The AN/APG-73 is an I-band pulse-Doppler radar that was developed in the 1980s by Hughes Aircraft for the US Navy. It is used in the F/A-18 Hornet fighter aircraft. The AN/APG-73 features search, track and track-while-scan modes to give the pilot a complete look-down/shoot-down capability. It uses programmable digital processors to provide the features and flexibility needed for both air-to-air and air-to-surface missions. The APG-73 is a late 1980s upgrade of the APG-65 for higher processor throughput, greater memory capacity, bandwidth, frequency agility, higher analogue/digital sampling rates, improved reliability and easier maintenance. The 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 AN/APG-73 is installed in a slide-out nose rack to facilitate maintenance.
The AN/APG-73 is fitted with a motion-sensing subsystem and stretch waveform generator and special test equipment, being able to generate high resolution ground maps and make use of advanced image correlation algorithms to enhance weapon designation accuracy. The APG-73 has been operational in US Navy and Marine Corps F/A-18C, D, E, and F aircraft since 1992. Raytheon is the manufacturer of this radar, delivering units to the air forces of Finland, Switzerland, Malaysia, Canada, and Australia. A total of 932 APG-73 systems have been shipped, with the final delivery in 2006.