AWG-9

The AN/AWG-9 and AN/APG-71 radars are all-weather, multi-mode X band pulse-Doppler radar systems used in the F-14 Tomcat. It is a very long-range air-to-air system with the capability of guiding several AIM-54 Phoenix or AIM-120 AMRAAM missiles at the same time using its track while scan mode. The primary difference between the AWG-9 and APG-71 is the replacement of the former's analog electronics with all-digital units. Both the AWG-9 and APG-71 were designed and manufactured by Hughes Aircraft; contractor support is now being provided by Raytheon. The AWG-9 was originally developed for the failed Naval F-111B program.

The AN/AWG-9 offers a variety of air-to-air modes including long-range continuous wave velocity search, range-while-search at shorter ranges, and the first use of an airborne track-while-scan mode with the ability to track up to 24 airborne targets, display 18 of them on the cockpit displays, and launch against 6 of them at the same time. This function was originally designed to allow the Tomcat to shoot down formations of bombers at long range.

The AWG-9 was the result of a series of Navy programs to build what was known as a "fleet-defense fighter"; an aircraft armed with extremely long-range radars and missiles that would be able to engage formations of enemy aircraft well-away from aircraft carriers. Their first attempt was the F6D Missileer, which combined Westinghouse's AN/APQ-81 pulse doppler radar with the Bendix AAM-N-10 Eagle missile. The Missileer was a relatively simple aircraft, and when planners expressed doubts about its ability to survive after firing its missiles, the Missileer was canceled and the Navy started looking for higher-performance alternatives.

At the same time, the U.S Air Force had been working on a similar long-range interceptor project of their own, the XF-108 Rapier. The Rapier had much better performance than the Missileer, although its AIM-47 Falcon and AN/ASG-18 radar, both from Hughes, were somewhat less advanced than their Navy counterparts. The entire system was also very expensive, and the Rapier was canceled, replaced by the hopefully less-expensive Lockheed YF-12 adapted from the Lockheed A-12 spy plane. This project was also canceled as the strategic threat moved from bombers to ICBM's.

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Wikipedia