The Mig-31 'Foxhound' was developed as the replacement of the Mig-25 'Foxbat', the prototype Ye-155MP took the first flight on 16 September 1975. As the heaviest fighter/interceptor in the world, the Mig-31 is much heavier than other similar aircraft. At the same time, two powerful D-30-F6 engines and a stronger airframe gave it a top speed to Mach 2.8 at high-altitude and Mach 1.23 at low-altitude.
The Mig-31 enter the operational service with the Soviet Air Defence Force in 1982, they were sent for a variety of long-range missions. More than 300 aircraft are in service in both Russian and Kazakhstan.