Abstract: A rotary wing aircraft includes an airframe, a stationary mast fixedly engaged to the airframe and extending along a first axis, and an electric motor. The electric motor includes a stator assembly engaged to the mast and a rotor assembly disposed radially outward from the stator assembly and configured to rotate with respect to the stator assembly. A plurality of rotor blades project radially outward from the rotor assembly.

Abstract: A rotor system includes a rotor hub, a plurality of rotor blades supported by the rotor hub, and a fairing mounted to the rotor hub. The fairing includes an external surface exposed to an external airflow and an internal surface defining an interior portion. One or more heat generating components are arranged in the interior portion. A cooling system is arranged in the interior portion. The cooling system includes a first heat exchanger thermally connected to each of the one or more heat generating components, a second heat exchanger mounted to the fairing, and at least one fluid conduit extending therebetween so as to remove heat generated by each of the one or more heat generating components.

Abstract: According to one aspect, a lubricant level sensing system for an actuator is provided. The lubricant level sensing system includes a pressure port in an outer housing of the actuator, a pressure sensor, and a pathway from the pressure port to the pressure sensor. The pathway establishes fluid communication between the pressure sensor and a free volume of an internal cavity of the outer housing relative to a lubricant level in the internal cavity such that the pressure sensor detects a pressure of the free volume used to derive the lubricant level.

Abstract: A lubrication system for a transmission includes a flow-metering device and a controller. The controller is operatively associated with the flow-metering device to cause the flow-metering device to intermittently issue lubricant from the flow-metering device into a transmission based on an operating parameter of the transmission.

Abstract: A bond fixture includes a first fixture having a heater and a plurality of clamps. Each of the plurality of clamps includes a first member and a second member rotatable between a first position and a second position. A second fixture includes a root end lift translatable vertically between a retracted position and an extended position and a root end clamp translatable along a horizontal axis. The root end clamp is configured to cooperate with the root end.

Abstract: An airbag system includes a VTOL aircraft fuselage having an airbag compartment defined within the fuselage. A protective cover defines a portion of the exterior surface of the fuselage. The protective cover encloses at least a portion of the airbag compartment. An airbag is folded within the airbag compartment secured to a point on the fuselage. A method for deploying an airbag in an aircraft includes sending a signal to a gas generator to inflate at least one airbag secured within an airbag compartment within a fuselage of an aircraft. The method includes jettisoning off a protective cover from the airbag compartment. The method includes inflating the airbag with the gas generator to extend outside of the airbag compartment to attenuate forces and cushion the aircraft upon ground impact.

Abstract: A gear train includes a first gear having teeth meshed with teeth of a second gear. Each tooth of the first gear includes a coast side and a drive side opposed to the coast side. The drive side has a pressure angle that is greater than that of the coast side. The gear train can be part of a powertrain system for a rotorcraft, and can replace a traditional gear train in a retrofit or new build. The first gear is a planet gear and the second gear is a ring gear wherein the planet gear and ring gear are in a planetary gear train configuration.

Abstract: A drive system for a rotorcraft includes at least one engine, the engine including a compressor section, and a turbine section positioned rearward from the compressor section. A main rotor input shaft extends from a rotor power turbine of the turbine section and is connectable to a main rotor assembly of the rotorcraft to transfer rotational energy from the rotor power turbine to the main rotor assembly. An auxiliary input shaft extends from an auxiliary power turbine of the turbine section and is connectible to an auxiliary rotor assembly of the rotorcraft to transfer rotational energy from the auxiliary power turbine to the auxiliary rotor assembly.

Abstract: A vibration control assembly for an aircraft including a housing operatively coupled to the aircraft. Also included is a cage disposed within an interior region of the housing, the cage rotatable within the housing about a first axis. Further included is a gyroscope wheel disposed within the cage and rotatable about a second axis other than the first axis, wherein a controllable moment is imposed on the aircraft upon rotation of the gyroscope wheel to counter vibratory moments produced by the vehicle.

Abstract: A retractable landing gear system for a vertical takeoff and landing (VTOL) aircraft includes a rotational strut rotatably coupled to a fuselage of the VTOL aircraft. The rotational strut includes a first end, a second end, and an intermediate portion extending therebetween. A drag strut includes a first end portion pivotally connected to the rotational strut and a second end portion. A locking link includes a first end section pivotally connected relative to the fuselage, a second end section pivotally connected to the drag strut and an intermediate section having a hinge element. A retraction system is operatively connected to the rotational strut and the locking link. The retraction system is operable to pivot the drag strut about a first axis and rotate the rotational strut about a second axis that is distinct from the first axis.

