The Sukhoi Su-15 (NATO reporting name 'Flagon') was a twin-engined supersonic interceptor developed by the Soviet Union. It entered service in 1965 and remained one of front-line designs into the 1990s. The Su-15 was designed to replace the Sukhoi Su-11 and Sukhoi Su-9, which were becoming obsolete as NATO introduced newer and more capable strategic bombers.
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