ATP-3-09-30 Observed Fires Download
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Chapter 3 3-12 ATP 3-09.30 28 September 2017 Set off the direction on the OF fan. Plot the observer-target direction on the OF fan by finding the two radial lines between which the observer-target direction falls and visually interpolating the determined direction. Set off the estimated distance to the target. Look out along this interpolated radial line at the estimated observer-target distance. This is the estimated target location. Use terrain association to refine distance. Compare the terrain near the target with the terrain of the estimated target location on the map. If they do not agree, search along the radial line until the terrain and the map match. Determine target location. Determining a grid location for the target is a natural extension knowing the determined observer-target direction and the refined distance. The observer plots the observer- target direction and distance to the target on the OF fan and reads the corresponding grid from the map. As an example in figure 3-7, the observer has determined that the target is at direction 0700 at a distance of 3,300 meters. The corresponding grid location on the map is 535268. The observer can further determine the target grid elevation by using the map contour intervals. Figure 3-7. Target location using the OF fan