B64C2027/8227

Rotorcraft rotor and propeller speed

An aircraft includes an airframe having an extending tail, a counter rotating, coaxial main rotor assembly disposed at the airframe including an upper rotor assembly and a lower rotor assembly, and a translational thrust system positioned at the extending tail and providing translational thrust to the airframe, the translational thrust system including a propeller. A gearbox system is operably connected to the main rotor assembly and the propeller to drive rotation of the main rotor assembly and the propeller. The gearbox is configured to maintain a main rotor assembly tip speed below Mach 0.9 and a propeller helical tip speed below Mach 0.88.

Lift offset control of a rotary wing aircraft

An aircraft is provided including an airframe, an extending tail, and a counter rotating, coaxial main rotor assembly including an upper rotor assembly composed of a plurality of blades and a lower rotor assembly composed of a plurality of blades. A translational thrust system positioned at the extending tail, the translational thrust system providing translational thrust to the airframe. A flight control system to control the upper rotor assembly and the lower rotor assembly, wherein the flight control system is configured to control lift offset of the upper rotor assembly and the lower rotor assembly.

Quiet Redundant Rotorcraft

Provided is a quiet redundant urban rotorcraft, commonly known as urban air mobility eVTOL. The quiet redundant urban rotorcraft is designed to perform vertical takeoff and landings powered by two independent electric lifting motors. The lifting force is distributed among counter-rotating, co-axial main multi-bladed rotors and several smaller rotors distributed around the vehicle which provide attitude control during hover and low speed flight. The quiet redundant urban rotorcraft is capable to fly at relatively high horizontal speed by using a dedicated horizontal thrust propeller driven by an electric motor, turbine or internal combustion engine. In high speed flight, the main rotors turn freely, the control electric motors turn off and the attitude control is provided by aerodynamic fixed and moving surfaces. The quiet redundant urban rotorcraft has a low noise footprint and multiple redundancy for safety, while at the same time having a compact configuration for operating area restrictions.

PUSHER ROTORCRAFT DRIVETRAIN

A pusher rotorcraft is provided in one example embodiment and may include at least one engine in mechanical communication with a drop-down gearbox; a driveshaft in mechanical communication with the drop-down gearbox, a main rotor gearbox, and a tail system gearbox; a main rotor system in mechanical communication with the main rotor gearbox; an anti-torque system in mechanical communication with the tail system gearbox; and a pusher propeller system in mechanical communication with the tail system gearbox.

ROTORCRAFT ANTI-TORQUE SYSTEMS AND METHODS THEREFOR

A method of providing an anti-torque force in a rotorcraft with an anti-torque system comprised of a primary ducted tail rotor system mechanically connected to an engine, and a secondary ducted tail rotor system electrically connected to an electric power supply. The method includes receiving an indication of a change in the operating condition of the anti-torque system based upon a change in a rotorcraft condition input, a feedback input associated with a primary ducted tail rotor system and/or a secondary ducted tail rotor system, and/or a pilot input; responsive to the indication of the change, determining, by a control system, an anti-torque control input including at least a secondary output command for controlling the secondary ducted tail rotor system; and transmitting the secondary output command to the secondary ducted tail rotor system to energize at least one ducted tail rotor assembly therein to provide the second anti-torque force.

VERTICAL TAKE-OFF AND LANDING AIRCRAFT
20200023962 · 2020-01-23 · ·

An aircraft defining longitudinal, lateral and vertical directions the aircraft comprising:

a main wing and a tail, each being pivotable about the lateral direction;
a plurality of main propellers mounted to the main wing, and configured to pivot with the main wing;
at least one cruise propeller mounted to the tail, and configured to pivot with the tail;
the main propellers defining a swept disc area (A.sub.disc), and the main wing defines a wing area (Awing); wherein
a ratio of the disc swept area to the main wing area (A.sub.disc:A.sub.wing) is between 1 and 2.

VERTICAL TAKE-OFF AND LANDING AIRCRAFT

An aircraft defining longitudinal, lateral and vertical directions the aircraft comprising: a main wing and a tail, each being pivotable about the lateral direction (B); a plurality of main propellers mounted to the main wing, and configured to pivot with the main wing; at least one cruise propeller mounted to the tail, and configured to pivot with the tail; each main propeller being stowable from a deployed position to a stowed position; wherein each main propeller has a fixed pitch, and each cruise propeller has a variable pitch.

CANTED CO-AXIAL ROTORS FOR A ROTORCRAFT
20200017204 · 2020-01-16 ·

A rotorcraft has a frame and a plurality of rotors connected to the frame. The frame has a roll axis and a pitch axis. Each of the rotors includes a rotor shaft. The rotor shaft of each of the rotors is canted with respect to at least one of the roll axis and the pitch axis. The rotor shaft of each of the rotors may be canted between 3 and 15 degrees. Each of the rotors may be a co-axial co-rotating rotor. The rotors may be oriented in opposing pairs across the frame. Both rotors in each opposing pair rotate in the same direction. The rotorcraft may include at least two additional rotors, each having a forward cant. Each of the additional rotors may be a co-axial contra-rotating rotor.

Rotorcraft footprint
10527123 · 2020-01-07 · ·

An aircraft includes an airframe having an extending tail and a longitudinal axis extending from a nose of the airframe defining a length of the airframe. A counter rotating, coaxial main rotor assembly is located at the airframe and includes an upper rotor assembly and a lower rotor assembly. The upper rotor assembly and the lower rotor assembly rotate about an axis of rotation. The axis of rotation intersects the longitudinal axis forward of a midpoint of the longitudinal axis.

Electric distributed propulsion anti-torque redundant power and control system
10526085 · 2020-01-07 · ·

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.