and the grid azimuth of each is subtracted from the declination constant. point should be written on a tag and the tag attached to the witness stake at the station. The 273. Detecting Hidden Magnetic Disturbance following minimum distances from common The presence of a hidden magnetic disturbmagnetic dist urbances are prescribed: ance can be detected by measuring the magnetic 150 meters Powerline --------------------------- azimuth of a line from both ends. A difference 150 meters Electronic equipment -----------------in the two measurements in excess of the Railway tracks ----------------------75 meters 75 meters normal reading error of the instrument indi Tanks and trucks -------------------- 50 meters cates the presence of a local magnetic disturbLight trucks ------------------------Wire or barbed wire fences -----------30 meters ance (fig. 104). If both stations selected are on Helmets, etc -------------------10 meters the same side of the disturbance, the difference in the measurements is much smaller than if 275. Procedure for Declinating the Aiming the st ations were on opposite sides of the dis turbance. The magnetic azimuths must conCircle at a Declination Station tinue to be measured from additional stations When a declination station is available, the until the difference in the measurements is procedures in declinating the aiming circle aretolerable. This precaution should be taken each as follows: time the compass is used except at a declination a. Set up the aiming circle in the prescribed station, when it may be assumed that higher AGO 10006A 176 manner. Level the instrument and perform the may have occurred due to accidents to the in checks outlined in paragraph 156. strument which were not reported. If a radical b. Set the known grid detection to the change is observed, the instrument should beredeclinated again within a few days to deter azimuth mark on the scales of the instrumentand, with the lower motion (nonrecording), mine if the observed change was due to a magsight on the azimuth mark. netic storm or is a real change in the characteristic of the instrument. c. Release the magnetic needle. With theupper motion (recording), center the needle d. The aiming circle should be declinatedthrough the magnetic needle magnifier. when it is initially received and redeclinatedwhen it is returned from ordnance repair. d. Read the declination constant directly Variations in the declination constant due to from the scales (to 0.5 mil). the time of day are not significant enough to e. Relevel the aiming circle; repeat b through warrant a redeclination at any specific time.d above. Determine a second declination constant by using a second known azimuth mark 277. Azimuth by Simultaneous Observationsif one is available; if a second known azimuthmark is not available, use the same azimuth a. Because of the great distances of celestialmark. bodies from the earth, the directions to a celestial body at any instant from two or more close f. Compare the two declination constants points on the earth are approximately equal. determined. If they vary more than 2 mils, The difference between the azimuths is primarrepeat the entire procedure. If they agree ily due to the fact that the azimuths at different within 2 mils, determine the mean and record points are measured with respect to different it to the nearest 1 mil on the notation strip of horizontal planes. This difference can be deterthe aiming circle. mined. The principles in b below provide asimple and Tapid means of transmitting direc 276. When To Declinate the Aiming Circle tion between points by simultaneous observaCertain rules prescribe how often and under tions. In general, it is easier and more accuratewhat circumstances the aiming circle should to ob erve an astronomic azimuth at eachbe declinated to determine and to keep current location. the declination constant. These rules are as b. A master station is established at a point follows: which can be identified on a large-scale map a. As a general rule, the aiming circle should and from which the grid azimuth to an azimuthbe redeclinated when it is moved 25 miles or mark is known or has been determined. Flankmore from the area in which it was last decstations are established at points which can belinated. A move of any appreciable distance (a identified on a large-scale map and at which itfew miles) may change the relationship of grid is desired to determine common grid azimuths.north and magnetic north as measured by the Wire or radio communication must be availinstrument. In some locations, a move of less able between each flank station and the masterthan 25 miles may require redeclination of the station. An observing instrument is set up ataiming circle. the master station and oriented on the azimuthmark. An observing instrument is set up at b. The aiming circle must be redeclinatedafter an electrical storm or after receiving a each fl ank station and oriented on an azimuth severe shock, such as a drop from the bed of a mark to which the azimuth is desired. (Direction can be transmitted to more than one flank truck to the ground. The magnetic needle is a delicately balanced mechanism, and any shock station at the same time.) A prominent celestial body at an altitude between 10° and 65 ° is may cause a significant change in the dec selected by the observer at the master station lination constant for the instrument. and identified to the observer at each flank c. The aiming circle should be redeclinated station. The observer at the master stationevery 30 days to guard against changes which must wear a lip or throat microphone so that AGO 10005.\ 177 ..________ --- he can transmit information at the same time crosshair (crossline). The master station obthat he is observing a celestial body. A loudserver announces "Tip" the instant the star is speaker, headset, or other device must be proat the intersection of the crosshairs or the in 4 stant the sun is tangent to both crosshairs. Thevided the observer at each flank station so that master station observer records the readings he can hear instructions from the observer at the master station. The master station observer on the horizontal and vertical scales (fig. 105). reports his coordinates (encoded if necessary) Each flank observer records the reading on the to each flank station observer, and each flank horizontal scale when observing the sun and the readings on the horizontal and vertical scales station observer notifies the master station observer when he is ready to observe. When all when observing a star (fig. 106). The vertical angle is read at the flank stations only as an aid observers are ready, the observer at the master station announces "R eady_ begin tracking_ in identification. All observers then plunge their telescopes and repeat the procedure with the 3-2-1-tip." Paintings are made on the celes tial body as explained in chapter 13, depending telescopes in the reverse position, using the rocedure required for their instrument. With on which instrument is used. However, each p flank station observer, if he is observing the the aiming circle, two readings are taken. If sun, keeps his vertical crosshair (crossline) 0 bserving the sun, each flank station observer tracks with the vertical crosshair tangent totangent to the leading edge of the sun and apthe trailing edge of the sun. After both pointproximately bisects the sun with the horizontal C.HI£f OFPIJRTY: 5GT D/clvN to D {,O'fi. 171 /,()lj'f. 57 1117.0.2~:+402. 971.. Az A I< MS . 0f R ;J.f50!f77 .5/1'/-.3/. +38l/.31.. 7 WATER OW&R I OOM sJ U' 1/IJ COM UTI/Ttt~N OFI/Z (J StiN: A.zAipi/M5 Tc Wr -« .J.WT ·APflf>15· 0/11 (;,(J ~'1. 3(l~ '~3 5"1-~.13 -k.4oo.boo Ai!. , 1/JJlMS T, Si/N : 3'154. LY3~ I tJI ~ I~ I -i--...f!..!!M.: ~!il>__j_ d----- r I ~---------_;P AD r / kd I ~ .... / I I ,"~-' '-~ Figure 105. Recorder's notes made at the master station for a simultaneous obs ervation. A GO 10005A ~ 178 - DESIGNATIONSIMULTAHE.Ou..s.Jl!~TE 1.8 JUL 19 ~IVfiTAL STATION -r a MIL~ /111N ST,cl :Z./ D oooo./511. R lna.I!J!f..3 ~~ll~ sTA Z'2- NIN _CILtl_,_l ii 2 UN _pi_O 1//•tJ. 112. J/91.29, -~~ w~'lJ.!llL I ---1--- I -~ ----+----- -~ ---r- -- I --r-- ~~_:!: - F ig ure 106. R ecorder's notes simultaneous ings, each flank station observer acknowledges if the observation was successful. He reports " Take again" if the observation was not successful. After each set of pointings in which one or more flank stations tracked successfully, the horizontal angle at the master station, from the azimuth mark to the celestial body, is determined from the observed data. This horizontal angle is then added to the grid azimuth from the master station to the azimuth mark to obtain the grid azimuth to the observed celestial body. This grid azimuth and the mean vertical angle to the celestial body are transmit ted to each flank station. c. At each flank station, the locations of both stations are plotted on a large-scale map (fig. 107). A line is then drawn on the map representing the azimuth to the celestial body at the AGO 10005A c.IUEF OF PIIT?TY: 5(,1 /fE£DY21 uJE.IiTH£8 : COOL. ·CLEM 08SER\IE.R: Sui THOMOot.\ 111/STRUMf:NI 1\10 · T2.~11'12. fH'o~DfK· en HDFHDf RE.M jqR K1\ STil /()/{ ~0 .s FLIIN~ STI/710W I..OCJI irED 30M SU. OF FOil D tJN D'tlmr Ro 5M lt' t IF1..111/GE .84VJ. 0~IR. sT.In /NY ~I lis ,qz M~. J./Jc~ 'EP~gd#/ s or STA INy ,?Q ;t3M kl dE Lt~IYE r, 'EE. 8tJ II 5TIIrl11# MANKE t> BY N /1.. 11&1/Di> 1/'1 " ''} " ,, C"NC,fE E BLoc ~'5 PKdJ!J: cTIIVG :?" ABPVE GRovNt . C~MPtl ~77"¥" ,tl~ S7A1.:Jq 7P .5: 'A.U: IA#l (M4S1t;:g) Ahl1J~(' Tit <'(J'tl "?q5~ . t.5? :r ..I + . 41./J ',.,{ I 39.5S 11.13 illllf.LE SliJJ .11-<::n 'Jn. <:.f)~ -Jl q :J. • 1119 IA,;l ~TA ..7n-...-T. .:111>2 .~95--' ~I I I~ / / I I~ /..:o, J 1 __11_~ / \ - I 0\ 'T"l ~~ 9 ~ ri~ ....,-, .,o/\ \ , 'I .\.[\ I '' ' 1-/\ ~ I -r~ ' I ' ~ \ ~ " ¥3~~~~ 5T/l :1.1 made a t a flank station fo r a observation. master station. The perpendicular distance (D) to this line from the flank station is then measured. d. A line is drawn on the nomograph shown in figure 108 (also contained in TM 6-300-( ) , Army Ephemeris ) to connect the mean observed altitude at the master station (H) and the distance (D). This line will intersect the center scale (C) at a point corresponding to the correction in mils (or seconds) to be applied to the azimuth at the master station to determine the correct azimuth from the flank station to the celestial body. When the nomograph is used, it may be necessary to multiply the indicated value in meters by 10, 100, etc. In this case, the indicated correction in mils (or seconds) must also be multiplied by the same number. The correction is applied to the grid azimuth of the 179 azimuth mark to the celestial body, is then subtracted from this azimuth to obtain the grid azimuth to the azimuth mark. For this sub N FLANK STATION \ I \ \ ~ C (CORRECTION IN SECONDS) Figure 107. Relative locations of the master station, the flank station, and the celestial body. celestial body (determined at the master station) in accordance with the following rules: ( 1) When the flank station is to the left of the line from the master station to the celestial body, the correction is added to the azimuth. (2) When the flank station is to the right of the line from the master station to the celestial body, the correction is subtracted from the azimuth. e. The corrected azimuth obtained in d above is the grid azimuth of the celestial body from the flank station. The mean of the observed horizontal angle at the flank station, from the traction, it may be necessary to add 6,400 mils or 360 ° to the azimuth of the celestial body. f. If necessary, the master station may use an assumed starting azimuth to the azimuth mark. 278. Example of Computations for Simultaneous Observations The following example illustrates the transmission of direction to one flank station by simultaneous observations: a. Mean recorded angles: Master station Horizontal angle=2191.421 mils Vertical angle = 720.063 mils Flank station Horizontal angle=1715.063 mils b. Grid azimuth to azimuth mark at master station: 1874.537 Mean observed horizontal angle at master station: +2191.421 Grid azimuth to star at master station: 4065.958 Correction from nomograph (c below): + 0.680 Grid azimuth to star at flank station: 4066.638 Mean horizontlll angle at flank station: -1715.063 Grid azimuth to azimuth mark at flank station : 2351.575 c. The relative locations of the master station and flank station and the star are shown in figure 107. The distance (D) is scaled from this figure to enter the nomograph in figure 108. The correction to the azimuth of the star is scaled from the nomograph as +0.68 mil and is used in t he computation above to convert the grid azimuth of the star from the master station to the flank station. AGO 10005A TABLE 13. Grid Azimuth Correction, Simultaneous Observation D c H METERS SECONDS MILS DEGREES MILS 1000 70" 60" 0 .30 rr( 1100 rr( 50" 800 so• 40" 0 .20 rr( 700 1000 rr( 30" 600 900 rr( so• 20" 0 .10 rr{ 0. 0~ rr{ 500 0 .08 rr{ 800 rr( -<2.02111' 0 .06111' ----- - 4oo 400 700 rr(10" 0.05111' 8" 0.04 rr{ 600 rr{ D= Perpendicular distance from flank station to .. o line representing azimuth from master 6 0 .03111' 300 station to sun or star. If D exceeds 1000 meters, a multiplier of 10 , 100, etc is used . 500rrf' H = Observed altitude from master station to sun or star. 0.02 rr( C • Correction to be applied to azimuth from master station to sun or star to obtain corrected azimuth from flank station to sun or star . 400 ,.,( Correction is plus if flank station is to the left of a line from the master station to 200 sun or star, minus if to th~ right . 0.01 rr{ D=5000 meters H • 40" 30' (or 720 mils) With a straight edpe, line up 500 an D scale and 40"30 (or 720 mils) on H 300 rr( scale. The correction C=13.8 (or 0 .068) x 10 = 138 seconds (or 0.68 mils). In this case 500 is multiplied by 10 to make it 5000, so the correction for azimuth from C scale must also be multiplied by 10. I" 0.005 rr{ 200 ,.,( 0.511 F·igurc 108. Simultaneous observation, grid azimuth correction nomograph. AGO 10005A 18 1 CHAPTER 13 ASTRONOMIC AZIMUTH Section I. GENERAL 279. General NORTH CELESTIAL POLE a. The tactical situation will dictate the time and place that astronomic azimuth may be taken. The artillery surveyor must select the celestial body and method of computation which will give the required accuracy in the time available. Astronomic observation is the fastest independent method of determining direction available and should be the first choice if visibility and other required conditions can be met. b. Both the geographic and UTM coordinates of the observing station are required for computations. The position selected, within the area dictated by the tactical situation, should be such that one of these values is either known or can be scaled from a map. The effects of refraction on observations are discussed in paragraph 294. SOUTH CELESTIAL POLE c. The specifications and the limitations disFigu1·e 10.9. The celestial sphe1·e. cussed in this chapter are intended to meet the most stringent artillery requirement. When a b. The plane forming the earth's equator when extended to the celestial sphere inscribes lesser accuracy will suffice, some of the requirements may be lowered to meet the tactical the celestial equator on the celestial sphere. situation. c. The extension to the celestial sphere of any plane forming a meridian of longitude on 280. The Celestial Sphere the earth forms a corresponding meridian on In practical astronomy, it is assumed that the celestial sphere which is called a celestictl the sun and stars are attached to a giant sphere, me1·idian or hoU?· circle. the center of which is the earth. The stars are d. The ecliptic is the great circle cut on theso far away from the earth that the radius of celestial sphere by the plane of the earth'sthe sphere is assumed to be infinite. Some parts orbit. Since the sun lies in the plane of theof the celestial sphere are related to parts of ecliptic, the apparent path of the sun follows the earth (fig. 109). the ecliptic. The ecliptic intersects the celestial a. The points at which the extensions of the equator at two points at an angle of about earth's rotating axis intercept the celestial 23 V:! 0 These points are called the equinoxes. sphere are called the north and south celestial • e. The point at which the apparent sun,poles, respectively. AGO 10005A 182 moving from south to north, crosses the celestial equator is known as the vernal equino~r. This is the point on the celestial sphere used as a reference for sidereal time and the apparent places of the stars. 281. Observer's Position a. The zenith and nadi1· of the observer's position on the earth's surface are the two points on the celestial sphere where the extended plumbline of the observer's instrument intersects the sphere. The zenith is the point directly above the position, and the nadir is the point directly below the position. b. The observer's geographic locations are as follows: ( 1) The latitude of the observer's location is the angular distance of that point north and south of the equator. (2) The longitude of the observer's location is the angular distance of the observer's meridian east or west of the Greenwich meridian, as measured on the equator. c. The line of longitude which passes through the observer's position is called the obse1·ver's meridian. The celestial meridian which passes through the zenith is called the observer's hour circle (fig. 110). Both meridians lie in the same plane. d. The obseiTPr's horizon is a circle on the celesti al sphere, formed by a plane tangent to the earth at the observer's location and perpendicular to the plumbline of the observer's instrument (fig. 110). e. A ve1·tical circle is any great circle on the celestial sphere passing through the zenith and nadir of a point (fig. 110). f. The }J1'ime vertical is the vertical circle perpendicular to the observer's meridian at the zenith, which intersects the horizon at points directly east and west of the observer (fig. 110). 282. Position of a Celestial Body The system of locating a celestial body on t he celestial sphere is much the same as that of locating the observer on the earth. The two coordinates in this system are 1·ight ascension (RA) and declination (dec) (fig. 111). This system is used to list the stars in the Army Ephemeris. a. Right ascension is comparable to longitude and is the angle in hours (h), minutes (m), and seconds (s) measured eastward from the vernal equinox to the hour circle of a celestial body. b. The declination of a celestial body is com- Figure 110. Elements relative to observer's position. Figure 111 . Locating a celestial body. AGO 10005A parable to latitude and is the angle measured north or south of the celestial equator to a celestial body. If the celestial body is north of the celestial equator, the declination is ( +) ; if it is south, the declination is minus (-). 283. Astronomic Triangle Determination of azimuth by astronomic observations involves the solution of a spherical triangle visualized on the celestial sphere (fig. 112). This triangle is called the astronomic triangle or the PZS triangle. The desired azimuth to the celestial body is determined by solving the triangle for the value of the azimuth angle. This value can be computed when three other parts of the triangle are known. The letters PZS stand for the three vertices of the triangle; namely, the celestial pole (P) the zenith (Z), and the star or sun (S). The three sides of the triangle are the polar distance, the coaltitude, and the colatitude. The three angles are the parallactic angle, the azimuth angle, and the local hour angle. When a survey is conducted Local hour angle Parallactic angle at ion Figure 112. Celestial sphere with three sides and three angles of the astronomic (PZS) triangle. south of the equator, the north pole is used unless computations are performed by the hour-angle method, in which case the south pole is used. The azimuth angle may be either east or west of the pole used. 284. The Sides of the Triangle Each side of the astronomic triangle is the cofunction of a known or measured value. The cofunction is defined as 1,600 mils, or 90 ° minus the function. Thus, the colatitude, or PZ side of the triangle, is equal to 1,600 mils minus the latitude. The coaltitude, or SZ side, is 1,600 mils minus the altitude. The polar distance, or PS side, is 1,600 mils minus the declination. In most cases, the formulae used by the artillery have been arranged so that the known or measured value is used rather than the cofunction. 285. The Angles of the Triangle The angles of the astronomic triangle are as follows: a. Pamllactic A ng le. The parallactic angle is the interior angle at the celestial body and is used in the formula for determining azimuth by the hour-angle method but cancels out in the computat ions. b. Azimuth Angle. The azimuth angle is the interior angle of the astronomic triangle at the zenith. This angle is the result of computations and is used to determine the true azimuth to the celestial body from the observer. The angle can be either to the east or west of the observer's meridian, depending on whether the celestial body is east or west of the observer's meridian. When the south pole is used to determine the azimuth angle, the angle must be changed to the north by adding 3,200 mils. c. Local Hour Angle. The local hour angle is the interior angle of the astronomic triangle at the pole and is used in the hour-angle method of determining azimuth. Section 286. General a. Time is an angular measurement. One complete rotation of the earth is 1 day. Each day is divided -into 24 hours of 60 minutes each, and each minute is divided into 60 seconds. In II. TIME artillery computations, angular measurements. are usually expressed in mils. Table 5 in the Army Ephemeris is used to convert time to mils. b. Solar time is the hour angle of the sun AGO 10005A plus 12 hours. Since the apparent sun does not Table II. Time Zone Corrections, Local Mean Time tomove at a uniform rate, time is based on the Greenwich Mean Time. mean movement of the sun. Greenwich mean Correction Time zone Correction time (GMT) is the hour angle of the mean sun (hours ) Time zone (hours ) from the meridian of Greenwich plus 12 hours. z Greenwich 0 z Greenwich 0Mean time is the hour angle of the mean sun (GMT) (GMT) A 15• E from the standard time zone meridian plus 12 B 30• E -1 N 15° w. +1 hours. -2 0 30° w +2c 45 • E -3 p 45° w +3 E D 60 • E -4 Q 60° w +475 ° E -5 R 75 ° w 287. Standard Time and Time Zones F go· E -6 s go · w +5 Watch times are based on standar d t ime G 105• E -7 T 105 ° w + + 7 6 H 120• E -8 u 120° wzones, each of which cover s a portion of the I 135° E _ g v + 8 135° w +gearth. In a zone of operations, survey personnel K 150° E I -10 w 150 ° w + 10 165 ° E I -11 X 165° w using astronomic observations must know the L + 11 time zone on which their watch time is based. l\1 1so· E -12 l y 1so· w + 12 The time zone on which a watch time is based Note. Each of t h ese zones is n amed by local civilauthority. For example, in the United States, time can be determined from the survey information zone Q corresponds to easteTn daylight saving time;center (SIC). (Time zone corrections are given time zone R corresponds to easte1·n standa1·d time andin table II.) Local mean time (LMT) changes cent1·al daylight saving tim e; t ime zone S correspondsto cent1·al :>tanda?·d time and mountain daylight saving1 hour for each change of 15 ° of longitude. time; time zone T corresponds to mountain standardSince the sun appears to move from east to time and Pacific daylight saving time; and time zonewest, time increases from west to east and deU corresponds to Pacific standard time. creases from east to west. For example, with 288. Source of Accurate TimeGreenwich as a baseline for time measurement, a. All major nations furnish a radio timetime decreases 1 hour for each change of 15" signal of a high order of accuracy for use byof longit ude (arc) westward from Greenwich. scientists and navigato rs. The method of obTime differs in whole hours from Greenwich taini ng t he co rrect time f r om such radio sigmean time at 15 ° W, 30 ° W, 45° W, etc. (table nals is expla ined in detail in TM 5-441. TheseII). To standardize the time within a cer t ain radio signals are the preferred and most accuarea, lines of longitude at which time differs rate time source. from Greenwich mean time in whole hours. are b. The s urvey information center is issued aused. A time zone area extending 7%o from chronometer which is capable of maintainingeach side of these lines has the same time as time to an accuracy sufficient for artillery surthat meridian unless otherwise specified by vey use. For the use of those artillery surveycivil authorities. For example, the time zone ors who are not equipped with a radio whichfor the 45 ° W meridian would extend from will receive the time signals referred to in a37° 30' W to 52° 30above, the SIC furnishes accurate time. The ' W. In the Unit ed States there are four time zones. These zones are based SIC maintains, in a bound book such as DAon the 75 ° W, 90 ° W, 105° W, and 120° W Form 5-72, a log of the chronometer so that meridians and are called eastern, time accurate to 0.2 second can be furnished by central, t elephone, radio, mountain, and Pacific standard times, respector direct comparison of ively. watches. The record is kept in the following manner: I method, it will usually suffice. The habit ofThe date and time is obtained from one of the using time from the SIC should be formed inradio t ime signals listed in TM 5-441. Computaorder to obtain the most accurate time possible. 4tions can be simplified if the signal is obtained at the same time each day. A comparison of the chronometer time and the radio time should be 289. Greenwich Mean Time made to the nearest 0.1 second to provide time All computations of astronomic observations accurate to 0.2 second. The chronometer corin the artillery are based on Greenwich mean rection at the time of the comparison is the time (fig. 113). Greenwich mean time is dedifference between the chronometer time and termined for the local mean time of observation the time obtained by radio. The sign of the by applying a correction fo r the difference in correction should reduce the chronometer time hours between local mean t ime and Greenwich to correct time. The difference column is the mean time. For example, if the longitude of the change in the correction between the current observer is 92 ° 13' 42" W and the civil, or chronometer comparison and the last chronomean, time at that point is based on the stand meter comparison. The sign of this difference ard time of the 90 ° W meridian, a 6-hour dif should reduce the previous chronometer correc ference, or correction, must be applied to the tion to the current correction. This should be local mean time of observation in order to de in seconds of time. The elapsed time is the diftermine the Greenwich mean time of observa ference in decimal parts of a day between the tion. last two comparisons. The daily rate is obtained by dividing the difference column by the elapsed time in days and carries the same sign as the 290. Apparent Solar Time difference column. The daily rate is a measure As noted in paragraph 286, the mean posi of the amount of time the chronometer loses or tion of the sun is used to measure mean time. gains in a day. The chronometer should be When observations are made on the sun, the wound at the same time each day in order to actual or apparent sun is observed. Conse maintain a uniform rate. The chronometer quently, when astronomic computations involv must never be allowed to run down and should ing the hour angle of the sun are performed, never be set. When the survey information cenapparent solar time is used (fig. 114). The ter is moved, the chronometer must be handled actual hour angle of the sun referred to the with care. observer's meridian is the local apparent time plus 12 hours. The local apparent time is ob c. Message center time is. used to synchrotained by changing the time of observation to nize military tactical operations and, in general, is not accurate enough for astronomic use. Greenwich mean time, which is the basis for the tables of the Army Ephemeris, TM 6-300-However, when observing the stars (sun) by ( ) . The equation of time, which is the differthe altitude method, or Polaris by the Polaris teo• 180° GREENWICH-MEAN TIME CELESTIALNORTH NORTH POLE CELESTIAL '· '· REAL OR GREENWICH APPARENT APPARENTOBSERVER'S GREENWICH TIMEMERIDIAN '... MEAN TIME MERIDIAN TIME ZONE CORRECTION GREENWICH MER I 01 AN Figure 114. Apparent solar time. Figure 119. G·reenwich mean time. AGO 10005A 186 ence between the mean sun and the apparent sun, is then obtained from table 2 of the Army Ephemeris and is added to Greenwich mean time to obtain Greenwich apparent time (GAT). The longitude of the observer's meridian at the time of observation is then added to, or subtracted from, the Greenwich apparent time. The result is local apparent time. In west longitude, the longitude of the observer's meridian is subtracted from the Greenwich apparent time; in east longitude, it is added. These computations may be performed in hours, de grees or mils, whichever is most convenient. All times must be converted to the same unit before performing the addition or subtraction, and the final answer must be reduced to mils for use in computations. 