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, and also tested on TA-3B. 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 computer with all-digital computer. 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 radar velocity search, range-while-search at shorter ranges, and the 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. AN/AWG-9 The AWG-9 was the result of a series of United States 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 ICBMs. The same was not true for the Navy, where the threat remained manned aircraft and early anti-ship missiles. Hughes suggested that the AN/ASG-18 and AIM-47 could be adapted for the Navy in slightly modified form, adding additional