Abstract: A noise control system for a ducted rotor assembly, the ducted rotor assembly including a hub, a duct, and two or more blades coupled to the hub and supported by the duct. The noise control system including a microphone configured to receive a sound input generated by the ducted rotor assembly, the microphone configured for association with the hub; a speaker unit configured to generate a cancellation noise, the speaker configured for association with the hub; and a controller operably connected to the microphone and the speaker unit, the controller configured to selectively adjust harmonics of the cancellation noise to reduce an acoustic signature of the ducted rotor assembly. In another aspect, there is provided a rotorcraft with a ducted rotor assembly in a tail portion including a noise control system. In a third aspect, there is a method of reducing an acoustic signature of a ducted rotor assembly.

Abstract: A rotor blade including a root portion adapted to be connected to a helicopter rotor hub for rotation therewith, the root portion having a first edge surface; a first movable member having a first movable surface adjacent to the first edge surface; a first elastomeric joint disposed between the root portion and the first movable member, the first elastomeric joint having an inner surface facing the first edge surface of the root portion and an outer surface facing the movable surface of the first movable member; and an actuating system mounted within the root portion and the first movable member for moving the first movable member. The first elastomeric joint deforms to adjust for shear from actuation of the first movable member to a first position during helicopter mode; and to a second position during airplane mode.

Abstract: An adjustable balance module for the balancing of rotatable blades. The adjustable blade balance module includes a frame that retains and covers an adjustment screw with a mass that translates along a threaded shaft of the adjustment screw. The adjustment screw is incrementally controlled by an adjustment dial that is accessible from an exterior surface of the blade.

Abstract: A propulsion assembly for a rotorcraft includes a mast and a proprotor hub assembly coupled to the mast and having a gimballing degree of freedom relative to the mast. The propulsion assembly includes a gimbal lock assembly positioned about the mast and including a plurality of radially outwardly extending and circumferentially distributed rollers. The gimbal lock assembly is movable between a disengaged position and an engaged position relative to the proprotor hub assembly. In the disengaged position, the gimbal lock assembly enables the gimballing degree of freedom. In the engaged position, the rollers of the gimbal lock assembly contact the proprotor hub assembly to disable the gimballing degree.

Abstract: In a first aspect, there is a helicopter skid landing gear assembly including a front cross tube configured to interconnect two skid tubes; and a rear cross tube configured to interconnect two skid tubes; wherein at least one of the cross tubes comprises a monolithic metallic tube having a cross-section with a round exterior shape and an elliptical hollow portion therein. In a second aspect, there is a method for retrofitting a helicopter with a landing gear assembly; the method including providing a front cross tube and a rear cross tube, at least one of the front cross tube and the rear cross tube comprises a monolithic metallic tube having a cross-section with a substantially round exterior shape and an elliptical hollow portion therein; and connecting the front cross tube and rear cross tube to a fuselage.

Abstract: A hybrid composite reinforced ring gear minimizing radial deformation during high RPM conditions includes a composite backing secured to a metal rim. In use, at operating temperature the composite backing contracts while the metal rim expands thus creating a compressive stress on the metal rim and significantly reduces radial deformation due to centrifugal forces as compared to an all steel ring gear.

Abstract: A propulsion assembly for a rotorcraft includes a mast and a proprotor hub assembly coupled to the mast and having a gimballing degree of freedom relative to the mast. The proprotor hub assembly includes a hook receiver. The propulsion assembly includes a gimbal lock positioned about the mast. The gimbal lock includes a locking ring and a gimbal lock hook. The gimbal lock is movable between a disengaged position and an engaged position relative to the proprotor hub assembly. The gimbal lock enables the gimballing degree of freedom in the disengaged position and disables the gimballing degree of freedom in the engaged position. The gimbal lock hook is hooked to the hook receiver in the engaged position to secure the locking ring to the proprotor hub assembly.

