Definition
A type of leading-edge high-lift device that hinges down and forward from the underside of the wing's leading edge to increase wing camber and lift at low airspeeds, typically used during takeoff and landing on jet transport aircraft.
Plain English
A panel on the front edge of the wing that swings down and forward to give the wing more lift when the airplane is flying slowly, such as during takeoff and landing.
Context Anchor
Seen in airfoil design and high-lift device discussions, especially when comparing different ways a wing can increase lift at low speed.
Derivation
Named after Werner Kruger, a German aerodynamicist who developed the concept in the 1940s at the Aerodynamische Versuchsanstalt in Göttingen. The spelling 'Kreuger' is a common variant of the original name 'Krueger.' Knowing it is a person's name explains why it isn't descriptive like 'slat' or 'flap'.
Why Pilots Care
They improve an airplane's ability to take off and land at slower speeds, reducing runway length requirements.
Intuition Check
Do not picture a normal rear-edge flap. Kreuger flaps are on the front edge of the wing and fold out from underneath.
Example Sentence 1
As the crew selected flaps for takeoff, the Kreuger flaps extended from the inboard leading edge of each wing.
Example Sentence 2
Kreuger flaps are particularly useful on jet transports for increasing wing camber during approach.