A cycloidal rotor is provided having a flexible by actuators or self-flexing blade-positioning tack, which can be brought into shape corresponding to currently desired blade orbit. This rotor can also be provided with frontal shielding or partial enclosure to assure that rotor operates at any speed as if in hovering flight; rotor track can be inclined to produce forward thrust or external thrusters can be used. Optionally in other embodiments blade orbit shape is determined by a variable cam mechanism or the inclination of blade positioning track of fixed shape to produce a change of its projected shape onto blades' plane of operation thus changing blades elliptic orbit. Blade centrifugal force countervailing mechanism is also proposed.

A pitch change link may include a shaft having a first end region and a second end region, and a bearing cartridge on at least one of the first end region and the second end region. The bearing cartridge may include a bearing and a bearing ring at least partially surrounding the bearing. The bearing ring may have a geometric symmetry and a cross section that is wider at a first end than at a second end, the first end may oppose the second end.

A pitch change link may include a shaft having a first end region and a second end region, and a bearing cartridge on at least one of the first end region and the second end region. The bearing cartridge may include a bearing and a bearing ring at least partially surrounding the bearing. The bearing ring may have a geometric symmetry and a cross section that is wider at a first end than at a second end, the first end may oppose the second end.

A flying device includes a base, thrusters, an orientation detection unit, an abnormality detection unit, and an orientation control unit. The plurality of thrusters are provided on the base each including a propeller, a motor which drives the propeller, and a pitch change mechanism unit which changes a pitch of the propeller. The orientation detection unit detects an orientation of the base. The abnormality detection unit detects an abnormality in the thrusters. The orientation control unit, when the abnormality detection unit detects an abnormality in at least one of the thrusters, changes the pitches of the propellers in the remaining thrusters to maintain an orientation of the base detected by the orientation detection unit.

A joint for an actuator of a rotorcraft includes a housing configured to be coupled to an input lever of the actuator; and a rotary bearing coupled to the housing, the rotary bearing comprising an inner race and an outer race and configured to be coupled to a control rod, wherein the inner race and outer race are rotationally fixed relative to each other until a torque applied to the joint exceeds a threshold torque value, upon which there is a relative rotatability between the inner race and the outer race.

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.

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.

An aircraft rotor system including a hub having a hub axis about which the hub is configured to rotate; a plurality of rotor blades configured to extend from the hub and rotate about the hub axis, at least one of the rotor blades rotatable about a respective pitch change axis; wherein the hub is configured to be rotated about the hub axis only by the plurality of rotor blades. Another aspect includes a method of operating the rotor system.

A vehicle includes a first rotor system having a rotor blade having an axis of rotation, a rotatable inboard drive component, and a rotatable outboard drive component. The first rotor system further includes a flexible closed loop component associated with each of the inboard drive component and the outboard drive component. Movement of the closed loop component can selectively cause at least one of rotation of the rotor blade about the axis of rotation and movement of the axis of rotation.

Tail rotor control system is described for helicopters. A pedal position sensor operable by a pilot yields greater tail rotor RPM relative to the main rotor RPM, giving the pilot increased control over the vehicle. This proves especially useful in certain situations, such as high altitude, where increasing tail rotor speed from main rotor speed can give a pilot increased maneuverability and stability.