ATP-3-09-30 Observed Fires Download
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Appendix A A-2 ATP 3-09.30 28 September 2017 Example A24 (FDC) THIS IS A58 (OBS), TRILATERATION, OVER. KNOWN POINT CADDO, DIRECTION 1743, DISTANCE 1230, VERTICAL ANGLE PLUS 10, KNOWN POINT FLATTOP, DIRECTION 2338, DISTANCE 3180, VERTICAL ANGLE MINUS 10, OVER. KNOWN POINT CADDO ON LEFT, OVER. A58 (OBS) THIS IS A24 (FDC), LOCATION NK47253824, DIRECTION TO CADDO 1723, OVER. Figure A-1. Self-location by use of two known points SELF-LOCATION BY USE OF ONE KNOWN POINT AND ONE BURST A-3. If only one known point is available, the second point may be established by a planned burst of an HE or a WP round (see figure A-2 on page A-3). The observer should plan the location of the burst so that it is separated from the known point by at least 300 mils. Graze bursts should be used. Using the laser rangefinder, the observer ranges the known point and the burst of the round to determine the direction, distance, and vertical angle for each of the two points, and reports these to the FDC. The FDC computes the laser rangefinder location and corrected azimuth to the known point and sends the information to the observer. Note. The accuracy of the computed laser rangefinder location and the reference azimuth is affected by the accuracy of the firing data used to fire the round. The FDC should use the most accurate data available.