Mikoyan-Gurevich MiG-25 (West called in Foxbat) was an aircraft that could fly with a speed greater than Mach 3 and was developed during the '60s. Its purpose was to cover the needs of the Soviet Union for a reconnaissance aircraft that could fly at high speeds and altitudes. It made its first flight in 1967. Its introduction caused several concerns to the US, which almost instantly started developing the F-15 air superiority fighter to counter the Soviet threat. The production of the MiG-25P (interceptor) started in 1971 and started serving in 1972. The aircraft was being produced at the same time in different versions. Almost 1,186 MiG-25s were built until 1985 when the production stopped forever. The aircraft was exported to other countries. From the first time of its entrance, MiG-25 was a critical weapon for the Soviet Air Force and its air defense capabilities. After the Delusion of the Soviet Union, the aircraft was split into new countries. During the '90s, MiG-25 was still very important for Russia, but the numbers were fewer as time was passing. The aircraft performed operations during 1999 Chechnya and in 2001, Russia still operated some MiG-25PD/PDS interceptor aircraft. In 2010 42 MiG-25RB (interceptor/bombing version) stayed in serving. MiG-25 was permanently retired from the Russian air force, but some countries like Algeria and Syria probably still have active MiG-25s in their armory.
The interceptor aircraft was designed to compete with aircraft of high speeds and altitudes, like the legendary SR-71 Blackbird. MiG-25 had an impressive performance and achieved fast speeds, high altitudes, and a great rate of climb. However, nothing is perfect: maneuverability and low-speed flights were two of its worse characteristics.
MiG-25PD entered service in 1978 and was the ultimate Foxbat aircraft with an RP-25 radar, infrared tracking and targeting system, R-15BD-300 engines, and extra fuel tanks with huge capacity.
MiG-25RB was an aircraft capable of performing reconnaissance and bombing missions. The aircraft could carry 500kg of bombs and release them at an altitude greater than 20,000 meters while flying at hypersonic speeds. Some versions of MiG-25RB featured special systems for special missions. The MiG-25U was the trainer version of the reconnaissance MiG-25.
MiG-25BM was a single-seat defense suppression version that carried the Kh-31 and Kh-587 missiles.
MiG-31 was the successor of MiG-25, an aircraft that was introduced in 1982 and till today, it's the basic aircraft of the Russian air defense forces. MiG-31 never achieved the production numbers of the MiG-25.