Supercruise is sustained supersonic flight of a supersonic aircraft without using afterburner. Many supersonic military aircraft are not capable of supercruise and can maintain Mach 1+ flight only in short bursts with afterburners. Aircraft such as the SR-71 Blackbird are designed to cruise at supersonic speed with afterburners enabled.
Some fighter jets are capable of supercruise but only at high altitudes and in a clean configuration, so the term may imply "a significant increase in effective combat speed with a full weapons load over existing types".[1] One of the pre-eminent military examples of supercruise is the F-22 Raptor, for which supercruise was defined as "the ability to cruise at speeds of one and a half times the speed of sound or greater without the use of afterburner for extended periods in combat configuration."[2]
One of the best-known examples of an aircraft capable of supercruise, and the only notable non-military example, was the Concorde. Due to its long service as a commercial airliner, Concorde holds the record for the most time spent supersonic; more than all other western aircraft combined.[3]