ATP-3-09-02 Field Artillery Survey Download
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Chapter 7 7-10 ATP 3-09.02 16 February 2016 Requirements for 1:500 azimuth (±0.5 mil) are as follows: An azimuth of fifth-order or better and a NIKON NE-102 theodolite at the master station. An aiming circle at the flank station. Specifications are the same as for an astronomic observation (Appendix B). Station displacement (curvature) corrections must be applied (see Figure 7-4) 7-29. If the master station instrument is a NIKON NE-102 theodolite and the flank station instrument is an aiming circle, the maximum accuracy to be expected is ±0.5 mil. Note. Simultaneous observations will yield the same accuracy as astronomic azimuths taken with the instructions used to a maximum D value of approximately 26,000 meters. Observations may be conducted over much longer distances if a 1-mill or 2-mil accuracy is acceptable. HASTY ASTRONOMIC OBSERVATION 7-30. This method enables battalion surveyors and firing battery personnel to compute a grid azimuth and a check angle from observations of the sun or a selected survey star. The accuracy of the computation depends on which instrument is used to perform the observations. The fieldwork for this method is the same as the fieldwork for a flank station simultaneous observation. The procedures for hasty astronomic are listed below: Emplace the NIKON NE-102 over the orienting station. Place 0000.0 mils on the horizontal scale. Lock the scale with the horizontal clamp. Track the celestial body (with scale locked), and announce TRACKING when the instrument is oriented on the sun or selected survey star. Announce TIP when the center of the reticle is exactly aligned on the sun or star (see figure 7-6). At the announcement of TIP record the date and time of tip. Depress the telescope, and emplace the EOL. Unlock the scales, and repeat steps 3 and 4 (see Figure 7-4). Record all data on appropriate form and enter into the HTU. The HTU will display the check angle. Compare the check angle from the HTU to the check angle on the instrument. If the difference is ±2.0 mils for the aiming circle and ±0.3 mil for the NIKON NE-102 theodolite, the azimuth to the EOL displayed by the HTU is good; if not, check all data and/or reobserve. Figure 7-6. Announce telescope in place (TIP) CHOICE OF A CELESTIAL BODY 7-31. During daylight hours, the sun is the only celestial body that can be readily observed. At night, Polaris is one of the most easily identified stars in the Northern Hemisphere. It is ideal for observation