AN/APQ-116 is one of the most numerous terrain-following radars (TFRs) produced in the world, and with over 500 units built, it was a member of a family of TFRs consisted of nearly two dozen models, all of which are based on the same general design principle. First developed by Texas Instruments, and later produced by Raytheon when the latter purchased the radar business of the former.[1]
AN/APN-149
editThis is the first terrain-following radar for use on crewed aircraft, designed by Bert Bechtel, a former Navy engineer, who had designed a radar scan template control technique that permitted safe aircraft descent in adverse weather. The concept was the basis of winning a $750,000 US Army contract to develop a radar system to automatically guide a drone aircraft. The US Army did not pursue the project to production, but the US Air Force became interested and believed that Bechtel's innovation would protect the low-flying planes.[2]
AN/APN-165
editTerrain-following/ground-mapping radar by Texas Instruments for OV-1 Mohawk[1]
AN/APQ-89
editTFR (Terrain-Following Radar) tested on T-2 Buckeye for pilots to familiarize TFR operation on other combat aircraft.[1]
AN/APQ-99
editDeveloped by TI as a multi-modes radar,[2] in addition to terrain avoidance and terrain-following modes, and AN/APQ-99 can also be used for ground mapping. Smaller in size then the Westinghouse AN/APQ-72 and fitted in the nose of for A-7A, RF-4B/C. AN/APQ-99 is also supplied to Germany, Iran and Japan.
AN/APQ-101
editTerrain-following radar by Texas Instruments.[1]
AN/APQ-110
editKu band terrain-following radar by Texas Instruments for General Dynamics F-111A and RF-4C. It replaced the side-looking mapping radar by Goodyear Tire and Rubber Company on RF-4C.[1]
AN/APQ-115
editImproved AN/APQ-110 terrain-following radar by Texas Instruments for the A-7A, General Dynamics F-111, RF-4C, and C-130E. AN/APQ-115 has a single contoured, spoiled parabola antenna, with a search cone of 5 degrees wide, spanning from +7 degrees above to -18 degrees below to the boresight of the aircraft. AN/APQ-115 suffered from inaccurate references (poor stabilization and Doppler inputs), which directly lead to the development of more advanced system such as AN/APQ-122.[3]
The Texas Instruments I-band AN/APQ-116 is a TFR used in A-7 Corsair II[1] and C-130 Hercules aircraft. AN/APQ-116 was basically the integration of previously independent AN/APQ-115 TFR into the ILAAS digital navigation system. The radar also fed a digital weapons computer which made possible accurate delivery of bombs from a greater stand-off distance, greatly improving survivability compared with faster platforms such as the F-4 Phantom II.
AN/APQ-122
editX band multi-mode radar by Texas Instruments for C-130 Hercules, Boeing RC-135, Boeing T-43 and Boeing E-4. AN/APQ-122 has a slotted planar array antenna with a separate X-band receiver used to generate MRI video, with a search cone of 7.5 degrees wide, spanning from +8 degrees above to -17 degrees below to the boresight of the aircraft. For AN/APQ-122(V)B, the stabilization reference could either be manually or automatically switched to MD-1 gyro if the LN-15J inertial navigational system become unreliable or inoperable, thus terrain following operation can still continue, where in earlier system such as AN/APQ-115, if the Doppler fails, the terrain following operation would be discontinued.[1]
AN/APQ-126
edit60 kW improved AN/APQ-116 J band terrain-following radar by Texas Instruments for A-7D/E AC-130 and CH-53 Sea Stallion.[4] This is primarily AN/APQ-116/122 incorporating improved maritime capability. Specifications:[5]
- Maritime surface search: (high altitude): 150NM
- Maritime surface search: (low altitude): 106NM
- Maritime surface search (vs. small contacts): 51NM
- Land surface search (med altitude): 34NM
- Air search: 20NM
- Terrain following: 19NM
AN/APQ-134
editKu band terrain-following radar by Texas Instruments to replace AN/APQ-110 for F-111A/FB-111A.[1]
AN/APQ-139
editKu band multi-mode radar by Texas Instruments for B-57G specially designed for night interdiction missions in Vietnam.[1]
AN/APQ-146
editImproved AN/APQ-134 Ku band terrain-following radar by Texas Instruments for F-111C/F.[1]
AN/APQ-147
editTFR (Terrain-Following Radar) for initial batch of MH-60K[6]
AN/APQ-154
editImproved AN/APQ-141 terrain-following radar by Texas Instruments for HH-53.[1]
AN/APQ-158
editImprovement of AN/APQ-126 with 15 line replaceable units for the MH-53 Pave Low helicopter and PAVE LOW III requirement. Designed to perform terrain following mode/function in high clutter area such as in cities.[1]
AN/APQ-162
editDevelopment of AN/APQ-99 for RF-4C, incorporating experience gained from AN/APQ-116 and other radars in the family.[1]
AN/APQ-168
editMulti-mode radar by Texas Instruments for HH-60D & MH-60K. Increased jamming resistance, improved weather penetration, better guidance in turn flight, and better power management function in semi-covert mission. The radar can operate in terrain-clearance, terrain-avoidance, air-to-air ranging and cross-scan modes, the latter combining ground-mapping or terrain-avoidance with terrain-following. A terrain storage facility permits the radar to have a reduced duty cycle, thereby reducing the probability of detection by enemy ESM equipment. There's also the incorporation of built-in test (BITE) provides a high degree of fault isolation and detection.[1]
AN/APQ-171
editImproved AN/APG-146 terrain-following radar by Texas Instruments for F-111C/F, developed by Texas Instruments in the mid- eighties with the objective of replacing the four different TFR models used across the USAF F-111 fleet with a single type. While the old TFR had an MTBF around 20 hours, MBTF for the AN/APQ-171 is better than 50 hrs.[1]
AN/APQ-172
editImproved AN/APQ-162 TFR (Terrain-Following Radar) for RF-4C.[1]
AN/APQ-186
editAN/APN-237
editKu band terrain-following radar by Texas Instruments part of AN/AAQ-13[1]
References
edit- ^ a b c d e f g h i j k l m n o p q r "A History of Terrain-Following Radar by Tandy Penn, College of Engineering atTexas Tech University, Oct 15, 2005". Retrieved 2011-10-09.
- ^ a b "Terrain-following radar developed". Archived from the original on 2010-03-31. Retrieved 20 March 2013.
- ^ The Praetorian STARShip : the untold story of the Combat Talon. DIANE Publishing. 2001. p. 40. ISBN 978-1-4289-9043-2.
- ^ AN/APQ-126 photo
- ^ AN/APQ-126 performance
- ^ AN/APQ-147 on MH-60K
- ^ "AN/APQ-186". Archived from the original on 2008-09-07. Retrieved 2013-03-20.