AWG-9 and APG-71 radars

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Tactical information display (TID) of radar data in the rear seat of an F-14A.

The AN/AWG-9 and AN/APG-71 radars are all-weather multimode radar systems designed by Hughes Aircraft (now Raytheon) for the U.S. Navy's F-14 Tomcat fleet defense fighter.

These X-Band pulse-doppler radar systems are designed to detect and track up to 24 airborne targets at long ranges, selectively attacking up to 6 of those targets simultaneously. The radars are optimized to work in tandem with the AIM-54 Phoenix missile, which was carried exclusively on the F-14. Both the AWG-9 and APG-71 were designed and manufactured by Hughes Aircraft; contractor support is now being provided by Raytheon.

[edit] AN/AWG-9

The AWG-9 was originally developed in the late 1960s for use on the F-111B, but transitioned to the F-14A when the F-111B program was canceled. The system incorporated the highest-power transmitter ever installed in a production fighter aircraft, and as a result was capable of detecting bomber-sized targets at ranges exceeding 100 miles (160 km). The AWG-9's advanced analog signal processor analyzes the doppler effect of returned pulses to determine the velocity of the object. This allows it to pick out moving objects from stationary ground or sea clutter, aiding in detecting and tracking small low-flying targets.^[1]

Hughes delivered enough AWG-9 systems and spares to equip approximately 600 F-14A/B aircraft for the U.S. Navy, and an additional 80 aircraft for the Iranian Air Force. All of the U.S. Navy systems have been retired; the status of the Iranian systems is unknown, but it is believed that a few may still be in service.

[edit] AN/APG-71

The APG-71 was a 1980s upgrade of the AWG-9 for use on the F-14D. It incorporates technology and common modules developed for the APG-70 used in the F-15E Strike Eagle, providing significant improvements in (digital) processing speed, mode flexibility, clutter rejection, and detection range. The system features a low-sidelobe antenna, a sidelobe-blanking guard channel, and monopulse angle tracking, all of which are intended to make the radar less vulnerable to jamming.

The system itself is capable of a 460 mile (740 km) range, but the antenna design limits this to only 230 miles (370 km). Use of datalinked data allows two or more F-14D's to operate the system at its maximum range.

Hughes delivered enough APG-71 radars and spares to equip 55 F-14Ds before the program was scaled back as a cost-cutting measure and eventually canceled. These systems will remain in service until the last squadron (VF-31) is retired, expected in September 2006.