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Analytical and experimental research was conducted to investigate the use of a variable camber, cyclic controlled propeller, in combination with a partially-tilting wing with full-span flaps, to permit V/STOL aircraft operation. These features were incorporated in a full scale experimental aircraft designated the K-16B. This aircraft was used to explore the feasibility of a unified propulsion-control system designed to reconcile the conflict between the requirements of static thrust in hover and high-speed propeller efficiency, and to provide helicopter-type control in hover without the need for auxiliary control devices. This is accomplished by trailing edge flaps in the blades of the propeller. Collective deflection of these flaps increases blade camber for high static thrust. They are retracted in forward flight for a clean cruising-blade profile. Cyclic deflection of the flaps furnishes control moments in hover. The system was investigated on ground bench stands and in full-scale powered model tests of the K-16B.