A propeller, a propeller kit, a power assembly, a power kit and an unmanned aerial vehicle (UAV). The propeller includes a hub and at least two blades connected to the hub. The hub is detachably mounted on a corresponding drive apparatus by a mounting member corresponding to the hub, so that the propeller is mounted on the corresponding drive apparatus. A surface, facing the mounting member, of the hub is provided with a first fitting portion. A surface, facing the hub, of the mounting member is provided with a second fitting portion corresponding to the first fitting portion. The first fitting portion matches the second fitting portion. In the foregoing manner, a user can be prevented from incorrectly mounting a forward propeller and a counter-rotating propeller during the use of a quick-detachable propeller in the embodiments of the present application.

The present invention provides an engine of a vertical take-off and landing aircraft, wherein the engine is configured to be movable with respect to an aircraft component of the aircraft between a hover position for take-off and landing, and a cruise position for forward flight, wherein the engine comprises an aerodynamic component having at least one aerodynamic element movable between a first position and a second position the aerodynamic element defining an aerodynamic surface in contact with an airstream passing through the engine.

A system and method of an airflow control system for a vehicle is described herein. The airflow control system (100) includes an airflow housing (120) defining an airflow passageway (125) extending between a bypass opening (122) and an intake outlet (124). The airflow housing also defines a duct opening (126) positioned between the bypass opening (122) and the intake outlet (124). The intake outlet (124) may be in fluid communication with an engine intake (12) of the vehicle such that air passes from the bypass opening (122) and/or the duct opening (126) to the engine intake (12). The airflow control system (100) also includes a movable duct (160) movably connected to the airflow housing (120) to selectively allow or prevent air passage through the duct opening (126) and into the engine intake (12), and further includes a bypass door (140) movably connected to the airflow housing (120) to selectively allow or prevent air passage through the bypass opening (122) and into the engine intake (12).

The present invention relates generally to propulsion systems and, more specifically, to propulsion systems configured to vector and provide directional thrust such as those that may be used in aircraft or watercraft. Such propulsion systems may be used in connection with unmanned aerial vehicles, other aircraft, or various watercraft including submersibles.

A swashplate assembly of a rotary wing aircraft includes a first component, a second component arranged concentrically with the first component, and a bearing disposed between the first component and the second component. The bearing includes a spherical bearing and at least one bearing roller element and is operable to transmit torque between the first component and the second component.

A blade pitch adjustment mechanism includes a pitch cylinder having a first face and pitch slots extending longitudinally from the first face, a blade sleeve having a second face and a blade slot extending longitudinally from the second face, the blade sleeve is configured to be rotationally positioned in the pitch cylinder with the second face located with the first face, wherein the blade slot and the pitch slots are cooperative to form keyway, corresponding to a discrete blade pitch, when the blade slot is aligned with a pitch slot.

An exemplary pitch link centering tool includes a rod having a longitudinal axis, a front face, a rear face, a first rod end and a second rod end, the first rod end having a first aperture with a first rotational axis, the second rod end having a second aperture with a second rotational axis, a first connector coupled to the first rod end, the first connector having a first slot extending in a first radial direction relative to the longitudinal axis and a second connector coupled to the second rod end, the second connector having a second slot extending in a second radial direction relative to the longitudinal axis different from the first radial direction.

One embodiment is a rotor system comprising a duct ring; a hub disposed centrally to the duct ring; first and second stators each connected between the duct ring and the hub; first and second control vanes rotatably connected to the first and second stators, respectively; a structural hoop having a first end connected to the first control vane and a second end connected to the second control vane, the structural hoop for translating rotation of the first control vane about a vane axis to the second control vane; and a mechanism for restricting at least one of forward-aft movement and side-to-side movement of the structural hoop relative to the duct ring.

Embodiments of the disclosure are directed to a ducted fan engine configured for providing thrust for an aircraft, in particular an aircraft having vertical take-off and landing capability. The ducted fan engine includes a shroud, a stator, and a rotor rotatably supported by the shroud. The shroud has a substantially circular cross-section. The stator has at least one substantially radially-extending stator vane. The rotor comprises at least 19 rotor blades, in particular at least 25 rotor blades.

The present invention comprises a novel autorotation safety device consisting of at least one compressed air tank that is configured to release high velocity air, either autonomously or through the actions of a pilot, into a thrust producing flywheel/rotor when the primary drive source for the rotors/fans have failed, creating a secondary drive system for safety. In preferred embodiments, when the primary drive system fails, and the air vehicle starts to descend, the invention will automatically inject high pressure air into the propulsion system's blades to create the thrust necessary to soften an emergency landing.