291. Sidereal Time Time is an angular measurement of the rotation of the earth using various reference points. The basic reference point for sidereal time is the vernal equinox. One sidereal day is the length of time it takes the earth to complete one revolution with respect to the vernal equinox. The sidereal day is nearly 4 minutes longer than the solar day. The rotation of the earth on its own axis added to the rotation of the earth around the sun to complete one revolution of the earth with respect to the sun takes less time than one revolution of the earth with respect to a fixed point in space. a. The position of the stars on the celestial sphere with respect to the vernal equinox is an angle called the right ascension. Because the stars move so slowly in space, they can be listed in terms of right ascension and the listing will not change. If the time of observation is converted to sidereal time which is also referred to the vernal equinox, the hour angle of the star can be obtained by simple addition. b. The local sidereal time, which is the hour angle of the meridian of observation referred to the vernal equinox, is obtained by converting th e time of observation to Greenwich mean ti me by applying the time zone correction. Greenwich mean time is then converted to Gr eenwich sidereal time (GST) by obtaining the sidereal time of Oh Greenwich from table 2 of the Army Ephemeris and adding the correction for the fraction of a day as contained ·in table 4. The longitude of the observer's meridian is then applied to Greenwich sidereal time to obtain local sidereal time (LST) (fig. 115). Figure 115. Side1·eal time. Section Ill. DETERMINING FIELD DATA 292. General Field data for determining azimuth by astronomic observation consists of the horizontal angle between an azimuth mark and the observed celestial body, the vertical angle to the body, the time of the observati?n, the temper~ture at the time of the observatiOn, the approximate azimuth to the azimuth mark, and the location of the observing station in both geographic and grid coordinates. All of these should be observed and recorded at all astronomic stations. AGO 10005A 293. Selection of Site Within the limits imposed by the tactical situation, the exact point selected for the observations can improve the accuracy of the observations and make the computations simpler. Refraction is the first major considerat ion in the selection of a site. The site must be so located that the effect of refraction is reduced as much as possible. Both the geographic and UTM coordinates of the site are requ ired in computations. These are usually I Angles are determined in astronomic observa obtained by scaling the position from a map. tions in much the same manner as in any other The point selected should be one that can be located easily on a map. An alternate to map method of survey; i. e., the angles are deter 4 mined by co mparing the mean pointing to one spotting is to select a survey control point and use the surveyed coordinates. station with the mean pointing to another. Since celestial bodies appear to be moving, the technique of pointing is slightly modified. Also, 294. Refraction sin ce the sun presents such a large target, VVhen light rays pass through transparent special techniques must be employed to detersubstances of different densities the light rays mine its center.are bent. This effect is called refraction. It is easy to observe this effect when looking b. Vertical angles are usually larger than in normal field operations. Con sequently, errors obliquely into a pond of clear water. VVhen look in leveling can cause large errors in t he hori ing straight down into the water, the effect is zontal angles. More than normal care is re not visible. Light rays are also bent, but to a lesser degree, when they pass through layers or quired in leveling. The plate level should be bodies of air at different temperatures or denchecked after each pointing on the star or sun. sities. Refraction is still great enough, however, If the vertical angle exceeds 800 mils, leveling to affect the angles measured. VVhen observing becomes even more critical. Since the level vial a star (sun), the observer's line of sight passes is perpendicu lar to the line of sigh t, leveling through the earth's atmosphere out into space. wi ll not require additional time. The earth's atmosphere is composed of numerc. A "position" is a complete set of data ous layers of air of different densities. As the starting with the initial pointing on the aziline of sight passes through each layer, it is muth mark and ending with the pointing on the bent s lightly. The sum of all the bending is the azimuth mark with the telescope reversed. At vertical refraction. The effect of refraction is least three positions which agree are required not visible when the observer looks straight up. for a check. The position may be started with VVhen the observer looks horizontally the verthe telescope in the direct or reverse position, tical refraction is maximum. The mean vertical and some time will be saved if alternate porefraction correction for average conditions has sitions are started with the telescope reversed. been computed and is listed in table 1 of the Agreement between positions or sets is checked Army Ephemeris. The probable error of this by plotting the mean horizontal angles and correction is not too large for artillery survey vertical angles against the mean times of the purposes. Since no correction can be made for pointings. The plot should be a straight line horizontal refraction, it is adviseable to avoid within the limits of accuracy of the instrument. an instrument position where there is a large This plot should be made by the recorder before variation in local temperature. the instrument operator removes his instrument from the tripod. 295. Temperature In units equipped with a thermometer, the 297. Use of the Theodolite With Solar Circle temperature at the time of observation should for Sun Obsl'!rvations be recorded. Temperature, to the nearest deThe T16 theodolite and the later model T2 gree, and the vertical angle are used to enter theodolite are equipped with a solar circle on table la or lb of the Army Ephemeris to deterthe reticle (fig. 116) . The solar circle permits mine the refraction correction. an observer to view the sun in such a manner that the vertical and horizontal crosslines of 296. Determining Horizontal and Vertical the instrument are directly over the center of Angles the sun. The initial pointing on the azimuth mark is made with the telescope in the direct a. The instruments used to observe celestial bodies are the aiming circle, the T16 theodolite, position. The telescope is then pointed toward the sun. The sun is placed on the solar circle or the T2 theodolite. Instructions for use of and tracked by using both the horizontal and these instruments are found in chapter 7. AGO 10011 5A 188 vertical tangent screws. When the sun is nearly circle for pointing on the center of the sun. Tocentered in the solar circle, the observer warns achieve measurements to the center of the sun,the recorder by saying "Ready." At the word the observer measures the angles to one side of"Ready," the recorder looks at his watch, getthe sun with the telescope in the direct posi ting the second beat in mind. The observer cention and then to the other side of t he sun withters the sun in the solar circle and announces the telescope in the reverse position (fig. 117) ." Tip." At the word "Tip," the recorder enters The resulting mean angle is the angle to thethe time in the record book. The observer checks center of the sun. This method of determiningthe plate level and levels the collimation level the center of the sun is called the quadrant bubble and then reads the vertical and horizonmethod and can be used either when the sun istal circle readings. The recorder must have re viewed directly through a sun filter or when corded the time before accepting the angles. The telescope is then plunged, and the process the image of the sun is projected onto a card is repeated with the telescope in the reverse held to the rear of the eyepiece of the telescope. To determine the correct quadrant in which position. With the telescope still in the reverseposition, the final pointing is made on the azito place the image of the sun , the observer first determines the direction the sun is moving. If muth mark. The mean data can now be deter mined. the motion of the sun is through the first andthird quadrants (from first to third or fromCaution: Do not view the sun directly third to first) as viewed through the telescopethrough the telescope unless the sun filter or on the card, the image of the sun should behas been affixed to the eyepiece. placed in the second and fourth quadrants. If the motion of the sun is through the second and 298. Use of Instruments Without the Solar fourth quadrants (from second to fourth orCircle for Sun Observations from fo urth to second), the image of the sun a. The early model T2 theodolite and the shoul d be placed in the first and third quad rants. aiming circle are not equipped with a solar 1\ b. The instrument is set up over the stationselected. With the telescope in the direct position, t he observer makes the initial pointingon the azimuth mark. In those instrumentswith do uble vertical crosslines, the quadrantsselected must be such that the double crosslineis not used. The image of the sun is placed inthe telescope so that it is in the proper quadrantand position. When a card is used for morning observation with the telescope in the direct position, the disc should be in the third quadrant hanging on the horizontal crosshair andslightly over the vertical crosshair. c. Using the vertical motion, the observermaintains the sun's image tangent to the horizontal crosshair and allows the movement ofthe su to bring the sun tangent to the vertical crosshair. The observer alerts the recorder bycalling "Ready" and announces "Tip" at theexact moment when the image of the sun istangent to both crosshairs. At the word"Ready" the recorder looks at his watch, getT 16 THEODOLITE ting the second beat in mind. At the word"Tip," the recorder writes the time in the Figure 116. T16 theodolite reticle with solar circle. record book to the nearest second. The instru- AGO I0005A 189 Telescope Reversed I Telescope Direct 4 (2) Track with horizontal motion (I) Track with vertical motion Figure a. Sun's actual motion on card with T-2 theodolite (AM observations ) Telescope ReversedTe Iescope Direct (2) Track with vertical motion (I) Track with horizontal motion Figure b. Sun's actual motion on card with T-2 theodolite (PM observatio·ns ) Figure 117. Method of observing to determine the mean center of the sun. horizontal and vertical angles. The recorder ment operator glances at the level vial to verify enters each angle in turn and repeats it as enthat the instrument is level, brings the collima tered. The telescope is then reversed, and thetion level vial into adjustment, and reads the AGO 10005A 190 ______________ _, operation is repeated in the opposite quadrant. hairs are on the center of the star. The proceAfter the reverse pointing on the sun and with dure for recording is identical with that usedthe telescope still in the reverse position, the for observations on the sun as described ininstrument is turned to the azimuth mark and paragraphs 297 and 298. the horizontal and vertical angles are read and recorded. The mean of the direct and reverse pointings are the horizontal and vertical angles 300. Approximate Azimuth to the center of the sun. The approximate azimuth to the azimuthmark is required by the computer to determine 299. Stellar Observations the proper quadrant for the computed azimuth Stellar observations are made by pointing and to provide a check against gross blunders. The approximate azimuth is normally measuredthe intersection of the horizontal and vertical with an M2 compass. An intelligent estimatecrosslines at the star. Both the horizontal and by the instrument operator will suffice if thevertical motions are used. In the final refining M2 compass is not available. of the pointing, it is best to maintain the horizontal crosshair on the star while allowing themovement of the star to bring the vertical 301. Geographic Coordinates of the Observcrosshair in alinement. The observer alerts the ing Station recorder by calling "Ready" and announces The geographic coordinates (latitude and"Tip" when the vertical and horizontal cross-longitude) of the observing station must be (.hid o~ 'Party: S5.3~ Cec.h2Weather; Clear-Wob Ins! Qper: Spl+__l!la.rreo DESIGNATION suo_ ()b.set:JLJaliO_LL__DATE 24 Jun 19 lns~rt.Lmeol Nr·F2 5429 1?ecorder:Sp/4-"Barnes J.lo,.i%on~ol Verkic.ol Ve rlieol .C!,Anhion T h -;;Jn e _!i I4Mils Mean "'Reacfin Mils WT 0 OD0/.205 1? 3200./79 oooo. /92. SD260 11~>~4-09 26 II ~59. 590 Su.n f-hD 09 25 3b -3753..!144-7+3. 527 1+-856.473 ~1< 09 26 46 0565.619 3759.782 --1--- WT ]L _ 0800.5&2 1? 4000.527 0800.5·44 3077. 51-al--/on /; 0-:IP_coIS0260 MN4-( 09 29 16) ( 3767-9601) ('+ 870. 771) icorl-ridbe casE ~I-__in_ ,i r;Onb 7/ar Co 'c.refi!! WoSun -lz.,D 09 28 -4Z 4565.32 732-238 'rl-8,7.7{;2 1 0 ' , A:z:imu~hmark · _S_b_ailq..'"R 09 29 49 1371.681 -4568.50+ 5673.7801+873.780 ' ~u.. .,o,.~ ,·,., 1.-~~ t">n i. 'ot Oe'3 I w:J. .,...__. WT :D !'-OO.If.33 W"T .f800.4-D2 1600.418 ' "R I I Jsd SD260 1MN4. 109 32 43) 37715801 1+883.271) D=- ' "t, I,::-' I Sun ~1) 09 32 16 5374.83, 719.749 880.251 ~ -I, " IA-~ 109 33 20 2181./bO 5377-998 568'-.291 88b.29/ C!} I t1o S0260 I~ I l3D78 I I[3077J ~ I h.: J II ...... Figure 118. Recorde-r's notes for observations on the sun. AGO 10005A 191 known, the geographic coordinates must beknown for the hour-angle method of computing determined by conversion of the grid coord-~ an astronomic azimuth. The latitude of the station must be known for the altitude method. inates (ch. 16). • For both methods, it is desirable to know the c. If the geographic coordinates cannot be geographic coordinates fer the computation of determined by any means, azimuth cannot be convergence. determined by the altitude or hour-angle meth a. If the geographic coordinates of the staod of computing an astronomic azimuth. tion are not known, they are determined, if 302. Recording Field Data possible, by measuring from a large-scale map. All data will be recorded for each station, re If the grid coordinates of the station are known, they should be used to accurately plot gardless of the method of computation. This the location of the station on the map. If the provides a means of checking the accuracy of grid coordinates of the station are not known, the field data against gross blunders. Figures the location of the station must be plotted on 118 through 120 give examples of field notes for the map by caref u l map inspection . astronomic observations. Readings should be made and recorded to 0.001 mil for the T2 theo b. If the geographic coordinates of the stadolite, to 0. 1 mil for t he T16 theodolite, and totion are not known and a large-scale map is not 0.5 mil for the aiming circle. available but the accura te grid coordinates are Chief .~ Par+y : S1t Brow" 16 I Weather: Clear-Warm ln5tr: Oper~f Jones SrAR (DENEB) TZ#.54'9 1?el!order · C~t Smith DESIGNATION ns3ERVATJOAI DATE 2/i I Jun 19--'..5_ I Dl:+r u tn..ni Nf:i . J.lt~rl&ontol Vertic.ol Ve,.ilcol 4-Mi ls Mean 'Readin_g 4 Mils f._a lor CQ.a5. rei e. blt>tzK~ IAr.imu.th marl< is -r832.81/ 'Shaft S lE.e_ortin ft3_1rf 23 13 34 394!i20~ 767./89 ~ 1J£NE8 IJ 48 07-19.383 394-8.793 7l.4 . 19/ t835.8D9 0'1 top OCS wa er 'R. 23 1-f Cower. /600.423 .6.. WT D y "/Sao.-Ill 1600.4-32 'R I "V 'I j23 18 o4A 3t49.'n (+846.44 SD260 MN4- 1'1 ~ I .:;;! I 1JENEB v 23 17 32 47'19.774 754.513 +84-5...,.81 ' I 3& 155/.028 "!750."101 752.607 +847.391 ~ '~ so 260 1? 23 18 ..... .::::! _[llij] ~ ~....· R ecor der's notes f or obser vations on the sta1· Deneb. Figure 119. AGO 10005A 192 Sl:ar Observohon Ch;.~ "' 'f>a,.fy : SS'/J~ Co•'!r' n7 1!/ea-lh<:r : Clear-Cool Znsl o,r-s,l+ Warren DESI GNA TION 'Po/ari"i o 24J n ATE !.!. 19 2n<:framt!>n-i#r· 7'2"188/ -Re.!!.or: der::' Sf?_ /4-'Bgrne.s N.,.l~ll/'lftJI 7i" ~e Verfical ~rticol S~o~ion I h 1'1'1 5 I.A M;/5 Meo.n 't'eadon'"' .21. Mil<; REI'ltARk5 ~ WT "'> tJoo/.ooo La-t.il-u.d . 3~·s~·4-s· N~ 31.0/.IZ~ (?~OI.C'-3 J.o~'h so u.o f'1Ni. 22 09 oi) ( 21/7.04-2 ,/:, e· 98" 2 ''-' /8 w ( T-b/(. .32( A,~imu+h: 4 9/ n( i1.1/n+<> h C1nn··"SI,..,'· -4' 28'' ?'olori< 7) 122 02 .37 2117-990 983.8// +'-1'.189 1( 122 0.3 27 S~o.!ikr! SQ 2.6J2 is. 5318.220 2118.105 541'-.453 -t-61&.4531 ln,-,.le..JI IO~o~ SoC /..1J WT 12_-- I I-2.077. ~.},~ ·an i~ 0.30 ~oot. ooo (!Q/ Carfri.../at<> IC'nc;PI< 32~0. '18/t. ~tlt1.'1'13 ' ~P+ in l-rin:a J J.. .. SD2'o HN.l!. ( 22 ot. o4)(12117.23tt..') !..-,;,.3881 I f'on c r~te bloc~. A2.imu~~ '?oft>, ;., /) :zz OS 37 '.?/1/fJ. ()R• mark' is c:\.-tn.l=~ lc;""""'"..+,·n.. 983.770 +611..2301 p ,.. ~ht ,,., -fn.-:. or ocs ' . S42+~J{.. 542 J3078J ~ "' I*· -....:...L-'- I ~l.1 I ~ . .i~ ----- -1 -~ ~ , I --t I I I Figure 120. Recorder's notes f or observ ations on Polaris. Section IV. SELECTION OF STAR AND METHOD OF COMPUTATION 303. General covered and it becomes necessary to select anThe artillery surveyor must select a star other star for night observation, more complexmethods of selection must be used. (sun) and method of computation which will give the best results in the time available. In b. As the earth rotates on its axis, the ap this section an outline of the basic principles to parent path of each star is a circle centered on be considered in making the selection is given. the pole. The apparent rate of motion of eachThe survey officer must be so familiar with star along its path is constant. This motion canthese principles that the selection of the best be divided into horizontal motion, called thestar and method will be automatic. change in azimuth per second, and vertical motion alled the change in altitude per second. 304. Selection of Star When the star crosses the observer's meridian,its horizontal motion is maximum and there is a. During daylight hours, the only star no vertical motion. When the declination of thevisible is the sun and selection of the sun is star is greater than the observer's latitude,automatic. At night, when survey operations there will be two points on the apparent pathare conducted north of the equator and south of the star where it is a moving tangent to theof latitude 60 °, the selection of Polaris should line of sight, all of the apparent motion is verbe automatic. In the event that Polaris is cloud tical. At all other times, the rate of change of AGO 10005A 193 t__________________________ I Using the template as instructed in c above, azimuth must be considered against the change in altitude, called rate throughout this paraidentify the visible stars and note whether they fall within the area desired. Select the star that f graph. is most nearly in the best area. The worst posc. Field use of the concept in b above has sible star is a star near the meridian on the been simplified. The curves corresponding to southern horizon as such a star has a change in rates of motion of 0, 0.5, 1.0, and 3.0 have been azimuth of about 0.25 mil per second. Such a computed and drawn on plates for each of the star may be used to obtain a fifth-order azitemplates of the star identifier (para 306) used muth by the hour-angle method. Stars suitable by most field units. Appendix V shows these for computation by the altitude method are also plates to scale. To use the plates, place the the best stars for computation by the hourtemplate corresponding to the latitude over the angle method.plate in the appendix and trace the curve for the working rate on the template. A sharp g. When the aiming circle is used in astrogrease pencil will give a clear curve. The areas nomic observations, the vertical angle cannot be measured as accurately as with the theodolite between the curves are labeled as shown in (1) through ( 4) below. The dotted line indicates and a similar rate is required to obtain the a rate of zero. same accuracy. For example, if the rate is 1.0 and the vertical angle has a probable error (1) A1·ea A. Stars in this area have a rate (PE) of 1.0 mil, there will be a probable error between 0 and 0.5. They are the best stars for use in observation and of 1.0 mil in the azimuth. But if the rate is 0.5, an error of 1.0 mil in the vertical angle will should be selected unless this altitude is too high. introduce an error of only 0.5 mil in the azimuth. For this reason, unless the star has a (2) A1·ea B. Stars in this area have a rate between 0.5 and 1.0. Fourth-order azivery small rate, the hour-angle method must be used with the aiming circle. muth can be obtained from these stars using reasonable care. (3) A1·ea C. Stars in this area have a rate 305. Star Identification With Star Chart between 1.0 and 3.0. Fifth-order aziAstronomic observations for azimuth require muth can be obtained from these stars that the personnel engaged in performing the using reasonable care. fieldwork be capable of readily locating and (4) ATea D. Stars in this area have very identifying any of the stars listed in the Army large rates. If it becomes necessary Ephemeris. These stars can be identified by to use a star appearing in this area, using either the star chart or the star identifier the azimuth must be computed by the or both. The world star chart (fig. 121) shows hour-angle method. most of the brighter stars in the heavens. All the stars listed in the Army Ephemeris are d. The area above 60 ° altitude is blank be shown, as well as many others which aid the cause stars in this area should not be used. observer in locating these stars. The approxi e. It is s.uggested that only the curves conmate right ascension and declination can be taining the area of immediate interest be traced obtained from this chart or can be used as on the template, since the full set of curves may arguments to enter the chart. be confusing. To obtain a fourth-order azimuth, experienced operators may use the area marked Figm·e 121. World star chart."B" and altitudes as high as 1,000 mils (60 o). Less experienced operators should choose the (Located in back of manual) area marked "A" and altitude below 800 mils (45 o). For fifth-order work, areas marked a. Proficiency in star identification is usually "A", "B" and "C" may be used. based on a working knowledge of the constellations (star groups) and their relative loca f. When Polaris is blocked by a cloud cover, tions. Starting with such familiar constellations many of the better stars will also be cloud as Orion (a kite-shaped figure on the celestial covered. Select the best star from those visible. AGO 10005A 194 l equator visible during the winter months) or proximate true azimuth and altitude to eachUrsa Major (the Big Dipper), anyone should given star. (It can also be used to identify stars soon be able to lead himself from constellation of which the approximate true azimuth andto constellation across the sky. If, for example, altitude are known.) All stars shown on theone follows the arc of the Big Dipper, it will star identifier are listed in table 9, Alphabeticallead him directly to the star Arcturus and Star List, in the Army Ephemeris. The star eventually to Spica in the constellation Virgo. identifier consists of a base and 10 templates.Also, the end stars in the bucket of the Big Dip Ni ne templates are used in star identification.per (Dubhe and Merak, fig. 121) will lead the One template with moon and planet data is not observer directly to Leo. These two stars are used in artillery survey. A template is furoften referred to as the pointers, since they are nished for each 10° difference in latitude fromthe most common means used to locate Polaris, 5° through 85 °. One side of each template,the North Star, when followed in the opposite marked "N," is used for the given latitude indirection from Leo. Figure 121, however, does the Northern Hemisphere. The other side,not make this apparent because of distortion in mar ked "S," is used for the same latitude in the the polar areas. Unfortunately, star charts, Southern Hemisphere. The template conlike maps, must be printed on flat sheets of structed for the latitude nearest the latitude of paper, and the relative positions of some stars the observer must be used. To use the star are bound to be disturbed on the world star identifierchart. Except for the stars near the celestialequator, the distortions on the world star chart a. Select the proper template and correctlyplace it on the appropriate side of the base. are greater than they would be on a hemisphere star chart, but the world star chart is very useb. Determine the orientation angle as fol ful because the declinations and right ascenlow~ : sions are shown graphically. The star chart ( 1) Estimate the watch time at which the indicates the relative positions of the stars as observations are to begin. viewed in the sky. (2) Determine the orientation angle,using DA Form 6-21. b. First efforts should be concentrated onlearning a half dozen stars in each 6 hours of c. Set the arrow on the template over thethe right ascension, which would be useful for orientation angle. observing on or near the prime vertical or as d. Read the approximate true azimuth andeast and west stars. For instance, several stars the approximate altitude of any star on thejust east of the constellation Orion form a base that is within the observer's field of large pentagon with Canis Minor (Procyon) vision.near the center. The stars are rated in order ofbrightness from first magnitude to fifth magnie. Orient the star identifier so that the tude. Fifth-magnitude stars are the dimmest pointer on the template is pointing approxistars that are ordinarily visible without a telemately toward true south. The stars will then appear at the approximate altitudes read from scope. On the star chart, the magnitude is indicated by conventional signs which are also the star identifier; the approximate azimuth shown in the Army Ephemeris. When the locato the star is as read from the star identifier in the Northern Hemisphere or is equal to the tions of Castor, Pollux, Regulus, Alphard, andSirius in this part of the heavens are known, azimuth read from the star identifier minusit is easy to learn the locations of other stars 180° in the Southern Hemisphere. coming up from the east, as the night or season f. Figure 123 shows the entries made on DAadvances. Form 6-21 for determining data in findingand identifying stars. Instructions for the 306. Star Identifier use of the form are contained on the reverseside of the form (fig. 124). The star identifier (fig. 122) is issued to allartillery units that are issued a theodolite. It 307. Selection of Computation Methodassists in locating stars by providing the ap- There are four methods of computing astro- AGO 10005A 195 Figure 122. Star identifier. quick, and is the second fastest method. The nomic azimuth in the artillery-the Polaris method, the altitude hour-angle method, the altitude method involves the law of cosines to altitude method, and the hour-angle method. solve for a triangle with three known sides. All involve a solution of the PZS triangle. The This method is only slightly faster than the Polaris method is an hour-angle method that hour-angle method. The hour-angle method inhas been precomputed and is solved by looking volves two sides and the included angle of the up the answer in the Army Ephemeris. It is the PZS triangle and is the most time consuming fastest method. The altitude hour-angle method of the methods available. involves the law of sines, which is simple and AGO 10005A 196 l COMPUTATION AHD IHSTRUCTIOMS FOR USE WITH STAR IDENTIFIER (,/ 6-120 ) Tl~ s ILATITU~ ~1' ~LONGITUDE 1f&l STATION ZONE Of STATION 3 S OP STATION TS !;? SCHEDULE I SCHEDULE 2 SCHI!DULE 2 SCHEDULE • I PRESI!LfCT!D LOCAL DATE -I~IJPR€/ I 2 l'RESELECTED WATCH TIME .:z.ooo 2 l LONGITUDE Of STATION EAST+ WEST-~ .,r -+ + + l LONGITUDE OF CENTRAL MERIDIAN EAST- - {PROM TABLE. I OH REVERSE) • WEST+ ~ 9o~ + .