ATP-3-09-30 Observed Fires Download
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Adjustment of Fire 28 September 2017 ATP 3-09.30 5-9 DEVIATION 5-34. The distance, in meters, the burst is to be moved (right or left) is determined by multiplying the observer's deviation spotting in mils by the observer-target distance in thousands of meters (the observer- target factor). Express deviation corrections to the nearest 10 meters. A deviation correction of less than 30 meters is a minor deviation correction. The observer should not send minor deviation corrections to the fire direction center except as refinement data or in conduct of destruction missions. 5-35. Announce the computed deviation correction to the fire direction center as “LEFT” or “RIGHT” (deviation correction in meters). The correction is opposite the spotting (a left spotting would result in a correction to the right). RANGE 5-36. When making a range correction, the observer attempts to "add" or "drop" the adjusting round, along the observer-target line, from a previous burst onto the target. If the spotting was “SHORT”, will add; if the spotting was “OVER”, will drop. HEIGHT OF BURST 5-37. Use one gun in adjusting fuze time. The observer adjusts height of burst (after a 100 meter range bracket has been established by using fuze quick) to obtain a 20 meter height of burst in fire for effect. This is done by announcing a correction of “UP” or “DOWN” (so many meters). 5-38. If the spotting of the initial round is “GRAZE”, an automatic correction of “UP 40” is sent. If the round is an airburst, the height of burst of the round (in meters) is computed (height of burst spotting in mils above the adjusting point multiplied by the observer-target factor). The appropriate height of burst correction is given (to the nearest 5 meters) to obtain the desired 20 meter height of burst. 5-39. Enter the fire for effect phase only when a correct height of burst is reasonably assured. Therefore, do not begin the fire for effect phase when the spotting for the previous round “GRAZE” or the height of burst correction is greater than 40 meters. If the spotting for the initial rounds in fire for effect is “MIXED” the subsequent refinement includes the correction “UP 20.” TARGET DESCRIPTION 5-40. Send the target description before a control correction during immediate suppression missions and when attacking a new target without sending a new call for fire. MISSION TYPE AND METHOD OF CONTROL 5-41. If the observer wants to change the mission and method of control, the observer transmits the desired method of control (for example, ADJUST FIRE, FIRE FOR EFFECT, or AT MY COMMAND). If the current method of control includes AT MY COMMAND, the correction is CANCEL AT MY COMMAND. SPLASH 5-42. An observer may have difficulty identifying or observing the rounds. This may be because the observer has to stay down in a concealed position much of the time or because of other fire missions in the area. In any case, the observer may request assistance from the FDC by requesting SPLASH. The FDC informs the observer that the round is about to impact by announcing SPLASH 5 seconds before the round impacts. The observer may end splash by announcing CANCEL SPLASH.