Abstract: A bearing assembly comprises a bearing, a shim disposed within the bearing, and a component disposed within the shim. The shim comprises a first material, the component comprises a second material, and the first material has an elastic modulus value that is lower than an elastic modulus value of the second material. An apparatus comprises an elastomeric bearing, a fiberglass shim, and a steel spindle that is connected to the elastomeric bearing through the shim. A method for reducing strain in an adhesive layer that connects a bearing to a component comprises selecting a shim material having an elastic modulus value that is less than an elastic modulus value of the component and providing instructions to connect the component to the shim by placing the adhesive layer between an outer surface of the component and an inner surface of the shim.

Abstract: A rotor assembly for a rotary-wing aircraft, the rotor having a central hub assembly with a flexure-type, twist-shank yoke with multiple arms, each arm being adapted for a rotor blade to be mounted thereto. The arms provide for pitch changes of blades attached to the yoke through twisting of portions of the arms about a corresponding pitch axis. An inboard pitch bearing associated with each arm is attached to the hub assembly and allows for rotation of the attached blade about the pitch axis, the inboard pitch bearing also allowing for out-of-plane motion of the arm relative to the hub assembly about a flapping axis. An outboard pitch bearing associated with each arm is attached to the associated arm a selected distance from the inboard pitch bearing and allows for rotation of the attached blade about the pitch axis.

Abstract: A system and algorithm-based method of determining engine health and assuring available propulsion power based on historical data reflecting the individual engine's unique performance “fingerprint.

Abstract: A pedestal assembly receives a pylon assembly of a tiltrotor aircraft having an airframe including a fuselage and a wing. The pedestal assembly includes inboard and outboard tip ribs that extend above the wing and respectively define inboard and outboard slots. The pedestal assembly also includes inboard and outboard bearing cartridges. The inboard bearing cartridge is received within the inboard slot, is coupled to the inboard tip rib and includes an inboard bearing assembly. The outboard bearing cartridge is received within the outboard slot, is coupled to the outboard tip rib and includes an outboard bearing assembly. The inboard and outboard bearing assemblies are operable to receive the pylon assembly therein such that the pylon assembly is rotatably mounted between the inboard and outboard tip ribs to selectively operate the tiltrotor aircraft between a helicopter mode and an airplane mode.

Abstract: In some embodiments, a rotorcraft may include a yoke, a blade, a spindle associated with the yoke, and an elastomeric bearing assembly. The center length of the spindle may define a center axis that passes through a center of the elastomeric bearing assembly. The elastomeric bearing assembly may contain a housing coupled to the blade and disposed around the center axis that is configured to rotate in relation to the center axis. The elastomeric bearing assembly may contain an elastomeric shear bearing that has an interior portion coupled to the spindle and an exterior portion coupled to the housing. The elastomeric bearing assembly may contain an elastomeric centrifugal force bearing pressed against the housing. The shear bearing may be configured to counteract a torsional force, and the centrifugal force bearing may be configured to counteract a compression force.

Abstract: A propulsion system for a tiltrotor aircraft includes an engine supported by the airframe and a fixed gearbox operably coupled to the engine. Inboard and outboard pedestals are supported by the airframe and positioned above the wing. A pylon assembly is rotatably coupled between the inboard and outboard pedestals. The pylon assembly includes a spindle gearbox having an input gear, a mast operably coupled to the input gear and a proprotor assembly operable to rotate with the mast. The spindle gearbox is rotatable about a conversion axis to selectively operate the tiltrotor aircraft between helicopter and airplane modes. A common shaft, rotatable about the conversion axis, is configured to transfer torque from an output gear of the fixed gearbox to the input gear of the spindle gearbox. Each of the inboard and outboard pedestals includes a journal bearing that provides a stiff coupling with the pylon assembly.

Abstract: A method of increasing the control authority of redundant stability and control augmentation system (SCAS) actuators by utilizing feedback between systems such that one system may compensate for the position of a failed actuator of the other system. Each system uses an appropriate combination of reliable and unreliable inputs such that unreliable inputs cannot inappropriately utilize the increased authority. Each system may reconfigure itself when the other system actuator fails at certain positions so that the pilot or other upstream input maintains sufficient control authority of the aircraft.

Abstract: A propulsion system for a tiltrotor aircraft includes an engine supported by the airframe and a fixed gearbox operably coupled to the engine. Inboard and outboard pedestals are supported by the airframe and positioned above the wing. A pylon assembly is rotatably coupled between the inboard and outboard pedestals. The pylon assembly includes a spindle gearbox having an input gear, a mast operably coupled to the input gear and a proprotor assembly operable to rotate with the mast. The spindle gearbox is rotatable about a conversion axis to selectively operate the tiltrotor aircraft between helicopter and airplane modes. A common shaft, rotatable about the conversion axis, is configured to transfer torque from an output gear of the fixed gearbox to the input gear of the spindle gearbox. Each of the inboard and outboard pedestals includes a pillow block housing such as a full or a split pillow block housing.

Abstract: According to one embodiment, an aircraft part storage system includes a first storage device and a second storage device. The first storage device is configured to be coupled to an aircraft part and operable to store and transmit a first set of information about the aircraft part. The second storage device is configured to be coupled to the same aircraft part and operable to store and transmit a second set of information about the aircraft part. The second storage device has a larger storage capacity than the first storage device but a shorter transmission range than the first storage device.

