AN/APG-77

The AN/APG-77 is a multifunction X-band, low probability of intercept radar installed aboard the F-22 Raptor fighter aircraft. The radar was designed and initially built by Westinghouse and Texas Instruments, and production continued with their respective successors Northrop Grumman and Raytheon after acquisition.
It is a solid-state, Active Electronically Scanned Array radar whose design is based on the AN/APG-66/68/80 family of fire control radars. Composed of 1,956 transmit/receive modules, each about the size of a gum stick, it can perform a near-instantaneous beam steering.
In accordance with the Joint Electronics Type Designation System, the "AN/APG-77" designation represents the 77th design of an Army-Navy airborne electronic device for radar fire-control equipment. The JETDS system is also now used to name all Department of Defense and some NATO electronic systems.

Implementation

The APG-77 was highly appreciated by pilots transitioning from F-15s upon the F-22's introduction in 2005, providing a massive boost in situational awareness. The APG-77 has an incredibly fast scan time across its 120 degree field of view and could detect aircraft from over away. The AN/APG-77 system itself exhibits a very low radar cross-section, supporting the F-22's stealthy design. The AN/APG-77 also features powerful jamming capabilities said to "fry" the electronics of enemy sensors.

Improvements

The upgraded version of the radar, designated APG-771, may have even greater range. Much of the technology developed for the APG-77 was used in developing the AN/APG-81 radar for the F-35 Lightning II, and in turn the technology from the APG-81 was applied upgrading to the APG-771. The APG-771 was installed aboard F-22 Raptors from Lot 5 onwards. The 1 improved air-to-air performance, full air-to-ground functionality, automatic cueing and recognition, combat identification, and many other advanced features.