Abstract: A hybrid composite and metallic gear includes a generally cylindrical shaft interface. A composite web is coupled to the shaft interface. The composite web includes a generally cylindrical rim having an outer surface. The outer surface includes a plurality of locks each having a radially outwardly extending profile. A generally cylindrical metallic gear ring having a plurality of external teeth includes an inner surface. The inner surface includes a plurality of detents each having a radially outwardly extending profile that corresponds with one of the locks of the composite web. When the composite web is positioned within the metallic gear ring, the corresponding locks and detents each form a lock and detent coupling establishing an interlocking interface between the composite web and the metallic gear ring.

Abstract: A wing airframe for a wing of a tiltrotor aircraft includes a wing airframe core assembly and a wing skin assembly disposed on the wing airframe core assembly. The wing skin assembly includes a lower wing skin assembly disposed on the bottom side of the wing airframe core assembly. The tiltrotor aircraft includes a fuselage underneath the wing. The lower wing skin assembly has one or more buckle zones outboard of the fuselage. The buckle zones are locally susceptible to buckling in response to an impact of the tiltrotor aircraft, thereby protecting the fuselage from being crushed by the wing.

Abstract: A rotorcraft includes a fuselage having a fuel tank receiving assembly with a fuel tank positioned therein. The fuel tank including a plurality of interconnected fuel bags operable to contain liquid fuel. A network of straps is disposed about the fuel tank forming a restraint assembly. The network of straps includes at least one perimeter strap extending at least partially about at least two fuel bags and at least one surrounding strap extending at least partially about the at least two fuel bags. The at least one perimeter strap has at least two intersections with the at least one surrounding strap.

Abstract: Some examples of a cable cutting system include a first cutting apparatus that includes a recess to receive a cable. The system includes a second cutting apparatus separate from and attached to the first cutting apparatus. The second cutting apparatus includes multiple cutting surfaces arranged to cut the cable received at the recess.

Abstract: An apparatus comprising a drivelink comprising a housing including a socket, wherein the socket comprises a cross-sectional area, and a bearing cartridge disposed within the socket, wherein a cross-sectional area of the cartridge is less than the cross-sectional area of the socket. An apparatus comprising a drivelink comprising a housing having a socket, and a bearing cartridge positioned within the socket and comprising a first portion and a second portion, wherein the first portion is configured to undergo compression when a load is applied to the drivelink, and wherein the second portion is configured to not be in tension when the load is applied to the drivelink.

Abstract: A wing pivot apparatus for rotating a wing between a flight orientation and a stowed orientation relative to a fuselage of a tiltrotor aircraft. The apparatus includes a stow ring that is rotatably mounted to the fuselage. Forward and aft wing attach assemblies are coupled respectively to forward and aft spars of the wing and are coupled to the stow ring. Forward and aft connecting assemblies are coupled respectively between the forward and aft wing attach assemblies and the stow ring and are selectively securable respectively to first and second fore-aft beams of the fuselage. A plurality of lock assemblies selectively secures the connecting assemblies to the fore-aft beams of the fuselage when the wing is in the flight orientation. An actuator coupled to the fuselage is operable to reversibly rotate the wing between the flight orientation and the stowed orientation.

Abstract: Systems and methods of prioritizing the use of flight attitude controls of aircraft operable to transition between thrust-borne lift in a VTOL orientation and wing-borne lift in a biplane orientation. A method includes determining an optimal flight attitude state for the aircraft during flight, the aircraft including first and second wings with first and second pylons coupled therebetween forming an airframe with a two-dimensional distributed thrust array and a plurality of aerosurfaces coupled to the airframe; monitoring the current flight attitude state of the aircraft; identifying deviations between the current flight attitude state and the optimal flight attitude state; ordering the flight attitude controls of the aircraft based upon the flight attitude control authority of each in the current flight attitude state; and implementing the highest order flight attitude control to bias the aircraft from the current flight attitude state toward the optimal flight attitude state.