+-+ • -+ -+ -+ + - s ALCE IRAIC SUM (l) AND (4) + + + ~ I' ---s SETTING FOR Oh OH LOCAL DATE (FROM TABLE II OM REVERSE ) • ~04 7 CORRECTION TO (6) FOR WATCH TIME '(FROM TABLE Ill OH REVERS! 30/ 7 I 16)+17) ~~g£ + + + I 9 REPEAT (S) + + + ~ f -- ' + + + + 10 ALGEBRAIC SUM (I) AND {t) ~ ¥97 +--+ + 10 ....JL!.!.JL ...i!.!L.!L 1-l )60. (10) ~~0 00 TO l60.. REPEAT (10) MORE THAN 360• (101-uo• ll ORIEHTATIOM ANGLE 137 ll SET POINTER OF APPROPRIATE TEMPLATE ON ORIE NTATION ANGLE (SEE GUIDE OH REVERSE) l2 NAME Of. STAR AJ."s: R A/111, 12 0 ll APRX AZI.liiUTH OF STAR 0 0 0 .27./L I ll .. CONVERT (ll) TO MILS, ., HECU.s.AAY Ill l ... 1 I Ill J I Ill... IS APRX AL TITUOE Of STAR 0 0 I -"'7 ° I J 1 COHVEAT (U) TO MIL$.. IP NECI!UARY Ill Ill dl " 1 1 1 Ill IS " 12 NAME OP STAR l3ELL~TR!X 12 12 APRX AZIMUTH OP STAIII 0 0 ~ss 0 I I . 1 .u CONVERT (U} TO MILS, If NECESSARY Ill Ill .. I ... .I ..... IS APRX ALTITUDE OP: STAR 0 0 0 0 I s..z CONVERT (IS) TO MIL~ If HEC!SSARY ... I ... I I ... I ... "" " J I I 12 HAME Of STAR IBErEt.GEux 12 ll APRX AZIMUTH Of STAIII 0 0 . .:lSI 0 ll.. CONVIIIIT (13} TO MILS, If HICI.SSARY I ... I I ... I I ... II ... .. IS APRX ALTITUDE Of STAR. 0 0 0 I _,, 0 IS I I I " CONVERT (1S} TO :'fiLS. If HECESSAIIIY ... I ... ... ·-;: I I 12 NAME OP STAR tf~CrliRVS 12 ll APRX AZIMUTH OP STAR 0 0 0 .. R! I 1 I CONVERT (ll) TO MILS. If HECUSA.V I Ill I ... ... 0 ..ll "' I I IS APRX ALTITUDE Of STAR 0 0 0 l..z3 • I I I CONVERT (U} TO MILS, If MEC!SSARY ... Ill ... " I l I I ... " IS COMPUTER }(1.1#1( ICHECIIR hli IJFEe I SHEET I Of I SHEETS PREVIOUS EDITIONS OF THIS FORM ARE OeSOLETE. 6-21 Figure 123. Entries made on front of DA Form 6-21. AGO 10005A 197 TABLE TABLE ~1it TABLE II Ill DAY '· MIERI• M IIAY JUH JUL AUG ur OCT HOV oec ' TIME n .. L::::~ : '· DAY MONTH DP WATCH co.. I .... ,,. -TH ZOOO! DIAH MOMTH JAH Pel ArR .,,. lit• 24t• JO.. ,... ,. 40. 1 ·. 0" o• 211. 271. 100. 1st• z .. .. 2 101 U2 1St 1H 219 210 279 no 341 11 41 70 ,2 ..• 1 UST LONG I 1S A IS l 10> UJ 160 191 221 211 210 311 342 11 42 71 ., ,2 JO 72 41 I so 6 lOS 114 161 1t2 221 252 211 312 so 12 ., 6 I c 65 I ,.. ,,. U2 . ,., 222 211 212 ,, )46 u 44 73 ' 4 " 74 6 I 71 D 6 105 U6 1U 194 223 214 2U 316 Ul 14 " 6 tO l 71 7 104 " 1)7 114 1tJ 226 2U 214 liS ,.. IS .. 7J 7 7 101 , 90 .. I 107 U7 165 ,,. %21 254 211 JU U7 16 47 76 I 101 lSI 1U 197 226 257 216 317 ,.. 17 61 77 ' I 120 101 10 120 ' ,., us " 1H 211 ll7 ,,. 11 .. 71 10 lOt Ut U7 227 ' " 11 110 140 161 Itt 221 ,,. 211 319 JSO 19 so 7t 11 10 ISO I us us 12 111 141 169 200 229 260 219 l20 ,. 20 51 10 12 11 110 Jl1 21 S2 11 u v 12 111 • , 201 no 261 2H l21 L us 112 142 170 1t6 291 112 22 12 14 u.. 14 ,., 171 202 2)1 262 l22 , ' 110 1U 211 23 14 ll IS WIEST LONG IS 116 ,.. 172 203 232 2U 292 l2l ,., 14 226 z o• u 111 145 1n 204 2ll 264 2tl 326 ,.. 26 IS u u 1S 261321 ,.. 174 204 2U 265 294 ,,, 21 ,. II 17 u 1S 17 1U 256 57 11 0 10 11 117 " 147 ,,.. 205 ns 2U 2U l26 ,,. 26 B4 17 17 19 11 271 r 19 111 141 176 204 2l6 267 2t6 327 357 27 51 i' 19 " 261 197 321 lSI 21 59 20 r 211 Q 20 119 149 177 207 237 21 20 301 " 71 111 231 269 2tl llt ,, 2t " .. 21 120 ISO 201 10 90 22 21 JU • s to 22 121 111 179 209 2Jt 270 ,.. no 0 " ,, 210 240 271 300 ll1 1 31 62 91 2l 22 T 105 23 122 152 110 23 U6 u 120 26 123 ISJ 111 211 261 272 101 ll2 2 32 6l t2 .~ 112 212 242 272 102 ,, l ll u tl 25 v us 25 126 114 ,. 125 lSI 113 2U 242 274 IDS ll6 6 26 ... 65 ts ISO 26 ,, " " 27 l IU 27 126 116 ' • ' 114 214 264 275 306 ,, ,, .. 21 ·> y 110 21 127 157 liS 215 265 276 lOS ll6 • " 97 29121 151 114 216 266 277 304 ll7 7 l7 67 :tt ,,. ,. • J .\ . •.· ,,. ll .. 61 30 10 129 117 217 247 277 107 I 31 31 uo " 111 241 301 GIVEN : Time zone of area of operation. Latitude and longitude of station to nearest degree. Preselected local date of observation. Preselected watch time of observation to nearest hour . GUIDE: When observation i.! to be made at other than preselected watch time ((2) of computation), increase orientation angle ((11) of computation) 1 degree for each 4 minutes of elapsed time aft& the hour or decrease orientation angle 1 degree for each 4 minutes of time before the hour. Select stars between 20 and 45 degrees (60 degrees if a special eyepiece i.! available) above horizon and within 30 degrees of a 90-degree or 270-degree azimuth (east -west line) to use the altitu.de method. Select four stars for each schedule, tw o in the east and two others in the west. Read APRX AZIMUTH and APRX ALTITUDE of Slars fr om template of star id entifier to nearest degree. When using a mil-graduated insuumenr, convert APRX AZIMUTH and APRI ALTIT UDE to mils using table lli b of TM 6-230. LIMITATIONS:The altitude and hour-angle methods should not he used when the star i.! more than 60 degrees above horizon. RESULT : APRX AZIMUTH and APRX ALTITUDE for four schedules of four stars each at preselected watch times. Figure 124. Instructions fo r use of DA Form 6-21 . AGO 10005A 1 a. If Polaris is observed, the Polaris method 311. The form is designed for fifth-order workshould be used. For any other star (sun), a and combines all four methods of computation. quick inspection of the field data will determine The formulae to be used are shown on the backif the rate of change· in azimuth against the of the form. When used with the five-placerate of change in altitude is suitable for a comlogarithms in the back of the Army Ephemeris,putation involving altitude. If the rate is 1.0 the new form should reduce computation timeor less, one of the altitude methods should be by about one-half. The principal time-savingused. If the rate is 3.0 or less and a fifth-order feature of the form is that at least three setsazimuth only is desired, an altitude method of observations are meaned so that only onemay still be used. If the vertical angle is computation is required. The mean horizontalsuspected to be of poor quality, an altitude and vertical angles of the available sets aremethod should not be used. If time is accurate plotted against the mean time of observation toto 1 second and the rate is such that an altitude guard against erroneous field data. The demethod can be used, the altitude hour-angle parture from a straight line should not exceedmethod should be used. Avoid the altitude hour 1.0 mil. If, after plotting the observations,angle method if the approximate azimuth is three sets do not form a straight line withinwithin 200 mils of due east or west. In all other the prescribed tolerance, it will be necessarycases, the hour-angle method must be used. to compute all observed sets individually toAs the rate of change of azimuth against determine which are erroneous. DA Forms 6altitude starts to increase, it changes rapidly 10, 6-10a, and 6-11 are used for individualand the altitude method will fail completely if computation of three similar sets when thethe rate of change becomes too large. The computation of the mean values cannot be used. rate of change in azimuth against the rate of change in time increases more slowly, and a Use of these forms is discussed in paragraphs reasonable azimuth can always be obtained by 312 and 313. the hour-angle method. b. A rapid computation form (DA Form 308. Comparison of Methods2973) is shown in figure 125. The use of this Table III summarizes a comparison of theform will be discussed in paragraphs 310 and computation methods. Table Ill. Comparison of Computation Methods Element Polads Altitude-hour Altitude Hour-angle method angle meth od m ethod method Horizontal angle Required for all methods. Probable error of horizontal angle should be only a smallportion of allowed error.Vertical angle ___ _ Not required PE of observed vertical angle plus 1/ 300th Not requiredof astronomic refraction correction multiplied by rate of change in azimuth againstrate of change in altitude must not exceed 0.08 mil for 4th-order accuracy, 0.15 milfor 5th-order accuracy, or 1.0 mil for 1 :500 accuracy. Time -------------±1 min ±1 sec ±5 min ±1 sec (nearest day for stars) Temperature _____ _ Not required ±10• F ±to· F Not requiredLatitude _________ _ ±1• Not required ±15 sec ±15 sec(vertical angle (about 400 m) (about 400 m)may be used) I Longitude ________ ±15 min ±15 sec ±10 ±15 sec (about 20 km) (about 80 km) AGO 10005A 199 a. The accuracy requirements shown in table vertical angles. The rate of change in azimuth against the rate of change in altitude may be III for latitude and longitude are based on the obtained from the plates in appendix V which accuracy requirements for the astronomic comshow the areas of different rates. Rate of putation. It would be necessary to know the latitude and longitude within about 100 meters change of 0.5 is used for stars in area A, 1.0 or -+-2 seconds to compute convergence from is used for stars in area B, and 3.0 is used for geographic coordinates. The UTM coordinates, stars in area C. If the observations have if known within 100 meters, may be used for already been completed, a n inspection of the computing convergence. observed field data will quickly yield a more accurate value for the rate (the change in b. The statement pertaining to vertical angle horizontal angle divided by the change in applies to both the altitude and the altitude vertical angle). In most field problems, this hour-angle methods. The probable error of the inspection will only be of interest in deciding observed vertical angle is an estiq1ate of the whether it is necessar y to improve the azimuth surveyor based on t he instrument used and the determination by reobserving. The survey experience of the operator. Since the probable officer may quickly select the method of comerror is an estimate, %00t h of the vertical reputation from table III which will give the best answer from the data available. fraction need be added only for very small Section V. ASTRONOMIC COMPUTATIONS precomputed azimuth of Polaris for any hour 309. General angle. There is no requirement for accurate The artillery surveyor may use any one of time, and the star is easy to identify. The four methods to compute an azimuth by astroformula for using table 12 is given below the nomic observations.. The four methods are the table. DA Form 2973 is used for the Polaris Polaris method, the altitude hour-angle method, method. To compute azimuth by the Polaris the altitude method, and the hour-angle method. method, proceed as follows : The four methods are discussed in detail in a. Fill in the heading and transfer the obparagraphs 310 through 313. DA Form 6-11 served horizontal angle and time of observationor DA Form 2973 is used to compute azimuth for each set from the field notebook to theby the altitude method; DA Form 6-10, DA form. Mean the times of observations and mean Form 6-10a, or DA Form 2973, by the hour angle method. The computations for the Polaris the horizontal angles. Apply the watch correc tion (item 2) and the time zone correctionand altitude hour-angle methods can be per(item 3) and add algebraically to the meanformed only on DA form 2973. DA Forms 6-10, time to obtain the Greenwich mean time6-10a, and 6-11 are used when each set of ob servations must be computed individually. The (GMT) of observation and enter the GMT in item 4. Obtain the sidereal time of Oh Greenadvantage of individually computing each set wich from table 2 of the Army Ephemeris andis that a bad set which is not recognized as enter it in item 9; obtain the sidereal time bad before computation can be detected and rejected. The disadvantage is that individual correction for the GMT from table 4 of the Army Ephemeris and enter it in item 10. computations are time consuming. When DA Form 2973 is used, a bad set is detected by Convert the longitude of time units (hours, minutes, and seconds) by dividing the longitudeplotting the observed horizontal and vertical angles against the times of observations. The by 15. Enter this in item 11; use the plus sign ( +) if in west longitude and the minus signcomputations are then performed on the mean values of all good sets. This reduces the com(-) if in east longitude. Add items 4, 9, 10, and 11 to obtain the local sidereal time (LST). puting time by about one-half. Enter the LST in item 12. 31 0. The Polaris Method b. Enter table 12 of the Army Ephemeris with the LST and obtain b1,, the approximate Table 12 of the Army Ephemeris gives the AGO 10005 A 200 azimuth of Polaris in minutes of arc. Enter the Omit items 19 through 25 as the latitude is not bo in item 86. In the same column of table 12 used. The longitude must be converted to mils.of the Army Ephemeris, obtain b, and b", the Use table 5 in the Army Ephemeris and itemstwo small corrections for latitude and the 26 through 33 on the form for the conversion. month of the year respectively. Enter b, and b" The declination is required in mils. If the sunin items 87 and 88, respectively. The negative is observed, use table 2 in the Army Ephemerissign is used in the table to indicate that azi and items 37 through 47 for the interpolation.muth is west of north. Enter the sum of bo, b" If a star is observed, use table lOb in the Armyand b:! in item 89. Place the log of this sum in Ephemeris. Enter the log cosine of the declinaitem 90. Enter the log of the conversion factor tion m item 81. If the sun is observed, use itemsfor minutes of arc to mils in item 91. Enter the 5 through 8 to obtain the Greenwich hour anglecolog cosine of the latitude in item 92. Enter (GHA). The 12-hour correction required tothe sum of the logs in item 93. Enter the antilog change to hour angle is introduced in item 8.of item 93, which i's the azimuth of Polaris in To convert the Greenwich hour angle to mils, mils, in item 94, retaining the sign of item 86. complete items 13 through 18 by entering tableEnter 6,400 mils plus the azimuth of Polaris 5 of the Army Ephemeris, using item 8 as an (item 94) in item 95. Enter the mean argument. Transfer the longitude in mils fromhorizontal angles in item 96. Subtract the mean item 33 to item 16 and add items 13 through 16horizontal angle from item 95 to obtain the algebraically to obtain the local hour angleazimuth to the azimuth mark. Enter the azi(LHA) in mils. Enter the local hour angle inmuth to the azimuth mark in item 97. A sample item 17. The local hour angle in mils is •·t"computation is shown in figure 125. in t he formula and should be subtracted from6,400 if it is greater than 3,200 mils. Enter the 311. The Altitude-Hour Angle Method fin al result in item 18. Obtain the log sine of This method of computing azimuth is new to item 18 and enter it in item 80. Figure 126 the artillery. It is a faster method than either shows computations by the altitude hour-anglemethod, using the sun. the altitude or the hour-angle method. Whenusing this method, one cannot determine the b. If a star is observed, the procedure forquadrant in which the star lies, and this method determining the local hour angle is slightlyshould not be used for observing on due east or different. Use items 9 through 12 to determine due west stars. The approximate azimuth must the GHA instead of items 5 through 8. Obtainbe accurate enough to determine the quadrant. the s idereal time for 0h of the date in table 2DA Form 2973 is used for the altitude hourof the Army Ephemeris and enter it in item 9.angle method. To compute azimuth by the Obtain the correction to the mean time interval altitude hour-angle method, proceed as follows: for t he Greenwich time from table 4 of theArmy Ephemeris and enter it in item 10. a. Fill in the heading on the form and transObtain the right ascension for the star fromfer the mean observed data for each set from the field notebook to the form. Plot the mean table 10 of the Army Ephemeris and enter it horizontal angles for the sets against the in item 11. Add item 4 and items 9 through 11 algebraically and enter the sum, which is the mean times of observations. Reject any set GHA for the star, in item 12. The procedure which does not plot within 1.0 mil of a straight for converting the GHA to mils when a star isline. Plot the vertical angles in the same observed is the same as that when the sun ismanner and use the same rejection limit. Mean observed except that items 13 through 15 are the remaining sets to obtain one mean time ofobservation, one mean horizontal angle, and used for a star. Correct the mean observed one mean vertical angle. Correct the mean vertical angle for refraction. Record the truevertical angle in item 36. Obtain the colog observed vertical angle for parallax and recosine and enter it in item 82. fraction in items 34 and 35. Record the truevertical angle in item 36. Obtain the colog c. The altitude hour-angle method block nowcosine and enter in item 82. Compute the contains all data necessary for the computation. Greenwich mean time, using items 1 through 4. For fifth-order or lower accuracy, some time AGO 10005A 201 sTu-Po.t.BR!:s Irtri'H ORDER ASTI.OHOHIC .UlKUTH COKPUTA.t'ION .um IIU)!Ill I 0 LOCAL ~~PPROX. Al 42'1/ STATION SO 2b0 TEMP TO AZ MJC. n..,.. 24 JVIV ~=Tll WT VERTICAL WATCH Til« HORIZONTAL Flll.D DA'IA or n...uv ur.u '. S!T NO . I 22 1 o31o;c 2117 I 0 + t-u, 13 + t.l"' 1_-t SI!T NO. 2. 22 106 ' o :ZII 7 I 2 +,{,lt,l5" SET NO , .3 22 1o9 1o6 2117 I -+ I I I I StT NO . I I I I SET NO. I I I I S!T NO . SUH t.6 1 18 112. t:.3S/ I h r /.J'f.'fl Z ,2 2 I p~I01-2 { I 7 I z +-" { 6 I + 2 = ~~~ ~24 1 o+ 'zs LATTITuot ~ 3 of ' 3'! l+si3• =IoN ~ I 3 ~~;:_ w•·~~ b 1oo 1oo 19 ~~RE~= TENS or .5331 33 3~ :~~~yo~· ~"!'• ..\ I I 1 t o 1 32 2o I ~~;;"...=UNITS OP 71 I II 36 (IJ+(34J+(3~J·b \ I / I HI!.All 4 i o~f;\ ur I ! \ 18 .... • 7-I \))32 ~~.~lj2~UH I I \ ·1~•... .., ,:..., 24~ AM U~o OOL!j;,.ft' ~!-~~"::'};I~~~~~~ "~"~;'l.~ ABtJLA.R H!TMOD USE LOII::IT1JD! +)6HOU T1W< 24h (-) LOCAL OAT! +1 IN D!GU!S ._ IS V/SIGN(-)lF LOHCI(·) (+) LOCAL OAT! -1 """' V!STC+l IF !'.AliT lP (I) IS : -.1!l...!L .... {IF 17) IS : (18) IS : ( -)OR 0 TO 32 0010 REPEAT ( II)H ( -)OR(+) AliD L!SS T1W< 12h (I) + l2b (I) -12b 320011 TO 6400!1 640011 • (17) SIGN (·) l«lU T1W1 640011 ( 17)-6400!1 SIGN (+)+ AliD MORE T1W< 12h HOlTR ANCLE HETliOD ALTiniD! MrrHOD ALTITUDE -HOUR AtCU HEntOD ' --+..!!80~LOG SIN ( 18) F4'"f8..!.1u2c._1Jfll"'-',8\iiii'i'ii''-'-•...:,_._.,-l____r7.:.2-f-!c"'oLOG=...:c,o,s...:<>.:6:.:.7lL....-+-,Ir-___,_,1:.:.7+'1~noo<.-Tu u 12 +-oI z1 11 h nMG LST02> +-o l 5" ~7 COLOG COS (~ I ) I n coLOG cos c6a> toe cos 10' I •• r 8• U±iJlliJ....8'-t-r-2<::....!.4____,1r'--l ~8 LOG SIN CS2l I 74 LOG cos {71) I 90 LOG U9l 1 1 3'1~20~9 REPEAT ~5 I 7 91 LOG FACTOR 9 I 471 7 0 I 76 72}+(73}+(74}+(7~ I l6o Inn< 1Bl+t59l I 77 1/2 (76) I 92 . COLOC cos (2~) 0 I 0 6+91> I 78 AJrrlLOG COS (77) ! 93 (.90}+(tl)•+(92.) 01 "!!>2. 7{, I •-(84) IS 8!AR1HC AHCL! US! APPROX AZ lHtmt TO AZ IKUTH KARX COHPt.ri'ER 95 A ...... AZ TO DET!RI11Nl. VALUE Or A ...... Z TO ITA~ • A WHEN STAR IS 1M !ASTt'J. • 6400 -A WHEN STAt IS IN V!ST CHECIER lJID 6400 IF (!15) IS Lilli TIWI (96) 97 (9~)-(96)•~-:;;_ 42"11 1~ DA FORM 2973. I Moy 65 l!'igure 125. DA Form 2973 showing computations by the Polaris method. AGO 10005 A 202 STU-5ur _' __ PlrTH ORDER ASTI.OMOHIC .Unn.rrH COHPlTUTION ~L 24 !u,v VTnn llATJ S!T 110 . I SI':T 110 . ;2 SET NO 3 SET NO. SET NO . I I S!T 110 . I I I I SUM 28 1 .28 1 /0 // 305IZ 2~ · ~~ 1 IO I 'n'l.. ,~F~~TION - FAST -• 24 0 -r Z1 LAT"fiTUD£ S .rr J I l'hT 1,_ .1 J.A.Il1L lzz S ~~:T~;T~~:-2° 0 I Z 1e>r 21 ~~rr~TENSOF $18'f 3 7 ~::.r ~:/:S6~N 9/J/7100 6 ~~A~::/31AT c Kr I ~ I I oS 22 I ~~~~ Ullt Ts or .z I 6 7 38 :.::.r o =,KIM IN ..3 3 I oo 1 <4>·~~·<6>· ~ /5' 3t 1 27 2 3 1 ~~~~=TEifS oF lzo 39 cH> +oa> '1 331oo 8 -• cHA ~ 3 1 .31 !27 2 4 ~~~~ UIIITS oF I04 40 ~~~T=-r!~~ ~t=> l35" 9 ~~D~I~T~~T~, 2 + I I 2 S ~~~9~1~RU( 24 ~/"I 2'f 41 L0C (39) 2l '16'JJ'f'Z 10 1 ~~~:;"1011 TO ( g ) + I LONCITUDE &1 lfi '21-•:ti' 42 L0C ( 40) Cj' I 544068 u • • • ~ I I 2 6 I::!LS""~~~R!DS I 43 = CONSTAI+J:.>~i~~;01 : 1 1 2 1 ~asug m s o F 1r,.ooloo 44 (41)+ ( 42)+ ( 43) '71 3~5"SSF I] m~~F.J~~~~~R I~ f?oo1oo 21 ~~~REgUlltTS OF J4:Z 122 4S ~E1~N~~~) 9 1 .z3 141 ~~OF GilA IN 1':' /.371 7~ 29 ~::rri; r ur 5 1'13 46 ~ DA~ ~;A~Ll0;) :' 4-1 '-1 4-4 :i~OF CRAIN ~ .zl OO 30 ~~~= Ul) IS LIU TIIAII (96) 97 ( 95)-(96)·~-:;;_ 42921 IDA FORM 2973. 1 May 65 Figure 126. DA Form 2973 showing computations by thealtitude-hour angie method using the sun. AGO 10005A 203 sru ... DEN£ 8 FirTH ORDER ASn.owoKIC .UlKUTH COKPUTA.TIOM .um IIUIIIU t. .V LOCAL s-1 AZIKU'm ~~PPROX . AZ z / STATION S p Zt<,o TEKP f/3 °P TO AZ I« ·~ 24 J, ..."" w VERTICAL WATCH TII1! HORIZOtn'AL nF n..uv AJ«:U: FinD nATA + e2S.4 SET NO . I 23 1 11 1 17 314'-1 8 S!T NO. z 23 1 14 1 11 .3!4X'1 2 + 8.H13 SET NO 3 ZB 1 1g. 1o1 .3t5d 0 +1'+,1 + I I I I S!T NO. I I StT NO I I I I I I SET NO . SUM {,'f 14:3 1:3,;. 944-510 +25'01>11 I HEAII 23!14131 3;4813 83514 WATCH l.z5' 2 CORA :~: ~24 1CJ4 1:za !.ATTITUDE ~~~..~~ TeNS OF I '~~~. "'··;=~ 6 1 oo1oo 19 lllU N UNITS OP 4 , ~~i~\ I SECONDS 39 8 .. • CHA : I I 24 ~~.:,; UNITS OF I 04-40 ~~;!T~~~~ ";. I I I 6 I 8416)8 I(41)+(42)+(4)) A.......... I USE SICN 40 I"'' ~• •• ~ "" I 14 ~:'..:0' CHAIN i~ ZZI<> I {>7 29 ~~: ,.., ur 5 193 46 CW DAn TAIL! 2 • " ~~OF CRAIN ,~ /1 / 05'4- I 67 RlP!AT 06 I 8J (~)+(81)+(82) 51 49 • (50 ~NTll.<><; "" [OJ)• 52 (49 • 50 I 68 RlPEAT(25);;;;;.;.;;: I 84 ~~~~~· !NT!R IN 1 85 ~A ,.. 69 (66)+(67)+(68) I 1 53 COLOC SIN 51 I l7o 1" ''"' • • • POUltS TABUU.R METHOD 54 t.~·~(~5·~>~·~(~55~)~-~r--------t'~2-rC~O~UC~C~O~S~(~6~ 7)~+-.-I--------~8~7+1~~·--T·IU: 12 I ll!IC LST(I2) I 57 couc cos (51) I 7J coux cos (68) I 88 2 58 uc SIN (52} I 74 uc cos (]0\ I •• ,..... 107'1< ••, II 7 uc cos (71 I 90 Ur (89\ 59 RlP!AT 55\ I 91 UC FACTOR 9 I 471 1 , 0 '"··""" ""' I 76 72)+(73)+(74)+(75 I trn'IUX: TAN (60) + I I 92 coux cos (25) I 61 lust SICN (51 77 1/2 (76) , I 62 ~I~•T'(';2),., ~ 1 78 ANTIUC cos (77) ! 9J (90)+ (II)•+ (92.) I I *........ (84) lS BlARIIC AJCU US! APPROI AZIH1JI'H TO AZIKlTnl KAU CCHPLrn:R AZ TO D!T!RKIKl VALUE OF A 95 A*****'* ...... Z TO ITAR • A WHEN STAR IS IN lAST CKECICER Z • 6400 -A WHEN STAR IS IN W!ST lDD ~IP (U) IS LIM 'l'IWI (96) 97 (95)·(96)-~; 42911 9 DA FORM 2973 , 1 Moy 65 Figure 127. DA Fo1·m 2973 showing computations by the altitudehour angle method using the star Deneb. AGO 10005A 204 ---------------------------------------------------------------~ will be saved if the five-place logs in table 14 in p = polar distance of the star (sun) ;the Army Ephemeris are used. For fifth-orderaccuracy, it is better to make a rough interLat = latitude of the station; polation to 0.1 mil. The colog cosine in item 82 h = true altitude of the sun (star). is obtained by subtracting the log cosine from DA Form 6-1 is used to determine the10.0. Each digit is mentally subtracted from 9 a tronomic azimuth of the sun (star) byand the result is entered in item 82. The sum solving this formula through the use of of the two log sines and the colog cosine is logarithms. Figure 128 shows computations byentered in item 83. The angle the sine of which the altitude method, using the sun and theis equal to this sum is the bearing angle and sample field notes in figure 118. Figure 129is entered in item 84. The bearing angle is "B" shows computations by the altitude method,in the formula. The bearing angle may be using Deneb, and the sample field notes irieither east or west from either the north or the figure 119. To solve the formula by use of DAsouth pole. By inspection of the approximate F rm 6-11, proceed as follows:azimuth, the proper quadrant may be determined unless the azimuth is too near due east (1) Enter the station data which includes: (a) Latitude of the station. or west. The bearing angle "B" is then reduced (b) Longitude of the station. to an azimuth ''A" (by subtracting it from or (c) Approximate azimuth to the azi adding it to 3,200 or subtracting if from 6,400, as required) and entered in item 85. Figure muth mark. (d) Local data. 127 shows computations by the altitude hour angle method, using the star Deneb. ( e) Narne or description of the azimuthmark. (f) Name of occupied station. 312. The Altitude Method (g) Temperature. Computations of astronomic azimuth by the (h) Name of the computer. altitude method can be performed on either DA (i) Name of the checker. (j) Notebook reference. Form 6-11 or on the new rapid computationform, DA Form 2973. DA Form 6-11 is used (k) Area name (if available) of the to compute the sets individually and to compare area in which the fieldwork was completed. the resulting azimuths to determine if a set contains erroneous data. DA Form 2973 is (l) A sketch of the survey involved. used to compare the data from all sets (2) From the field notebook, enter the fol graphically to detect erroneous field data; the ing field data : computations are then made by using the mean (a) On line 1, enter the mean watch data of all remaining sets. time of observation. (b) On line 2, enter the watch correc a. Instructions for the use of DA Form 6-11 tion. are on the back of the form ; the portion labeled (c) On line 7, enter the mean vertical "limitations" is obsolete. Several formulas can angle measured to the sun (star). be used for the solution of a spherical triangle (d) On line 36, enter the mean horizon the three sides of which are known; however, tal angle measured from the azi the formula selected for artillery survey use muth mark to the sun (star). is: (3) Use lines 1 through 6 to compute the Cos lf..! A =/Cos s Cos (s-p) Greenwich mean time of observation. ~ Cos Lat Cos h GMT is required as an argument for entering table 2 in the Army Ephe Where A = astronomic azimuth of the sun meris to obtain the declination of the(star) measured east or west of sun. This computation may be omitthe observer's meridian; ted if the celestial body is a star.s = lf.2 sum of polar distance, latitude, The Greenwich date may differ fromand true altitude. the local date. Follow the rules at the AGO Hl005A 205 i~ TABLE NRS REFER TO TM 6· 300· 19~ ~¥~R0~AME SUICOMPUTATIOH-ASTROHOMIC AZIMUTH OY ALTITUDE METHOD, SUH OR STAR ANO NR ( TABLE 9 ) CO MPUTER > Cl 0.... Figure 128. DA Form 6-11 showing computations by the altitude m ethod, u sing the sun. 000 "'> L .