A system for altitude control of an autogyro includes an unpowered rotor for generating lift and a forward propulsion system for generating a horizontal thrust component of a thrust vector for propelling the autogyro forward during flight. The system for altitude control also includes at least one thrust steering control devices configured to steer thrust generated by the forward propulsion system such that the forward propulsion system generates a vertical thrust component of the thrust vector.

A helicopter rotor transmission in which the average lubricant monitoring and replenishment intervals are to be significantly increased. The helicopter rotor transmission has a central cavity, in which runs a bearing mast that is fixed in a locationally and rotationally manner, which is held passing through the gear housing at least partially in the direction of the central axis. An internally toothed gear ring of a rotatable rotor mast can be rotated about the central axis, with fixed rotation of the planetary gears about their planetary gear axes, such that the rotor mast can be set in rotation by means of a gear ring driver attached to the gear ring.

The invention relates to a drive system for a vehicle, comprising at least one asymmetrical rotor (18), which has at least one rotor blade (20) extending radially from a rotor axle, and a counterweight (22) which is opposite the rotor axle, the system further comprising a control device for the electric motor (24), which connects the electric motor (24) to a battery for the power supply thereof, and is configured and designed, during a revolution cycle, which includes 1-3 revolutions of the rigid rotor blade (20), to bring about at least one acceleration phase, in which the electric motor (24) can be accelerated to accelerate the rotor (18), and at least one braking phase, in which the electric motor (24) can be braked, the control device being designed, during at least part of the braking phase, to connect the electric motor (24) to at least one battery element (28) in generator mode.

A helicopter uses electric propeller torque arm as power source directly driving main rotor to rotate. The helicopter may be battery powered. The helicopter may be without an engine, a clutch, a reducer, a tail driver, a tail boom, a tail rotor and a fuel supply system. The main design goal is to have the output shaft of the high-energy motor being coaxial with the main rotor shaft or having output shafts of a plurality of motors as close as possible to the main rotor shaft. The centrifugal force of the motor(s) is negligible or minimized. The torque arm assembly includes a plurality of torque arms. Each of the torque arm of the plurality of torque arms includes a propeller and a driving system. In the case of a malfunction, the helicopter's main rotor will spin like a maple leaf and will facilitate the spin autorotation landing.

Aircraft capable of vertical takeoff and landing, hovering, and efficient forward flight are described. An aircraft includes two side mounted tiltable proprotors and a central rotor disposed above the proprotors. The proprotors are tiltable between at least a horizontal position for forward flight and a vertical position for vertical or hovering flight. The central rotor may be powered for vertical and transitional flight modes and may turn by free autorotation during forward flight. The proprotors may be differentially tilted during vertical or hovering flight to counter torque effects of the central rotor. The central rotor may be foldable and/or easily detachable from the aircraft to facilitate storage and transportation. Left and right proprotors may provide both forward thrust and attitude control. Control inputs to left and right proprotors may be connected directly to an autopilot creating closed loop actuation using motor RPM feedback.

A helicopter uses electric propeller torque arm as power source directly driving main rotor to rotate. The helicopter may be battery powered. The helicopter may be without an engine, a clutch, a reducer, a tail driver, a tail boom, a tail rotor and a fuel supply system. The main design goal is to have the output shaft of the high-energy motor being coaxial with the main rotor shaft or having output shafts of a plurality of motors as close as possible to the main rotor shaft. The centrifugal force of the motor(s) is negligible or minimized. The torque arm assembly includes a plurality of torque arms. Each of the torque arm of the plurality of torque arms includes a propeller and a driving system. In the case of a malfunction, the helicopter's main rotor will spin like a maple leaf and will facilitate the spin autorotation landing.

An embodiment includes a system for controlling blade pitch in a rotorcraft having an engine; a drive shaft with a first end and a second end and connected at the first end to the engine; a rotor with two or more blades connected to the second end of the drive shaft; and one or more actuators positioned adjacent to the rotor blades operable to change a blade pitch of the rotor blades.

Aircraft and methods of operating the aircraft to provide for increased descent angles. The aircraft includes a fuselage having fixed wings, a horizontal thrust source coupled to the fuselage and configured to selectively generate and supply horizontal thrust to the aircraft, a vertical thrust source coupled to the fuselage and configured to selectively generate and supply vertical thrust to the aircraft, the vertical thrust source including a vertical thrust rotor that is configured to selectively operate in a locked mode, in which the vertical thrust rotor cannot rotate freely in response to contact of airflow therewith, and an unlocked mode, in which the vertical thrust rotor can rotate freely in response to contact of airflow therewith, and a controller configured to selectively supply a command to the vertical thrust source that causes the vertical thrust rotor to operate in the unlocked mode.

A rotorcraft capable of a hover mode and a forward cruise mode including a fuselage, a first electric propulsion system, a second electric propulsion system, and an electric power control unit to control power to the first and second electric propulsion systems in the hover and forward cruise modes. The first electric propulsion system is a tip jet cold flow system that imparts rotation on a pair of rotor blades disposed above a top surface of the fuselage, and a first electric motor configured to drive the tip jet cold flow system. The second electric propulsion system includes a propeller disposed in the rear of the fuselage and a second electric motor configured to drive the propeller.

A multi-rotor aircraft includes a fuselage, a propulsion engine coupled to the fuselage that generates thrust to propel the aircraft along a first vector during forward flight, and rotors coupled to the fuselage, each rotor comprising blades, each rotor coupled to a motor, and each motor configured to supply power to and draw power from the coupled rotor. The aircraft includes a flight control system configured to control the motors coupled to the rotors in a power managed regime in which a net electrical power, consisting of a sum of the power being supplied to or drawn from each rotor by its motor, is maintained within a range determined by a feedback control system of the flight control system. The flight control system can also be leveraged to adjust rotor control inputs to modify at least one of thrust, roll, pitch, or yaw of the multi-rotor aircraft.