Systems and methods include providing a helicopter, with a fuselage, a tail boom extending from the fuselage, a main rotor system, and a tail rotor assembly disposed on an aft end of the tail boom. The tail rotor assembly includes a tail rotor housing, at least one normal ducted fan that generate anti-torque thrust to prevent rotation of the fuselage, and at least one canted ducted fan configured to generate both anti-torque thrust to prevent of the fuselage and lift to the tail boom in order to control the pitch of the helicopter. The canted ducted fans generate sufficient lift to prevent a nose-up orientation of the helicopter when the center of gravity of the helicopter is shifted rearward behind the main rotor system, while the normal ducted fans maintain sufficient anti-torque thrust to prevent rotation of the fuselage when the main rotor is operated.

In an air mobility vehicle, an engine operates as required to provide mechanical driving force or electric energy. A battery is charged with the electric energy from the engine. Main rotors operate using the electric energy of the battery and electric power generated by the engine to perform takeoff, landing, and cruising. Auxiliary rotors are disposed at or adjacent to the center of gravity of a vehicle body and mechanically connected to the engine via a clutch. The auxiliary rotors perform the takeoff, the landing, or the cruising by receiving the mechanical driving force from the engine when the clutch is in an engaged position. A controller monitors the states of the battery and the main rotors and controls the operations of the engine and the clutch.

A system and method for slowing the rotation of a rotor using, for example, rotor brake system for a rotorcraft comprises: one or more generators connected to a main rotor gearbox; an electric distributed anti-torque system mounted on a tail boom of the rotorcraft comprising two or more electric motors connected to the one or more generators, wherein the two or more electric motors are connected to one or more blades; and wherein a rotation of the rotor is slowed by placing a drive load on the main rotor gearbox with the one or more generators to bleed the mechanical power from rotor into electrical power via the two or more electric motors, wherein the electric distributed anti-torque system generates thrust in opposing directions.

In an air mobility vehicle, an engine operates as required to provide mechanical driving force or electric energy. A battery is charged with the electric energy from the engine. Main rotors operate using the electric energy of the battery and electric power generated by the engine to perform takeoff, landing, and cruising. Auxiliary rotors are disposed at or adjacent to the center of gravity of a vehicle body and mechanically connected to the engine via a clutch. The auxiliary rotors perform the takeoff, the landing, or the cruising by receiving the mechanical driving force from the engine when the clutch is in an engaged position. A controller monitors the states of the battery and the main rotors and controls the operations of the engine and the clutch.

Systems and methods include providing an aircraft with a fuselage, a tail boom or empennage extending from the fuselage, a main rotor, a tail rotor, and at least one counter torque device. The counter torque device provides counter torque to the fuselage to prevent rotation of fuselage when the main rotor is operated, particularly in right sideward flight (RSF) for conventional helicopters with a counter-clockwise rotating (when viewed from above the helicopter) main rotor.

The present invention includes a rotor hub system, comprising: a teetering rotor hub disposed about a mast, the teetering rotor hub comprising: a first and a second yoke; each connected to a set of rotor blades, wherein the second set of rotor blades and the first set of rotor blades are disposed in a common plane, but the first and the second yoke do not come in contact.

In one aspect, there is provided an aircraft, including a fuselage having a longitudinal axis extending from a front portion through an aft portion; first and second tail members extending from the aft portion; a first cross-flow fan system rotatably mounted to the first tail member; and a second cross-flow fan system rotatably mounted to the second tail member. The first and second cross-flow fan systems are configured to provide a forward thrust vector and an anti-torque vector on the aircraft. The first and second cross-flow fan systems can have a rotational axis oriented generally vertically. In another aspect, there is an aircraft including a fuselage having a front portion and a tail portion; and a cross-flow fan system supported by the tail portion. Embodiments include a cross-flow fan system retrofittable onto an aircraft and methods for retrofitting an aircraft with a cross-flow fan system.

A control circuitry includes a first filter configured to generate a filtered velocity based on a component of a vertical velocity of an aircraft. The pitch trim prediction circuitry also includes a second filter configured to generate a filtered pitch attitude based on a measured pitch attitude of the aircraft. The pitch trim prediction circuitry further includes output circuitry configured to generate a predicted pitch attitude trim value for a target vertical state based on a horizontal velocity of the aircraft, the filtered velocity, and the filtered pitch attitude. The predicted pitch attitude trim value is configured to cause a flight control effector to be adjusted.

A control circuitry includes a propulsor trim prediction circuitry configured to generate a predicted propulsor collective blade pitch trim value for a target state of an aircraft based on an aircraft velocity and a pitch attitude deviation from a reference. The control circuitry further includes an output circuitry configured to output a propulsor collective blade pitch angle command based on the predicted propulsor collective blade pitch trim value. The propulsor collective blade pitch angle command is configured to cause an adjustment in a blade pitch angle of a propulsor of the aircraft. Additionally or alternatively, the control circuitry includes a pitch attitude trim prediction circuitry configured to generate a predicted pitch attitude trim value. The output circuitry is configured to output an aircraft pitch attitude trim command, configured to cause an adjustment in a pitch angle of the aircraft, based on the predicted pitch attitude trim value.

A control circuitry includes a propulsor trim prediction circuitry and an output circuitry. The propulsor trim prediction circuitry is configured to generate a predicted proprotor nacelle trim value based on an aircraft velocity and a pitch attitude deviation from a reference. The output circuitry is configured to output a proprotor nacelle command based on the predicted proprotor nacelle trim value. The proprotor nacelle command is configured to cause an adjustment in a nacelle angle of a proprotor of an aircraft.