-~ > cCl .... 00 >"'0 ..., 0.... AUXILIARY COMPUTATION FOR APPARENT DECLINATION OF SUNAT GREEI!IWICH DATE AND GMT GIVEN: Time zone of area of operation.FIELD DATA:Latitude and longitude of station.Approximate azimuth to azimuth mark and to sun or star (sketch).Sun or name(o) and number(s) of selected star(s).Local date of observation.Temperature at time of observation. Mean watch time of observation and watch correction. Horizontal clockwise angle from azimuth mark to sun.Observed altitude of (vertical angle to) sun or star.GUIDE: Enter observed field data in block marked. t:::::=:J When using a mil-graduated instrument,- a. (7) through (22) of computation are computeo using hundredth·mll values. b. (6) through (14) of AUXILIARY COMPUTATION are computed using hundredthmil values. c. (2) through (9) and (11) through (17) of CONVERSION TO MILS COMPUTATION are computed using hundredth-mil values. d. (23) through (37) of computation Are computed using tenth-mil values.Value in (37) should be about equal to approximate azimuth to azimuth mark.Continue computations using DA Form 6-20 to obtain the UTM grid azimuth. LIMITATIONS: This form should not be used when accuracies greater than fourth-order are required. The altitude method should not be used when the sun or star Is- a. Less tha n 20 degrees or more C'l0 .... 00 0>- TJ.BLE NRS REFER TO TM 6 . 300. 19_ D~ebCOMPUTATIOH·ASTROHOMIC AZIMUTH OY ALTITUDE METHOD, SUH OR STAR _ ITATIOH F igure 129. DA F orm 6-11 showing computations by the altitude method, using the star D eneb. ..... 0C)> 0 0 0 >"' AUXILIARY COMPUTATION FOR APPARENT DECLINATION OF SUN AT GREEr!WICH DATE AND GMT B~ SfTNit, UTMit __ GIVEN: I IGIIIU.P OF 12.0 39 (37) + {38) Ci'..3 :f I00 a *" • GKA '!: 1 I 24 ~~~~ UNITS OF I 04 40 ~i~T=a:.='i'r-1 1.35 1 9 1 ~~n~~T~~r~ , . + I 25 ~;. i~,';"~RUC24 01tb 1Z•hr LOG (39) 2. 19.h t19P:Z 10 ~~~;riCH TO ( 9 ) + I I LOICITUDE <§J 9J' · :2.-4, 1 1R 42 LOG (40) 9T.54-40~9 • • • ~ I t 26 I ~LSJ'IP;:,.~R!OS ! 4) ux; CONSTAHT 6 I 841638 (4}+(9)+(10)+(11 + 1 HILS IN TENS OF I 12 • ""' n• I..::4~7)c_--l-~T~----I 50 1/2 (47) I 66 (64) + ;65) -p +I I tr3 179 82 COLOG cos (36) T l 49 + (50 67 R£PEAT I (361. +-f?7I I o.z 8) (80)+(81)+ ( 82 ) 1 52 (49) -(50) I I 68 R£PEAT(2S)SOn o" ,••• • ~ I ."? 3.~ -5'2 POUlllS TABULAR HEniOO 55 I LOG COT 48) I 11 10 -66 + I 5'1 1 7.3 86Jbo ~~~~n I 56 SJ) + (54) + (55) I 72 COLOGC0S(67) 0] /X'3003 87 I lnnooTUUI21----~~-I 57 COLOC COS {51) I n coLOG cos (68> o I of?+ R+'i 88 2 n~~; LSTII2l 1 58 LOC SIN 52 I 74 t«. r.ns 170\ l914-t:J95.3-4 89 '18H>I8lli.Uio.IIL"'-+~--~--1 59 REPEAT 55 I I 751t«.cosml 91 q'1S!6'-19o~u.<8o\ I 76 72)+(73)+(74)+(7511'7'1 &; 7.2 5 52 91 LOG FACTOR HTILOG TAN (60) + I 61 USE SICN 51 l 71 1/2 (76) ql;3 ~2. 7~ 92 COLOG COS (25) I 78 AliT I LOG COS ( 77) 93 (90)+(91) + ( 92) I I 2 x (18) • A79 1....... ,. ,.~, I ~ - *......,(84) IS BEA.RllC A!CU US!. APPR.OX C()o(plTfER AZIH\ml TO AZIH\ml KARX AZ TO DET!RKIN! VALliE OF A 95 A• lt.t.••;Tz Z TO ITAk • ~vHOklZO!rrAL CHECKER A WK!N STAR IS IN U.ST 96 .37;0;K'14 13~ ail • 6400 -A WHEN STAI. IS IN 1/tST D ~IP (~S) It 1.118 '1'lWI ( M) 97 (95)-(96)·~ ~ 42911? DA FORM 2973, I Ma y 65 Figure 180. DA Form 2978 showing computations by the altitude method, using the sun. 211 STAI-DENEB Plrnt ORDEI\ ASTI.OMOHIC .UIM1!I'H COKPUTA.TION .um IIUMU• to a TEHP 3.3 ., ~L 24-J1.1.N "sl ~~nt WT ~~~P~~XKKAZ 2'1/ STATION so .2(,0 VERTICALWATCH TYKE HORtZOtn'AL ?lll.D DATA I n• nLURV ' ""'-" + Si'7•.t;l 4 SET NO . 1 23 1 1/ 1/7 3/4-1.,1 9 +li'341.3 SET NO . 2. ZB 1 t4 1 11 .-=>,t4-fl. .z + 84(:,1 4 23 1 08 1n 4 .:J/-?01 0 SET NO 3 1 I S" NO. 1 I I l SET NO SET NO . 2.5'o6 I 1 SUI1 6<7 !43 :3..( 94-1-~ 0 li'.~5 ' -4 I K!AN 7 3 1 /4-13 .3!48T3 lzs 2 I~~!~" ~~ ~ ~24 1 04!.2~ 1.\TTITUDE \.f Hll.S IN TENS OF ~1 oo1 o~ 19 DECREES 5"33 r33 35 1 b' 18 1.5'1 20 I~~;;oRE~= UNITS OP 7 I I 1 I 36 ( 1)+(34)+(35)• b -t-5'351 JS NO . OP HRS INHILS IN TENS OF I I 21 MINUTE< 8 I 8&f 37 GHT (4) • 60 I HlLS IN UNITS OF 1 I I 22 IMIN\TfES ..z 1~7 J8 ( 4)+ (5)+ (6) -+ I 23 I~~~.;; TENS OF lzo 39 (37) + (38) I 7 r. AT • ' I I I 24 =~~~ UNITS OF I o4-40 8 *'* • CHA LAT IN HILS T I I 25 SUI1 ( 19 ) THRU(24 ~I~ I :Z4 4t LOG (39) I LOG ( 40) 10 ~~~;r!~ TO (9) + I LOHC ITUDE I + I I 4) LOC CONSTAHT 6 841638 I ... T I ~.... (IF (17) IS , (18) 15, .. IP (7) 15 , ( ·)OR 0 TO 32 0011 REPEAT (17)(·)OR(+) ANll IZSS T1IAN 12b (7) + 12b 12b 320011 TO 640011 640011 • (17) SIGN (·) IClO! T1IAl< "-0011 (17)·640o,i SIGN (+) + ANll HORE ntAN 12h (7) • HOU1l AtCLE MEntOD ALTtnii:Jt: H!THOD ALTITUDE -HOUR ANGLE METHOD + I 64 t 600 -oo KILS 1 c. no~ o o eo toe siN n8> T .... 112 (18 NORTH + I 8 ao2 17 1 81 =cos <•7> T 49 1/2 (25)SOiml • 65 I~J~!~IG• + I p + 7971 2"1 8 2 COLOC cos ( 36) I 50 1/2 (47) 66 (64) + (65) + I 67 REPEAT ()6) + g 35 1I 5 83 ( 80)+(81)+(82) I 51 {49) + (50) I I 52 ( 49) • (50) I 69 (66)+(67)+(68) ':' :274-.1?16fl 85 ...... E";!~ IN 53 COLOC SIN (51) I ~ I I 24-1 34-POURIS TAIUUR HEntOO [li LOG COS C521 17 0 112 • ., -< I 166 + 3271o.s a6 o I~~~~. I 11 101 • 55 LOG COT C48 I Of I" (ptJ5'4 87 1 inOM TULE 12 1-----1-----1 56 53) + (54) + (55) 72 COLOC COS (67) 57 COLOC COS ( 51) I 7l cotoc cos ( 68) 0 I 0 8 4.51-'1 88 2 llu~ LSTI12\ 1 58 LOG SIN (52 ) I 74 !toe cos 110\ .,.1 tC.S:-?4?91 •• 10< •I•U±L8~_u_·'-+---.---l--l 1 I n = cos m1 r1<~ 7 7 2.zs190 kLr: (891 59 REPEAT C55 l I 76 72)+(73)+(74)+(751/91 11III 5S7 91 LOG FACTOR 9 I 471 1 oo I" ,,. ·""' INTILOC TAN ( 60) + I 77 1/2 (76) 9l740779 92 COLOC COS (25) 61 lust SYCN 511 I I C 771 s"Jr!" 9) (9o>+ (78 ) • A I I 79 1...,... TN 19\\ *****(84) IS BEARllC AlCU US! o\PPROI 1--~-A::Z~I~Klmi~~Tc:::O..:_A~Z~IKlmi~:....:::MA:":RX~-r---1 CCtQtlli'ER AZ TO DE'ni.KlM! VALU! OP A 95 A ........ 743 '1 1 11 Z TO IT.U • A WHE!f STAR IS IN !AST - Jo.Z TO Z • 6400 • A II!IE N STAR IS IN W!ST CKECU:R W ~IP (n) IS LIM rtWI (ti) 97 (95)·(96)• A2 HI( 429115 DA FORM 2973, 1 May 65 Figure 131. DA Form 2973 showing computations by the altitude method, using the star Deneb. A GO 10005A 212 -_____ ___ _ _______ _ _____ _ _j (2) From the field notebook, enter the fol-of a spherical triangle when two sides and thelowing field data for each set: included angle are known are: (a) Mean watch time of observation. (b) Mean horizontal angle. tan V:! (A+q) = cos lh (Lat-Dec) cot l/2 t (c) Mean vertical angle. sin lf2 (Lat+Dec) (3) Add the mean values of the sets, tan 1f.2 (A-q) = sin tj :! (Lat-Dec) cot lj :! tdivide the sum by the number of sets cos % (Lat+Dec) used, and enter the mean of each value where A = astronomic azimuth of the sun in item 1. (star) measured east or west of (4) Us e items 1 through 4 to compute the the observer's meridian;GMT and Greenwich date. GMT is q =parallactic angle (cancels out innot required when observing a star. computations); (5) Ignore or cross out items 5 thTough Lat -latitude of the station;18, as they are not required when Dec =declination of the star or appar computing by the altitude method. rent declination of the sun; (6) In items 19 thr·ough 25, convert the t =hour angle (less than 12~>) of the latitude from degrees, minutes, and sun (star). seconds to mils. Figure 132 shows a computation on DA Form (7) Ignore or· cross out items 26 thr·ough 6-10 by the hour-angle method, using the sun33, as they are not required when and the sample field notes in figure 118. Figcomputing by the altitude method. ure 133 shows computations on DA Form 6 (8) In items 34 through 36, determine the 10a, using the star Deneb and the sample fieldvalue of h. notes in figure 119. To solve the formulas byuse of DA Forms 6-10 and 6-10a, proceed as (9) In items 37 thr-ough 47, determine the follows: apparent declination of the sun. These items are used only when observing (1) Enter the station data. The same in the sun and may be ignored or crossed formation is required as on DA Form out when observing a star. 6-11 (para 312a(l)) except that thetemperature is not required. (10) Use items 64 through 79 to computethe value of A. Note that cologs, as (2) From the field notebook, enter the folwell as logarithms, are used. Cologs lowing field data:are determined by subtracting the log(a) On line 1, enter the mean watcharithms from 10.0. time of observation. (b) On line 2, enter the watch correc (11) Use ttems 95 thr·ough 97 to compute tion. the final azimuth from the occupied station to the azimuth mark by sub(c) On line 40, enter the mean horizontal angle measured from the azi tracting the mean horizontal angle from the azimuth of the sun or star. muth mark to the sun (star). (3) Use lines 1 through 6 to compute the 313. The Hour-Angle Method Greenwich mean time of observation. Computations of astronomic azimuth by the Use the same procedures as discussedhour-angle method can be performed on DA in paragraph 312a(3). Note the valueof line 5 and follow the rules at the Form 6-10 when the sun is observed, DA Form bottom of the form. 6-10a when a star is observed, or DA Form The Greenwichdate is used to enter table 2 or table 2973 when either the sun or a star is observed. 10 of the Army Ephemeris. a. Instructions for the use of DA Forms 6-10 (4) Use lines 6 through 16 to determine and 6-10a are on the back of the forms. The the value of % t, or the hour angleformulas used on these forms for the solution of the sun (star). The procedure for AGO !0005A 213 ..., .. TABLE NRS REFER TO TM 6-300. 19.£5_ SUN COMPUTATION · ASTRONOM~C AZIMUTH BY HOUR· ANGLE METHOD, SUN LOCAL OATE+I DA'I' DA P REVIOU S EDITIO N OF THIS FORM IS OBSOLETE . 6-10 FORM 1 J.A N 56 > C'l DA Form 6-10 showing computations by the hour-angle method, using the sun. 0 Figure 132. ~ 0 0 0"'> ~ > - 8 0 g0 > CONVERSION COMPUTATION (TABLE 5) HOURS, MINUTES ANO SECONOS (TIME ) TO OEGREES, MINUTES ANO SECONOS OR MILS (AR C) UT 1011 ...!. UT I'll _g_ \[ l Mit ___}____ GIVEN:till Of CO•"UT ATIO"' OfGIUI~ 011 "tLS JH HOUIIS Of Ill 3 • 28" 15' ~ · : ~1~ 20' ~· y~ 41 ' Time zone of area of operation. ' BooOO eoo oo FIELD DATA: OfC:Oit fU ,uoO ltlfOUTU Cfl • ILl Iff ,.I..UTU Of Ill BOO 00 ' Latitude and longitude of station. ' ' " llCOHOS Of Il l 124 44 137 78 l.51 ll ' Approximate azimuth to azimuth mark. I + + I U 1 ll l¥ >·· 3 48 . Local date of observation. II I,.UTU AN D s~COOIDS 011 •ILl {fNf(ilt IH IIJI 0 H ,.01'11) ' 925 55 : 9~9 26 9'5.4 Mean watch time of observation and watch correction to nearest second . 'i9 . Horizontal clockwise angle from azimuth mark to sun. CONVERSION TO MILS COMPUTATION (USE TABLE Ill b OF TM 6-230) GUIDE: Enter observed fi e ld data in block marked. c=1 I,.OHGitUOf (fiiO• fltOHT Of fOil •) When using a mil-graduated instrument,-- I 98 24 ' 18' 10 · (,~~!~~~' Of rou) ~4' ~9, rio IN H UHOII(OS O f : 48" {2) through {5) of CXJNVERSlON CXJMPUTATION are computed using hundredth- OEC.IIlf\ OJ t il r1o '"' Tl"'' or l O(C.IlU Or 11~1 mil values. .-. '" tl..~ o r " s :33 ! ~3 a. OlC.II(UOr Il l lf'l tOiUHIHOr 16 00 ! 00 D :'r~•~:~'~For,• • :71 ~ ll b . {2) through (9 ) and (11) through (1 7 ) of CONVERSION TO MILS CXJMPUTATION . OlC.IIlUOr Ill lf'ltHT(Hli;)F are computed using hundredth-mil values. rlt IPI l(H' o r 1 42 ! 22 8 ~89 c . ll "IHUT(liOrii OI Mll'tUTUOF Ill fll tPI UHi l\ Or {12) through {24) of computation are computed using hundredth-mil values.I rlt IPI UOiiHOF 5 . 93 " 2 . 67 d. {6) through {14) of AUXILIARY COMPUTATION are computed using hundredth· M\HUl lli OFI\01 6 OIIH UT UOr llf 1 ~19 II U CQHO\OF flGI mil values. ill IH Tl101i O F rJ. IPI l[Hli O J ~ 207 uco "o' OF 111 ~ 5 .., ... u .. •nor e . {25 ) thr ough (41) of co mputation are computed using tenth -mil values. 16 StC0 H01i OF { IGI • lil t.< U"IHOF ! 4 Value in {41) should be about equal to approximate azimuth t o azimuth mark. Hc~osor rn li U"' Or Ill\ TtUI OUC.H !161 4 6 16 : 24 Continue computations using DA Form 6 -20 to obtain the UTM grid azimuth. 9 :;!"'Fo:o~'~ :~~o~;~~·~o•(:!l."~f ' I)) 17 17 [~:~(0:1;.1 1:;:: :.~~HT] LIMITATIONS: 49 . 4' ) AUXILIARY COMPUTATION FOR APPARENT DECLINATION OF SUH This form is not to be used when accuracies greater than fourth·order are required. The hour-angle method should not be used when the sun is more than 60 degreesI AT GREENWICH DATE AND GMT above horizon.I•'• UTH _ __1_ RESULTS: I UT l'tt (( 2 Ul Pill --'--A value of astronomic aztmuth for each set of observations. 1 C. lltl WW ICH O•f( (1 6) OF COMPUT•1I011) 24 June 64 24 June 6'5 FORMULAS: 24 June 6'5 , C. •T [1't0UIIl u24 19. 3'i7 10 WU M8( 11 '"'"YIWC. LOC. CIOJ 4451 ;HC0W01 01 MI Ll 0, CH.W(;( " . 231 .. ···• .231 . 231 } t =hour ongle {less than 1~} of sun. 41"~4R(fOII ... 16 44 ll .. .. •Ltolii.IC liUIII (IJI ••o Ill) · I~: 2~ ~.;.: 2'1 !"" ~ 2'1 11 fWtliiiWIIIIOI Cl -0 00 L 0 >- CONVERSION COMPUTATION (TABLE S) HOURS, MINUTES AND SECONDS (TIME) TO DEGREES, MINUTES AND SECONDS OR MILS ( ARC) GIVEN: Time zone of area of operation. FIELD DATA: Latitude and longitude of starion. Approximate azimuth to azimuth mar k . Name(s) and number(s) of selected star(s). Local date of observation. Mean watch time of observation and watch correction to nearest second. Horizontal cloct COMPUTATION· ASTRONOMIC AZIMUTH BY HOUR· ANGLE METHOD, STAR TABLE NRS REFER TO Tlol 6· 300. 19~ STAR NAME DenebANDNR (TABLE9) 68 LATITUDE -~T· --~~ Hl L.OMC ITUDI! OI 39~ 8 0 TTAPRX A Z 0' ST"'TIOH 34 1 "' a. Of STATION 98 24 '; 18 4291 '''"'24 June 1965 I"'""'" 'Wa.ter Tank SUfiOH SD 260 w TO A Z MIC DATE IIIAIUt -..-.. - Sf.TMR SUNil Sf:THR _i_ Sf:TNA_ 1 _ Pll m l 1 21 I UP!AT (17) ~ ,11 1 ,17 23 ·:14 2 m; u . 2.3 •: 18mP4 'a 1 ~ 616 :24 616 2.4 REPEAT (II)WITH OPPOSITE SI CI'I ~~ f!?4 28 ~ 28 ~4 ~8 2 1 22 11 ~ 802 :71 ALCEBitAIC J.U M (l) AM O(l) ~2.3 ;15 45 1~3 18 39 ~23 :22 ~2 ] 1 23 ALGEBitAIC SUM Ull AltO (121 166 :47 TIME Z~E CORR ECTIOI't ~~6 1$6 : I ~6 11201' 12)1 ''" ~e 93 :24 ALC.EBRAIC SUMIJ) AN0(4 ) s 1 25 LOC COS(H) ~~ 1.2 ;45 In 9~ 231 1' 6964 10 I RIGHT ASCEIUIO!ol OP' ST.t.R f UlL£ 10, 10. 111 /LJ, 01t Ill 20 14o I ~~ 20 :40 )6 20:40 ~6 110 I,, I co D::J -e m 7 :436 :45 7:439 :90 7 it41 : 70 I" (f01i." OW flfVEIUE IF USING MILS SOUTH II, DECUHATIOH OF STAit OH Cll!fHWICH DATE .0 I IIIE.t.H HOIIIZOHTAL AHGLI! " 3:146:64 3-~46:25 3 ).49_}7 ... CTA&t. £ 10, 10-.MIU, Olf: Ill 11 • -'1 1 cnt-t•o•= dTilOH~tc AZIMUTH TO M.ARIC 19 1 At.CEIRAtc suM t1n ...... o 1111 4 :291 :61 4_l91 ;65 1 4 ~91 :n 1" 20 I \ll Of" 11'1 ,." * 1,-UIIS 4HO C. IH (6)1S I + 1 AHO llSS THAN 2~ t1ti"i I + I AH D ....OilE THAH" HilS LOCAL DATE•I DA Y ~ {5)-14 HIU ,_, lCH ECitEil LOCAL O.t.TE-1 OAT 2~ HRS-UI JSI'4EET DA ,~~:~.6-10a REPLACES EDITION OF 1 SEP 53, WHICH IS OBSOLETE F igu1·e 133-Continued. .., ..... determining this value depends on the celestial body observed, hence the differences in DA Form 6-10 and DA Form 6-10a. The procedure on both forms starts with the value of GMT and evolves to the local hour angle (LHA). (a) To determine the hour angle of the sun on DA Form 6-10, proceed as follows: 1. On line 7, enter the equation of time at 0h which is extracted from the Army Ephemeris by using the Greenwich date (line 6). 2 . On line 8, algebraically add lines 6 and 7. 3. On line 9, enter the correction to the equation of time at GMT. The correction is read from table 2, using the daily change from table 2 and the GMT. 4. On line 10, algebraically add lines 8 and 9. This value is the Greenwich apparent time (GAT). 5. On line 11, change GAT to Greenwich hour angle (GHA) by adding or subtracting 12 hours. The final total must be less than 12 hours after the longitude correction is applied. 6. On line 12, convert GHA to mils of arc. Perform the conversion computation on the back of the form. 7. On line 13, convert longitude which is expressed in degrees, to mils. Perform the conversion computation on the back of the form. 8. On line 14, algebraically add lines 12 and 13. This value is the local hour angle of the sun. It must be less than 3,200 mils. (b) To determine the hour angle of a star on DA Form 6-10a, proceed as follows: 1. On line 7, enter the sidereal time value for 0h which is extracted from table 2 of the Army Ephemeris by using the Greenwich date (line 6). 2. On line 8, enter the correction to the sidereal time for a partial day. The correction is extracted from table 4 of the Army Ephemeris using GMT as an argument. 3. On line 9, add lines 6, 7, and 8. This value is Greenwich sidereal time. 4. On line 10, enter the right ascension which is extracted from table 10 or 11 of the Army Ephemeris, using the star number and Greenwich date. 5. On line 11, subtract line 10 from line 9. This value is the Greenwich hour angle. 6. On line 12, convert GHA to mils of arc. Perform the computation on the back of the form. 7. On line 13, convert longitude to mils. Perform the computation on the back of the form. 8. On line 14, algebraically add lines 12 and 13. This value is the local hour angle of the star. It must be less than 3,200 mils. (5) On line 17, enter the value of the latitude of the station in mils. To convert the latitude from degrees to mils, perform an auxiliary computation on the back of the form. (6) On line 18, enter the value of the declination of the star or sun. Declination of a star is extracted from table 10 or 11 in the Army Ephemeris. Apparent declination of the sun is computed on the back of DA Form 6-10 by using table 2 in the Army Ephemeris. (7) Use lines 19 and 20 to determine the value of 1ft (Lat+Dec) by adding lines 17 and 18 and dividing the sum by 2. (8) Us e lines 21 through 24 to determine the value of 1ft (Lat-Dec) by subtracting line 22 from line 21 and dividing the result by 2. (9) Use lines 25 through 30 to solve, with the use of logarithms, the value of the angle 1ft (A+q). (10) Use lines 31 through 36 to solve, with the use of logarithms, the value of the angle lj 2 (A-q). AGO 10005A STll.._ SI./NPirMI OltD!I\ ASTI.OMOKIC AZIMUTH COMPUTAtiON .tJIIl 11\JMUI I~PPROX. AZ ~2-f-JM tsl~!~ WT TO AZ MX 4-L-91 STATION SD 260 TE MP 1/0 OF WATCH TIM! HORIZOKTAL F..LD DATA I Of OIISU.V IANGLE VER~!CA.L 1 1 SET HO . I 09 2~ // .375'1 1~ + Jl':"S""q l s 1 S!TNO. z o'1 2.'1 1 1~ 37t.B 1 o '' l-~o97o 1 S? SET NO 3 or 1 32!4 . .37771h + ~1}'113 SET NO . I I I I S!THO. I I I I I I sn NO . I I SUH 2i1ZS 1to 11 3os1.z 2&t31b I MEAN o'/12"!12-' .3 7(.gl +.. WATCH 871 12 .3'i~81)4 UPR.ACTION 2 CORR :~~ ~24 I 4 12/ !.(6) • IKILS IK TENS OF ~ !5'.31 12. 23 SECONDS lzo 39 ()7) + ()8) 933100 KlLS IN UNITS OF 8 *"* • GKA ~ .3 1 .3/ 12.7 24 SECOND6 l o-4 40 ~~~T~t!.:; ~t:, 135" 9 I ~~·~~T~~T'!':. 2\ + I I 25 r.;; ~~9~1~RU(24l ~1&. 1.Z-4 41 LOG ()9) Z I 'I6'?6'9.Z IO ~~~~ION TO ( 9 ) + I I LOHCITUD! $ 18 124 ' :li 42 LOG ll •• * + I I 26 (40) 9 1544nM1 -~~~=•~DS ! 43 LOG CONSTAMT 6 I 841638 ( 4)+(9)+(10)+(11 + I HILS IN TENS OF 12 • cH..oo 1.ST -I 27 DECRIES 1 to oofoo 44 (41)+ (42 )+ ( 43) 9f3.-f:?SKH MILS IN UMITS OF ~~~.~F.ii~f~~~\,~ f? oo1nn 28 DECREES I 4-2 17? 45 ~~N(44J, b 1p::j I ~~OF GilA IK KILS IN TEllS OF 14 SEC OP GRA IN I~ / 371 7? 29 KIKUTtS 5 193 46 ~ DA~ ~~,;'u0~~-~ 41 t. 144 ~u.> •• UftlT> ur In tilLS ~ z 1oo 30 KIKUTtS I I I q 47 <:5~~~t~~ :c~ 4/t,l Zl l6 ~NGIT~~.. ~ST •. iJ.... I 74<). +.3 " ~~~ T!KS OF STAR (TABLE 10) 13)+(14)+(15)+ KILS I N UNITS OF 16 -1;., 3 o'11t.s-32 !o4 LilA SECONDS I ....... , 1;.., 1109165 H I~ !!.~~2~UH I 74"'1143 • •tF + · ~~ ~' +)lolLS> 1lWO 24h ~·~· ~.;~::,.•::;;1~~~~~ u~.·~~- Aat.rLA.R KP:ntOD USE I.O!ICtT'D'ta +)6HORE THAN 24h (-) LOCAL DAT! +I (-) (+) LOCAL DATE -1 ::;,. r:::::\ ~F 1:.,.;:/SICK(-)IF 1.011:1- IF 7 IS : --..l.!l......! ..._. (IF 17 ts, P8l IS: ( -)OR(+ ) AND USS THAN 12b (7) + 12b ( -)OR 0 TO 3200111 REF !AT ( 17) .. ! o5 0:?: + AHD HOR! THAN l2h (7) -12b 3200111 TO 6400ol 6400111-(17) SlGN (-) IC)l! T!WI ~ (17)-6400oi SIGN (+) HOUR ANGLE HEntOD ALTinJD! K!THOD ALTIT\IDE·HOUR ANCU KETHOD ~· 1 2 (18\ ~ 4-04132 64 1600-00 tilLS + 80 LOG SIN Ill) I 49 1/2 (25)~~ ~ le::' ..30jll /2 65 ~~~~~ICM I I -II LOG _COS (47) 50 1/2 (47) ~ 2oBI 1 0 66 ( 64) + (65) • p I 82 COLOG COS ( 36) T • 51 (49 + 50\ ~ ..::)/ t-1 .zz 67 REPEAT )6 ! 1 3 ( 80)+ ( 81)+ ( 12) I I ~trrlt.OC SlN 52 (49 -(50 \ I~ l oo 1oz 68 K!PEAT(25);:;:;.;.~- ( OJ)• T 84 53 COLCC SIN 5I o 1 .31 .~9. ~...; I ! !n'!R IN 69 ( 66)+ ( 6 7)+(68) 85 -A ,.,. T I w.. LCC COS 152\ 9 1 997'10~170 112 60\ •• . POLU.IS TABUUR HEntOD 5 LOG COT 48\ o i 3J7ot4 11 70\ -66 I VALUES I 86 0 OITAIN!D 56 53) + (54) + (55) ol ~'.1.?52. n COLOG COS ( 6 7) I 87 l ;.a.. UBI.£ 12 I • 57 COLOG COS (5 1) olo5?333 73 COLOG COS (681 I T 88 2 IlliG LST ! 12\ 58 LOG SIN (52 ) .?1 '1'11302. 74 LOG COS !701 I •• lro•~ ,.?l±iJI81 I 59 REPEAT (55) o I o77ot+ 1 LOG COS C71 I 90 ~Jr. ,.., I 160 '1 1 4-zt-~49 76 72)+(73)+(74)+(75 I 91 LCC FACTOR ,T 471 1 6 1 lu~1~/A~1:60) 0 2&.}~ r 77 1/2 (76) 92 COLOG COS (25) T ~~~RT'(';2~>0) ~/.3941 3 62 78 AHTILOG COS ( 71~ ! 93 ( 90)+1911 + ( 92) I 63 I~<~>,;,~ + ltPtPo11 79 1!~~7~! ;.~ I 91 I ~:;";.(~~~'• A I ~ ***** (84) IS lllARIMC ANGLE US! APP ROXC<117 TJTER AZIK11nl TO AZI H11Ill HARK AZ TO D!TERHINl VALUE OP A 95 A- Rnrho1 1 ~•IIORIZOtrrAL CHECKER Z TO ITAR • A WHEN STAR IS IN EAST 96 376>~14 73~ ~I • 6400 -A llH!K STAB IS IN ll!ST AZ TO - D tr (j5) 19 LIN T!WI ( 96) 97 <95)-<96)·Az "" 42'111 7 OA FORM 2973, 1 Moy 65 Figure 134. DA Form 2973 showing computations by t he hour-angle method, using the sun. 219 STAI JAa /2E~€_ffi. PlrrH OR.O!lt ASTI.OMOMIC .UDWI'H COKPlTI'A'I'ION AliD IIUI!BU t-.9 ~I AZIMUTH I~PPROX. AZ STATION so 2~0 TEKP 83 ., ~L Z-1-Jv-v '51 ....... w TO AZ KK 42 I VERTICAL WATCH TIM! HORIZONTAL nnnru.u OF O'L!I!.I.V 1 111 104 3/501 0 + 8'4~14- SET NO I I I I S!T NO . I I I I SET NO , I I I I S!T NO . 69 !'43 1o2 9-4-451 0 Z5ofDI 1 SUM 2.3 114 131 31483 33514 I MEAN llPRACTlON WATCH I CORR ~~ <:' 24 1 04 128 'r .3+ '!>Cf 14$ ' ITHIJ' 2 LATTITVDE HlLS IN T + I I Hll.S IN TENS OF I 5 CV DATE TAOU: 21 • 21 IHlHltTES s I s>r 3 7 CHT (41 x 60 + Hlt.S IN UNITS OF NO. OF KIN IN I 6 ~~A~~ThAT CHT -I I 22 IHliiiTrES .z 1 ~7 38 CIII 141 (4)+(5)+(6) • + I I=~~~; rm or I Zo 39 (37) + (38) I 7 OAT +-' I 23 DAILY OIAI«;E 1M 1>0 I KlLS IN UNITS OF 8 ** • CHA I 24 SECOND6 I 01-40 CLIIIATIOI tAIIZ 2 • UT lN HILS LOC (39) I 9 I ~!D~~T~~T~ 2 10 19 1 11 14 1 25 SUM (19) THRU(24 61'-1Z+ 41 ~~~CTIOM TO (9) 152 LO!ClTUilE <]) '15' '2+·1 , ; I 42 LOC (40) 10 "" + MILS Ill KUli'DR!US I 6 I ... I ;,20 140 1/6 26 OF MCRE.l.S 43 LOG COliSTAlf'l' 841638 ..ll Hits IN T!liS OF I (4)+(9)+( 10)+( II ~ Z I 5""/ 1/"-27 D!Cl\E!S l~ooloo 44 (41)+(42)+(43) 12 • r.•• OB. .LSI 13 mi~F..'i~1~~~\, (f) 533133 28 ~~~R£~~ VNITS OF I 1-Z I Zz 45 ~~E~~M~~~ -I I 14 I :g:c.OP CHA IH <:' zz~l r,J 29 ~::rr~= ,.,., ur 5 1 93 46 ~ ,:'~ '(~A:L!u;) • SEC OF CRA Ill ~~; u•m ur (;5~~·~~-~~ :c I? so:zl7; ~ /I /'1 30 11/9 47 HlLS KlLS IM T!MS OP STAR (TAIIZ 10) 16 ~"'.:!~~~'~!/_ ;, 174q14-3 OCOHDS 1os ll)+(l4)+( 15)+ HlLS IN VNITS or l7 6\ • LHA ~ '178124 32 SECONDS l oi' '~ IR KlLS SUH • 1;, 993121-' ,.,.., 2 174-9 14-3 l8 -. i!r....., ,;,.,. 2.~ R&r i!Qo iAcxrD&' ~-~~":;'j;I~,..~V!,.RS~~ u~l"~;'l.~- ABULA.R M!T110D US! LO~IT"D"DE +)6HORJ< THAll 24h (·) LOCAL OAT! +1 (·) ~~':::~· ;.1:..;:/SICM(-)11 LOICI· (+) LOCAL DATl ·1 17 IS : (18! IS: -IP (71 IS: --.ilL!L -IF t~* (-)OR(+) Alii> IZSS THAll 12b (7) + 12h ( ·)OR 0 TO 320011 Rl 7o?14i' 6 7 RlP!AT 361 I 83 ( 80)+(81)+(82) I I ~lI" (OJ)• I 52 _{49)_-_150} Q 5'.3 1.24 68 Rl R33 4.9.2 R'q -00"1 oof -"· 01 . oo<. -.7'0PT RANSPfiRT£0 '5 MIL.€. OVE.R SMOOTI ROllO PAll I£ f.IOII<.£ i ~3110, 71.1 3380. 761 1(, ::=: -c..o 3386. 711 .1386.783 -OIZ. -02 -c.to: . 007 zoJAH" ,no UE=RR MAc I55'72 . 2U 'iS"72 22 -c..o Co~t> 55'78 .2U 'i5'78.8l.~ -008 -02"1 -. oo7 .t'07" Z2 1J.:~~ X-R.\Y J(f' TCU 1 2~72 (.Ol-D . 85, 2372.8-f.'f -t. .ot Z~78.8N 2378. 8S'i -. 006 -. oJ5 -.Oo7 .."'S' I ,.,.,s.4>r& -. oo,J -oS6 -007 ~"o': Figure 140. Sample fi eld notes for an azimuth gyro. AGO 10005A 233 correction is obtained by subtractingnomic observations should adequately deterA record should the gyro azimuth in column 8 from mine the instrument error. be kept of all gyro azimuths which provide the astronomic azimuth in column 7. a comparison to astronomic azimuths. This (10) The total of the entries in column 9 is record is used to determine the instrument entered in the total column (column correction. The record is kept on BA Form (10) . The entry on each line of col5-72. A separate record is kept for each aziumn 10 is the sum of the gyro cormuth gyro. The cover and the first page of the rection on that line and the total on record should completely identify the instruthe preceding line. ment. Figure 140 shows a sample record. The (11) The mean correction is entered in the entries made in the 12 columns of the open mean con· column (column 11). The double page of DA Form 5-72, as shown in mean correction is obtained by dividthe sample, are explained in (1) through (12) ing the number in column 10 by the below. number of entries included in the (1) The date and hour of the observations total. are entered in the date-time column (12) The weather, the initials of the gyro (column 1) . operator, and any other data which (2) The name of the station over which might affect the accuracy of the rethe instrument is set up is entered sult are entered in the remarks colin the sta column (column 2). umn (column 12). (3) The name of the station used as an e. If for any reason, such as cloud cover, an azimuth mark is entered in the az mk astronomic azimuth cannot be observed and a column (column 3). reliable grid azimuth is available for the ob (4) The azimuth of the observed line if served line, the gyro azimuth can be compared known to a higher degree of accuracy with the grid azimuth. This is done by applythan can be determined by artillery ing the convergence, with sign reversed to the astronomic observations is entered in grid azimuth to obtain a true azimuth. The the known grid azimuth column (colresult is entered in the astro azimuth column umn 4). and the value is inclosed in brackets to indi (5) The grid azimuth as determined by cate that it is computed. The other values for the azimuth gyro is entered in the entry on DA Form 5-72 are obtained in the computed grid azimuth column (colsame manner as when an astromonic azimuth umn 5) . The gyro correction from is used for comparison. All events which might column 11 and the convergen ce from affect the accuracy or gyro correction of the column 6 are applied to the observed instrument should be written boldly across the gyro azimuth to obtain the computed double page. If it is certain that the accuracy grid azimuth. A comparison may be is affected, a new series of totals should be made here as a check during training. started. If it is probable that the gyro correction is not affected, the series may be con (6) The grid convergence is entered in tinued by the survey officer should watch the the C column (column 6). The concorrections carefully to determine if a changevergence must be computed or scaled in the correction occurs. Examples of eventsfrom a map. which should be entered as follows: (7) The astronomic azimuth computed ( 1) Transported 25 miles over smoothfrom the observations is entered in road. the astro azimuth column (column 7}. (2) Transported 10 miles over rough road. (8) The azimuth determined from one set (3) Transported 2 miles across country. of gyro observations is entered in the gyro azimuth column (column 8) . (4) Trim pots adjusted. (5) Severe cold (minus 50 ° F in ware (9) The gyro correction is entered in the gyro corr column (column 9). The house) 2 days. AGO 10005A 234 (6) Severe heat (140 ° F in warehouse) g. Close the control indicator cover and se12 hours. cure the cover with the five latches. (7) Serviced by maintenance section. h. If the sensing element is to be trans(8) Hit severe bump during transportaported, remove the theodolite from the brackettion. and carry the theodolite in the issued theodolite base and carrying case. 321. Taking Down the Instrument i. Connect the carrying c2se heater wire to a. After measurement is made with the azimuth gyro approximately 10 minutes is rethe sensing element connectnr. quired from the time the gyro rotor is shut off j . Unscrew the tripod fixing screw and, usinguntil it comes to rest. To diminish this coastthe two handles provided, remove the sensinging time when the SELECTOR switch is in element from the tripod and carefully place itFWD, turn the SELECTOR switch to REV in t he carrying case. for 45 seconds and then to OFF; when theSELECTOR switch is in REV, turn the SEk. Connect the heater wire from the sensingLECTOR to FWD for 45 seconds and then to element to the bracket receptacle.OFF. This method of power reversal brings l. Position the collar and cushioning. the rotor nearly to a standstill. Monitor the rotation -of the rotor by placing an ear against m. Check to see that tools are secure. the sensing element. n. Install the carrying case cover and secureCaution: To avoid possible damage or misit with the six hook-type clamps. alinement, never remove the sensing elementfrom the tripod or transport the sensing eleo. Close the pressure relief valve and securement while the gyro rotor is running. the dust cap on the electrical connector. b. Turn the SELECTOR and CIRCUIT p . Clean, fold, ar!d secure the tripod legs. TEST switches to OFF and secure the azimuth lock with light pressure. 