ATP-3-09-30 Observed Fires Download
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Chapter 3 3-14 ATP 3-09.30 28 September 2017 3-55. Normally, if the mission is a fire for effect mission, send a vertical shift to improve accuracy. The observer should weigh the time needed to determine and send a vertical shift against the time available. Experienced observers who can quickly determine differences in altitude should send a vertical shift when the difference in altitude is greater than or equal to 35 meters and express it to the nearest 5 meters. When responsiveness is paramount, inexperienced observers should not try to send a vertical shift. VERTICAL ANGLE 3-56. A vertical angle is the angle measured vertically, up or down, from a horizontal plane of reference and expressed in plus or minus in mils depending on whether the position is above or below the horizontal plane (TC 3-09.81). The vertical angle is normally expressed as a plus or minus depending on whether the line from the observer to the target is above (plus) or below (minus) the observer’s horizontal plane (see figure 3-9). Vertical angle (versus shift) is determined in laser polar missions with a leveled measuring laser designator and rangefinder. Figure 3-9. Vertical angle TERRAIN SKETCH 3-57. The terrain sketch is a panoramic sketch as accurate as possible of the terrain by the observer of the area of responsibility. It aids in target location in a static environment. The terrain sketch should include the following: The skyline (horizon). Intermediate crests, hills, and ridges. Other natural terrain features (distinctive bodies of water and vegetation). Manmade features (buildings, roads, power lines, towers, antennas, and battlefield debris). Labels (reference points and targets). 3-58. Each labeled item should include as much information as possible to aid the observer. Use a "T" format (see figure 3-10) to identify information. Place reference point names, target numbers, or known point (kn pt) designations at the top of the T to identify the feature. Place labels for direction (dir), distance (dis), altitude (alt), and grid on the left side of the T. The observer should fill in all available data for targets and known points. Reference points usually require only the direction to the reference point. Data should be determined to the left edge of the reference point, unless the target has been fired upon; then use the target center of mass. The terrain sketch should also include the observer's name, time, date, and location.