Abstract: A composite structure includes a first face sheet, a second face sheet, and a foam member located between the first face sheet and the second face sheet. The foam member has a molded contour, the mold contour being configured to provide tooling surface for at least one of the first face sheet and the second face sheet prior to curing of the composite structure. A method of making the foam member includes creating a mold tool having an interior surface which resembles the desired outer contour of the foam member. A mixture is poured into a pour opening in the mold tool. The mixture is allowed to polymerize into a foam as the foam expands and distributes within the mold tool. Vent openings in the mold tool are selectively tailored to control the density of the foam member. The foam member is cured in the mold tool.

Abstract: A rotorcraft autopilot system includes a series actuator connecting a cockpit control component to a swashplate of a rotorcraft, the series actuator to modify a control input from the cockpit control component to the swashplate through a downstream control component. The rotorcraft autopilot system also includes a differential friction system connected to the cockpit control component, the differential friction system to control the series actuator to automatically adjust a position of the cockpit control component during rotorcraft flight based, in part, on a flight mode of the rotorcraft.

Abstract: A continuously variable transmission housing is provided that includes an inner cover and an outer cover connectable to the inner cover to define an interior chamber. The interior chamber is structured and operable to enclose a continuously variable transmission primary pulley, secondary pulley and pulley belt. The housing includes a duct panel mounted to the inner cover such that when the primary pulley is disposed within the interior chamber, the duct panel is disposed between an outer face of the primary pulley and the inner cover. Moreover, an air duct is defined between the inner cover and the duct panel, wherein the air duct is fluidly connected to ambient air from an ambient environment external to the housing. The duct panel includes a center opening that structured and operable to allow the ambient air to be drawn through the air duct and into the housing interior chamber.

Abstract: Embodiments of the present disclosure relate to an Operational Flight Efficiency Evaluation (OFEE) system for an aircraft. The system comprises an Avionics Situation Awareness Device (ASAD). The ASAD includes one or more processors, a memory communicatively coupled to the one or more processors, and a flight data collection interface configured to, via the one or more processors, collect empirical flight data for a flight and store the empirical flight data in the memory. The OFEE also includes a Simulation And Comparison System (SACS) in communication with the ASAD. The ASAD includes a database communicatively coupled to a National Airspace System (NAS). The database is also configured to automatically acquire and store avionics systems available for flight efficiencies from the NAS. The ASAD also includes a simulator configured to identify at least one avionics upgrade based on the collected empirical flight data and the avionics systems available for flight efficiencies.

Abstract: In some embodiments, a transportation method includes coupling a flying frame to a passenger pod assembly; lifting the passenger pod assembly into the air in a vertical takeoff and landing mode with the passenger pod assembly in a generally horizontal attitude; transitioning from the vertical takeoff and landing mode to a forward flight mode by rotating the flying frame relative to the passenger pod assembly, which remains in the generally horizontal attitude; transporting the passenger pod assembly toward a second location in the forward flight mode; transitioning the flying frame from the forward flight mode to the vertical takeoff and landing mode by rotating the flying frame relative to the passenger pod assembly, which remains in the generally horizontal attitude; landing the flying frame at the second location in the vertical takeoff and landing mode; and releasing the passenger pod assembly.

Abstract: In some embodiment, an aircraft includes an airframe, a propulsion system attached to the airframe and a flight control system operably associated with the propulsion system. A pod assembly is selectively attachable to the flying frame. The flying frame has a vertical takeoff and landing mode and a forward flight mode. The flying frame has a manned flight mode and an unmanned flight mode.

Abstract: In one aspect, there is a method of making a composite skin for a tiltrotor aircraft including providing a first skin in a mold, the first skin having a periphery defined by a forward edge, an aft edge, and outboard ends; providing a plurality of honeycomb panels having an array of large cells onto the first skin, each cell having a width of at least 1 cm; assembling the plurality of honeycomb panels along the longitudinal axis of the first skin to form a honeycomb core having an outer perimeter within the periphery of the first skin; positioning a second skin onto the honeycomb core, the second skin having an outer perimeter within the periphery of the first skin; and curing an adhesive to create a bond between the first skin, the honeycomb core, and the second skin to form a composite skin.

Abstract: In some embodiment, an aircraft includes a flying frame having an airframe, a distributed propulsion system attached to the airframe, the distributed propulsion system including a plurality of propulsion assemblies and a flight control system operably associated with the distributed propulsion system. The flying frame has a vertical takeoff and landing mode and a forward flight mode. The flight control system is operable to independently control the propulsion assemblies. The flight control system is also operable to detect faults in individual propulsion assemblies and to perform corrective action responsive to detected faults at a distributed propulsion system level.

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: In some embodiments, an aircraft includes a flying frame having an airframe, a propulsion system attached to the airframe and a flight control system operably associated with the propulsion system wherein, the flying frame has a vertical takeoff and landing mode and a forward flight mode. A pod assembly is selectively attachable to the flying frame such that the flying frame is rotatable about the pod assembly wherein, the pod assembly remains in a generally horizontal attitude during vertical takeoff and landing, forward flight and transitions therebetween.