The trailing edge of an aerodynamic surface such as a wing is its rear edge, where the airflow separated by the leading edge meets. Essential flight control surfaces are attached here to control the direction of the departing air flow, and exert a controlling force on the aircraft. Such control surfaces include ailerons on the wings for roll control, elevators on the tailplane controlling pitch, and the rudder on the fin controlling yaw. Elevators and ailerons may be combined as elevons on tailless aircraft.
The shape of the trailing edge is of prime importance in the aerodynamic function of any aerodynamic surface. George Batchelor has written about:
Other sharp-edged surfaces that are attached to the trailing edges of wings or control surfaces include:
Other equipment that may be attached to the trailing edges of wings include:
The trailing edge may either have a triangle-like or cusp-like shape. A trailing edge with a triangle-like shape is also often referred to as a trailing edge that has a finite angle.