A tandem tiltrotor aircraft in which the tiltrotor assemblies are operably coupled at the forward and aft ends of the fuselage of the aircraft is disclosed. The tiltrotor assemblies are capable of rotating between a vertical lift position and a horizontal flight position. The in-line location of the tiltrotor assemblies allow the aircraft to have the vertical take-off and landing capabilities, and, in combination with the at least one wing, can be used in horizontal flight. The aft rotor assembly can assume a horizontal flight position that places the rotor blades forward of a vertical fin of the aircraft. In another embodiment, a winged triple tiltrotor aircraft is disclosed. In another embodiment, a winged quad tiltrotor aircraft is disclosed.

A tandem tiltrotor aircraft in which the tiltrotor assemblies are operably coupled at the forward and aft ends of the fuselage of the aircraft is disclosed. The tiltrotor assemblies are capable of rotating between a vertical lift position and a horizontal flight position. The in-line location of the tiltrotor assemblies allow the aircraft to have the vertical take-off and landing capabilities, and, in combination with the at least one wing, can be used in horizontal flight. The aft rotor assembly can assume a horizontal flight position that places the rotor blades forward of a vertical fin of the aircraft. In another embodiment, a winged triple tiltrotor aircraft is disclosed. In another embodiment, a winged quad tiltrotor aircraft is disclosed.

A coaxial rotor system for a rotorcraft includes a mast, a top rotor assembly and a bottom rotor assembly. The top rotor assembly is coupled to the distal end of the mast. The bottom rotor assembly includes a motor configured to provide rotational energy to the mast, thereby rotating the top rotor assembly. The bottom rotor assembly experiences a torque reaction force responsive to the motor rotating the mast such that the top and bottom rotor assemblies counter rotate.

A coaxial rotor system for a rotorcraft includes a mast, a top rotor assembly and a bottom rotor assembly. The top rotor assembly is coupled to the distal end of the mast. The bottom rotor assembly includes a motor configured to provide rotational energy to the mast, thereby rotating the top rotor assembly. The bottom rotor assembly experiences a torque reaction force responsive to the motor rotating the mast such that the top and bottom rotor assemblies counter rotate.

A method of controlling at least a first pitch of a first propeller and a second pitch of a second propeller of a hybrid helicopter, the hybrid helicopter having a thrust control and a yaw control that are configured to generate orders for modifying respectively a mean pitch component and a differential pitch component of the first pitch and of the second pitch, the hybrid helicopter having a collective pitch control for modifying a collective pitch component of main blades of the lift rotor. The method includes a step of: keeping with the control system the first pitch and the second pitch within a control domain that varies as a function of information relating to the collective pitch component.

A method of controlling at least a first pitch of a first propeller and a second pitch of a second propeller of a hybrid helicopter, the hybrid helicopter having a thrust control and a yaw control that are configured to generate orders for modifying respectively a mean pitch component and a differential pitch component of the first pitch and of the second pitch, the hybrid helicopter having a collective pitch control for modifying a collective pitch component of main blades of the lift rotor. The method includes a step of: keeping with the control system the first pitch and the second pitch within a control domain that varies as a function of information relating to the collective pitch component.

The application discloses a coaxial helicopter, the cyclic pitch-changing mechanism simultaneously adjusts the pitches of the upper and the lower rotor systems, to make uniformity cyclic pitch-changing adjustment of the upper and lower rotors, and make independent collective pitch adjustment of the upper rotor system; the differential pitch-changing mechanism and the cyclic pitch-changing mechanism jointly act on the lower rotor system, to perform differential collective pitch adjustment of the upper and lower rotor systems. The synchronous rotating mechanism drives the swashplate members to synchronously rotate along with the drive shaft. The application achieves a simpler hybrid pitch-changing control system of the coaxial rotor pitch, a plurality of flight operations of the coaxial aircraft are performed synchronously, and a plurality of flight control modes, such as semi-differential and full-differential in a variable speed or a fixed speed mode, are supported, and thus the present application has wider application space.

The application discloses a coaxial helicopter, the cyclic pitch-changing mechanism simultaneously adjusts the pitches of the upper and the lower rotor systems, to make uniformity cyclic pitch-changing adjustment of the upper and lower rotors, and make independent collective pitch adjustment of the upper rotor system; the differential pitch-changing mechanism and the cyclic pitch-changing mechanism jointly act on the lower rotor system, to perform differential collective pitch adjustment of the upper and lower rotor systems. The synchronous rotating mechanism drives the swashplate members to synchronously rotate along with the drive shaft. The application achieves a simpler hybrid pitch-changing control system of the coaxial rotor pitch, a plurality of flight operations of the coaxial aircraft are performed synchronously, and a plurality of flight control modes, such as semi-differential and full-differential in a variable speed or a fixed speed mode, are supported, and thus the present application has wider application space.

A rotor system for aerial vehicles where two or more rotor systems are used in a coaxial or tandem arrangement on the aerial vehicle.

A rotor system for aerial vehicles where two or more rotor systems are used in a coaxial or tandem arrangement on the aerial vehicle.