Abstract: A high speed helicopter, ideally suited for use with rotors which are tip propelled, has an offset flapping hub mounted on a tiltable mast which is located a substantial distance off to the retreading blade side of the fuselage of the helicopter. This causes the fuselage to be located completely under the advancing blades. Individual pitch control motors individually vary the pitch of the rotor blades to control the feathering angle as a function of the angular position so that lift is obtained from the advancing and laterally moving blades only.

Abstract: A helicopter has a low profile electric motor mounted in each of the rotor blades to drive a cross-flow fan which draws air in through a slot at the leading edge of the blade and forces it out through an opposing slot adjacent the trailing edge of the blade to provide the thrust for rotating the rotor blade. An engine is located in the fuselage of the helicopter for driving an electric generator to produce the electricity supplied to the motors mounted in the blades. In addition, yaw control is achieved without the necessity of tail structure or a tail rotor using a small electric motor driving or absorbing power from the main rotor shaft. Both the yaw control motor and the main rotor shaft tilt together as a rigid unit. Pitch and roll control is achieved without the necessity of aerodynamic surfaces by movement of the main rotor support mast about a gimbal bearing support located above the center of gravity of the helicopter.