In 1971, the USAF and U.S. Navy agreed to jointly develop the AIM-9L, a vastly improved Sidewinder based on the AIM-9H. Major development goals were ALASCA (All-Aspect Capability) and effective use against violently manoeuvering and high-speed targets at all ranges. The AIM-9L had new long-span pointed double-delta canards, a modified MK 36 solid-fuel rocket motor (MODs 8 through 11), and a new AN/DSQ-29 solid-state guidance and control section. Additional improvements include a completely new Argon-cooled Indium Antimonide (InSb) seeker, a DSU-15/B AOTD (Active Optical Target Detector) laser proximity fuze, and an improved 9.4 kg (20.8 lb) WDU-17/B annular blast-fragmentation warhead. All AIM-9L features resulted in a vastly improved missile which could acquire targets at all aspects, and had a much improved tracking, manoeuvering, terminal homing, and killing performance. Production started in 1978, and more than 16000 AIM-9Ls have been built by Philco-Ford, Raytheon, BGT (Germany), and Mitsubishi (Japan). The AIM-9L was used very successfully by the Royal Navy in the Falklands War during 1982.
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