Abstract: An ultralight coaxial dual rotor helicopter having a substantially L shaped frame. Attached to the back of the frame is a vertical shaft engine, and a pair of yaw paddles for controlling yaw of the craft. The drive shaft connects to a belt drive at the top of the frame, which transmits the engine power to a transmission and coaxial drive gear for driving the rotors. Crank actuators are provided for tilting the rotor axis to control the pitch and roll of the craft. A pilot seat and ballast tank are attached to the front of the frame. The ballast tank may be filled with a volume of water to balance the craft for the weight of the pilot. The fuel tank is located behind the pilot seat on the centerline of the helicopter, such that as fuel is used and the weight of fuel in the tank changes, the balance of the craft will not be affected.

Abstract: An ultralight coaxial dual rotor helicopter having a substantially L shaped frame. Attached to the back of the frame is a vertical shaft engine, and a pair of yaw paddles for controlling yaw of the craft. The drive shaft connects to a belt drive at the top of the frame, which transmits the engine power to a transmission and coaxial drive gear for driving the rotors. Crank actuators are provided for tilting the rotor axis to control the pitch and roll of the craft. A pilot seat and ballast tank are attached to the front of the frame. The ballast tank may be filled with a volume of water to balance the craft for the weight of the pilot. The fuel tank is located behind the pilot seat on the centerline of the helicopter, such that as fuel is used and the weight of fuel in the tank changes, the balance of the craft will not be affected.

Abstract: A coaxial helicopter, comprising a first rotor carried by a first shaft and a second rotor carried by a second shaft; wherein one of the first and second rotors has cyclic pitch control and the other rotor does not have cyclic pitch control, at least pitch and roll control being implemented by cyclic blade pitch control of only one rotor of the coaxial rotor set. Provisions for yaw control can include differential collective control of the first and second rotors, providing yaw paddles and/or a tail rotor, ducted fan, or an air jet configured for yawing the coaxial helicopter.

Abstract: An ultralight coaxial dual rotor helicopter having a substantially L shaped frame. Attached to the back of the frame is a vertical shaft engine, and a pair of yaw paddles for controlling yaw of the craft. The drive shaft connects to a belt drive at the top of the frame, which transmits the engine power to a transmission and coaxial drive gear for driving the rotors. Crank actuators are provided for tilting the rotor axis to control the pitch and roll of the craft. A pilot seat and ballast tank are attached to the front of the frame. The ballast tank may be filled with a volume of water to balance the craft for the weight of the pilot. The fuel tank is located behind the pilot seat on the centerline of the helicopter, such that as fuel is used and the w eight of fuel in the tank changes, the balance of the craft will not be affected. A simplified electronic control system controls all functions of the helicopter in response to pilot input.

Abstract: A helicopter propulsion and control system configured for actuating a helicopter airframe according to control inputs of an operator, comprising a counter-rotating rotor set tiltably coupled to the airframe at a first location, the rotor set having a downward thrust vector and a power assembly configured to actuate the counter-rotating rotor set, having a center of gravity, and being fixedly coupled to the rotor set so as to be tiltable therewith, the center of gravity of said power assembly being disposed below the first location where the rotor set is tiltably coupled to the airframe and a control actuator operatively coupled between the power assembly and the airframe to enable the center of gravity of the airframe to move with respect to the center of gravity of the power assembly, and with respect to the thrust vector of the rotor set, whereby pitch and roll of the airframe are controllable by the operator.

Abstract: A coaxial helicopter, comprising a first rotor carried by a first shaft and a second rotor carried by a second shaft; wherein one of the first and second rotors has cyclic pitch control and the other rotor does not have cyclic pitch control, at least pitch and roll control being implemented by cyclic blade pitch control of only one rotor of the coaxial rotor set. Provisions for yaw control can include differential collective control of the first and second rotors, providing yaw paddles and/or a tail rotor, ducted fan, or an air jet configured for yawing the coaxial helicopter.