 A rejected takeoff is normally performed only if the aircraft's speed is below the takeoff decision speed known as V1, which for larger multi-engine airplanes is calculated before each flight.Below the decision speed, the airplane should be able to stop safely before the end of the runway.Above the decision speed, the airplane may overshoot the runway if the takeoff is aborted, and, therefore, a rejected takeoff is normally not performed above this speed, unless there is reason to doubt the airplane's ability to fly.