F-22 SAR upgrade

Northrop Grumman, flying their BAC One Eleven testbed, has generated synthetic aperature radar maps using the F-22 active radar system. The call this Raptor Increment 3.1, and is a key upgrade for the aircraft. It converts the APG-77(V)1 into a dual mode target tracker. System level integration is set to begin mid year, with flight tests in 2009. Unless the USAF orders more aircraft, the line is set to close by the end of FY2009.

Northrop Grumman has generated synthetic aperture radar maps using the Lockheed Martin F-22A Raptor's active radar array, demonstrating a key component in the US Air Force's campaign to assert the future relevance of the imperilled stealth fighter.

Adding a SAR mode is part of the Raptor Increment 3.1 upgrade programme, which converts the F-22's air-to-air APG-77 radar into an dual-mode target tracker. Northrop confirms system level integration will start in mid-year, with a flight-test phase for the improvements in 2009.

The USAF added the air-to-ground radar mode in 2003, briefly renaming the Raptor the F/A-22. The "A" was dropped by incoming chief of staff Gen Michael Moseley in 2005.

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