The Mikoyan-Gurevich MiG-25 (; NATO reporting name: Foxbat) is a supersonic interceptor and reconnaissance aircraft that is among the fastest military aircraft to enter service. Designed by the Soviet Union's Mikoyan-Gurevich bureau, it is an aircraft built primarily using stainless steel. It was to be the last plane designed by Mikhail Gurevich, before his retirement. The first prototype flew in 1964 and the aircraft entered service in 1970. It has an operational top speed of Mach 2.83. Although its thrust was sufficient to reach Mach 3.2+, its speed was limited to prevent engines from overheating at higher air speeds and possibly damaging them beyond repair. The MiG-25 features a powerful radar and four air-to-air missiles and was theoretically capable of a ceiling of . When first seen in reconnaissance photography, the large wings suggested an enormous and highly maneuverable fighter, at a time when U.S. design theories were also evolving towards higher maneuverability due to combat performance in the Vietnam War. The appearance of the MiG-25 sparked serious concern in the West and prompted dramatic increases in performance for the McDonnell Douglas F-15 Eagle, then under development in the late 1960s. The capabilities of the MiG-25 were better understood by the West in 1976 when Soviet pilot Viktor Belenko defected in a MiG-25 to the United States via Japan. It turned out that the aircraft's weight necessitated its large wings. Production of the MiG-25 series ended in 1984 after completion of 1,186 aircraft. A symbol of the Cold War, the MiG-25 flew with Soviet allies and former Soviet republics, remaining in limited service in several export customers. It is one of the highest-flying military aircraft, one of the fastest serially produced interceptor aircraft, and the second-fastest serially produced aircraft after the SR-71 reconnaissance aircraft, which was built in very small series compared to the MiG-25. , the MiG-25 remains the fastest manned serially produced aircraft in operational use and the fastest plane that was offered for supersonic flights and edge-of-space flights to civilian customers. Design and development Background During the Cold War, Soviet Air Defence Forces, PVO (not to be confused with Soviet Air Force, VVS) was given the task of strategic air defence of the USSR. This meant not only dealing with accidental border violations, but more importantly defending the vast airspace of the USSR against US reconnaissance aircraft and strategic bombers carrying free-fall nuclear bombs. The performance of