ATP-3-09-02 Field Artillery Survey Download
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Survey Operations 16 February 2016 ATP 3-09.02 3-7 M777 SURVEY 3-32. The digital fire control system integrates modular components on the M777A2 howitzer. With its navigation subcomponents: The Inertial Navigation Unit (INU), Motion Velocity Sensor, Mission Support Computer and Dual DAGR GPS the digital fire control system provides: Gun location. Pointing. Navigation. Digital communications. Emplacement and displacement aid capability. 3-33. The INU located in the right gun carriage assembly (over the right wheel when howitzer is emplaced) provides weapons position, location, and current pointing data to the Mission Support computer. Using both a DAGR (in the Communications location assembly) and a vehicle motion velocity (located on the right wheel of the howitzer) it maintains navigation data. The INU determines weapons location in terms of Easting, Northing, and Altitude (meters), and cannon pointing information in terms of quadrant elevation and azimuth. PALADIN SURVEY NAVIGATION SYSTEM WITH MODULAR AZIMUTH POSITIONING SYSTEM 3-34. The modular azimuth positioning system (MAPS) is made up of modular components combined in different configurations to provide survey and orientation information needs of a particular system. In the Paladin application, major components of MAPS consist of the dynamic reference unit-hybrid, vehicle motion sensor, and the GPS DAGR. 3-35. The dynamic reference unit-hybrid is mounted on the right trunnion of the Paladin armament system. Operating in conjunction with PLGR, the dynamic reference unit-hybrid contains all necessary sensor electronics, processing, and input-output circuitry to perform survey and orientation functions and interface with other MAPS components. The dynamic reference unit-hybrid performs the following functions: Provides vehicle position from a known starting point in terms of universal transverse mercator coordinates of easting, northing, and altitude. Provides vehicle orientation in terms of azimuth from grid north. Compensates for weapon pitch and cant. Supplies angular velocity rates. Provides weapon elevation, grid azimuth, azimuth rate, elevation rate, travel local grid azimuth reference, and travel local elevation reference. Note. A best practice is for the section chief to copy down all position and direction data for his weapon system before he shuts down the computer. This enables the section chief to establish his own SCP to initialize his system when he powers the computer back up. PALADIN ELEMENT 3-36. The Paladin is the M109A6 self-propelled howitzer equipped with a MAPS. With MAPS, the Paladin has more flexibility and requires fewer crewmembers and less equipment. The Paladin battery normally operates in a two-platoon configuration (three howitzers per platoon). A Paladin platoon requires a position area on the order of 2,000 by 1,000 meters and it uses all of that terrain during normal operations. Limitations of the onboard navigational system restrict the howitzer displacement distance. The Paladin must be updated every 16 miles or 26 kilometers to ensure that it meets position accuracy requirements.