ATP-3-09-02 Field Artillery Survey Download
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Improved Position Azimuth Determining System 16 February 2016 ATP 3-09.02 8-7 IPADS OR IPADS-G MAP MANAGER 8-16. IPADS or IPADS-G map manager allows the operator to prepare digital map files in the special format required when transferring to and from a laptop computer. Maps loaded are the ones to be used during survey operations. Note. To ensure a proper map display, boundaries for the entire operational area to be covered should be entered. IPADS or IPADS-G map manager will prepare as many maps are necessary to cover the area with the data available for the selected data blocks. Note. IPADS or IPADS-G map manager expects World Geodetic System (WGS) 84 coordinates referenced to another datum would not significantly impact map boundaries. ELLIPSOID AND DATUM 8-17. IPADS or IPADS-G can store two sets of user-defined datum parameters for each predefined ellipsoid and for each of two user-defined ellipsoids. Verify parameters are for the intended datum when selecting a user-defined datum. Incorrect parameters may introduce significant position error. 8-18. IPADS or IPADS-G must be configured for datum of initial update SCP. Ellipsoid and datum can be change later if output of coordinates on a different datum is required. Datums are associated with ellipsoids. IPADS accepts entry of user-defined ellipsoid and datum parameters. CAUTION Ellipsoid and datum can be changed at any point during a mission. Datum shifts have unknown associated errors. Do not initialize and close IPADS surveys at SCPs on different datums. SCPs on different datums probably were established by different, unconnected surveys. Closing at a SCP on a different datum may introduce significant error into adjusted coordinates. IMAGERY IPADS OR IPADS-G INITIALIZATION METHOD 8-19. If GPS, is not available the surveyor may use a technique using digital imagery precision strike suite–special operation forces (PSS-SOF) to establish an IPADS or IPADS-G initialization grid coordinate. This technique is only viable when the operator can determine a well-defined / distinguishable point Imagery (for example, (PSS-SOF) may be used to establish an initialization grid coordinate only. Due to the inherent circular error, imagery is not to be used to establish directional control. Establishing an initialization grid coordinate and uploading into IPADS or IPADS-G is acceptable. Direction is then established by IPADS or other manual/degraded methods (above). This method ensures a common grid coordinate is shared and disseminated throughout the area of operation. Note. The operator must ensure the reference point used is clearly distinguishable on the ground and on the imagery itself (for example, corner of a building, road intersections, or base of a water tower. Marking a stake in the middle of an open area (field) is not an acceptable method. 8-20. Refining a Position Using Imagery. FOS 11.01.03, PSS-SOF, and the digital point positioning data base imagery that shows local imagery should be loaded on your computer. A database should also be present that includes your current location, a member (subscriber) so you can simulate transmitting messages, and geometries.