Abstract: In some embodiments, a propulsion assembly for an aircraft includes a nacelle, at least one self-contained fuel tank disposed within the nacelle operable to contain a liquid fuel, an engine disposed within the nacelle operable to run on the liquid fuel, a drive system mechanically coupled to the engine and operable to rotate responsive to rotation of the engine, a rotor hub mechanically coupled to the drive system operable to rotate responsive to rotation of the drive system and a proprotor mechanically coupled to the rotor hub and operable to rotate therewith.

Abstract: A modal restraint system for an occupant of a seat of an aircraft includes a strap feeder unit and a strap selectively retractable into and extendable from the strap feeder unit. The strap is positionable adjacent to the occupant so as to dispose the occupant between the strap and the seat. The strap feeder unit is adapted to switch between a plurality of modes including an unfixed mode and a fixed mode. The strap is extendable from and retractable into the strap feeder unit in the unfixed mode. The strap is substantially unextendable from the strap feeder unit in the fixed mode. The strap feeder unit is in the unfixed mode by default. The strap feeder unit is operable to switch to the fixed mode in response to a precautionary event, thereby reducing freedom of movement of the occupant relative to the seat of the aircraft.

Abstract: A modal restraint system for an occupant of a seat of an aircraft includes a strap feeder unit and a strap selectively retractable into and extendable from the strap feeder unit. The strap is positionable adjacent to the occupant so as to dispose the occupant between the strap and the seat. The strap feeder unit is adapted to switch between a plurality of modes including a fixed mode and an unfixed mode. The strap is substantially unextendable from the strap feeder unit in the fixed mode. The strap is extendable from and retractable into the strap feeder unit in the unfixed mode. The strap feeder unit is in the fixed mode by default. The strap feeder unit is operable to switch to the unfixed mode in response to a user input, thereby increasing freedom of movement of the occupant relative to the seat of the aircraft.

Abstract: A rotor hub assembly for a rotorcraft includes a yoke forming a bearing bore. The yoke has a teetering axis extending through the bearing bore. The rotor hub assembly includes a flapping bearing disposed in the bearing bore. The flapping bearing is operable to regulate teetering of the yoke about the teetering axis. The rotor hub assembly includes an axial spring abutting the flapping, thereby reducing movement of the flapping bearing along the teetering axis.

Abstract: A seat footrest includes a footpad having a supporting plate under a cushioned top side, an arcuate member mechanically coupled to the plate by a first end and pivotally coupled to a seat frame by a second end. The arcuate member is adapted for pivoting the footpad between a stowed position and one or more deployed positions. A lock pin is provided for releasably inserting into a first notch of the arcuate member for securing the footpad in the stowed position and one or more additional notches of the arcuate member for securing the footpad in the one or more deployed positions. A first biasing member is adapted for initiating deployment of the footpad upon release of the lock pin from the first notch, and a second biasing member is adapted for completing deployment of the footpad by raising the footpad to the one or more deployed positions.

Abstract: An oscillating pump system includes a pump operable to circulate a fluid. The pump has a first port stage including an inlet port and an outlet port and a second port stage including a first oscillating port and a second oscillating port. An oscillator disk is disposed between the first port stage and the second port stage. The oscillator disk is rotatable relative to the inlet port, the outlet port, the first oscillating port and the second oscillating port. During rotation, the oscillator disk alternatingly routes the fluid to the inlet port from the first and second oscillating ports and alternatingly routes the fluid from the outlet port to the first and second oscillating ports, thereby generating oscillating fluid flow.

Abstract: Disclosed is a brake system for aircraft that uses a control unit that is configured to control actuators at each wheel using one channel operating an associated brake control module, and other actuators at the same wheel using a second module operated completely independently using a second module. The use of the first and second groups of actuators are alternated periodically, e.g., for each flight.

Abstract: An aircraft fuel system includes one or more fuel cells adapted to contain fuel, a fuel cell receiving assembly having an inner surface adapted to receive the one or more fuel cells and a fuel cell cushion disposed between the inner surface of the fuel cell receiving assembly and the one or more fuel cells. The fuel cell cushion is machined from a foam substrate to form a shaped foam substrate that is substantially covered with a cushion coating. The cushion coating is sprayable onto the shaped foam substrate such that the fuel cell cushion is substantially nonabsorbent of fuel. The fuel cell cushion is interposable between the inner surface of the fuel cell receiving assembly and the one or more fuel cells to cushion the one or more fuel cells from damage.

Abstract: According to one embodiment, a rotorcraft includes a body, a rotor blade, a drive system that can be operated to rotate the rotor blade, and an emergency valve control unit. The drive system contains a first gearbox assembly, a second gearbox assembly, a first lubrication system that can deliver lubricant to the first gearbox assembly, and a second lubrication system that can deliver lubricant to the second gearbox assembly. The drive system also contains an emergency valve that can be opened to deliver lubricant from the first lubrication system to the second gearbox assembly. The emergency valve control unit can instruct the emergency valve to open.

Abstract: A braking system for a rotorcraft having a rotor hub assembly includes a generator having an armature mechanically coupled to the rotor hub assembly such that the armature is rotatable in response to rotation of the rotor hub assembly and a braking unit in selective electrical communication with the generator. The braking unit is adapted to apply an electrical resistance to rotation of the armature, thereby reducing a rotational speed of the rotor hub assembly.

