ATP-3-09-12 Field Artillery Counterfire and Weapons Locating Radar Operations Download
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Appendix H H-4 ATP 3-09.12 26 October 2021 the radar beams are being blocked by the foliage (screening crest) in front of the WLR. For this reason, it is important to place the trailer well back from trees in the direction of WLR search, if operation in a forest environment is required. The angle to the top of the nearest tree is the mask angle, ideally about 10 mils. H-13. The site can be camouflaged, but the camouflage must provide clearance for 360-degree antenna rotation. The camouflage for the ATG must be of a radar transparent type, while the camouflage for the OCS can be radar scattering. H-14. If other radar sets are operating in the area, consideration for WLR site location should be taken into account in order to minimize the common illumination volume between radar sets. H-15. When a site location has been selected, the site grid coordinates and a boresight reference have to be established and marked to properly orient the WLR during occupation. A fifth-order survey is required to determine the site grid coordinates. This survey is performed by a survey team prior to the arrival of the WLR set and will not be done by the installation team. When the position has been determined, it is marked by the primary stake (near stake). A near stake is not required if utilizing Inertial Navigation System or a Global Positioning System. H-16. For the boresight reference, a second stake (far stake) is preferably located more than 250m away in any convenient direction from the primary stake. A far stake is not required if utilizing Inertial Navigation System or a Global Positioning System. H-17. The minimum acceptable distance is 100m. The azimuth angle (AZ Ø) formed by the intersection of the line between the two stakes and grid north is then measured by the survey team. The measured azimuth, along with the site grid coordinates, is recorded for subsequent use during initialization of the weapons location program. PLANNING CONSIDERATIONS H-18. During planning the tactical position areas are selected based on IPB, the range capabilities of the WLR, and METT-TC. A complete analysis of METT-TC will dictate which factors are most important. Generally, WLRs are positioned far enough from the FLOT to acquire enemy weapons and to prevent loss of personnel and equipment to enemy action. While avoiding unnecessary moves supports maximizing coverage and cueing time this might not be possible in LSCO. H-19. The AN/TPQ-53 is usually located 8-12km behind the FLOT. The system was designed to detect acquisitions from 500m-60km. The AN/TPQ-53 has the flexibility to optimize coverage with a variety of operational modes and sub-modes. H-20. The AN/TPQ-53's are not intended to work independently, but as a system of systems providing a tactical capability to the force. This redundant capability allows for one system to provide coverage while the other system move, conduct maintenance or repair activities. Positioning may change based on the tactical situation. PROXIMITY OF OTHER WEAPONS LOCATING RADARS H-21. Other WLR systems or active emitters can interfere with WLR coverage by attenuating or jamming the WLR beam. WLRs and emitters in close proximity on a similar azimuth of search may cause jamming or false locations. Inadvertent jamming and false locations can be avoided by careful planning of WLR positions. H-22. The following positioning guidelines are provided to ensure non-degraded performance of the AN/TPQ-53 WLR systems when operating in close proximity: Two AN/TPQ-53 arrays operating in one of the 90 degree modes must be separated by 5km and facing in the same general direction with a maximum angle of 889 mils (50 degrees) formed by the intersection of the boresight axes of the 2 arrays. Each will electronically scan up to 800 mils (45 degrees) from their respective mechanical azimuth of search. Figure H-3, on page H-5, shows the geometric orientation of the two systems in close proximity. The systems should be operating on separate frequencies [25 megahertz (MHz) separation] and the transmitting and receiving systems will be.