An unmanned rotorcraft includes an airframe, rotor blades that are coupled to the airframe for rotation therewith, a propulsion unit having a propeller, and an actuator that is coupled to the airframe and adapted to temporarily reorient the propulsion unit such that an axis of the propeller moves out of alignment with an axis of the rotor blades. Rotation of the propeller causes counter-rotation of the airframe and rotor blades. The rotor blades and blades of the propeller are adapted to deploy from collapsed positions when flight of the rotorcraft is initiated. A method of operation by the rotorcraft includes, when it is determined that a current heading does not correspond to a determined flight path, causing the actuator to temporarily reorient the propulsion unit in accordance with an angular orientation of the actuator relative to the current heading.

A stowable lift rotor is coupled to an airframe of a VTOL aircraft. The VTOL aircraft is convertible between a VTOL flight mode and a forward flight mode. The stowable lift rotor includes a lift arm. The proximal end of the lift arm is coupled to the airframe of the VTOL aircraft. The stowable lift rotor also includes a rotor assembly including rotor blades coupled to the distal end of the lift arm. The lift arm is movable between various positions including an extended position in the VTOL flight mode, a stowed position in the forward flight mode and intermediate positions therebetween such that the distance between the rotor assembly and the airframe is greater in the extended position than in the stowed position.

An exemplary clamp system for securing a proprotor blade in a stowed position includes a clamp having a pair of opposing pads operable between an open position to receive a portion of a proprotor blade between the pair of opposing pads and a closed position to grip the portion of the proprotor blade with the pair of opposing pads and a rotary actuator in connection with the clamp to operate the clamp between the open and the closed position.

An exemplary clamp system for securing a proprotor blade in a stowed position includes a clamp having a pair of opposing pads operable between an open position to receive a portion of a proprotor blade between the pair of opposing pads and a closed position to grip the portion of the proprotor blade with the pair of opposing pads and a rotary actuator in connection with the clamp to operate the clamp between the open and the closed position.

A foldable propeller assembly for an aerial vehicle is disclosed herein. The foldable propeller assembly comprises a propeller blade arranged pivotably about a pivot axis and a first hub element arranged stationary relative to the pivot axis. The propeller blade or the first hub element comprises at least two openings provided about the pivot axis, each opening is configured for interlocking with a raised portion provided on the other one of the propeller blade and the first hub element. The at least two openings extend further about the pivot axis than the raised portion such that the propeller blade has limited play about the pivot axis when an opening is interlocking with the raised portion. A biasing element is arranged about the pivot axis and configured for biasing the propeller blade and the first hub element towards each other in an axial direction along the pivot axis.

An aircraft having a high efficiency forward flight mode. The aircraft includes an airframe having at least one wing. A distributed propulsion system is attached to the airframe and includes a first plurality of propulsion assemblies and a second plurality of propulsion assemblies. A flight control system is operably associated with the distributed propulsion system and is operable to independently control each of the propulsion assemblies. The aircraft is configured for thrust-borne lift in a vertical takeoff and landing flight mode and wing-borne lift in the forward flight mode. In the vertical takeoff and landing flight mode, each of the propulsion assemblies is configured to generate vertical thrust. In the forward flight mode, the propulsion assemblies of the first plurality of propulsion assemblies are configured to generate forward thrust and the propulsion assemblies of the second plurality of propulsion assemblies are configured to shut down.

An aircraft having a high efficiency forward flight mode. The aircraft includes an airframe having at least one wing. A distributed propulsion system is attached to the airframe and includes a first plurality of propulsion assemblies and a second plurality of propulsion assemblies. A flight control system is operably associated with the distributed propulsion system and is operable to independently control each of the propulsion assemblies. The aircraft is configured for thrust-borne lift in a vertical takeoff and landing flight mode and wing-borne lift in the forward flight mode. In the vertical takeoff and landing flight mode, each of the propulsion assemblies is configured to generate vertical thrust. In the forward flight mode, the propulsion assemblies of the first plurality of propulsion assemblies are configured to generate forward thrust and the propulsion assemblies of the second plurality of propulsion assemblies are configured to shut down.

The present invention includes a distributed propulsion system for a craft that comprises a frame, a plurality of hydraulic or electric motors disposed within or attached to the frame in a distributed configuration; a propeller operably connected to each of the hydraulic or electric motors, a source of hydraulic or electric power disposed within or attached to the frame and coupled to each of the disposed within or attached to the frame, wherein the source of hydraulic or electric power provides sufficient energy density for the craft to attain and maintain operations of the craft, a controller coupled to each of the hydraulic or electric motors, and one or more processors communicably coupled to each controller that control an operation and speed of the plurality of hydraulic or electric motors.

The present invention includes a distributed propulsion system for a craft that comprises a frame, a plurality of hydraulic or electric motors disposed within or attached to the frame in a distributed configuration; a propeller operably connected to each of the hydraulic or electric motors, a source of hydraulic or electric power disposed within or attached to the frame and coupled to each of the disposed within or attached to the frame, wherein the source of hydraulic or electric power provides sufficient energy density for the craft to attain and maintain operations of the craft, a controller coupled to each of the hydraulic or electric motors, and one or more processors communicably coupled to each controller that control an operation and speed of the plurality of hydraulic or electric motors.

A self-retaining wear-pad leveler has a first plate having arms on opposing sides and forming an aperture through the first plate. A rear section is coupled to a rear portion of the first plate and has tabs extending from opposing sides of the rear section. The arms are configured for being retained about a ball of a spherical bearing assembly, and the tabs are configured to cause rotation of the leveler about the bearing when engaged by a component coupled to and rotating about the bearing.