Abstract: An assembly configured to prevent damage to an object during manufacture thereof is provided including a first housing having a substantially hollow interior. An exposed first planar surface of the first housing includes an inlet port and a plurality of small openings formed about the periphery. The inlet port, the hollow interior, and the plurality of small openings form a fluid flow path through the assembly. A second housing similar in size and shape to the first housing, has an exposed second planar surface. An intermediate layer is arranged between the first housing and the second housing. A cross-section of the intermediate layer is configured to change shape in response to a compression force applied thereto by the first housing and the second housing to form a seal separating an exterior portion of the objection exposed to the plurality of small openings from an interior surface of the object.

Abstract: A system for regenerating fastener holes in a replacement tip section of a rotor blade includes a first fixture, a second fixture, and a third fixture positionable adjacent a tip section of the rotor blade. The first fixture is used to verify a position of an opening formed in the spar. The second fixture includes a removable bushing having a drillable opening. The drillable opening is aligned with the at least one opening formed in the spar and defines at least one hole to be formed in the replacement tip section. The third fixture includes a countersink opening. The countersink opening is aligned with the at least one hole to be formed in the replacement tip section and the at least one opening formed in the spar to define a countersink feature to be formed in the at least one hole.

Abstract: A flexible coupling includes a first disc and a second disc arranged along a rotation axis. The first disc and the second disc each include a radially inner hub portion, a radially outer rim portion, and a diaphragm portion extending between the hub portion and the rim portion. The first disc rim portion is connected to the second disc rim portion and the first disc has a diametral response mode that is different than a diametral response mode of the second disc to limit deformation in the flexible coupling when communicating rotation between a drive member and a driven member connected to one another by the flexible coupling. Drive trains and methods of making flexible couplings are also described.

Abstract: A method of fabricating a composite structure includes laying at least one composite ply about a bladder, the bladder comprising a phase change material in a first phase having a first volume, positioning an outer mold about the bladder and the at least one composite ply, and curing the at least one composite ply to form the composite structure. Curing causes the phase change material contained within the bladder to change to a second phase to expand from the first volume to a second volume and apply a pressure to an interior surface of the composite ply and press an outer surface of the composite ply against the outer mold to form an interior cavity. The bladder is not removable from the formed interior cavity.

Abstract: An axial preloading device can include a shell having an inner surface that defines a radially interior channel, the inner channel defining an axial direction, one or more moveable housing members disposed at least partially within the interior channel and configured to move relative to the shell in the axial direction, and a wedge assembly connected to the shell and disposed in contact with the one or more housing members. The wedge assembly can be configured to be moved radially relative to the shell and the one or more housing members to push the one or more housing members axially. The wedge assembly and the one or more housing members define a shaft opening when installed on the shell.

Abstract: A method for securing an engine using an adjustable mounting assembly is provided including adjusting an extendible element of the adjustable mounted assembly from a first position to a second position. Another extendible element of the adjustable mounting assembly is adjusted from a third position to a fourth position. The engine is mounted using the adjustable mounted assembly with the extendible element in the second position and another extendible element in the fourth position.

Abstract: A solid lubricant-carrying gear which is lubricated by a liquid lubricant communicated to the gear by a primary lubrication system includes a gear body and a solid lubricant body. The gear body is arranged along a rotation axis and has a first surface, an axially opposite second surface, and an outward radial face extending about the rotation axis having gear teeth and lubricant directing features. The solid lubricant body is coupled to the gear body and includes a lubricant which melts at a melting temperature above that of the liquid lubricant to provide secondary lubrication to the gear via the lubricant directing features. Gearboxes, aircraft having transmissions employing solid lubricant-carrying gears, and methods of lubricating gears are also described.

Abstract: An aircraft rotor blade assembly includes a rotor blade rotatable about an axis of rotation and a weighted assembly mounted to the aircraft rotor blade. The weighted assembly includes an actuator which moves a mass to adjust a moment of the rotor blade assembly when the rotor blade is rotated about the axis of rotation.

Abstract: A flexbeam rotor blade assembly includes a flexbeam having a body that includes a first surface, a second, opposing surface, and an opening extending through the first and second surfaces. At least one snubber is mounted to one of the first and second surfaces spaced along the body from the opening. A snubber retainer is mounted to one of the first and second surfaces between the body and the at least one snubber. The snubber retainer includes a retainer plate having a snubber attachment member to which the snubber assembly is mounted and a mounting arm including a retainer plate opening spaced from the snubber attachment member. The retainer plate opening registers with the opening in the flexbeam. A mechanical fastener extends through the retainer plate opening and the opening in the flexbeam. The mechanical fastener joins the snubber retainer to the one of the first and second surfaces.

Abstract: A rotor blade disassembly method includes applying spanwise support to a rotor blade body and heating a bond disposed on an end of the rotor blade body. The method also includes removing the spanwise support from the rotor blade body and exerting shear stress on the bond using weight of the rotor blade body. A blade disassembly system is also described.