BALTIMORE, Sept. 8, 2005 -- Northrop Grumman Corporation (NYSE:NOC) has begun initial flight testing of the advanced fire-control radar being developed for the Lockheed Martin F-35 Joint Strike Fighter (JSF) aircraft. The radar is designed to enable F-35 pilots to effectively engage air and ground targets at long range, while also providing outstanding situational awareness for enhanced survivability.
Designated the AN/APG-81, the active electronically scanned array radar was first flown on Aug. 23 and 25 on Northrop Grumman's BAC-1-11 testbed aircraft. During the flights, the all-aspect search, air-track and synthetic-aperture radar mode capabilities of the radar were successfully evaluated against airborne and ground-based targets.
"The outstanding performance of the radar on these initial flights underscores the intense development effort under way on the F-35 mission avionics and marks the culmination of a successful design, hardware build, software development and systems integration process," said John C. Johnson, vice president of Combat Avionics Systems at Northrop Grumman. "We expect to accelerate the validation of the radar performance during the flight-test program and progress with the systems-integration effort ahead of schedule."
In addition to providing the radar, Northrop Grumman's Electronic Systems sector is providing the AN/AAS-37 electro-optical distributed aperture system for the F-35. The distributed aperture system will provide F-35 pilots with a unique protective sphere around the aircraft for missile warning, navigation support and night operations.
Grumman AN/APG-81 Active Electronically Scanned Array (AESA) radar, based on the AN/APG-77 AESA set developed for the Lockheed Martin F-22 Raptor. The AESA set consists of an array of Transmitter-Receiver (T/R) modules linked by high-speed processors. Different T/R modules in the array can be allocated to different tasks providing wide range of functions, thus acting as a multimode radar, active jamming system, passive electronic defense system, and communications system. The system generates signals over a wide range of frequencies and pulse patterns in an unpredictable fashion to ensure Low Probability of Intercept (LPI), successfully “fooling“ enemy Radar Warning Receivers (RWR).
The AN/APG-81 uses advanced technology compared to the F-22's AN/APG-77, but airframe constraints mean that it has fewer T/R modules, thus limiting its range to 165 km. The radar system will also incorporate the agile beam steering capabilities developed for the APG-77. Since US media reports indicate Bush administration’s clearance for possible transfer of sensitive radar technology like Raytheon AN/APG-79 AESA radar of the Super Hornet to India, diplomatic bargaining to secure the AN/APG-81 AESA radar may well bear fruit. Higher echelons of present US administration have repeatedly expressed their desire to witness the emergence of India into a robust continental military power.