Abstract: The invention relates to a method for producing a tank from thermoplastic material, comprising the following method steps: extruding or providing a hose-like parison composed of plasticized thermoplastic material, and dividing and spreading the parison into two areal extrudate webs, or extruding or providing two parisons in web form, laying-in and molding the parisons in recesses of a multi-part blow-molding tool using differential pressure, wherein the recesses of the blow-molding tool delimit a mold cavity, punching out, or cutting out in a circular shape, at least one opening in at least one shell-like intermediate product, wherein the opening is produced by way of a punching or cutting tool which penetrates through a wall of one of the shell-like intermediate products, wherein in a second separate method step, a first attachment element of a line connection or of a line arrangement is welded, at the mold cavity side, to the wall of the shell-like intermediate product, in such a way that an encircling

Abstract: A tri-wing aircraft includes a fuselage having a longitudinally extending fuselage axis. Three wings extend generally radially outwardly from the fuselage axis and are circumferentially distributed generally uniformly about the fuselage at approximately 120-degree intervals. The wings have airfoil cross-sections including first and second surfaces having chordwise channels therebetween. A distributed propulsion system includes a plurality of propulsion assemblies. Each propulsion assembly includes a variable thrust cross-flow fan disposed within one of the chordwise channels of one of the wings. At least two variable thrust cross-flow fans are disposed within the chordwise channels of each of the wings. A flight control system is operably associated with the distributed propulsion system such that the flight control system and the distributed propulsion system are operable to generate a triaxial dynamic thrust matrix.

Abstract: The invention refers to integrated on-board vehicle vision and cleaning system comprising a casing being mounted in a vehicle bodywork, a viewing camera and a cleaning fluid nozzle associated with a nozzle carrier and communicating with a cleaning fluid source. The nozzle carrier is integrated into the casing and is moveable within the casing between first and second positions, the first position being a retracted position and the second position being an extended position which is the operating position. The nozzle carrier is designed as a sleeve encompassing the sensor unit.

Abstract: A stacked motor assembly for an aircraft includes a forward motor having an exhaust port and an aft motor disposed aft of the forward motor, the aft motor having an intake port. The stacked motor assembly includes an exhaust conduit originating from the exhaust port of the forward motor and disposed at least partially around the aft motor such that exhaust from the forward motor bypasses the aft motor. The stacked motor assembly also includes an intake conduit terminating at the intake port of the aft motor and disposed at least partially around the forward motor such that intake air for the aft motor bypasses the forward motor.

Abstract: An 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 hover. 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 flight control system is operable to independently control the speed and thrust vector of each of the propulsion assemblies such that in an inclined flight attitude with at least one of the longitudinal axis and the lateral axis extending out of a horizontal plane, the flight control system is operable to maintain hover stability responsive to controlling the speed and the thrust vector of the propulsion assemblies.

Abstract: A quad tiltrotor aircraft has a longitudinally extending fuselage with forward and aft stations. A forward wing having first and second outboard ends extends laterally from the forward station. An aft wing having first and second outboard ends extends laterally from the aft station. First and second forward rotors are respectively coupled proximate the first and second outboard ends of the forward wing and are tiltable relative to the forward wing between vertical lift and forward thrust orientations. First and second aft rotors are respectively coupled proximate the first and second outboard ends of the aft wing and are tiltable relative to the aft wing between vertical lift and forward thrust orientations. The forward rotors are higher disk-loading rotors than the aft rotors. The aft rotors are foldable in the forward flight mode to provide extended range for the quad tiltrotor aircraft.

Abstract: In one aspect, there is a method of making a pre-cured laminate having a total number of plies in a mold, the mold having a cavity with a periphery defined by a forward edge, an aft edge, and outboard ends. The method includes selecting a first plurality of resin impregnated plies that continuously extend beyond the periphery of the cavity, the first plurality of resin impregnated plies includes at least 50 percent of the total number of plies; laying the plies in a mold; compacting the plies in a mold; and pre-curing the plies to form a pre-cured laminate, which can extend beyond the periphery of the cavity. In an embodiment, a pre-cured laminate includes a first plurality of resin impregnated plies that continuously extend beyond the periphery of the cavity.

Abstract: A tiltrotor assembly has a central hub with a plurality of rotor blades extending therefrom and is configured to rotate about a mast axis to generate lift in a hover position. The central hub is configured to rotate about a tilt axis between the hover position and a forward-flight position such that rotation about the mast axis generates forward thrust. The central hub is surrounded by a segmented duct that includes a thin rotatable inner ring and a wide fixed outer ring. The inner ring is configured to rotate with the central hub about the tilt axis leaving the wide outer ring in a generally horizontal position.

Abstract: A method of performing structural analysis relating to a component having CAD-based geometry, refined CAD-based geometry and CAD-based FEA data associated therewith. The method includes scanning the component to obtain scan-based point cloud geometry of the component, aligning the scan-based point cloud geometry with the CAD-based geometry of the component, generating scan-based geometry of the component by refining the scan-based point cloud geometry, comparing the scan-based geometry with the refined CAD-based geometry of the component to quantify geometric differences therebetween, generating scan-based FEA geometry of the component by meshing the scan-based geometry, performing finite element analysis on the scan-based FEA geometry to obtain scan-based FEA data and comparing the scan-based FEA data with the CAD-based FEA data of the component to quantify the effect of geometric difference therebetween.