ATP-3-09-30 Observed Fires Download
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Chapter 3 3-18 ATP 3-09.30 28 September 2017 Figure 3-12. Lateral shift Note. When shift of greater than 600 mils is required, the accuracy of computing the lateral shift decreases. Use another method of target location. 3-69. Determine a range change to the new target in relation to the known point. The observer must determine whether the target is at a greater or lesser distance than the known point. The lateral shift gives the observer a point on the observer-target line (T') assumed to be the same distance from the observer as the known point. If the target is farther away than the known point, the observer must add the estimated distance from T' to the target (see figure 3-13 A on page 3-19). If the target is closer than the known point, the observer must drop the estimated distance (see figure 3-13 B on page 3-19). Express the correction for a difference in distance between the known point and the target to the nearest 100 meters.