An anti-torque system (10) for a helicopter (1) is described that comprises: an electric power supply unit (15); at least one first rotor (17), operatively connected to an electric power supply unit (15) and operable by the electric power supply unit (15) so as to rotate with a first variable angular speed; and at least one second rotor (25) operatively connected to electric power supply unit (15) and operable by the electric power supply unit (15) so as to rotate with a second variable angular speed.

An exemplary tail rotor includes a first blade assembly configured to rotate in a first direction about an axis of rotation and a second blade assembly configured to rotate in a second direction about the axis of rotation.

An exemplary dual motor input includes a common shaft for coupling to a member to be rotationally driven, a first motor rotationally coupled to a first drive shaft, the first drive shaft coupled to the common shaft, and a second motor rotationally coupled to a second drive shaft, the second drive shaft coupled to the common shaft.

An electrically distributed yaw control system for a helicopter having a tailboom and a power system includes one or more tail rotors including a motor rotatably coupled to the tailboom and a power distribution unit. The power distribution unit includes a power management monitoring module configured to monitor one or more flight parameters of the helicopter and a power management command module configured to allocate power between the power system and the one or more tail rotor motors based on the one or more flight parameters of the helicopter.

According to one implementation of the present disclosure, a tail rotor system of a rotorcraft includes an electric motor, a swiveling actuator, a spindle, and a hub assembly. The hub assembly may be configured to position two or more blades. Also, in response to a control signal, the swiveling actuator may be configured to actuate swivel rotation of the spindle around a vertical axis such that the hub assembly turns from a first horizontal directional axis to a second horizontal directional axis.

An anti-torque system for a rotorcraft includes a first tail fan assembly including a plurality of first fan blades, a second tail fan assembly including a plurality of second fan blades and a motor adapted to provide torque to the first and second fan blades. The first fan blades have a larger rotational inertia than the second fan blades. The second fan blades are adapted to experience a larger angular acceleration than the first fan blades in response to torque from the motor, thereby providing responsive yaw control for the rotorcraft.

An exemplary rotorcraft includes a propulsion system including a prime mover and a drive shaft coupled to the prime mover, the drive shaft including a coupling separating the drive shaft into an input shaft and an output shaft, the coupling operable between an engaged position rotationally coupling the input shaft and the output shaft and a disengaged position rotationally disengaging the output shaft from the input shaft, a main rotor coupled to the prime mover, a secondary rotor attached to the output shaft, and a motor coupled to the output shaft.

The present invention includes an a plurality of first variable speed motors mounted on a tail boom of the helicopter; one or more fixed pitch blades attached to each of the plurality of first variable speed motors; and wherein a speed of one or more of the plurality of first variable speed motors is varied to provide an anti-torque thrust.

A fully compounding rotorcraft includes a fuselage having first and second wings extending therefrom and configured to provide lift compounding responsive to forward airspeed. A twin boom includes first and second tail boom members that extend aftward from the first and second wings. An empennage is coupled between the aft ends of the tail boom members. An anti-torque system includes a tail rotor that is rotatably coupled to the empennage. An engine is disposed within the fuselage and is configured to provide torque to a main rotor assembly via an output shaft and a main rotor gearbox. An auxiliary propulsive system is coupled to the fuselage and is configured to generate a propulsive thrust to offload at least a portion of a thrust requirement from the main rotor during forward flight, thereby providing propulsion compounding to increase the forward airspeed of the rotorcraft.

The present invention includes an anti-torque assembly for a helicopter comprising a plurality of fixed blade pitch motors mounted on one or more pivots on the tail boom of the helicopter, wherein the plurality of fixed blade pitch motors on the one or more pivots are adapted to be oriented substantially in-plane with a tail boom of a helicopter during a first mode of operation that comprises a hover mode and wherein the fixed blade pitch motors are adapted to be oriented substantially off-plane from the tail boom of the helicopter during a second mode of helicopter operation that is different from the first mode.