AN/APG-65 radar family

The AN/APG 65 and AN/APG 73 are designations for a family of all weather multimode airborne radar systems designed by Hughes Aircraft (now Raytheon) for the F/A 18 Hornet, and used on a variety of fighter aircraft types. The APG 79 is an upgraded AESA version. These I band (8 to 12 GHz) pulse Doppler radar systems are designed for both air to air and air to surface missions. For air to air operations they incorporate a variety of search, track and track while scan modes to give the pilot a complete look down/shoot down capability. Air to surface modes include Doppler beam sharpened sector and patch mapping, medium range synthetic aperture radar, fixed and moving ground target track and sea surface search. In the F/A 18, the radar is installed in a slide out nose rack to facilitate maintenance.

The APG 65 was developed in the late 1970s and has been operational since 1983. The radar includes a velocity search (to provide maximum detection range capability against nose aspect targets), range while search (to detect all aspect targets), track while scan (which, when combined with an autonomous missile such as AIM 120, gives the aircraft a fire and forget capability), single target track, gun director and raid assessment (which enables the operator to expand the region centred on a single tracked target, permitting radar separation of closely spaced targets) operating modes. Although no longer in production, the APG 65 remains in service in F/A 18 Hornet strike fighters of the U. S. Navy and Marine Corps, and the air forces of Canada, Kuwait, and Spain. It has also been adapted to upgrade the German and Greek F 4 Phantom aircraft, and the AV 8B Harrier II Plus for the U. S. Marine Corps and the Spanish and Italian Navies.

The APG 73 is a late 1980s "upgrade of the APG 65 that provides higher throughputs, greater memory capacity, improved reliability, and easier maintenance". To reduce production costs, many of the upgraded radar's modules are common with the APG 70 (F 15E Strike Eagle) radar; its software engineers chose the JOVIAL programming language so that they could borrow and adapt existing software written for the APG 70. When fitted with a motion sensing subsystem and stretch waveform generator and special test equipment, the APG 73 can generate high resolution ground maps and make use of 'advanced' image correlation algorithms to enhance weapon designation accuracy. Since 1992 the APG 73 has been operational in U. S. Navy and Marine Corps F/A 18C and D aircraft; early models of the U. S. Navy F/A 18E/F Super Hornet; and in the air forces of Finland, Switzerland, Malaysia, Canada, and Australia. A total of 932 APG 73 systems were delivered, with the final delivery in 2006.