The Mikoyan MiG-31, NATO reporting name "Foxhound", is a supersonic interceptor aircraft designed by the Mikoyan design bureau. A two-seater aircraft with the rear seat occupant controlling the radar, MiG-31 was the most advanced interceptor fielded by the Soviet Union before its dissolution. The MiG-31 was the world's first operational fighter with a passive electronically scanned array radar, the Zaslon S-800. Its maximum range against fighter-sized targets is approximately 200 km, and it can track up to 10 targets and simultaneously attack four of them with its AA-9 'Amos' missiles.

The MiG-31 with the Ye-155MP prototype first flew on September 16th 1975. Series production of the MiG-31 began in 1979, with operational models entering Soviet Anti-Air Defense (PVO) service in 1982. About 500 MiG-31s were produced, approximately 370 remain in Russian service, another 30 or so in Kazakhstan. A new version with upgraded avionics, MiG-31B, was introduced in 1990 as a result of the Soviet discovery that Phazotron radar division engineer Adolf Tolkachev had sold information on advanced radars to the West. Tolkachev was executed, and a new version of the compromised radar was hastily developed.