A dual-motor system includes a first motor rotationally coupled to a first drive shaft. The first drive shaft is coupled to a common shaft couplable to a rotationally driveable member. The dual-motor system also includes a second motor rotationally coupled to a second drive shaft. The second drive shaft is coupled to the common shaft. The first motor and the second motor are coaxially aligned with the first drive shaft passing through the second drive shaft.

A yaw control system for a helicopter having a tailboom includes one or more tail rotors rotatably coupled to the tailboom and a quiet mode controller. The quiet mode controller includes a noise monitoring module configured to monitor one or more flight parameters of the helicopter and a quiet mode command module configured to selectively switch the one or more tail rotors to a quiet mode based on the one or more flight parameters. The quiet mode command module is also configured to modify one or more operating parameters of the one or more tail rotors in the quiet mode to reduce noise emitted by the helicopter.

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.

The present invention includes an electric distributed propulsion for anti-torque modules for a helicopter and methods of use comprising: two or more generators connected to a main gearbox transmission; at least a first and a second plurality of variable speed motors connected to one or more fixed pitch blades to provide anti-torque thrust connected to the two or more generators, and at least a first and a second yaw control computer independently connected to each of the at least first and second plurality of variable speed motors, wherein each of the first and second yaw control computer serves as a primary and a backup yaw control computer to provide redundant control to both the first and second plurality of variable speed motors.

The present invention includes an a plurality of first variable speed motors arranged in a first matrix pattern and 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.

Embodiments are directed to a flight control system for a helicopter comprises a pilot interface configured to receive a control input, at least one electronically controlled actuator, and a computing device configured to translate the control input to an actuator command, wherein the computing device is further configured to apply yaw rate limits to the actuator command to avoid loss of tail rotor effectiveness. The yaw rate limits are associated with a vortex ring state (VRS) envelope for a tail rotor of the helicopter. The electronically controlled actuator comprises a tail rotor actuator. The control input is a pedal input.

An architecture for an electric distributed propulsion system includes one or more generators connected to a gearbox, a first and a second plurality of motors connected to the one or more generators, each motor of the plurality of motors connected to a blade to provide thrust, a first and a second power bus electrically connected between the one or more generators and the first and the second plurality of motors, each power bus independent of the other power bus, a first and a second controller independently connected to each of the first and second plurality of motors, each of the first and second controllers serving as a primary and a backup controller to provide redundant control to both the first and the second plurality of motors, and dual channels in communication between pilot input sensors and the first and the second controllers, each channel of the dual channels independent of the other channels, and the dual channels including an additional channel to provide redundant communication to the first and second controllers.

A yaw control system for a helicopter having a tailboom and a forward flight mode includes a surface coupled to the tailboom, one or more tail rotors coupled to the surface, a flight control computer implementing a yaw controller having a rudder control module and a tail rotor rotational speed reduction module and a rudder rotatably coupled to the surface. The tail rotor rotational speed reduction module is configured to selectively switch the one or more tail rotors into a rotational speed reduction mode in the helicopter forward flight mode. The rudder control module is configured to rotate the rudder in the rotational speed reduction mode of the one or more tail rotors to control the yaw of the helicopter.

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.

A yaw control system for a helicopter having a tailboom includes one or more tail rotors rotatably coupled to the tailboom and a quiet mode controller. The quiet mode controller includes a noise monitoring module configured to monitor one or more flight parameters of the helicopter and a quiet mode command module configured to selectively switch the one or more tail rotors to a quiet mode based on the one or more flight parameters. The quiet mode command module is also configured to modify one or more operating parameters of the one or more tail rotors in the quiet mode to reduce noise emitted by the helicopter.