Sukhoi su-15 is a dual engine jet fighter developed by the Soviet Union in the 1960s to replace the SU-11 fighter. The su-15 has some shortcomings in the operational radius, but it has been proved to be extremely excellent in other aspects. According to the order issued by the Soviet government on April 3, 1965, it began to be developed. In 1966, it began mass production. In 1967, it was equipped with the Soviet air defense force to replace the su-9, SU-11 and jacques-25 fighters. The su-15 fighter was a forward deployed fighter until the 1990s. The original su-15 was referred to by NATO as "pinhead-a". The su-15ut (NATO code name "pinhead-c"), a trainer without radar or weapons, also began service in 1970. After the end of the cold war, the soviet-15 retired from the Russian air defense force in 1993.