A new method for improving the aircraft landing performance

A new aerodynamic technique is presented. The main principle is to design a movable part on the upper surface of the wing. When the aircraft access to the relatively larger angle of attack in the period of landing, a step can be formed by appropriately raising the downstream tip of the movable part, thus a stable trapped vortex is generated to control the flow above the upper surface of the wing. At the same time, the Gurney flap which is installed at the trailing-edge of the wing is operated. Both effects of enlarging the lift and the stall angle of attack will be achieved. By the numerical simulation of DLR-F4, it is shown that the airfoil's maximum lift coefficient can be increased by 17.37%, and the stall angle of attack increases from 11 degree to 13 degree (increased by 18.18%). It is believed that the method presented to be a promising one for improving the aircraft landing performance for the small aircraft.