UNDERSTANDING THE SHAPE-VARIABLE FOWLER FLAP

DaimlerChrysler Aerospace and the German Aerospace Center have begun studying the concept of a shape-variable fowler flap for an Airbus transport aircraft such as the A340.

The German Aerospace Center (DLR), DaimlerChrysler Research, and DaimlerChrysler Aerospace Airbus have partnered in the Adaptive Wing (ADIF) project, which was designed to show that high-lift behavior of modern transport aircraft can be improved with intelligent structural concepts without negative effects on cruise flight. From the project, engineers have shown that even an improvement in transonic flight is possible. To reach this aim, a combination of passive and active measures was employed.

Wings of modern transport aircraft are optimized for cruise flight. They have transonic wing profiles with the best lift/drag ratio at cruise speed. In the low-speed range, these profiles can be rather inefficient. Therefore, the required additional lift for takeoff and landing has to be achieved by using high-lift devices, such as slats at the wing leading edge and flaps at the trailing edge. In cruise configurations, slats and flaps are retracted.