In 1979, the MiG-31 (Foxhound) stepped forward as a Foxbat replacement (although the Foxbat continued to operate into the Gulf War with the Iraq military) and offered some compelling enhancements ...

There have been rumors that during the late Cold War, a MiG-31 Foxhound may have been used to chase after the U.S. military's SR-71 Blackbird spy plane and reportedly locked on with its missiles ...