Abstract: The aircraft incorporates a primary and two control ducted propeller assemblies. The propellers are interconnected for rotation by a single engine. Each propeller assembly is inclined in horizontal flight and has two groups of louvers. When the groups of louvers in a propeller assembly are set to divert air horizontally in opposed directions, reduced vertical thrust is realized. In this manner, pitch and roll may be controlled in vertical flight. Vanes on the control ducts produce differential horizontal thrust to control yaw in the vertical mode. In horizontal flight, all groups of louvers are set to direct the flow aft to produce thrust for high speed forward flight.