322. Care and Me intenance c. Disconnect the power source. Adjustment and repair of the azimuth gyro d. Disconnect cable number 4 from the sensmust be performed by qualified instrument reing element. pair personnel. Artillery units, therefore,should turn the in ;trument in for any neces e. Disconnect cables number 4, 6, and 1 (or sary adjustments oc repair to the engineer unit5) from the control indicator. responsible for pro"iding maintenance service. f. Store the cables in the canvas bag with TM 5-6675-207-lfi outlines the categories ofthe loose equipment. maintenance for the instrument. AGO 10005A 235 PART FOUR CONVERTING OATA CHAPTER 15 CONVERSION TO COMMON CONTROL 323. General 324. Variations in Starting Control a. In order to permit the delivery of accurate The methods by which starting control for field artillery fires without adjustment and to field artillery survey can be obtained are listed permit the massing of fires of two or more in order of preference in a through c below. artillery units, all field artillery units oper a. Use of Known Co01·dinates and Heights of ating under the tactical control of one com Points Located With Respect to a UTM (o1· mander should be located and oriented with UPS) Grid. The points for which the coordirespect to a single datum plane or grid. This nates and heights are known may be pointsgrid can be based on the UTM (UPS) grid established by surveys performed by the highercoordinates of points previously established by survey, or the grid may be based on assumed echelon, or they may be points which were located by surveys performed prior to the start data. of military operations. The locations of points b. The common grid is established by the established prior to the commencement of mili highest survey echelon present in the area. The tary operations are contained in trig lists pre headquarters which exercise tactical control pared and published by the Corps of Engineers. over artillery units are battalion, division, and corps. The mission of the subordinate unit reb. Us e of Assumed Coo1·dinates and Heights quires it to initiate survey operations without and Correct Gr-id Azimuth. Correct grid azi waiting for survey control to be established by muth can be determined, in many cases,a higher echelon. Therefore, at all levels, sur through astronomic observation or through thevey is started and completed as soon as possiuse of an azimuth gyro. Correct grid azimuthble, and, when higher echelon survey control should always be used whenever possible. Ifbecomes available, the original data is conboth higher and lower survey echelons initiateverted to place the unit on the grid of the surveys by using correct grid azimuths, any higher echelon. Thus, it may be necessary for discrepancy which exists between surveys due a battalion assigned or attached to a division artillery to operate first on the grid established to assumption of coordinates will be constant by the battalion (battalion grid), then on the for all points located (fig. 141). When it is necessary to assume the coordinates and height grid established by division artillery (division grid), and finally on the grid established by of the starting point, they should approximate corps artillery (corps grid). When survey at the correct coordinates and height as closely as possible. The approximate coordinates can one or more echelons is based on assumed data, be determined from a large-scale map. The use data established by the lower echelon must be converted to the grid established by the higher of starting data determined from a map must always be considered assumed data. echelon. AGO 10005A 236 azimuth but one (or both) echelon (s) starts ERROR IN ASSUMED AZIMUTH (start) with assumed coordinates and height,the lower echelon must apply coordinate andheight corrections to the location of each cd TS 2 tical point to convert to the grid of the higher TSI TS3 echelon. This coordinate and height conversion PLOT OF TRAVERSE PERFORMED USING AZIMUTH AND COORDINATES is commonly referred to as sliding the grid WHICH ARE CORRECT WITH RESPECT TO GRID. PLOT OF TRAVERSE PERFORMED USING CORRECT AZIMUTH AND (fig. 142) and is accomplished as follows: INCORRECT COORDINATES WITH RESPECT TO GRID PLOT OF TRAVERSE PERFORMED USING INCORRECT AZIMUTH a. Determine the difference in easting and ANDCOORDINATES WITH RESPECT TO GRID. northing coordinates and the difference in Figure 141. Discrepancies in survey control caused by height between the assumed coordinates anduse of assumed starting data. height of the starting point and the commongrid coordinates and height of the starting c. Use of Known or Assumed Coordinates point. and Assumed Azimuth. Assumed azimuth Easting Northing Height should be used for a starting azimuth only Assumedwhen azimuth cannot be determined by astrostarting point: 550000.00 3838000.00 400.0nomic observations, an azimuth gyro or comCommon gridputation. The assumed azimuth should approxistarting point: 550196.52 3837887.89 402.3mate the correct grid azimuth as closely as Correction : +196.52 -112.11 + 2.3possible. The approximate grid azimuth can The difference becomes the correction when thebe determined by scaling from a large-scale difference is given a sign which will cause themap or by using a declinated aiming circle. If algebraic s um of the assumed data and the coreither (or both) higher or lower echelon surrection to equal the common grid data.vey operations are initiated with assumed azimuths, differences of varying magnitude will b. Apply the corrections algebraically to theexist between the coordinates of points located coordinates and height (as determined by theby their surveys (fig. 141) . This variation comlower echelon) of each station to be converted.plicates the problem of conversion to commoncontrol. For this reason, assumed azimuth 326. Azimuth Conversion (Swinging should never be used if the correct grid azithe Grid) muth is known or can be determined. If a unit initiates survey operations usingcorrect grid coordinates but assume azimuth 325. Coordinates and Height Conversion (Sliding the Grid) for the starting point, the coordinates of each station in the survey and the azimuths deter When both a higher and a lower survey echemined by survey will be in error when correct lon start survey operations with correct grid direction is determined for the starting point. Assumed coordinates of BnSCP Btry SCP onassumed grid IIldN LdE__ TS2 Azimuth Btry SCPtomk on common grid Figure 142. Sliding the grid. AGO 10005A 237 t_______________________ mined for each station in the survey, thus plac In order to convert the assumed data to correct grid data, all azimuths and coordinates ing all stations on the common grid. determined in the scheme must be corrected. d. If it is desired to determine the common The application of the azimuth correction is grid data for a specific point only, compute the commonly referred to as swinging the grid. azimuth and distance from the starting point The procedures for swinging the grid are as to the designated point (assumed data) . Apply follows: the azimuth correction to the azimuth determined and recompute the location of the des a. Determine the difference between the as ignated point from the starting point, usingsumed starting azimuth and the azimuth ob tained from common control. the corrected azimuth and the distance determined by computation (fig. 143). Assumed starting azimuth: 2,800.0 mils Common grid starting azimuth: 2,922.7 mils e. To correct the azimuth of an orienting Azimuth correction: + 122.7 mils line, apply the azimuth correction to the 3;ZiThe difference becomes the azimuth correction muth determined through the use of assumed when the difference is given a sign which will data. cause the algebraic sum of the correction and the assumed azimuth to equal the common grid 327. Azimuth, Coordinates, and He ight azimuth. Conversion (Swing and Sliding b. Apply the azimuth correction to each leg the Grid) of the survey. If either (of both) a higher or a lower survey echelon initiates survey operation with c. Since this will change the azimuth of each, the bearing angle of each leg will be changed. assumed azimuth, coordinates, and height, t h e lower echelon must apply azimuth, coordinate, Recompute each leg of the survey by using the and height corrections to critical locations andcorrected azimuths and new coordinates deter ~ \ Common grid azi muth to az mk \ Assumed \ azimuth to azmk \ \ 33.29 rfl azimuth error \ \ \ 33.29ril 900meters) ~~~----~a~zi=m~u~th~~~~~~~~~~----------------~• Btry SCP oncorrection grid started with Assumed azimuth 5874. 4611\ --f9oo assumed azimuth Common grid azimuth 5907. 75 11\ -.....: ...!!l!ters) -.....:-._ Azimuth correction +33. 29 ftl Computed azimuth BnSCP to Btry SCP t534.t2m Azimuth correction +33.29rtl ---& Common azimuth BnSCP to Btry SCP 1567.4111\ BtrySCPoncommon grid Figure 149. Swinging the grid for a specific station. AGO 11>005A 238 directions to convert to the grid of the higher point to the first critical point and from the echelon. This technique is commonly referred first critical point to the second critical point. to as swinging and sliding the grid and both Continue this sequence of computations until swinging and sliding may be accomplished at the closing point is reached. the same time. Only the critical points (e.g., battery centers, Registration Points, OP's) are b. Determine the azimuth correction by comconverted. The steps in swinging and sliding pa ring the assumed starting direction with the the grid (fig. 144) are as follows: common grid starting direction. Apply the azi a. Using the assumed coordinates, compute muth correction to each of the computed azithe azimuth and distance from the starting muths determined in a above. /'---...... / ........... Original survey on assumed grid with / '---n azimuth corrected by swinging ' / / -~ ~~I ~ ----"" f ...... -.--I"'' Assumed I Y / "'-. \azimuth / I ) '-'~ ~ \/ ;II / / Correct~~\ // // I azimuth ~1_ 11 / I /~ / I Azimuth lk:--------IS' _-t{ difference -...._~ --Assumed ?...._...._ ...._ Azimuth difference applied as a __ ~-BnSCP ~-correction to each leg causes the Original survey on assumed grid to swing grid and azimuth Original survey corrected by swinging and sliding the grid'\ dN L'~ dE I I I ldN I LstE_J / /\Original survey on assumed Common // grid with azimuth corrected grid BnSCP by swinging A"•med BoSCP I Difference between common grid on/assumed grid applied at starting station causes grid to slide Figure 144. Swinging and sliding the grid. AGO 10005A existing critical points, including the battalionc. Using the common grid coordinates of the (b survey control point and a line of direction tostarting point, the corrected azimuths the azimuth mark, and then the critical points above), and the computed distances between are transferred to a new chart. The procedures critical points (a above), compute the coordi nates of the first critical point. Using the new are as follows: coordinates of the first critical point, the cora. Plot the coordinate locations, as deter rected azimuth, and the computed distance to mined from assumed data, for the battalionthe second point, recompute the coordinates of SCP and all critical points. Plot the azimuth the second critical point and continue the com(assumed) to the mark on the chart. , putations until the closing point is reached. b. Place a sheet of overlay paper over the d. Correct the height of the critical points by chart and prick the locations of the battalion applying the height correction. SCP and critical points. c. Trace the line of direction from the chart 328. Swinging and Sliding the Grid to the overlay. (Graphically) d. Plot the common control coordinates of theThe procedures discussed in paragraph 327 require considerable mathematical computabattalion SCP and the common control azimuth tions in order to convert to common control. to the mark on a new chart. If t ime is critical, a graphical solution to cone. Place the overlay on the new chart, alin version to common control can be used. Howing battalion SCP on battalion SCP and azi ever, control cannot be extended from data obmuth line on azimuth line. tained from a graphical solution. Normally, the graphical solution is used in conjunction f. Prick the locations of all critical points with a firing chart. An overlay is made of the shown on the overlay onto the new chart. AGO 10005A 240 CHAPTER 16 CONVERSION AND TRANSFORMATION Section I . CONVERSION OF COORDINATES 329. General Occasionally it may be necessary to convert grid data to geographic and/ or geographic data to grid data. a. When coordinates are transformed from a UTM zone to a UPS zone or from a UPS zone to a UTM zone, it is necessary to convert grid coordinates to geographic coordinates and then to convert the geographic coordinates to grid coordinates for the new zone. (To transform a grid azimuth from a UTM zone to a UPS zone or from a UPS zone to a UTM zone, it is necessary to convert the true azimuth to a grid azimuth for the new zone; this is accomplished by subtracting the convergence from the grid azimuth for the old zone and applying the convergence for the new zone.) b. When only the geographic coordinates are known for a point which will be used to initiate or check survey operations, it is necessary to convert the geographic coordinates to UTM (or UPS) grid coordinates. (Geographic coordinates must be correct to the nearest 0.001 second to obtain UTM (UPS) coordinates correct to 0.03 meter.) c. When azimuth is obtained from astronomic obesrvations, it is necessary to know the latitude and longitude of the astronomic observation station. If they are not known, the geographic coordinates of the station can be obtained by conversion from grid coordinates. 330. Conversion of Distance Before the distance between two points can be determined, the coordinates of both points must be based on a common system (for example, both geographic coordinates or UTM coordinates) . If the distance is computed from UTM coordinates, the log scale factor must be applied to obtain ground distance. 33 1. Procedures for Conversion of Coordinates a. The procedures for converting UPS grid coordinates to geographic coordinates and for converting geographic coordinates to UPS grid coordinates are discussed in TM 5-241-1. b. In artillery surveys, UTM grid coordinates are converted to geographic coordinates and geographic coordinates are converted to UTM grid coordinates by using DA Forms 6-22, 623, and 6-25 together with the technical manuals containing data relative to the appropriate spheroid. TM 5-241-1 contains a map showing the various spheroids. A spheroid is an assumed size and shape of the earth for the purpose of computing geodetic positions. c. The spheroids and their associated technical manuals are shown below : l n ternation nt Sphe1·oid (South America, Europe, Australia, China, Hawaii, and South Pacific): TM 5-241-3/ 1 and TM 5-241-3/ 2. Cla-rke 18 66 Spheroid (United States, Mexico, Alaska, Canada, and Greenland) : TM 5-241-4/ 1 and TM 5-241-4/ 2. Bessel S pheroid (Japan, USSR, Korea, Borneo, Celebes, and Sumatra) : TM 5241-5/ 1 and TM 241-5/ 2. Cl(w k e 1880 Sphe1·oid (Africa): TM 5241-6/ 1 and TM 5-241-6/ 2. Everest Spheroid (India, Tibet, Burma, Malay, and Thailand): TM 5-241-7. AGO 10005A 332. Use of DA Form 6-22 (ComputationConversion UTM Grid Coordinates to Geographic Coordinates (Machine)) DA Form 6-22 (fig. 145) is used to convert UTM grid coordinates to geographic coordinates. Instructions for the use of the form are contained on the reverse side of the form. Figure 145 shows an example of the entries that are made on DA Form 6-22 for converting UTM grid coordinates to geographic coordinates. The longitude of the central meridian (item 39) can be obtained from the UTM grid zone by using the table on the reverse side of DA Form 6-22. The UTM grid zone number can be determined from a map or from a trig list. 333. Use of DA Form 6-23 (ComputationConversion Geographic Coordinates to UTM Grid Coordinates (Logarithms)) a. DA Form 6-23 (fig. 146) is used to convert geographic coordinates to UTM grid coordinates. Instructions for the use of the form are contained on the reverse side of the form. Figure 146 shows an example of the entries that are made on DA Form 6-23 for converting geographic coordinates to UTM grid coordinates. Longitude of the central meridian (and UTM grid zone number) (item 2) is obtained from the table on the reverse side of DA Form 6-23. b. Logarithms entered on DA Form 6-23 must be correct to the seventh digit in the mantissa. The complete number for which the logarithm is obtained must be used as the argument in obtaining the logarithm. The mantissa of the logarithm must be determined to the eighth digit and then rounded off to the seventh digit. Antilogarithms must be determined to the third digit after the decimal point. 334. Use of DA Form 6-25 (ComputationConversion Geographic Coordinates to UTM Grid Coordinates (Machine)) DA Form 6-25 (fig. 147) can also be used to convert geographic coordinates to UTM grid coordinates. (DA Form 6-25 is a machine computation form, whereas DA Form 6-23 is a logarithm computation form.) Instructions for the use of the form are contained on the reverse side of the form. Figure 147 shows an example of the entries that are made on DA Form 6-25 for converting geographic coordinates to UTM grid coordinates. Longitude of the central meridian (and UTM grid zone number) (item 2) -is obtained from the table on the reverse side of DA Form 6-25. AGO 10005A COMPUTATIO N -CON VER SI ON UTM GR ID COORDINATE S TO GE OGRAPHIC COOROI~ATES (MA CHINE ) STATION UTM GRIO HEMISPHERE: 0CJ NORTH c::J SOUTHFlat Top ff 2 COORDINAT[S:E 559 .858 . ~Q ,N 3 I R36 I 632 I 3lQ UTM GRID ZONE NIMIER 14 I EASTI NG CO~OINATE OF STATION I TABUlAR VALUE FUNCTION IX OPPOSITE I( Ae aecur•tel y •• t nrwn) 559 :858 1430 25' U.TITUOC IN (JO) 39 291! 762 6 0 o I o o o I o 0 0 26 ' TABUlAR DIFFERENCE FOR I SECOND OPPOSITE I I z ::m:: ::m:m : mm:::::: ::::: ,~ :: :::::::~ TABULAR VALL( Of' FUNCTI~ IX IN( 2$) 11111::::.- I l 0 l 131 I 19 I I TARULAR VALUE FUNCTION X OPPOSITE I27 ' IF ( 1 ) IS MORE THAN ( 7), USE ( 1) -(2) !::\ U.TITUOC IN ( J'O) 3 IF (1) IS LESS THAN (7), USE (7)-(1 I L I IIIi~ I 3151 2_5_4 (Si•n.• l•• Y• +) (t) I I 2B ' T48UU.R DIFFERENCE FOR I SECOND OPPOSITE I I TABUlAR VAWE OF FUNCT! ON X IN (71) : 59 1858 !430 [llil\i ii 0 • 004 I 23 " REPEAT (J) WITH OCC !MAL POINT I I fiRAPHIC VALUE 6 2(1X) MO;ED LEFT SIX PlACES 29' ~~[ (11) AS ARGUMENT . ENTER GRAPH AT ~~~,"~~~~~~ 059 1858 143 0 EFT S IDE (Si.n •l••Y• -Jj (-11HHHH' ""'''"'"''' 001 I I '"""""'": 5 ( 4 ) X ( 4 ) GRAPHIC VALUE E5 = SECONOS OF ARC HHH I:~:, 003 1583 1032 LUS E STEP (4) AS ARGUMENT AT LEFT SlOE .:·ii,: I I 30' OF GRAPH. US E STEP ( JO) AS ARGUMENT ::::: 6 ( J ) X( 4 ) AT TOP OF GRAPHj li. 000 1214 1475 :u:: "'""''""' 0 I I '""" I 6) X ( 4 ) 31 (11) X(26) 000 J 012 1838 :::::~ :: :\\ d 31 216 NORTH lNG COORDI NATE Of STAT ION I 0 0 0 o 1ooo 1 o 0 32 HGEBRAIC SUH(2$),(1P).AHD ( JJ ) I I 0 (t) (Si • n •l••Y• +) lc'A• aeeureteJy •• inown) IF I I I 391 294• 97? HOUSPHERE I S SOU TH, USE I I I B l O, OOO , OOO.COO MI NUS NORTH ING (J2) X (4) =sECONDS OF ARC 33 (t) 2 1 352·~ 136 COOR DINATE OF STAT IONj (Si -n •l..y• +) I I lli~l I I I 3• (11) X(21) I 3 1 836 1637 _1310 j::::: ::::::: 0 ~ 10lf 9' TABULAR VALUE FUNCTIOft I NEAREST I I I I TO AND LESS THAN VALUE IN II) 35 (34) +(21) 1::::::: 3 1 835 1882 Lt31 "~~: I 315_1 358 10' LATITUDE: IN DEGREES AND MINUTES (J>) X ( 6) = SECONDS Of ARC 'I OPPOSITE VALUE IN (9) i@l ol 'I } HlH 36 (-) (SJ f n a lway• -) 11.:1.:111 1 : 01 068 34 140 . "'"'"'"""" II' I A GEBRAIC SUM ( JOJ, (JJ). AND (36) = SECONDS I ' I TABULAR VALUE OF FUNCTION I IN (9) I 37 OF ARC (Si4n • l ••Y• tJ {t) TA BUlAR DIFFERENCE FOR I SECOND OPPOSITE -:::~::::'!· II30 L 801 t9.9 1. 2 1 3:5;21 068 12' TABULAR VALUE i=U..CT ION VII OPPC51TE ',· i ~:.' I I CONVERT(J7J TO DEGREES, MINUTES, SECONDS 0 1 LATI TUDE IN ( 10) 3B OF ARC 11 758 1849 :39 :12 ·: 068 0 _.,.. 13' TABULAR orrFERENCE FOR 1 S£COHD OPPOSITE m1 I I LONGITUDE OF CENTRAL ot:RIOIAN OF UTMGRID:::::::: o. 018 1 12 ZONE BEIMG USED (U.. tdh) WEST LONGITUDE TA.BUL.AR'IA LUEOFFUNCTIOHVII IH(l 2) 39 u· TABULAR VALUE FU NCTION VIII OPPOSI rE ::::::: I 99 LATITUDE IN ( 10) LONGITUDE OF STATION I 23 : 10 ill· 98°1s9'16ol 000 15' usE YHUE ' "' snr •1 AS .6RGUM(NT. IF (JP) IS WEST LONGITUDE AND ( I ) IS LESSGRAPH AT l[FT S IDE (Si f n •l••Y• -)j (-) :m.-'._,·.. 1 0 Iii l39l12 l 068 ~APH!C "LUE D6 -SECONOS cr ARC ENT(R 'HHH ::: ::~ TtuN ( 2 ), USE: (JI)f(J9) 16 (I)-( f ) ''"'"I I I IF ( JI) IS W[ ST LOHG1TUOE .t.NO (l) IS loi ORE """ •o T~H ( 1 ), US( ( 3 9)-( 38) i:!U: ' ' ~ I 755 1179 I I I 17 (16)7(JJ) '/~~~; "'''""'"'".iii:.··l: ' I I f (Jf) 1$ EAST LOHGilUOE AHO ( l ) IS LESSTHI.N (2), USE (3 9) -( JI) H HHHHH 24 1517 m1 I I (17) t ( 10) = APPROXIMATE U.T ITUOC Of ol 'I 'I STATION IN D£GREES, •INUTES , SECONDS If (39) IS EAST LONGITUDE AHO ( J ) IS MOREIB 34 140 124 1517 TH JN (2), USE (JI) t (J9) 98 °12o'i 47'l 932 ·., 19 (U ) X (11) : :mm:::·mmmm. · J o : 41~ 20 ( l9) +( J2 ) I I • Obtejn e d fr otlt UTM Grjd T•blee for •phero j d bein4 u•ed, Yoluae II . 11.1!'·1·· · 11 759 ! 293 I ' I 21 ( 20) X(> )= SECONDS Of ARC 1:! -::~:',: I 6 1304 22 COHVERT (1 J )TO MINUTES AND SECONDS 'I ' I COMPUTER Of ARC (-) I::::: ~::: ::,:• (Sif n •l••r• -) I 6 !304 Kissinger CHECKER 23 ( 7 ) X ( 14) ::. sECONDS OF' ARC Ji :::::::::::: :..'.~:~' .. :I .I :;;;;;;; '"" OiOOO \-Test 2• }m~~~~~JiFJ't~A~f6/.'N7), AND N o 'I 'I DATE I HEM ISPHERE SHOWN ABINE s 34 14o 1 181213 19 Jarruary 1961 DA 1 ;~, 6-22 Figure 145. Entries made on DA F onn 6-22 for converting UTM grid coo1·dinates(machine ). AGO 10005A 243 L________ ___ _ _____ __ ----------------- COMPUTAfiON -CONVER310N GEOGRAPHIC COORD INATES TO UTM GRID COORDINATES ( Logarithms) 1r lONGrTUDE IS [.1ST AND I l l IS LESS TH.\ N 121, IJH ~oo , oec. ooc -17"' IF lO NGITUC E IS W(ST ~N O Ill I S WORE TH~N 121, US E ,oo, COO . iiOO -17~1 If LO NGITUDE IS WEST AN D Ill I S LESS THAN 121 1 USE ,~01 0(;0 . 0 0 0 + 17,1 SFC J DOE Cpl R ROE DATE 1 Feb 61 DA 6-23 Figure 146. Entries made un DA Forrn fi -23 jo1· converting geographic coordinates to UTM g1·id coordinate.s (logarithms). AGO 10005 A 244 CG'4PUTATII>IC -CONYERS I ON GEOGRAPHIC COORD I NATES TO UTM •3 RID COORD IKATES cIIACBIN&J ' OBTAI NED fROM UH" GRID TABLES FORSPHEROID BE lNG USED , VOLU ME I COWPUTUt : SFC J DOE CHECftEit: If "[IIII SP itffl£ Of )UT ION IS 50UT" 1 vsr 1o,oco,ooo.ooo-( 70) OAT[! 1 Figure 147. Ent·ries made on DA Form 6-25 [o1· converting g eographic coordinatesto UT M grid coordinates (machine). AGO 10005A 245 L________________________________________________ __ Section II. TRANSFORMATION can be transformed from any point in one zone 335. General into terms of an adjacent zone. To understand When field artillery units are operating what takes place when transformation is peracross grid zone junctions, it will frequently formed, refer to figure 148. Figure 148 shows be necessary to transform the grid coordinates two adjacent UTM zones, 14 and 15. In terms of points and the grid azimuth of lines from of northing coordinates they are numbered the the grid for one zone to the grid of the adjasame, since the origin of the northing coordicent zone. Special tables, which are available nate is the equator. However, the easting cothrough the Army Map Service, permit transordinates from left to right are not a continformation across several zones in a single comuous series of numbers, since the origin of the putation. easting coordinate for each zone is the central meridian (CM) for that zone and is numbereq a. The method of transforming grid coordi500,000. Within each zone, the coordinates in nates from a UTM zone to a UPS zone or from crease to the east and decrease to the west from a UPS zone to a UTM zone is discussed in para the central meridian. Visualize point P in zonegraph 329. 14. The coordinates are 800,003-3,700,000. If b. In the UTM grid system are overlap areas the coordinates of point P were to be transeast and west of zone junctions. However, formed to the adjacent grid (zone 15), the action taken would be the equivalent of super transformation is not restricted to these over lap areas. Grid coordinates (and azimuths) imposing the grid of zone 15 over the grid of UTM\ zoNE,zccTION I CM 43-I I CM I I I 43 I N ZONE 14 42---~;;~~~==~::Jr-f----~~--J______L_____J______L_____J______l_ 42 --~---.-~ NZONE 15-- 41-T-r-i--.....