The Mikoyan MiG-31 (Russian: МиГ-31) (NATO reporting name: Foxhound) is a supersonic interceptor aircraft developed to replace the MiG-25 ‘Foxbat’. The MiG-31 was designed by the Mikoyan design bureau based on the MiG-25. The MiG-31 was the most recent interceptor fielded by the Soviet Union before its dissolution. en.wikipedia.org/wiki/Mig_31