X 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. AN/APQ-126 60 kW improved AN/APQ-116 J band terrain-following radar by Texas Instruments for A-7D/E AC-130 and CH-53 Sea Stallion. This is primarily AN/APQ-116/122 incorporating improved maritime capability. Specifications: 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 Ku band terrain-following radar by Texas Instruments to replace AN/APQ-110 for F-111A/FB-111A. AN/APQ-139 Ku band multi-mode radar by Texas Instruments for B-57G specially designed for night interdiction missions in Vietnam. AN/APQ-146 Improved AN/APQ-134 Ku band terrain-following radar by Texas Instruments for F-111C/F. AN/APQ-147 TFR for initial batch of MH-60K AN/APQ-154 Improved AN/APQ-141 terrain-following radar by Texas Instruments for HH-53. AN/APQ-158 Improvement 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. AN/APQ-162 Development of AN/APQ-99 for RF-4C, incorporating experience gained from AN/APQ-116 and other radars in the family. AN/APQ-168 multi-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. AN/APQ-171 Improved 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