ATP-3-09-30 Observed Fires Download
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Adjustment of Fire 28 September 2017 ATP 3-09.30 5-19 Figure 5-11. Example registration diagram, page 2 5-76. Deviation refinement is determined by adding the deviation spottings of the rounds establishing the two over and two short (this may include two, three, or four deviation spottings). Then divide the total of the deviation spottings by the number of rounds (two, three, or four) to get an average deviation. Express the result to the nearest mil. The average deviation multiplied by the observer-target factor equals the correction, which the observer expresses to the nearest 10 meters. Note. Express deviation spottings to the nearest whole number and deviation refinement corrections to the nearest 10 meters. 5-77. After the impact phase of a registration, the observer transmits refinement data to the FDC (for example, LEFT 20, DROP 10). Normally the observer commands RECORD AS REGISTRATION POINT. However, since artillery computer system uses only known points, the observer may be required to transmit RECORD AS KNOWN POINT. In either case, the FDC must send a message to observer (MTO) assigning a known point number to the registration point.