ATP-3-09-30 Observed Fires Download
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Target Location and Identification 28 September 2017 ATP 3-09.30 3-17 Determine a vertical shift, if significant. Determine an up or down shift if the difference between the observer altitude and the target altitude is significant (greater than or equal to 35 meters and expressed to the nearest 5 meters). Figure 3-11. Polar plot SHIFT FROM KNOWN POINT 3-68. This is the least preferred and most difficult method of target location. The observer may have one or more known points in the area of responsibility. These are readily identifiable points whose locations are both known by the observer and the FDC. The observer does not need a map to use this method; only needs a known point. The steps in locating a target by shift from a known point are: Identify the known point used to the FDC, for example, SHIFT KNOWN POINT 1. Determine the observer-target direction. This direction can be a grid azimuth expressed to the nearest 10 mils (the preferred method) or a cardinal direction. Examples are (grid azimuth) DIRECTION 4360 and (cardinal direction) DIRECTION, SOUTHWEST. Determine a lateral shift from the known point in meters to the new target. By determining the angular deviation from the observer-known point line to the observer-target line, a shift in meters can be determined by using the mil relation formula, W = R x m/ (see example in figure 3-12 on page 3-18).