Windmill restart

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A windmill restart of a jet engine is a maneuver that uses the kinetic energy of the aircraft to attempt to restart an engine that has experienced a flameout. The procedure is designed to force air into the engine housing to spin the rotors and create enough pneumatic pressure for ignition. Typically in jet aircraft, to achieve the needed compression, airspeed of at least 300 knots is required, at which point the engine may be able to restart. However, due to the significant loss of altitude required for the procedure, it is generally deemed a last resort.