-11--h/~U-LJ__J__LJ_41 -IV 40--~----~~~l~~~t~~~~~~~J___l_____J______i_____J______i_____J_ 40 ~~ ~ 39--r-----~~~lt~~:t~~~~[___J______L_____J______L_____J______t_ I 1 I 3S-~----~~--~=tt:~~J±:~~~~~'JL___J______L_____J______t_____J______l-38 I -~ + I 1 (P) I 37-~----J----=~t:~~~:;~~p~~:~____L_____t_____l_____J_____Jl_____t_ 3,700,000 d I . i I I l /:0: I soo,ooo s 9 o 8 1 2 3 4 soo,ooo s r 7 ZONE 15ZONE 14 Figure 148. ·Transformation requirements. AGO 10005A 246 zone 14 as indicated in figure 148. Actually, to be A, the resulting E and N coordinates aretransformation of coordinates involves only the for the adjacent zone B. In the Southern Hemmathematical continuation of the adjacent grid isphere, the transformed northing must be subto the grid being used and the subsequent cortracted from 10,000,000 to compute the correct rections for locations due to the change in grid coordinate. north reference. Although the location of pointP on the ground will not be changed, the value 337. Use of DA Form 6-36of its original coordinates will change with thetransformation. The value in terms of zone 15 a. The use of forms will simplif_y transformation computations. The form used for zone would be less than 100,000 meters in easting to-zone universal transverse Mercator grid co and greater than 3,700,000 meters in northing.In transformation there will be a major change ordinates transformation is DA Form 6-36 in the easting coordinates due to the coordinate (fig. 149). This form is designed for use withnumbering system of each zone and the change a computing machine. If a computing machine in grid north reference, but there will be only is not available, multiplication is performed ona separate paper by using logarithms or direct a small change in the northing coordinate, multiplication, and the results are entered in based only on the difference in the grid northreference. the proper spaces. The form is executed in astraight numerical sequence with the values inlines 11 through 18 (No, E o, a,, a z, b,, b2, c" 336. Use of TM 5-241-2 {Formerly and c2) extracted from TM 5-241-2 for the AMS TM NR 50) proper spheroid. a. In using TM 5-241-2 to extract the funcb. Formulas on which DA Form 6-36 is tion required for the formulas used in trans formation, determine first the spheroid to be based are shown on the back of the form. used by referring to the map of the world in 338. Transformation of UTM Grid Azimuth the back of the technical manual and using itas an index to determine which spheroid tables From Zone to Zone should be used. The formulas for solving transThe reasons for transforming grid coordiformation computations are also contained in nates (para 335) are applicable to grid azithe technical manual. mu hs, and the same reference tables (TM 5 241-2) are employed for the extractions of b. The tables in TM 5-241-2 are compiled functions. To understand what transpires in for 100,000-meter intervals of easting and the transformation of azimuth, refer again to northing. A station is considered to be in a100,000-meter square, and the coordinates of figure 148. On the UTM zone to the left (zone the nearest corner of this square are used for 14) . a line of direction has been indicated. The the determination of e and n and for the enazimuth of this line is represented by a hori zont al clockwise angle from the grid north fortering arguments. zone 14. If the azimuth of that line is trans c. Certain procedures must be followed to formed to the grid of the adjacent zone (zoneinsure proper extraction from the tables. 15), the line of direction does not change; (1) When transforming to the east (such however, due to a new grid north reference as zone 14 to zone 15), use the e value line, the azimuth of the line will increase. In on the right side of the table and the figure 148 it is apparent that if azimuth istransformed from a west zone to an east zone, upper sign if two signs are shown. the azimuth will increase; conversely, if azi(2) When transforming to the west (such muth is transformed from an east zone to aas zone 15 to zone 14), use the e value west zone, azimuth will decrease. on the left side of the table and the lower sign if two signs are shown. 339. DA Form 6-34 d. When the computations are performed on a. DA Form 6-34 is used for zone-to-zoneDA Form 6-36, if the initial zone is considered UTM grid azimuth transformation (fig. 150). AGO 10005 A 247 L_______________________________ _ ZONE TO ZON E UTM GRID COORDINATES TRAN SFORMATION 4 LOCAL! TY STATION FT SilL, oj 3333¥09 FI VE PLACES = Enter AM S Technical Manual No . . + : /00 >3,~ 27? SO for proper I I spheroid using values from Lines (3 ) and (9) " 12 .; ' c§:, 5f1581• S32.l as arguments. Wh en transforming to east, use In • 1 (e) value on righ t side of tab I e and upper _l 8•90'1 of signs; for transforming to west , use (e) ~~ • 2 <±> 1i,li os' value on left side of table and lower of I 16 c 1 signs . <:!> 0~ 031 17 c 2 a> __L0 j 2.fol 18 (10 ) X 2 - ( !Jl 111~ So~ 32 d:> I 5 958; 53-Z I 19 ( ll) X (16) X J (11 X ( 26 ) <± I 0 . 0 3CJ " 0 I J~S·z''l ALGEBRA IC SU M I I 2? I -I 11"I 841 ,. (5) X (22) a; l 1 1.>18 ( !B) AND (!9) ( 5) X (17) X J , 21 (I: ALGEBRA! C SUM CHANGE SI GN OF RESULT 10 ' 31/-2. '~ ( 32) , . (33 ) , AN D (Jo ) <±> s ;'19'1J23ALGEBRAI C SU M I 22 - I (20) AND (21) I 11; .605 )6 I ~ 0 0 0 _l ooooI 2' (15) X 2 LOG ( 31 ) d: I 131P" liZ 37 s 001 1710 n (11 ) X ( 17 ) X J q: (36) -(J7) I o· ~"' :18 1-J. 9'13 13290 2~ (5)X(t6l X J G: ,. LOG ~ 35) 1o· o~8 3 _1 717_j 871J3 ALGEBRAI C SUM 1 26 •o ( 2J). ( 20 ) , AN D ( 25 ) (3B) .. ( 39 ) C: 135~ 303 cS' _j _,... ,77"t_....."'"3..., 27 (12 ) + ANGLE WH OSE LOG TAN I S :too ,331:,· 211 u I (uo). USE SIG N OF ( 35 ) 0 ft,O J 39_t_ ~28 ( 11 ) X ( 22) ( 1) + r ~ I S·K35 • 2 751/7(:~8~ ALGEBRAI C SU M 1 2'1 REPEAT (01 ), CHANGE S IGN ~ ( 27) AN D ( 2B) + : /01J 330" 4/'f..J.. ., ~0 839 F'OR SOUT HERN HEMI SPHERE (5) X ( 26 ) CHANGE ALGEB~41 C SUM (oz ) AN D (•3) 30 / SIGN OF RESULT e .S9 "5/t,3 .. --- ALGEBRAI C SUM I AZI MU TH ( Zone B)( 29 ) AND (JO ) + " j_ /()o 1 ~1o; '177 j_ ~90~ 9.:19.!_ ~ COMPUTER CHECKER DATE SF<:. J. 'T. BONK c PJ. IHlEN 1 rEB 19- FOIIM DA 6-34 1 AUG 5» F igure 150. Completed DA F orm 6-94. AGO 10006A 249 values for lines 12 through 17 (a" a1 , b,, b"' This form, which is similar to DA Form 6-36, c, and c, ) are extracted directly from TM 5 also is designed for use with a computing ma 241-2, using the tables for the proper spheroid. chine. The procedure used for computations b. Formulas on which DA Form 6-34 is on DA Form 6-36 is used on DA form 6-34 based are shown on the back of the form. if a computing machine is not available. Also, AGO 10005A CHAPTER 17 QUALIFICATION TESTS FOR SURVEY SPECIALISTS 340. Purpose and Scope veyor. Section II expands the skill coverage This chapter describes the tests to be given for evaluating the qualifications of an individual in artillery survey. Section III is designed in the qualification of s urvey s pecialists at all echelons. Tests based on these outlines are deas a comprehensive coverage of the skills required in all echelons of artillery survey. signed to measure a soldier's skill in artillery survey. School training or a technical back ground is not required prior to taking these 343. Administration of Tests tests. Tests based on these outlines are de a. The tests based on these outlines are de signed to determine the relative proficiency of signed to provide for qualification of survey an individual artillery soldier in the perform specialists at all echelons. Because of organiance of duties as a member of a· survey section zational differences and differences in equip and are not designed as a basis for determin ment, some modification will be necessary for ing the relative proficiency of batteries or the administration of these tests to most units. higher units. These tests are also designed to The tests are designed where possible to facil serve as an incentive for individuals in sur itate this modification. Modification other than vey organization to expand their knowledge to those options presented in the tests should be cover all duties in the survey organization, accompanied by a reevaluation of the weight thereby increasing their value to the unit. ing system. 341. Preparation of Tests b. The battery commander will be responsible for the testing of personnel within his bat The tests will be prepared under the direc tery. Generally, tests will be administered as tion of the battalion commander, and should follows: consider the following: (1) An officer, warrant officer, or enlisted a. Tests should be standardized so that the man who is fully qualified and experi difference between test scores of any two indi enced in the subject covered by the viduals will be a valid measurement of differtest will be detailed as "examiner" toences in their skills. administer the test. b. Each crewman interested is a prospective ( 2) Each section of the qualification testscandidate and the tests should be available upon may be administrated over a periodhis request. of time that will be standardizedthroughout the battalion. 342. Test Organization (3) A single test, when started, will be The qualification test is organized into three conducted from start to finish without sections with each section designed to test and interruption. qualify the individual progressively as a second( 4) The candidate will receive no unauthclass specialist, a first-class specialist and as orized assistance. Assistance will bean expert in artillery survey. Section I is defurnished to the candidate as resigned to evaluate the qualification of the inquired for each test. If a candidatedividual in the basic skills of an artillery sur-fails any test because of the examiner AGO 1-0005A 251 or any assistant, the test will be dis345. Outline of Tests regarded and the candidate will be P a ra N_umber Points Maximum N o . Subject of tests each credit given another test of the same nature. (5) Times are not prescribed for each test SECTION I due to the different requirements of 346 4 -------6 Map Reading -------- units and because of varying effects Tests 1 and 2 ______ (2) 2 (4) Tests 3 and 4 ______ (2) 1 (2) of weather on the tests. However, the examiner should make appropriate 347 Recor ding ------------2 11 22 348 Comput ing -----------4 -------28 cuts when "excessive time" is taken (2) 5 (10) Tests 1 and 4 ---- to complete a portion of the tests. A (1) 8 (8) Test 2 ---------- decision by the responsible officer a s (1) 10 (10) Test 3 ---------- 1 20 20 to what constitutes "excessive time" 349 Taping --------------must be made prior to the administra350 Inst rument Oper a tion __ 2 12 24 tion of the tests, based on conditions 100 Total --------------------- existing a t that time. SECTION II (6) The examiner will explain to the can 40 Section I sco re X .40 -------------didate the scope of the test and indi2 10 20 351 Recording ----------- cate the men who will act as his assist 3 20 352 Computations ---------------ants. The examiner will critique the Tests 1 and 2 -----(2) 7 (14) candidate's performance at the com Test 3 -----------(1) 6 (6) 353 Instrumen t' Operation __ 3 -------20 pletion of the test and turn the ten (1) 8 (8) Test 1* ---------tative score in to the battery comTest 2 ------------(1) *8 (12) * (8)(12) mander. The battery commander will Test 3 ------------(1) *4 (8) *(4)(8) • When tellurometer or DME finalize the score and forward the test i s not issued to a unit T est score to the battalion. will be disregar ded and p o in value of Test 1 will be redis tributed as follows : T est 2, 12points; Test 3, 8 points. 344. Qalification Scores 100 Total ----------------------A maximum score of 100 is possible for each SECTION III section of the test. An individual must achieve Section II total X .50__ ------------50 a score of 90 percent on section I to be eligible 3 54 Map Re ading ---------1 -------5 to take section II. A score of 90 percent on 355 Grid Computations ----3 -------10 Tests 1 and 2 -----(2) 4 (8) section II is required prior to taking section (2) (1) 2 Test 3 ----------- III. 15 356 Survey Planning ------1 15 Points 357 Supervision and Individual clMaification 20 20Expert_______ __ ____ ___ __ __ __ ____ __ 90 on section III Operation ----------1 First-class specialist____ ______ ______85 on section II Total ----------------------100 Second-class specia!ist___ ______ __ ___ _85 on section I SECTION I (1) Topographic map, scale 1:50,000 or 346. Map Reading larger. a. Scope of Tests. Four tests will be conducted to determine the candidate's knowledge (2) Boxwood scale or coordinate scale, of map reading. protractor and map pins. b. Special Instructions. Prior to the start of (3) Military slide rule (if desired by can the test the examiner will provide the candi dates with the following equipment: didate). AGO 10005A 252 c. Outline of Tests. Test No. Examiner commands- Action of candidate 1 IDENTIFY THESE SIGNS AND SYMBOLS. (Ex- Identifies signs and symbols as they are pointed aminer points to 10 different commonly used mili out, orally or by writing answer. tary and topographic signs and symbols.) 2 COMPUTE THE SCALE OF THIS MAP. (Examiner Measures the map distance between the two points. designates two points on the map at least four Computes the scale using the map distance and inches apart, and gives the candidate a false ground distance between them.) the false ground distance. Announces or recordsthe result. 3 MEASURE THE GRID AZIMUTHFROM TO Measures the grid azimuth with the protractor. Announces or records results. (Examiner points out two prominent points on map at least four inches apart.) 4 DETERMINE COORDINATES AND HEIGHT Reads coordinates of designated point and deterOF -------------------------mines h eight. Announces or records results.(Examiner points out or designates arbitrary feature on map. Advise candidate to read coordinatesand height as accurately as possible.) d. Penalties. 347. Recording (1) Test 1. Deduct 0.2 point for each sym a. Scope of T es t. Two tests will be conducted bol or sign identified incorrectly. to determine the candidate's knowledge of re (2) Test 2 . Deduct 1 point if the denomcording. The first test will check proceduresinator of the representative fraction used with the aiming circle and the second testis in error by more than 100 units will be on procedures for the basic survey inand deduct all credit if in error by strument authorized by TOE. more than 200 units. b. Special Instr-uctions. Prior to the start of (3) Test 3. Deduct 0.5 point if the azithe test the examiner will make the followingpreparations: muth is in error by more than 5 mils and 1 point if in error by over 10 mils. (1) Provide equipment as listed below: (a) Blank mimeographed sheets from (4) Test .!,.. recorder's notebook. (a) Deduct 0.6 point if either the east(b) 4H and 6H pencil. ing or northing coordinate is in (c) Straightedge. error by over 50 meters. (2) Prepare the data so the examiner canread angles and distances, etc., in the (b) Deduct 0.4 point if the height is in same manner as a recorder would error by more than one-half of the receive the data if he were accomcontour interval of the map. panying a survey team in the field.Prepare a rough sketch of the area e. Credit. Subject to the penalties assessed to permit the candidate to complete in d above, credit will be awarded as indicated the remarks and sketch portion of the in paragraph 345. field notes. c. Outline of Tests. Test No. Examiner commands- Action of candidate 1 RECORD DATA FOR AIMING CIRCLE TRA-Records data as prescribed in chapter 7. Turns in VERSE. field notes to examiner at completion of the test. (Examiner reads data in same manner as normally available to recorder.) AGO 10006A 253 .__ _ ___ --- Test Action of candidate Examiner commands- No. Records data as prescribed in chapter 7. Turns inRECORD DATA FOR THEODOLITE TRAVERSE. 2 field notes to examiner at completion of the test. (Examiner reads data in same manner as normally available to recorder. Include at least one multiple angle. Triangulation or astronomic observation are authorized substitutions.) d. Penalties. Penalties will be assessed as 348. Computing follows: a. Scope of Tests. Four tests will be con (1) Failure to use proper procedure for ducted to determine the candidate's knowledge and ability to solve various survey problems. recording horizontal or vertical an gles, 3 points. b. Special Instructions. Prior to the start of (2) Failure to mean angles correctly, 3 the tests the examiner will make the following points. preparations: ( 1) Provide the following equipment:(3) Incomplete or incorrect remarks sec(a) One set of logarithmic tables (sixtion, 1 point. or seven-place as appropriate) for (4) Failure to record data in a neat and each candidate. legible manner, 10 points. (b) DA Forms 6-1, 6-2, 6-8, 6-19. (5) Any other procedural error, 3 points. (2) Prepare simulated or actual field data for all tests in the format prescribed e. C1·edit. Subject to the penalties assessed in d above, credit will be awarded as indifor the recorder's field notebook. Read or issue copy of data to the candidate. cated in paragraph 345. c. Outline of Tests. Test Action of candidate Examiner commands-No. 1 COMPUTE THE AZIMUTH AND DISTANCE Computes azimuth and distance with DA Form FROM POINT A TO POINT B. (Furnish coordi6-1. nates of each point.) Computes coordinates of each station on DA Form 2 COMPUTE THE FOLLOWING TRAVERSE: COM6-2. Computes accuracy ratio: azimuth error of PUTE ACCURACY RATIO AND AZIMUTH ERROR OF CLOSURE. (Provide coordinates of closure. starting point and azimuth to azimuth mark. Fur nish angles and distance in the same manner in which a computer would normally receive this infor mation. Provide coordinates of closing point and azimuth to azimuth mark if different than starting point.) Uses field data provided and DA Form 6-8 to solve 3 COMPUTE THE FOLLOWING TRIANGLE CHAIN. (Provide starting data and simulated or actual field triangle chain. work to enable candidate to solve the triangulation problem. Data should be made avail'able in the same sequence as normally provided to the computer by a survey party in the field.) Records field data on DA Form 6-19 and computes 4 COMPUTE THE FOLLOWING THREE-POINT RESECTION TO DETERMINE COORDINATES coordinates and height of occupied station. AND HEIGHT OF THE OCCUPIED STATION. (Provide candidate with necessary valid field data to perform the computation.) AGO 10005A 254 d. Penalties. 349. Taping (1) Tests 1 and 3. Deduct a. Scope of Test. One test will be conducted (a) 0.5 point for each mathematical to determine the candidate's ability to funcerror. tion as a tapeman. (b) 1.0 point for each logarithmic error. b. Special Instructions. Prior to the start of (c) 3.0 points for each procedural error. the test the examiner will make the following (2) Test 2. Deduct-preparations : (a) 0.5 point for each mathematical (1) Provide equipment as listed below:error. (a) One 30-meter steel tape. (b) 1.0 point for each logarithmic error. (b) Two plumb bobs. (c) 3.0 points for each procedural error. (c) One set of eleven taping arrows. (d) Two taping knuckles. (d) 1.0 point if accuracy ratio is com (e) One handle, steel tape, tension 30puted incorrectly and 0.5 point if lbs. the azimuth error of closure is com (f) Two ranging poles w/ tripods. puted incorrectly. (2) Prepare a traverse course consisting (3) Test 4. Deduct of two stations, A and B. Determine (a.) 0.5 point for each mathematical the accurate distance between the two.error. Use terrain that will require breaking (b) 1.0 point for each logarithmic error. tape. Require candidate to tape both (c) 1.0 point for each procedural error. ways but change position from fronttapeman to rear tapeman on the re e. Credit. Subject to the penalties assessed turn run. Use a second candidate or in d above, credit will be awarded as indicated assistant examiner for the second in paragraph 345. tapeman. c. Outline o{ Test. Examiner commands- Action of candidate TAPE TRAVERSE LEG FROM A TO B AND Tapes traverse leg as prescribed in chapter 6. FROM B TO A TO A COMPARATIVE ACCUComputes comparative accuracy. RACY OF 1:5000. COMPUTE COMPARATIVE ACCURACY THE TWO TAPED DISTANCES. d. Penalties. A penalty of 3.0 points will be (8) Accuracy ratio below 1:5000. Accuassessed for each of the following errors: racy ratio below 1:3000, cut 10 (1) Failure to maintain correct tape tenpoints. sion. (9) Any other procedural error. (2) Failure to maintain the tape in a horie. Credit. Subject to the penalties assessedzontal position. in d above, credit will be awarded as indicated (3) Improper handling of the plumb bob. in paragraph 345. (4) Failure to aline front tapeman. (5) Errors in breaking tape. 350. Instrument Operation ( 6) Errors in recording distance. a. Scope of Test. Two tests will be conducted (7) Incorrect computation of accuracy to determine the candidate's ability to set upratio. and operate an aiming circle and the theodolite. AGO 10005A 255 (b) Theodolite w/ tripod. b. Special Instructions. Prior to the start of (2 ) Prepare stations as necessary and acthe test the examiner will make the following curately determine angles, distances,preparations : azimuths, etc., to be used as a check (1) Provide equipment as listed below: on accuracy. Provide an assistant ex (a) Aiming circle w/ tripod. aminer as recorder for all tests. c. Outline of Tests. Test Action of candidate No. Examiner commands- Sets up aiming circle and measures horizontal and1 MEASURE THE HORIZONTAL AND VERTICAL vertical angles as precribed in chapter 7. MeansANGLES AZ-MK-Bn SCP-TS 1 WITH THE the angles and announces the results. AIMING CIRCLE. (Designate the Bu SCP and identify the Az Mk and TS 1.) Sets up the theodolite and measures horizontal and2 MEASURE THE HORIZONTAL AND VERTICAL vertical angles as prescribed in chapter 7. Means ANGLES TS1-TS2-TS3 WITH THE THEODO the angles and announces the results. LITE. (Designate TS 2 as the occupied station of a traverse and identify the rear and forward sta tions.) (b) Deduct 2.0 points for each proce d. Penalties. dural error in the angle measure (1) Test 1. Deduct ment. (a) 3.0 points for improper setup, level(c) For accuracy of measurement ofing or handling of the instrument. horizontal and vertical angles, cut(b) 2.0 points for each procedural error as ipdicated:in the angle measurement. (c) 4.0 points if the horizontal or verT 2 ( 1 s ec ) T 2 (mils) Cut tical angle is in error by more than TI6 Less than 1.0 mil but less than 2.0 mils. 0.1 miL_. Less than 05"___ Less than 0.02 mil ____ 0.0 (d) 6.0 points if the horizontal or ver0.1-0.2 ____ 05"-15"________0.02-0.08 mil _________ .3.0 tical angle is in error by more than More than 2.0 mils. 0.2 mil __ More than 15" __ More than 0.08 miL___ 6.0 (2) Test 2. e. Credits. Subject to the penalties assessed in(a) Deduct 3.0 points for improper set d above, credit will be awarded as indicated in up, leveling or handling of the in paragraph 345. strument. SECTION II (Consists of 40 percent of the earned score from section I plus the score earned in paragraphs 351-353.) (1) Provide equipment as listed below : 351. Recording (a) Field notebook or mimeographed a. Scope of Tests. Two tests will be conpages. ducted to determine the candidate's ability to (b) 4H and 6H pencil. record triangulation field notes and an astro(c) Straightedge. nomic observation problem. (2) Prepare simulated or actual field data to present to candidate in the same b. Special Instructions. Prior to the start of manner as a recorder would normally the test the examiner will make the following receive this information. preparations: AGO lOOO ;; A 256 c. Outline of Tests. Test No. Examiner commands- Action of candidate 1 RECORD THE FOLLOWING TRIANGULATION Records survey field data as prescribed in chapSURVEY. (Present field data from triangulation ter 7.problem in the same sequence a recorder wouldnormally receive this data.) 2 RECORD . THE FOLLOWING ASTRONOMIC OB-Records field data from the astronomic observationSERVATION. (Present field data from the obser as prescribed in chapter 7. vation in the same sequence that a recorder would normally receive the data.) d. Penalties. Deduct-a computer. The first test is solving a triangle (1) 2.0 points for each angle or time by triiateration and the second is computingmeaned incorrectly. an azimuth from an astronomic observation. (2) 4.0 points for each procedural error. The third test is computing grid convergence (3) 4.0 points if field notes are not neat for a specific area. and legible. b. Special Instructions. e. Credit. Subject to the penalties assessed ( 1) Provide equipment as listed below:in d above, credit will be awarded as indicated (a) Logarithmic tables (seven place). in paragraph 345. (b) TM 6-300-(current year). (c) DA Forms 6-7a, 6-10, 6-10a or 352. Computing 6-11, and 6-20. a. Scope of T es ts. Three tests will be con(2) Prepare actual or simulated field dataducted to determine the candidate's ability as for each test. c. Outline of Tests. Test No. Examiner commands- Action of candidate 1 SOLVE THE FOLLOWING TRIANGLE BY TR~LATERATION. Records given data on DA Form 6-7a and solves THE KNOWN LENGTH OF f or interior angles. THE SIDES ARE: a b c DETERMINE THE SIZE OF EACH ANGLE. 2 COMPUTE GRID AZIMUTH BY ASTRONOMIC Cses fi eld data provided and DA Forms 6-10, OBSERVATION BY THE ALTITUDE (HOUR 6-10a or 6-11, and 6-20. Computes all three sets, ANGLE) METHOD OF THE SUN (STAR). (Promean se ts and rejects any set that variesvide data from three sets of observations. Furnish from the mean by more than the tolerance pregrid convergence to permit candidate to determine scribed in chapter 13. Applies grid convergence grid azimuth. ) to mean of at least two sets to get grid azimuth. 3 COMPUTE GRID CONVERGENCE Computes grid convergence. Uses DA Form 6-20GIVEN DATA : and TM 6-300-current year. STATION: Bn SCP LATITUDE: ____N(S) LONGITUDE: _ ___E(W) COORDINATES: AGO Hl005A 257 (1) Provide equipment as listed below: d. Penalties. Deduct 0.5 point for each math (a) One master and one remote telluro ematical error, 2.0 points for each logarithmic error and 4.0 points for each procedural error. meter unit or two DME units com plete with cables, tripods and bat e. Credit. Subject to the penalties assessed in teries. d above, credit will be awarded as indicated (b) One Surveying Instrument Azimuth in paragraph 345. Gyro Artillery complete with cont rol panel and power source. 353. Instrument Operation (c) One theodolite with tripod. a. Scope of Tests. Three tests will be con(d) DA Form 5-139 (Field Record and ducted to determine the candidate's ability to Computations -Tellurometer) or operate the tellurometer or DME and the surDA Form 2972 (Field Record and veying instrument azimuth gyro and one test Computations-DME). will be conducted to determine the candidate's ( e ) Logarithmic tables (seven place). perform theodolite adjustments. ability to (2) Provide an assistant examiner to op Units not issued the tellurometer or DME will erate the remote or responder unit. disregard Test 1. ( 3) Provide a recorder for tests 1 and 2. b. Special Instructions. Prior to the start of the test the examiner will make the following (4) Provide stations and azimuth marks as necessary to conduct tests 1 and 2. preparations: c. Outline of Tests. Test Action of candidate Examiner commands-No. Sets up the master or mea surer unit; instructs re1 MEASURE THE DISTANCE TS 2-TS 3 WITH mote or responder operator; measures distance. THE TELLUROMETER OR DME. (Stations must Resolves transit time and determines sea levelbe at least 152 meters apart. Require the candidate distance in meters using DA Form 5-139, or to operate master station or measurer and instruct DA Form 2972. remote operator. Remote or responder operator can , be another candidate or an assistant examiner. De lete this test for units not issued the telluromet er or DME. Redistribute credit to other two t ests.) MARK Set s up azimuth gyro and determines azimuth to 2 DETERMINE AZIMUTH TO AZIMUTH WITH THE SURVEYING INSTRUMENT AZIazimuth mark. Applies grid convergence to atMUTH GYRO ARTILLERY. (Identify orienting tain grid azimuth. station and azimuth mark. Provide grid conver gence to candidate. Determination of azimuth by astronomic observation is an authorized substitution.) Performs t ests and adjustments as prescribed in 3 PERFORM THE FOLLOWING TESTS AND AD- JUSTMENTS ON THE THEODOLITE: chapter 7. a. PLATE LEVEL. b. OPTICAL PLUMB. c. VERTICALITY (NOT APPLICABLE ON T-16.) d. HORIZONTAL COLLIMATION. e. VERTICAL COLLIMATION. ning the measurement are inade d. Penalties. quate. (1) Test 1. Deduct- (c) 3 points for each procedural error (a) 2 points for improper setup or hanin the measurement. dling of the instrument. (d) 2 points for each procedural error(b) 1 point if instructions by candidate in the computation. to remote operator prior to begin- AGO 10005A 258 (e) 0.5 point for each mathematical accuracies are the same as listed inerror in the computation. chapter 13 for astronomic observa {f) 3 points if the accuracy is less than tions.) 1:7,000 but more than 1:5,000 when (e) The penalty points in parenthesescompared to the previously deterin (a) through (d) above will bemined distance. applied when Test Number 1 is not (g) 6 points if the accuracy is less than given. 