FM-3-09 Fire Support and Field Artillery Operations Download
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Denied, Degraded and Disrupted Operations 30 April 2020 FM 3-09 C-5 C-19. The observer can obtain an initial location by map-spot and compass, however, should refine the observation post location and the orientation of the laser rangefinder with more accurate means as soon as possible. If possible, observer location should be determined by survey. Lacking survey control, however, the observer has a variety of techniques available to self-locate. An observer should always use the most accurate means of self-location available that the situation permits in a D3SOE. C-20. In order to consistently determine an accurate target location, an observer: Must be prepared to observe with a map and compass. Must be able to determine an accurate target location through mensuration using current target location tools. Must be able to use terrain association and map analysis for self-locating procedures. Must be able to self-locate to within 10 meters (100 meters if degraded by lack of position locating systems or other navigational aids). Uses prominent terrain features to relate potential target areas to grid locations on a map. Makes a thorough study of terrain by drawing a terrain sketch (in a static location) and visibility diagram. Associates the direction in which the observer is looking with a direction line on the map. Ensures that a planned target is always a recognizable point on the ground (except "cannot observe" missions). This ensures that the observer can consistently find the target location. C-21. Observers sometimes use a fire support vehicle equipped with the Fire Support Surveillance Sensor (referred to as an FS3) to assist them in locating the target. Binoculars used in conjunction with the M2 magnetic compass are excellent devices to assist the observer in locating the target. In a GPS denied or degraded operation the fire support vehicles are equipped with an inertial location and navigation system that allow for accurate position and direction information even after movements over large amounts of terrain. C-22. The observer can also self-locate by using map spot, resection, or a one burst artillery round. The preferred method of self-location uses the most current digital forward entry device. For more information see ATP 3-09.30. ACCURATE FIRING UNIT LOCATION C-23. The FA commander is responsible for accurate firing unit location for all indirect fire weapon systems. The components of accurate firing unit location are position, direction, and altitude. Accuracy standards of 7.0 meters horizontal circular error probable of 3.0 meters vertical probable error and no more than 0.6 mil azimuth probable error are considered the minimums for firing and TA assets to achieve accurate unit location. (ATP 3-09.02). The most accurate available survey equipment and on-board navigation systems are the primary means to achieve the accuracy standards listed above. The FDC can also determine the grid location of each piece by using the reported direction, distance, and vertical angle for each piece from the aiming circle used to lay the battery. SURVEY C-24. Survey provides indirect fire platforms as well as target locating assets with a common position and direction (common grid). With the proliferation of GPS technology in conjunction with onboard navigation systems, desired location accuracy is easily attained. However, while the proliferation of these systems facilitates self-location, it places on the FA commander the additional responsibility to ensure that enough survey control points exist throughout the AO to maintain common grid. C-25. There is no longer a military occupational specialty dedicated solely to survey. This creates a need to train non-survey soldiers on how to operate the survey equipment. The commander designates the personnel to train and form the survey team. The survey team provides survey for the unit. The survey equipment is assigned to the FA BN. C-26. The field notes of any survey are the only original record of the survey that the survey party has once it leaves the field. Therefore, the field notebook must contain a complete record of all measurements made or determined during the progress of the survey. It should include complete sketches, descriptions, and