Abstract: A foldable wing system for an unmanned aerial system having a fuselage includes a left wing frame having an inboard gear rotatably coupled to the fuselage, a right wing frame having an inboard gear rotatably coupled to the fuselage and a wing actuator coupled to a linkage point on at least one of the wing frames. The wing frames are movable between a plurality of positions including a deployed position and a stowed position. The inboard gear of the left wing frame is engaged with the inboard gear of the right wing frame such that the wing frames move symmetrically between the plurality of positions in response to movement of the linkage point by the wing actuator.

Abstract: An aircraft includes an airframe having first and second wings with first and second pylons extending therebetween and having a two-dimensional distributed thrust array of outboard propulsion assemblies attached thereto. A flight control system is coupled to the airframe and is operable to independently control a rotor speed and a thrust vector of each propulsion assembly. In a low thrust to weight configuration, transitions from the VTOL orientation to the biplane orientation include establishing a pitch down flight attitude while engaging in collective thrust vectoring of the outboard propulsion assemblies to maintain hover stability followed collectively reducing the thrust vector angles to initiate forward flight. In a high thrust to weight configuration, transitions from the VTOL orientation to the biplane orientation include maintaining a level flight attitude while collectively increasing the thrust vector angles of the outboard propulsion assemblies to initiate forward flight.

Abstract: A method for facilitating the design and manufacturing of a tiltrotor aircraft, including the steps of: determining a compatible mission data set; identifying lift propulsion module components for the compatible mission data set; determining compatible specifications; and generating a design for a lift propulsion module; wherein the lift propulsion module is configured to be connected to at least two different fuselages. There is also a method of designing a tiltrotor aircraft, comprising the step of modularizing a lift propulsion system, wherein the lift propulsion system is configured to be connected to at least two different fuselages. In another aspect, there is a tiltrotor aircraft including a fuselage; and a lift propulsion module, the lift propulsion module including a mounting surface; wherein the lift propulsion module is coupled to the fuselage on the mounting surface. Also included are methods of assembling and systems including a lift propulsion module.

Abstract: An aerial imaging aircraft operable to transition between thrust-borne lift in a VTOL orientation and wing-borne lift in a biplane orientation. The aircraft includes an airframe having first and second wings with first and second pylons coupled therebetween. The airframe has a longitudinal axis and a lateral axis in the VTOL orientation. A two-dimensional distributed thrust array is coupled to the airframe. The thrust array includes a plurality of propulsion assemblies each operable for variable speed and omnidirectional thrust vectoring. A payload is coupled to the airframe and includes an aerial imaging module. A flight control system is operable to independently control the speed and thrust vector of each of the propulsion assemblies such that in a level or inclined flight attitude, the flight control system is operable to maintain the orientation of the aerial imaging module toward a focal point of a ground object while translating the aircraft.

Abstract: A propulsion assembly for an aircraft includes a nacelle having a rapid connection interface, at least one battery disposed within the nacelle, a speed controller coupled to the battery and a propulsion system coupled to the speed controller and the battery. The propulsion system includes an electric motor having an output drive and a rotor assembly having a plurality of rotor blades that are rotatable with the output drive of the electric motor in a rotational plane to generate thrust. The electric motor is operable to rotate responsive to power from the battery at a speed responsive to the speed controller. The rapid connection interface of the nacelle is couplable to a rapid connection interface of an airframe nacelle station to provide structural and electrical connections therebetween that are operable for rapid in-situ assembly.

Abstract: An aircraft having a vertical takeoff and landing flight mode and a forward flight mode. The aircraft includes a fuselage and a dual tiltwing assembly having a vertical lift orientation and a forward thrust orientation relative to the fuselage. The dual tiltwing assembly includes a forward wing and an aft wing coupled together and to the fuselage by a quadrilateral linkage. A distributed propulsion system is coupled to the dual tiltwing assembly and includes a plurality of forward propulsion assemblies coupled to the forward wing and a plurality of aft propulsion assemblies coupled to the aft wing. A flight control system is operably associated with the distributed propulsion system and the dual tiltwing assembly. The flight control system is operable to independently control each of the propulsion assemblies and is operable to transition the dual tiltwing assembly between the vertical lift orientation and the forward thrust orientation.