1 :5,000 when compared to the pre (3) Test 3. viously determined distance. (a) Deduct 1 (2) point for each test or (2) Test 2. adjustment that is not conducted as (a) Deduct 2 (3) points for improper prescribed in chapter 7. setup, leveling or handling of the (b) Deduct 1 (2) point if test and adinstrument. justments are not conducted in the (b) Deduct 3 (4) points for each prosequence specified in chapter 7 forcedural error in the azimuth measthe instrument used.urement. (c) The penalty points in parentheses in (c) Deduct 1 (2) point for each compu(a) and (b) above will be appliedtational error. when Test 1 is not given. (d) Deduct 6 (8) points if accuracy nore. Credit. Subject to the penalties assessed in mally required by candidate's unit d above, credit will be awarded as indicated inis not attained. (Specifications for paragraph 345. SECTION III (Consists of 50 percent of the earned score from section II plus the score earned in paragraphs 354-357). 354. Map Reading lowing preparations and provide equipment aslisted below : a. Scope of Tests. One test will be conducted to determine the candidate's ability to scale (1) Map 1:50,000 or larger. geographic coordinates from a map. (2) Straightedge. b. Special Instructions. Prior to the start of (3) Military slide rule (if desired by canthe tests the examiner will make the foldidate). c. Outline of Test. Test No. Examiner commands- Action of candidate 1 DETERMINE THE GEOGRAPHIC COORDINATES etermine geographic coordinates of designated OF TO THE point. NEAREST 30 SECONDS. d. Penalties. Deduct in d above, credit will be awarded as indicated (1) 2 points if easting or northing is in in paragraph 345. error by more than 30 seconds butless than 60 seconds. 355. Grid Computations (2) All credit if easting or northing is in a. Scop·e of Tests. Three tests will be conerror by more than 60 seconds. ducted to determine the candidate's knowledgeof detailed survey computations consisting of e. Credit. Subject to the penalties assessed I converting geographic coordinates to grid co- AGO 10005A 259 (b) DA Forms 6-1, 6-2, 6-23, 6-34,ordinates, zone to zone transformation, and 6--36. conversion to commc;m control. (c) Logarithmic tables (six-or seven b. Special Instructions. Prior to the start of place).the test the examiner will make the following (d) TM 5-241-2. preparations: (2) Prepare realistic requirements to (1) Provide equipment as listed below: issue as tests 1-3. Solve and check (a) TM 5-241 (as appropriate depend ing on spheroid involved). requirements. c. Outline of Tests. Tellt Action of candidate Examiner commands-No. FOLLOWING GEOGRAPHIC Converts geographic coordinates to grid. Uses DA 1 CONVERT THE Form 6-25 and TM 5-241-(3/ 1, 4/ 1, 5/1, 6/ 1COORDINATES TO GRID COORDINATES : and 7). ---" N (S) ___ " E (W) TRANSFORM THE FOLLOWING COORDINATES Converts coordinates from one zone to the other. 2 Uses DA Form 6-36 and TM 5-241-2. FROM ZONE TO ZONE ____ E N ___ _ TO Converts designated points of traverse to common 3 CONVERT THE FOLLOWING TRAVERSE THE COMMON GRID: ASSUMED DATA: grid. Uses DA Forms 6-1 and 6-2. COORDINATES BN SCP HEIGHT BN SCP ---------- AZIMUTH TO AZIMUTH MARK-------- KNOWN DATA (COMMON GRID): COORDINATES BN SCP - HEIGHT BN SCP --------- AZIMUTH TO AZIMUTJI MARK ---------(Require candidate to convert all or selected points of the traverse run with assumed data to the com mon grid.) 356. Survey Planning d. Penalties. (1) Tests 1 and 2. Deduct 0.2 point for a. Scop-e of Test. One practical test will be each mathematical error, 1 point for conducted to determine the candidate's ability each logarithmic error and 2 points to plan a survey. This test will include a brieffor each procedural error. in by the examiner, map reconnaissance, (2) Test 3. Deduct 0.2 for each matheground reconnaissance, and the survey order. matical error, 0.4 point each loga b. Sp·ecial Instruc.tions. Prior to the start of rithmic error and 0.5 point for each the test, the examiner will make the following procedural error. preparations : e. Credit. Subject to the penalties .assessed in d above, credit will be awarded as indicated (1) Provide an area in which a survey can be conducted. in paragraph 345. AGO 10005A 260 (2) Provide a 1 :50,000 map of the area. surveyed and restrictions on use of (3) Prepare a situation to include unit routes, transportation and radios.mission, time available, designation (4) Provide a vehicle and driver for theand general location of points to be candidate. c. Outline of Test. Examiner commands- Action of candidate PREPARE A SURVEY PLAN TO SUPPORT THE Makes a map reconnaissance to include plotting inUNIT'S MISSION. THE MISSION ASSIGNED IS AS stallations requiring control. Makes a detailed FOLLOWS: ground reconnaissance and formulates a plan. IsEXTEND SURVEY CONTROL TO THE FOLLOWING sues a survey order to the survey party (exam POINTS: ____ ----· YOU WILL HAVE ____ iner). HOURS TO COMPLETE THE SURVEY. THE FOL LOWING RESTRICTIONS ARE IN FORCE: d. Penalties. Deduct e. Credit. Subject to the penalties assessed in(1) 2 points if the survey plan is not d above, credit will be awarded as indicated insimple, timely or flexible. paragraph 345. (2) 5 points if the plan is not adaptable or if it does not provide for checks. 357. Supervision and Operation (3) 10 points if the plan cannot provide a. Scope of Test. The test will determine thesurvey control to the required accurcandidate's ability to organize and direct a suracy at all installations which require vey party.survey. (4) 5 points if the survey order is not adeb. Spec'ial Instructions. Prior to the start ofthe test the examiner will provide a survey quate to insure the mission is accom plished. party complete with equipment and personnel authorized by applicable TOE. (5) 3 points if equipment is not utilized to best advantage. c. Outline of Test. Examiner commands-Action of candidate ORGAN~E THE SURVEY PARTY AND EXECUTE Briefs members of the survey party. Directs andTHE PLANNED SURVEY. (After the survey has started supervises operation until completiO'll. Functions require the candidate to operate the instrument for at as instrument operator when directed. least one station.) d. Penalties. (2) Deduct 3 points if the instrument is (1) Deduct 2 points for any failure tonot set up, leveled and angles meas (a) Orient all personnel. ured as prescribed in chapter 7. (Ap (b) Initiate the survey as soon as posplicable only when the candidate issible. functioning as instrument operator.) (c) Display an aggressive attitude in (3) Deduct 3 points for each failure tosupervising the party while the sur(a) Provide computers with necessaryvey is in progress. data to begin computations. AGO 10005A 261 (g) Check results by plotting surveyed (b) Properly select traverse (triangu lation) stations. (c) Supervise the work of the computers by spot checking their azimuths, bearing angles, distances and coord inates. (d) Periodically verify the recorder's notes. (e) Check taping procedures. (f) Correct erratic procedures immediately on discovery. points on a map. (h) Supervise the instrument operator during theodolite, tellurometer, or surveying instrument azimuth gyro artillery operations. e. Credit. Subject to the penalties assessed in d above, credit will be awarded as indicated in paragraph 357. AGO 10005A APPENDIX I REFERENCES 1. Miscellaneous Publications AR 117-5 Military Mapping and Geodesy. AR 320-5 Dictionary of United States Army Terms. AR 320-50 Authorized Abbreviations and Brevity Codes. AR 600-20 Army Command Policy and Procedures. DA Pam 108-1 Index of Army Motion Pictures, Film Strips, Slides, and Phono-Recordings. DA Pam 310-series Military Publications Indexes. (as applicable) FM 6-10 Field Artillery Communications. FM 6-20-1 Field Artillery Tactics. FM 6-20-2 Field Artillery Techniques FM 6-40 Field Artillery Cannon Gunnery. FM 6-120 Field Artillery Target Acquisition Battalion and Batteries. FM 6-121 Field Artillery Target Acquisition. FM 6-122 Artillery Sound Ranging and F lash Ranging. FM 6-135 Adjustment of Artillery Fire by the Combat Soldier. FM 6-140 Field Artillery Cannon Battalions and Batteries. FM 21-5 Military Training. FM 21-6 Techniques of Military Instruction. FM 21-26 Map Reading. FM 21-30 Military Symbols. FM 21-31 Topographic Symbols. FM 30-5 Combat Intelligence. FM 44-1 US Army Air Defense Employment.FM 44-2 Light Antiaircraft Artillery (Automatic Weapons).FM 61-100 The Division.TM 5-231 Mapping Functions of the Corps of Engineers.TM 5-232 Elements of Surveying.TM 5-236 Surveying Tables and Graphs.TM 5-241-1 Grids and Grid References. TM 5-241-2 Universal Transverse Mercator Grid, Zone-to-Zone Transformation Tables. TM 5-241-3/ 1 Universal Transverse Mercator Grid Tables for Latitudes 0°-80° ; International Spheroid (Meters). Volume I, Transformation of Coordinates from Geographic to Grid.TM 5-241-3/ 2 Universal Transverse Mercator Grid Tables for Latitudes 0°-80°; International Sphe~oid (Meters) . Volume II, Transformation of Coordinatesfrom Grid to Geographic.TM 5-241-4/ 1 Universal Transverse Mercator Grid Tables for Latitudes 0° -80° ; Clarke1866 Spheroid (Meters). Volume I, Transformation of Coordinates from Geographic to Grid. AGO 10005A 263 TM 5-241-4/2 Universal Transverse Mercator Grid Tables for Latitudes 0°-80°; Clarke 1866 Spheroid (Meters). Volume II, Transformation of Coordinates ~ ~ from Grid to Geographic. TM 5-241-5/ 1 Universal Transverse Mercator Grid Tables for Latitudes 0°-80°, Bessel Spheroid (Meters). Volume I, Transformation of Coordinates from Geographic to Grid. TM 5-241-5/ 2 Universal Transverse Mercator Grid Tables for Latitudes 0°-80° ; Bessel Spheroid (Meters). Volume II, Transformation of Coordinates from Grid to Geographic. TM 5-241-6/ 1 Universal Transverse Mercator Grid Tables for Latitudes 0°-80°; Clarke 1880 Spheroid (Meters). Volume I, Transformation of Coordinates from Geographic to Grid. TM-5-241-6/ 2 Universal Transverse Mercator Grid Table for Latitudes 0°-80° ; Clarke 1880 Spheroid (Meters). Volume II, Transformation of Coordinates from Grid to Geographic. TM 5-241-7 Universal Transverse Mercator Grid Tables for 0°-45°. Everest Spheroid (Meters). Transformation of Coordinates from Geographic to Grid and from Grid to Geographic. TM 5-241-8 Universal Transverse Mercator Grid. TM 5-241-9 Universal Polar Stereographic Grid Tables for Latitudes 79 ° 30'-90° ; International Spheroid (Meters). Transformation of Coordinates from Geographic to Grid and from Grid to Geographic. TM 5-441 Topographic Surveying. TM 5-6675-200-15 Operator, Organizational Field and Depot Maintenance Manual, Theodolite, Wild T16. TM 5-6675-202-15 Operator, Organizational, Field and Depot Maintenance Manual, Tellurometer. TM 5-6675-203-15 Operator, Organizational, Field and Depot Maintenance Manual, Altimeter, Surveying. TM 5-6675-205-15 Operator, Organizational, Field and Depot Maintenance Manual, Theodolite, Wild T2, 0.002 Mil Graduation. TM 5-6675-207-15 Operator, Organizational, Field and Depot Maintenance Manual, Surveying Instrument, Azimuth; Gyro; Artillery (ABLE). TM 5-6675-213-15 Operator, Organizational Field and Depot Maintenance Manual, Theodolite, Wild T2, 1 Second Graduation. TM 5-9421 Altimeters, Surveying. TM 6-230 Logarithmic and Mathematical Tables. TM 6-231 Seven Place Logarithmic Tables. Slide Rule, Military, Field Artillery, With Case, 10-inch. TM 6-240 TM 6-300-( ) Army Ephemeris. (appropriate year) TM 9-1290-262-35 Field and Depot Maintenance Manual, Aiming Circle M2. TM 9-6166 Operator and Organizational Maintenance: Aiming Circle M2. Tellurometer Handbook, Tellurometer (PTV) Ltd, Cape Town, South Africa (issued with ~ach unit). Instruction Manual, EM 2171, for ABLE (Surveying Instrument, Azimuth, Gyro Artillery), Model XCZA System with Modified Electronic Package, Autonetics, North African Aviation, Inc. 2. DA Forms 5-72 Level, Transit, and General Survey Record Book. Field Record and Computations-Tellurometer. 5-139 AGO 10005A 264 6-1 Computation-Azimuth and Distance from Coordinates.6-2 Computation-Coordinates and Height from Azimuth, Distance, andVertical Angle.6-2b Computation-Trigonometric Heights.6-5 Record-Survey Control Point.6-7a Computation-Plane Triangle.6-8 Computation-Plane Triangle Coordinates and Height from One Side,Three Angles and Vertical Angles.6-10 Computation-Astronomic Azimuth by Hour-Angle Method, Sun.6-10a Computation-Astronomic Azimuth by Hour-Angle, Method, Star.6-11 Computation-Astronomic Azimuth by Altitude Method, Sun or Star.6-18 Computation-Coordinates and Height from Two-Point Resection.6-19 Computation-Coordinates and Height from Three-Point Resection.6-20 Computation-Convergence (Astronomic Azimuth to UTM Grid Azimuth).6-21 Computation and Instruction for Use with Star Identifier.6-22 Computation-Conversion UTM Grid Coordinates to Geographic Coordinates (Machine).6-23 Computation-Conversion Geographic Coordinates to UTM Grid Coordinates (Logarithms).6-25 Computation-Conversion Geographic Coordinates to UTM Grid Coordinates (Machine).6-27 Computation-Altimetric Height (Single-Base or Leapfrog Method).6-34 Zone to Zone UTM Grid Azimuth Transformation. 6-36 Zone to Zone UTM Grid Coordinates Transformation. 2973 Fifth-Order Astronomic Azimuth Computation. 2972 Field Record and Computations-DME. 3. Other U.S. Government Publications The following publications are available from the Superintendent of Documents, U.S. Government Printing Office, Washington, D.C. a. Department of Commerce. Coast and Geodetic Survey: Special Publication No. 225, Manual of Reconnaissance for Triangulation. Special Publication No. 234, Signal Building. Special Publication No. 237,Manual of Geodetic Triangulation. b. Department of the Navy. Naval Observatory: American Ephemeris and Nautical Almanac (published annually). Air Almanac (published annually). Hydrographic Office: H. 0. No. 205, Radio Time Signals (current series). 4. Standardization Agreements STANAG 2202 Map Conventional Signs. STANAG 2210 Trig (Lists of Geod'etic Data). STANAG 2211 Geodetic Datums, Spheroids, Grids, and Grid References. AGO 10005A 265 APPENDIX II SURVEY SPECIFICATIONS TRAVERSE* Fifth-order Fourth-order Requirement Adjusted____________ ___________ ___ __ __ )'es---------------------------------~0 1:1,000 Closing error (position) _______________Use smaller of y"""l[ or 1:3,000 ~ot to exceed (Height)--------------·v'K-------------------------------±2 meters O.lm x ~ (Azimuth) _____________ Use smaller of O.l!i v'N or 0.04m X ~ Station between azimuth checks not to exceed_______________ __ 25-----------------------------------~A Horizontal angles_____________________ ! position (1 D/ R) __________________ ! position (1 D/ R) Vertical angles___________ ___________! D/ R ______________________________. l D/ R Distance: Tape_____________________________ Double tape to a com-Single tape Check by pacing parative accuracy of 1:5,000 Tellurometer---------------------·2 coarse, 4 fine readings_____________ 2 coarse, 4 fine readings DME_________ ___ ______ ___________ Measure in both directions__________ _Measure in both directions Scale factor__ ___ __ _____ __ __ __________ Yes ___ -----------------------------~0 Horizontal and vertical angles recorded to___ _______________ 0.001 miL___________________________ Q.l mil Azimuth carried to_____ _______________O.OOl miL______________ __ ___________ O.l mil Vertical angles and bearing angles used in computations to______ --------------_______0.01 miL_---------------------------0.1 mil Easting and northing coordinates computed to_____________ O.Ol meter--------------------------0.1 meter Height computed to_______ _____ _______ 0.1 meter-----------------------· ---0.1 meter Log tables used_______________________7 place___ __ __ ___ __ __ ____ ____ ______ 6 place • Always closed; on second point aa first ehoiee, on starting point aa second ehoiee. Remarks: K = length of traverse in kilometers. ~ = number of main scheme angles in the traverse. m= mil. AGO 10005A 266 TRIANGULATION* INTERSECTION-RESECTION Requirement Fourth-order Fifth-order Adjusted_________ _____ _________ ------·Yes -------------------------_______ No (Position)*____________1.4 vK ___ ___ ___ __________________ l:1,000 Closing error (length) ________ ___ ____ 1 :3,000 -----------------------------1:1,000 Not to exceed (Height)--------------'/K_______ ____ _____ __ __ __ __ ______ ±2 meters (Azimuth) ____________ _ 0.1 rh vN or 0.04 di x N__ __________ o.ln{ x N Maximum 2:Rt_________ _____ __ ______ _ 200 --------------------------------NA Between bases______ __________________ (or not to exceed 5 figures) Azimuth check________________________ (Not to exceed 5 figures) (normally with base line check) Horizontal angles_______ ____ __________ 2 positions (2 D/ R) -----------------1 position (1 D/ R) Vertical angles_______________________ _! D/ R______________________________ l D/ R Base determination___ _______ ________l7,000_______ ______________________ 1 :3,000 Known coordinates________________ see para 227a (3) ___________________ See para 227a (3) Tape_____________________________ Double tape_________________________ Double tape Tellurometer----------------------2 coarse, 4 fine readings_____________ 2 coarse, 4 fine readings DME_____________________________ Measure in both directions___________ Measurc in both directions Horizontal and vertical angles recorded to_____________ _____ O.OOl miL___________________________ 0.1 mil Azimuth carried to___________________ 0.001 miL___ ___ __________ ______ _____ O.l mil Vertical angles and bearing angles used in computations to______ ---------_____ __ _____ 0.01 miL_____ ----------_____________0.1 mil Easting and Northing coordinates computed to____________ _0.01 meter_____ __ ________________ ___ 0.1 me ;er Height computed to__________ ____ _____ 0.1 meter________ ___ _______________ _ 0.1 me ter Log tables used__ _______________ ____ _ 7-place -----------------------------6-pla<:•Scale factor__________________________ _ Yes ________________________________ No Minimum distance angles_____________.400 mils_____ __________ ______ __ ____ _400 rm ,s Triangle closure______________________ Avg for scheme 0.05 mil per triangle; max per triangle 0.06 miL___________________ _______0.3 mil TRILATERATION Requirement Fourth-order Permissible figure _______ ____ ____ ______ ___ __ ___ ______ Quadrilateral. Desirable minimum side length_______________________ 5 kilometers. Minimum permissible angle__________________ __ ______ _ 400 mils. Height______ __________________________ _______________ Altimeter (0.1 meter). Azimuth____ __ __________ ____ __ __________ __ __ __ ________ Established at terminal point by gyro or astro.Distances--------------------------------------------· Measure in both -directions; comparative accuracy1:25,000. • Closed on known control if possible; if not, throu~rh use of len~rth cheeks· (para 229e). Remarks: K = length in kilometers. N number of stations for carrying azimuth. rlt = mil. AGO 10.005A 267 I Fourth-order Requirement At each corner the sum of the two small angles will be 4 Angle check_______ ______________________________ ____ compared with the large angle. The two must agree , within ± 0.2 mil. Azimuth carried_____________ __ __ ____ ________ _________ To 0.01 mil through angles which most nearly equal 1,000 mils. Positions carried (E and N) --------------------------To 0.01 meter through lines used for azimuth. Use angles from DA Form 6-7a or DA Form 6-2. Method used when______ ____ _______ __ __ _________ __ __ _ a. No maps are available, or b. visual line of sight does not exist between stations due to weather, distance, or obstruction. ASTRONOMIC OBSERVATIONS Fifth-orderFourth-order Requirement 1:3,000 1:1,000 1:500* Minimum number of sets to be 3 3 4 observed ---------------------0.15 mil 0.3 mil 0.3 milRejection limit ------------------ Number of sets that must re3 main and be remeaned ---------2 2 1 position 1 position 2 readings Horizontal angles --------------- 1 D/ R 1 D/ R 2 readings Vertical angles ----------------- Considered accuracy -------------0.15 mil 0.3 mil 0.3 mil • Specifications apply for determining a fifth-order a zimuth. If the direction is not to be extended from the line established by the ob servation. the rejection limit can be relaxed to 1.0 mil with a considered accuracy o f 1.0 miL AGO 10005A -~ , 268 APPENDIX Ill DUTIES OF SURVEY PERSONNEL 1. Survey Officer c. Orients party members on the survey plan.The survey officer d. Supervises and coordinates the field op a. Coordinates and supervises the training eration of his survey party. of survey personnel. e. Maintains liaison with the survey officer b. Coordinates, supervises, and emphasizes or chief surveyor during field operations. the preventive maintenance program on sur f. Supervises preventive maintenance onvey equipment. section equipment, to include vehicles and com c. Coordinates, supervises, and establishes munications equipment. the survey information center (when the SIC g. Performs other duties as directed. is authorized at his echelon). d. Accompanies the commander on recon4. Survey Computer naissance. The survey computer e. Formulates and implements the survey a. Maintains the required DA forms for complans. putation of surveys. f. Supervises and coordinates the field operab. Performs independent computations durtion of survey parties under his jurisdiction. ing field operations. g. Advises the commander and staff on sur c. Performs other duties as directed. vey matters. h. Coordinates survey operations with sur 5. Instrument Operator vey officers of higher, lower, and adjacent headquarters. The instrument operator a. Performs preventive maintenance on the 2. Chief Surveyor authorized instruments. The chief surveyor b. Operates the instrument during field op a. Acts as the principal assistant to the surerations. vey officer and when directed performs any orall of the duties of the survey officer. c. Verifies the vertical alinement of therange pole before measuring angles during b. Supervises survey personnel in performfield operations. ance of routine reconnaissance, communica tions, and survey activities. d. Reads the measured values to the recorderand checks the recorder's operation by use of c. Performs other duties as directed. a read-back technique. 3. Chief of Survey Party e. Familiarizes himself with the fieldworkThe chief of survey party-requirements for all survey methods. a. Trains his survey party. f. Assists the tapemen in maintaining aline b. Implements his party's portion of the ment during taping operations. survey plan. g. Performs other duties as directed. AGO Hl005A 269 6. Recorder The recorder a. Maintains an approved notebook (DA Form 5-72, Level, Transit, and General Survey Record) or field book :record of all surveys performed by the survey party. b. Records survey starting data and all measured data with a 4-H pencil in a neat and legible manner during field operations. c. Sketches, in the approved notebook, complete descriptions of principal stations occupied during field survey operations. d. Checks, means, and adjusts angular data measured by the instrument operator. e. Checks taped distances by pacing. f. Provides required field data to the survey computers independently. g. Performs other duties as directed. 7. Tapeman The tapeman a. Maintains the fi're control set, artillery survey set, third (fourth) order. b. Tapes distances, using proper taping techniques, during field operations. c. Computes an accuracy ratio for taped distance when required. d. Reports measured distances to the recorder. e. Operates and maintains the section radio equipment. f. Performs other duties as directed. Note. The rea r tapeman commands the taping team. 8. Rodman The rodman a. Maintains the station marking equipment. b. Marks stations with hub and witness stakes during field operations. c. Centers and plumbs survey range poles over survey stations as required during field operations. d. Assists the tapeman in maintaining alinement of the tape. e. Operates and maintains the section radio equipment. f. Performs other duties as directed. AGO 10005A APPENDIX IV GLOSSARY OF ASTRONOMICAL TERMS a. The north and south celestial poles are the earth. This ecliptic intersects the celestial the points where the prolonged polar axis of equator at two points at an angle of 23lj2 °.the earth intersects the celestial sphere. i. The equinoxes are the two points where b. The celestial equator is the great circle on the ecliptic intersects the celestial equator. Thethe celestial sphere cut by the plane of the point where t he sun crosses the celestial equaearth's equator extended. A great circle is one tor from south to north is called the vernal whose plane passes through the center of a equinox or fir st point of Aries. The other pointsphere. is called the autumnal equino x and is diametric c. The zenith and nadir for any place on the ally opposite the first point. The equinoctialearth's surface are the two points where an expoints move slowly westward along the ecliptictension of the observer's plumbline intersects at a rate of about 50 seconds a year. As athe celestial sphere.The zenith is the point diresult, all the fixed stars gradually changerectly overhead, and the nadir is the point their positions with respect to the equator anddirectly underneath. the vernal equinox. d. The horizon for any place on the earth's j. The solstices are two points on the eclipticsurface is the great circle cut on the celestial midway between the equinoxes. When thesphere by the extension of the plane of the ecliptic is north of the celestial equator, theobserver's horizon. midpoint is called the summer solstice andoccurs about 21 June; when the ecliptic is south e. A vertical circle is any great circle on the of the celestial equator, the midpoint is called celestial sphere which passes through the the winter solstice and occurs about 21 Decemzenith. ber. It is easily seen, then, that the solstices f. The meridian of any observer is the great occur when the sun as at the greatest distancecircle on the celestial sphere which passes north or south of the equator. through the celestial poles and the observer's k. The lati tude of any place on the earth's zenith. surface is the angular distance of that place g. The prime vertical for any place on the from 0° to 90 ° north or south of the equator.earths' surface is the vertical circle perpendic l. The longi t·ude of any place on the earth's ular to the meridian. It intersects the horizon surface is the angular distance of that placeat the points directly east and west. from oo to 180 ° east or west of the meridian h. The ecliptic is the great circle cut on the of Greenwich which is used by most nationscelestial sphere by the plane of the earth's as the prime or initial meridian.orbit. If one could look past the sun and seethe stars, he would see the sun and stars m. An hour circle is any great circle on the celestial sphere that passes through the celesmoving slowly across the sky. The sun would tial poles. gain slightly on the stars each day. The earthis assumed to be stationary, and so the ecliptic n. The celestial coordinates are coordinates is assumed to be the path of the sun instead of used for locating a point on the celestial sphere. AGO 10005A 271 The coordinates used by the artillery are decobserver's position between the horizon and lination and right ascension. the body. t. The azimuth of a celestial body is theo. The dedina,tion of a celestial body is the angle at the zenith between the meridian of theangular distance from the celestial equator observer and the vertical circle of the body. Itmeasured along the hour circle of the body. is actually measured as an arc in the plane ofDeclination is given a positive sign when the the horizon and may be east or west of north. body is north of the celestial equator and a negative sign when the body is south. Declinau. The culmination or transit of a celestial tion coresponds to latitude on the earth. body is the passage of that body across the meridian of the observer. Every celestial body p. The right ascension of a celestial body is will have two culminations; passage across the the arc of the celestial equator measured from upper arc of the meridian is upper culminati on the vernal equinox eastward to the hour circle or upper transit, and passage across the lower of the body. It is measured in units of time arc is lo wer culmination or lower transit.from 0 to 24 hours. Right ascension corresponds to longitude on the earth. v. The elongations of a celestial body are two points in its apparent orbit at which the bear q. The hour angle of a celestial body is the ing from the observer's meridian is the great angle at the celestial poles between the plane of est. A star is said to be at easte1-n elongation the meridian of the observer and the plane of when its bearing is a maximum to the east and the hour circle of the star. Stated simply, the at western elongation when its bearing is a hour angle is the angle at the pole between the maximum to the west. observer's meridian and the meridian (hour w. The parallax of a celestial body is the circle) of the celestial body. This angle is sim difference in altitude of a body as seen from ilar to differences in longitude on the earth's the center of the earth and from a point on the surface. It is measured westward from the surface of the earth. There is no apparent observer's meridian. The hour angle is genparallax of the fixed stars, but that of the sun erally considered a1'\ an arc measured along the and planets is measurable. Parallax makes the celestial equator toward the west and may be body appear lower than it actually is; therefore expressed in time or arc. the correction is added. r. The polar distance of a celestial body is x. The r efraction of a celestial body is the the algebraic complement of the declination; apparent displacement of the body caused by the bending of light rays passing through laythat is, 90 ° minus a positive declination or 90 ° ers of air of varying density. The celestialplus a negative declination. body will appear higher than it really is; s. The altitude of a celestial body is the arc therefore, the correction is subtracted. A simple of its vertical circle measured from the horizon example of refraction can be noted by placing a spoon in a glass half full of water. to the body, or it is the vertical angle at the AGO tooosA 272 APPENDIX V STAR RATE INDEX TO USE THE PLATES: can be obtained from these stars using 1. Place the star identifier corres ponding to reasonable care. the observer's latitude over the plate in the c. A rea C. The rate is between 1.0 and 3.0.appendix. Stars within this area are the thirdmost desirable. Fifth-order azimuth can 2. Trace the curve for the rate desired, using be obtained from these stars using reas a sharp grease pencil. onable care. 3. The areas are marked on the plates as d. Ar·ea D. The rate is over 3.0. Stars withinfollows: this area should not be used; however,if they are used, the azimuth must be a. A rea A. The rate is between 0 and 0.5. determined by the hour-angle method. The dotted line indicates a rate of zero. Stars within this area are the most de 4. The area above 60 ° altitude is blank, as sirable for use in observations. Stars at stars in this area should not be used. higher altitudes are more difficult t o use. b. Area B. The rate is between 0.5 and 1.0. 