ATP-3-09-12 Field Artillery Counterfire and Weapons Locating Radar Operations Download
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AN/TPQ-36 Weapons Locating Radar Systems Characteristics and Employment 26 October 2021 ATP 3-09.12 J-11 J-45. Several conditions must exist for the WLR to achieve a solution and provide a POO. First, the range to the projectile must be such that the radar beam strikes the object on the ascending branch of the trajectory. In hostile mode, the WLR will only detect objects on the ascending branch of their trajectory. The size and speed are critical when identifying an object in the hostile mode. Once the software identifies the object, it determines the trajectory of the object. The object must display a ballistic trajectory or the software rejects it. There must be sufficient time for the software to achieve a solution on a ballistic trajectory. The tracking time for the AN/TPQ-36 is 3-5 seconds. J-46. The WLR can only determine locations from objects presenting characteristics within the technical capabilities of the software. The object must pass through the detection area of the search sector. It is important to understand the detection area in which the WLR can detect an object. TARGET CLASSIFICATION J-47. The AN/TPQ-36 classifies acquisitions as three distinct target types: artillery, mortar, rocket, or missile. The target classifications generated by WLR for transmission to AFATDS are mortar, artillery, and rocket unknowns. The acquisition ranges for mortars are the same as the ranges for artillery. PROBABILITY OF LOCATION J-48. In general, the AN/TPQ-36 can locate up to ten simultaneously firing weapons with QEs greater than 300 mils without degradation in probability of location. This is true when no more than two projectiles are being tracked or new firings do not occur at ranges less than 6km, or greater than three-quarters of the specified range for a specific projectile type. When both of these conditions occur, the probability of location may decrease to a probability of detection no lower than 50%. Wind and rain do not degrade the performance of the WLR when the following conditions exist: Winds do not exceed 40 mph with gusts to 75 mph. Rain does not exceed 5 inches per hour with horizontal wind gusts of 40 mph. J-49. The probability of locating a cannon projectile is 85% or greater at ranges from 4 -30km when weapon QEs are greater than 200 mils at ranges less than 10km and 300 mils at ranges greater than 10km. The ranges vary depending on the size of the projectile. The range fan for detecting light cannon is from 4-20km over the entire search sector. For medium cannon, the range fan is from 4-25km over the center 1067 mils of the search sector and 4-20km over the outside sector of the search sectors. The range fan for heavy cannon is from 4-30km over the center 1067 mils of the search sector and 4-22km over the outside search sectors. Table J-2 shows the higher probability coverage areas for cannons.