 Krüger flaps were invented by Werner Krüger in 1943 and evaluated in the wind tunnels in Göttingen, Germany.One of the earliest civil applications was the Boeing 707 whereas swiss FFA claimed the first use of the flap in its FFA P-16 fighter which flew in 1955.The flap was added to prevent wing stall with an extreme attitude take-off with the tail dragging on the runway, a scenario that had already caused two de Havilland Comet accidents.