5. Select stars that are within the area bestStars within this area are the second suited for the accuracy desired and will meetmost desirable. Fourth-order azimuth the tactical situation. AGO 10005A 273 AGO 1000 5A > Cl 0 0 0 0 "' 2'~I "'::IOIJTITAJ > LATITUDE 1S'N ~g ..., Plate 2. Star Rate Plate 1.5 ° ..... "" ..., ..... ()o LATITUOE 25"N 2cS 30UTITAJ & > C"l ... Plate 3. Star Rate Plate 25° 0 0 0 > ~ L:: 0 0.., ..., <:,) ...., <:l ~ ..., "' <:l 0::: ~ C"/.l ..; ...., "' <:l ~ AGO Hl005A z in .., w E .... :5 AGO 10005 A AGO 10005A AGO 10005A INDEX Paragraphs Page Accessories: Paragraphs Page Alinement, tape 80,83 33, 34Aiming circle M2 ------------147 76 Altimeter, surveying: Altimeter -------------------248 157 Care and maintenance _______ Azimuth gyro surveying 250 159 Comparison adjustment ______ instrument ----------------315 224 255 163Distance measuring equipment 123 58 Description -----------------247 156Taping _____________________76-92,93 General --------------------247 156 32,38Target set, surveying ______ __ 199 108 Individual instrumenttemperature correction ____ 254 T ellurometer ----------------101 41 162 Principles of operation ______ 246 Theodolite, T2 --------------175, 176 92 156 Reading the scales __________ 252 Theodolite, T16 -------------158 82 159 Relative humidity and air Accidental errors --------------96,98 40 temperature correction 256 165 Accuracy -----------------------App. II 266Astronomic observation ______ App. II 266 Altimetry: Comparative, of taped Computations ---------------260 167distances -----------------94 39 Methods --------------------251 159General --------------------App. II 266 Leapfrog ---------------258 165Intersection --------------;----232 148 Single-base -------------261 167Field artillery target acquisi-Angle: tion battalion survey ------40 16 Azimuth --------------------283 184 Traverse _________________213,app. II 124,266 Angles: Triangulation ---------------223, 225 132, 135 Determining with theodolite. App. II 266 (See Theodolite.) Trilateration ----------------App. II 266 Distance ___________________223i, 229b 133,142Adjustment: 230,234 144, 148Aiming circle --------------156 81 Horizontal ------------------150 78Angles, for triangle closure __ App. II 266 Measuring with:Theodolite T2 --------------188-194 102 Aiming circle. (SeeTheodolite T16 --------------169-174 90 Aiming circle.)Traverse (azimuth, coordi- Orienting -------------------22/ 8 nates, and height) _________ 214-218 126 Vertical --------------------151 78Aiming circle M2: Assumed data __________________196b,324b 106, 236Accessories -----------------147 76 Care and adjustment _______ _ Astro omic observations: 155, 156 80,81 Checking level line __________ Accuracy -------------------279-313 182 156 81 Checking level vial(s) _______ _ Azimuth: 156 81 Conversion ------------270 172Components ----------------146 72 Computations ---------------309-313 Declination -----------------273-276 176 200 Determining field data _____ _ 292-302 187 Leveling -------------------148c 77 Measuring: Measuring angles ----------296 188 Methods:Grid azimuths, with ____ _ 153 80 Horizontal angles _______ Altitude-hour angle ______ 307, 308, 195, 199, 150 78Vertical angles __________ 311 201 151 78 Setting up -----------------148 Altitude ----------------307, 308, 195, 199, 76Taking down --------------149 77 312 205 Hour angle _____________ 307, 308, Testing --------------------156 81 195, 199, Air defense artillery survey: 313 213 Polaris -----------------307, 308, 195, 199, AW battalions (batterie$) ___ _ 58 26 310 200 General ------------------ 57 25 Records of field data ________ 302 192Missile battalions ---------- 60, 61 26,27 Selection of computation Mission --------------------57 25 Surveillance radars _________ _ method -------------------307 195 59 26 Seleetion of star ------------304 193 AGO 10005A 281 Paragraphs Astronomic observations-Continued 304-306 295 Star identification Temperature --------------- 286-291 Time -----------------------Astronomic triangle (PZS) ______ 283 Azimuth: Adjustment -----------------216 Computed from coordinates ___ 267 Conver~on -----------------326 Determined by astronomic observation. (See Astronomic observations.) Grid -----------------------264, 270, 271 Magnetic -------------------265, 272 Transformation -------------335-339 True -----------------------263,270 Azimuth Gyro : 315 Accessories ----------------315 Description ----------------317-319 Operation ----------------- 322 Maintenance ---------------320 Recording ----------------- 318 Setting up ----------------- 321 Taking down ---------------- Base: Intersection ________________223d, 2231 Target area ----------------31,32 Triangulation _______________223d, 227 Battalion and battery survey, air defense artillery. (See Air defense artillery survey.) Battalion and battery survey, field artillery:Alternate positions __________ 19 12 Assumed data --------------Astronomic observation ______ 15 Connection survey ___________ 26,27 Converting to higher echelon 13 grid --------------------- 9General -------------------Operations: 16 Divisions --------------17 Sequence ---------------Limted time ____________ 20 Position rea survey ________ 21 18 Searchlight ---------------- Survey control: 14 Methods --------------- 10,11Points Target area : 28 Survey ----------------55 Battalion group --------------- 22a Battery center -----------------204 Bearing 96, 99 Blunders 87 Breaking tape Page 193 188 184 184 127 172 237 171, 172 171,175 246 171,172 224 224 226 23 5 231 226 235 132, 133 10, 11 132, 135 7 5 6 9 5 5 6 6 7 8 7 6 5 10 25 8 114 40 36 Paragraphs Celestial: Bodies ----------------------279,282 Simultaneous observations_ 277,278 Equator ------------------- 280 Meridian ----------------- 280 Sphere -------------------- 280 Triangle ------------------ 283 Center of impact registration ____ 33 Central point figures ____________224,230{ Chain of quadrilaterals __________ 224, 230 Chain of triangles ---------------224, 229 Char~ star ---------------------305 Chief of party _______________200,app. III Clamping handle ----------------84 Closed traverse ------------------197 Closure: Triangle --------------App. II Coarse alinement ----------------319 Coast and Geodetic Survey publications -------------------App. I Collimation adjustments: Theodolite ------------------172, 173, 192,193 Common grid __________________5, 323-328 Comparative accuracy of 94 taped distances --------------- Computations: 260 Altimetry ------------------Astronomic observations _____ 309-313 203-210 Coordinates Declination constant ________ 275 235 Intersection ----------------230 Quadrilaterals --------------Resection -------------------237, 239 Traverse -------------------203-213 Triangulation ---------------222-241 Computers ___________________200,app. III Connection survey ---------------26, 27 Control: Point, survey (SCP) _________ 47 196 Starting ------------------- 270 Convergence -------------------Conversion: Coordinates (see also Coordi nates, conversion): Geographic to grid ______ 333,334 Grid to geographic ______ 332 323-339 Survey control --------------To higher echelon control ____ 323-328 True azimuth to grid azimuth _ 270 Coordinates: 217 Adjustments ---------------323-334 Conversion ----------------329-334 Geographic ----------------335-339 Transformation ------------- Corps artillery survey. (See Target acquisition battalion survey.) Page 182, 183 177,180 182 182 182 184 12 133, 147 133,144 133, 142 194 110,269 35 107 266 229 263 91, 103, 104 3,236 39 167 200 113 176 148 144 151 113 132 110,269 9 19 106 172 242 242 236 236 172 128 236 241 246 AGO 10005A Paragraphs Corrections, altimetry ____________ 253-256 Critical points ------------------28-32 DA Forms. (See Forms, DA.) Data, assumed _________________196b, 324b Data, starting ------------------196 Declination: Aiming circle --------------275,276 Celestial body --------------282 Constant -------------------275 Magnetic disturbance ________ 273 Station ---------------------274 Department of Commerce publications ------------------App. I Department of Navy publications _ App. I Diagonals in quadrilaterals ______ 230 Directional traverse _____________197c, 268 Distance: Angles ____________________223i, 229b ·zao, 234 Computed: Coordinates -------------210 Tellurometer ____________ 110-117 Distance-measuring equipment (DME): Accessories -----------------123 Care and maintenance _______ 139 Computing ----------------130-135 Controls -------------------126 Description ----------------123 General -------------------122 Measuring -----------------129 Personnel -----------------136 Setting up -----------------127 Station selection -----------124 Traverse -------------------137 Division artillery survey: Accuracy __________________App. II, 35 General -------------------35 Operations ----------------39 Officer ---------------------36 SIC ------------------------37 Survey control --------------38 Easting -----------------------205 Engineer survey responsibilities __ 7 Error(s): Accidental ------------------96, 98 Caused by blunders __________ 96,99 Of closure, height __________ App. II Systematic ----------------96,97 Taping --------------------97,99 Traverse ------------------214,215 Triangle closure ------------223g Execution of survey order _______ 73 Factor, scale -------------------207 Factors affecting survey planning _ 63 AGO 10005A P a ge 161 10 106,236 106 176,177 183 176 176 176 263 263 144 107, 180 133, 142 144,148 116 52 58 66 65 59 58 58 63 66 61 59 66 266, 15 15 16 15 15 15 114 3 40 40 266 40 40 126, 127 133 30 115 28 Paragraphs F ield Artillery (FA): Battalion and battery. (See Battalion and battery survey.) Battalion-group. (See Bat talion-group.) Group. (See Group, field artillery.) Missile commands. (See Missile commands.) Target acquisition battalion. (See Target Acquisition.) Field notes: Astronomic observation ______ 302 General -------------------141 Intersection ---------------233 Notebook ------------------142-144 Resection ------------------241 Traverse ------------------202 Triangulation --------------227 Trilateration ----------------245 Fifth order --------------------App. II Fig res, strength ---------------224 Fine alinement ------------------319 Fine r eadings ------------------109, 112 Flash ranging observation post ___ 53 Forms, DA ---------------------App. I 5-139 ----------------------109 6-1 ------------------------210 6-2 ------------------------209 6-2b -----------------------212 6-5 ------------------------37,41 6-7a -----------------------245 6-8 ------------------------228d 6-10 -----------------------309,313 6-10a ----------------------309, 313 6-11 -----------------------309,312 6-18 -----------------------239 6-19 -----------------------237 6-20 -----------------------270 6-21 -----------------------306 6-22 -----------------------332 6-23 -----------------------333 6-25 -----------------------334 6-27 -----------------------260 6-34 -----------------------339 6-36 -----------------------337 2972 Field Record and Computation DME ________ 130-135 2973 Fifth-Order Astronomic Azimuth Computation ___309, 311-313 Forward : Line -----------------------230 Station ____________________79-83, 198 Fourth-order --------------------App. II Geographic coordinates __________ 329-334 Conversion to grid coordinates_ 333, 334 Grid: Azimuth -------------------264, 271 Common ___________________ 5,323-328 ConYergence ----------------270 Page 192 68 148 68 151 113 135 154 266 133 229 50,52 24 263 50 116 116 124 15, 16 154 138 200,213 200,213 200,205 151 151 172 195 242 242 242 167 247 247 65, 66 200,201 144 32,107 266 241 242 171,172 3, 236 172 P aragraphs P ageParagraphs Page 68 30 Magnetic: Ground reconnaissance ----------- 72 25 Needle ---------------------146 Group, field artillery ------------54 Objects affecting ________ 273, 274 176 Gyro azimuth surveying instru-North ----------------------272 175 ment . (See azimuth gyro.) Measuring:Angles. (See Angles. ) Height: Distances. (See Taping.) 218 129 Adjustment ----------------Meridians of longitude ________ __ 282 183 Computations: 14 6 167 Methods, survey, use ------------- Altimetric --------------260 Difference in (dH) ______ 208,218 116, 129 Missile command survey: Air transportable -----------56 25 Error of closure of _____ App. II 266 57 25Of instrument (HI) ________ _ 151, 164 78,88 Mission, air defense artillery _____ 5, 62 3,28 Mission, surve y ----------------- Trigonometric: 235 148 Nadir _______________________ 281, app. IV 183,271 Intersection ------------ Resection --------------237, 239 151 Naval observatory publications ___ App. I 263 116 Traverse --------------208 Night : 201 111228, 230 137, 144 Lights used with range pole __ Triangulation -----------38HI. (See Height of instrument Taping ---------------------92 205 114Northing, differ e nce in (dN) ___ __ (HI). ) 12 Notebook. (See Field notes.) High-burst registration ____ _____ _ 33 Notes, fi eld. (See Field notes. ) Horizontal angles: Observation:Determining with theodolite. Astronomic. (See Astronomic (See Theodolite.) observations.) Measuring with: Post(s) --------------------30 10 Aiming circle. (See Target area: Aiming circle M2.) 29b Azimuth mark ______ 10Horizontal scales. (See Scales, 10 Definition ----------30 reading.) Selection ___________ 30 10 32 Horizontal taping ---------------76-99 183 Observer's position --------------281Hour-angle method of astronomic 213 Occupied station ----------------198 107 observation -------------------313 197 107 271 Open traverse ------------------Hour circle ---------------------App. IV Operator, instrument ____________ App. III 269 Hydrographic Office publications __ App. I 263 Orienting: 195 22 8 Identifier, star ------------------306 Angle ----------------------Line -----------------------22 8 Instrument: 78,88 22 8 Height ---------------------151, 164 Point radar -----------------Operator -------------------App. III 269 Station ---------------------22 8 Intersection: Parallax -----------------------162 86 Accuracy ------------------App. II 266 Party, traverse -----------------200 110 235 148 Pins, taping. (See Taping pins.) Computations --------------231 148 Plan, survey. (See Survey plan.) Definition ------------------ Field notes ----------------233 148 Planning, survey. (See Survey 234 148 planning.)Limitations ----------------App. II 266 Plate levels _________________158c(1), 170, 82, 90,Techniques -----------------176c(2),189 94, 102 Latitude, paralJels --------------282 183 Plumb bob: Law of sines -------------------228 137 Used in taping --------------76, 80, 32, 33, 34, 35,Leapfrog altimetry --------------258 165 81, 85, 36,37,38 86,89,90 195 106 Legs, traverse 148 76 Used with aiming circle M2 Level: Used with theodolite ________159c, 177c 85,95 For range pole ------------199 108 107, 111, Pointings -----------------------198, 201, Plate. (See Plate levels.) 296-299 188 199 108 Leveling: Pole, range --------------------Altimetric ( see also Altimetry) 260 167 Poles, north and south celestial __ 280 182 The aiming circle M2 __ ____ _ 148 76 Position: 85,95 8 The theodolite --------------159,177 Area survey ----------------21-25 32 Lights used on range pole ______ _ 201 111 Determination --------------76-261 41 16 Taken with theodolite. (See L~~ trig ---------------------- 282 183 Theodolite.) Longitude, meridians AGO 10005A 284 Paragraphs P a ge Standing operating procedure (SOP) -----------------------74 31 Psychrometer -------------------248,256 157, 165 Star: Publications ______ ------------__ App. I 263PZS triangle -------------------283 184 Chart ----------------------305 194Identification ---------------304, 305 193, 194Quadrants ----------------------204 114 I de ntifier -------------------306 195Quadrilaterals ------------------224, 230 133, 144 Starting:Control ____________________10-13,27R1 and R2 chains ---------------224, 230 133, 144 5,9 Data, traverse --------------196 106 Radar: Station: Orienting point --------------22 8 Declination ----------------- Surveying for --------------25 9 274 176 F orward. (See Forward Radio time signals ------------- 288 185 station.) Ratio, accuracy, traverse ______213, app. II 124,266 Occupied. (See Occupied Rear station --------------------107 198 station.) Reciprocal measurements of Orienting -~----------------22 vertical angles ---------------211 117 8 Rear. (See Rear station.) Reconnaissance -----------------67,68 29,30 Recorder (See also Recording) __ _ Signals --------------------199 108 App. II 266 Recording (See also Recorder) __ _ Traverse -------------------199 108 142-144 68Reference stake ----------------199 108 Strength of figures -------------229 142 References --------------------App. I 263 Surveillance radar --------------59 26Refraction ---------------------294 188 Survey:Registration point --------------22,33 8, 12 Cont rol ---------------------10-13 5Repair, tape --------------------78 32 Information cente r SIC _____ _ 37,41 15, 16Resection: ~ethods -------------------14 6Accuracy -------------------App. II 266 ~ission -------------------5,62 3,28Computations ---------------237, 239 151 Orde r ---------------------70 30Definition ------------------236 148 Planning: Field notes -----------------241 151 Factors affecting _______ _ 63 28Limitations -----------------240 151 Steps in survey planning _ 65-69 29Techniques -----------------App. II 266 Purpose -------------------5 3Three-point -----------------236 148 Standing operating procedure _ 74 31Two-point ------------------238 151 Station, traverse ----------------199 108Restrictions on survey operations_ 63 28 Signals --------------------199 108 Right ascension (RA) ____ _____ 282, app. IV 183,271 Surveying: Rodman ------------------------App. III 269 Altimeter. (See Altimeter, Scale factor --------------------surveying.) 207 115 Scales, reading: For s. (See Forms, DA.) Aiming circle ---------------146 72 Swinging the grid --------------326 237Altimeter -------------------252 161 Systematic errors ---------------96, 97 40Theodolite T2 _______________ 180, 181 97,98 Theodolite T16 ___________161, 163, 164 85,86,88 Tables, logarithmic App. II 266 Schemes of traingle --------------224, 229 133,142 Tape: SCP. (See Survey control point.) Searchlight units ----------------Alinement -----------------83 34 18 7 Breaking -------------------87 SIC. (See Survey information Lengths, measuring _________ _ 36 center.) 80,81 33,34 Repair ---------------------78 32 Signs of dE and dN ------------205 114Silica gel -----------------------250 Tapeman -----------------------App. III 269 159 Simultaneous observation _______ _ 277,278 177,180 Tapes:Sines, law ---------------------228 137 Care 77 32 Single-base altimetry ____ ____ ___ _ 261 167 Description -----------------76 32 Single triangles, chain _________ _ 229 142Sketch ------------------------142-144 68 Taping ------------------------76-99 32 Sliding the grid ----------------325 237 Accessories ----------------76 32 Alinement ----------------- SOP. (See Standing operating 83 34 Errors --------------------97-99 procedures.) 40Night ---------------------92 38 Spherical triangle --------------283 184 Notes --··-------------------202 113 Stake, reference ----------------199 108 Pins -----------------------93 38 AGO 10005A 285 Paragraphs Page Paragraphs P a ge Traverse: Target acquisition, field artillery, Accuracy ___________ ______ 213,app.II 124,266 battalion survey: 124 16 Ratio ------------------ 213 40 Accuracy ------------------ 126 Adjustment -----------------214-218 Coordination and supervision _ 43 19 113 Computations ---------------203-21040 16 General --------------------· 106 44 19 Definition -------------------195 Operations ---------------- 107,172 Directional -----------------197, 268 42 18 Personnel ------------------ 66 40,41 16 DME ----------------------137 Responsibility -------------- 113 Field notes ----------------- Survey control points ________ 47 19 202 Isolation of error ___________ 219-221 129 Survey information center 111 41 16 Night ----------------------201 (SIC) -------------------- 110 41 16 Party ----------------------200 Time ----------------------- 115 Scale factor ----------------207 Target area: Starting control -------------196 106 31 10 Base, survey ---------------Stations _____ ---------------199 108 28-34 10 Survey --------------------Techniques -----------------App. II 266 57 Temperature : T ellurometer ----------------119 Astronomic observations _____ 295 188 107 Types ---------------------- 197 Corrections, altimetry ________ 256 165 Triangle, astronomic (PZS) ______ 283 184 266 132,266 Triangle, error of closure ______223, app. II Techniques --------------------- App. II 142Triangles, chain of --------------229Tell urometer: 100 40 Triangulation: Accessories -----------------Accuracy _____________223-225, app. II 132,266Computing a distance ______ 110-117 52 132101 41 Definition ------------------222 Description ---------------- Error of closure __________223, app. II 132,266102 42 Field notes ---------------- 133, 144 100 40 Quadrilaterals --------------224, 230 General -------------------135121 58 Reconnaissance --------------226Maintenance ---------------133 Measuring a distance ________ 109 50 Schemes --------------------224 135 Monitoring controls __________ 105 45 Single triangles -------------227-229 Strength of figures __________ 224 133 Operating controls __________ 105 45 118 57 Trig: Personnel ------------------ 16 Preset controls -------------105 45 List ------------------------41 103 42 Principles of operation -----Trilateration: 106 47 Computations ---------------245 154 Setting up ----------------- 182, 185 98, 102 154 Vertical angles ------------- Definition -------------------242 154 Employment ---------------- 243 Theodolite T2 (Sexagesimal): 154 188-194 102 Limitations -----------------244Adjustments --------------- 98 108 Circle reading -------------- 181 Tripod, ranging pole -------------199 175 92 171 Description -----------------True azimuth -------------------263 Horizontal angles __________ _ 184 99 Two-point resection. (See181 98Reading scales -------------Resection.) 185 102Vertical angles ------------- Vernal equinox _______________ 280, app. IV 182,271 Theodolite T16: 158e 84 Vertical angle correction (VAC) _ 152 79 Accessories ----------------- Adjusting for parallax ______ 162 86 Vertical angles:169-174 90 Adjustments ---------------Determining, with theodolite. Care and maintenance _______ 166-168 89 (See Theodolite.) 161 85 Circle reading ------------- Measuring, with: 157,158 82 Description ----------------Aiming circle. (See Aim 163,165 86,89 Horizontal angles ----------ing circle M2.)159 85 Reciprocal measuring ________ 211 117 Setting up ----------------- 164,165 88,89 Vertical angles ------------- Vertical scales. (See Scales,248 157 Thermometers in psychrometer reading.) Three-point section. (See 8 Weapons position, field artillery 24 Resection.) 184 Weather: Considerations in altimetry __ _ Time --------------------------- 286-291 249 158 Transformation, azimuth and 246 Effects of, on survey operations 63 28 coordinates -------------------335-339 Zenith _______________________281,app.IV 183,271 Transit time _________________ 103, 114, 115 42, 55, 56 Zone to zone transformation _____ 335-339 246 Transmission of direction ________ 277, 278 177, 180 AGO 10005A By Order of the Secretary of the Army: Official: J. C. LAMBERT, Major General, United States Army, The Adjutant General. Distribution: Active Army: DCSPER (2) ACSI (2) DCSOPS (2) DCSLOG (2) CORC (2) CRD (1) COA (1) CINFO (1) TIG (1) CNGB (2) CAR (2) USACDCARTYA (2) USCONARC (5) USACDC (2) ARADCOM (2) ARADCOM Rgn (1) OS Maj Comd (2) LOGCOMD (1) NG: State AG (3); units-same as Active Army. HAROLD K. JOHNSON, General, United States Army, Chief of Staff. Armies (5) Corps (3) Corps Arty (3) Div (2) Div Arty (5) Bde (1) FA Gp (5) FA Bn (5) USATC (2) except USATC FA (5) USMA (2) Svc Colleges (2) Br Svc Sch (2) except USAABS (15) Units org under fol TOE: 6-37 (2) 6-575 (15) USAR: Units-same as Active Army except allowance is one copy to each unit. For explanation of abbreviations used, see AR 320-50. '{:(U.S. Government Printing Office: 1965-781·256/lOOOSA AGO 10005A 287 WORLD CHART .4h 23h _lli Zlh ZOh 911 9QO, ' ' I I I I I I ! +---~~· ' ' ' I ' ' ' ' I ' ' I ' I ' ' I 6h _5h 4h _3b_ ---+ ' ' I I I III I " I" I " " I "1 "I "1 "I "1"T"lTT I TT1' 2h I " ' ' I " " I " " I ~.,-T ,. 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