Abstract: A controllable kite, which changes its geometry and aerodynamic form in flight, in response to control inputs from control handles and control lines, enabling smooth stable high-speed flight as well as extreme low-speed agility and the ability to fly in any direction or hover, consists of a flexible leading-edge spar, stressed by the curve of the sail and providing tension in the sail. Control longerons, at a predetermined angle on either side of the centerline act on the leading-edge spar in such a way as to provide variable geometry that controls the form, stability and flying characteristics of the kite and sustains the shape required for both high and low-speed flight. Precise control is achieved by attaching equal-length control lines from control handles directly to the control longerons without the need for bridling.