Abstract: A gearbox filler assembly includes a cylindrical insert attached to an interior of a port disposed within a housing of the gearbox. The cylindrical insert has a first end disposed within the port, a second end extending outward from the port and is configured to receive a detachable filler cap, a retaining lip around at least a portion of a first interior circumference proximate to the first end, and a retaining slot around at least a second interior circumference between the retaining lip and the second end. A retaining ring is detachably coupled within the retaining slot. A cylindrical baffle is detachably retained between the retaining ring and the retaining lip.

Abstract: A multirotor aircraft comprises at least three proprotors. Each proprotor has a plurality of rotor blades pivotably attached to a mast assembly. When a rotor blade pitch angle is changed for a proprotor, all rotor blades on the proprotor change to a same pitch angle. The proprotors are configured to spin freely when a power source is disengaged or fails. In various embodiments, one or more engines provides power to each proprotor, or at least one engine provides power to two or more proprotors. A rotor blade control system is configured to control a collective rotor blade pitch angle on each proprotor independently of the rotor blade pitch on the other proprotors. The rotor blade control system is configured to set a negative collective rotor blade pitch angle on an unpowered proprotor, such as in response to manual inputs by a pilot or in response to current engine conditions.

Abstract: Embodiments are directed to an aerodynamic spinner fairing having a sidewall and one or more airflow intakes in the sidewall. The airflow intakes are closed during a first phase of flight and open during a second phase of flight. The first phase of flight may be an airplane mode for a tiltrotor aircraft, and the second phase of flight may be a helicopter mode for the tiltrotor aircraft. The airflow intakes may comprise an opening in the sidewall, and a door that is configured to move between a first position covering the opening and a second position exposing the opening to external airflow. An actuator coupled to the door may operate to move the door between the first position and the second position. One or more guide vanes within the aerodynamic spinner fairing may be configured to direct air received via the airflow intakes to provide convection cooling.

Abstract: In one embodiment, an assembly fixture may include a base structure including a plurality of strands of a fiber-reinforced thermoplastic material comprising a thermoplastic embedded with a plurality of reinforcement fibers, wherein the plurality of reinforcement fibers is aligned within each strand of the plurality of strands, and wherein the base structure further comprises an anisotropic thermal expansion property based on an orientation of the plurality of reinforcement fibers within the base structure, The assembly fixture may further include a plurality of fastening structures coupled to the base structure, wherein the plurality of fastening structures is configured to fasten a plurality of components of a composite structure for assembly using a heated bonding process.

Abstract: A pitot-static array system for a tail-sitting aircraft has a disk with a plurality of edge ports arrayed about an edge of the disk. Each of a plurality of pressure transducers is configured to measure air pressure at one of the edge ports. The edge ports are arrayed about an axis parallel to a pitch axis of the aircraft.

Abstract: A rotorcraft rotor blade assembly includes a stub spar extending less than a full span of the rotor blade assembly. An upper skin portion extends substantially the full span of the rotor blade assembly. A lower skin portion extends substantially the full span of the rotor blade assembly. The stub spar is positioned between the upper skin portion and the lower skin portion.

Abstract: The present invention includes a span-balance pocket in a surface of a rotor blade, the span-balance pocket including an inboard surface and an outboard surface; and one or more weights disposed in the span-balance pocket to span-balance the rotor blade; and at least one of one or more retention devices to retain the one or more weights against the outboard surface of the span-balance pocket or the span-balance pocket is machined or molded into a tip block of the rotor blade.

Abstract: A duct interface system and method includes a duct having a first end and a second end; a first receptacle for the first end of the duct and/or a second receptacle for the second end of the duct; and one or more first seals between the first end of the duct and the first receptacle and/or one or more second seals between the second end of the duct and the second receptacle.

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: 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 system is provided in one example embodiment and may include a first reservoir for a lubricant; a second reservoir for the lubricant, wherein the first reservoir and the second reservoir are interconnected; a first pumping element to pump the lubricant from the first reservoir at a first flow rate; a second pumping element to pump the lubricant at a second flow rate, wherein the first flow rate and the second flow rate are different; and a gearbox coupled to the first pumping element and the second pumping element. The first reservoir may have a larger volume than the second reservoir and the first flow rate may be higher than the second flow rate.

Abstract: A vibration control system for a rotor hub provides vibration attenuation in an aircraft by reducing the magnitude of rotor induced vibratory. The system can include a force generating device attached to a rotor hub which rotates along with the rotor at the rotational speed of the rotor. Vibratory shear force is generated by rotating unbalanced weights each about an axis non-concentric with the rotor hub axis at high speed to create large centrifugal forces. The rotational speed of the weights can be a multiple of the rotor rotational speed to create shear forces for canceling rotor induced vibrations. The amplitude of the generated shear force is controlled by indexing the positions of the unbalanced weights relative to each other, while the phase of the shear force is adjusted by equally phasing each weight relative to the rotor.

Abstract: In one embodiment, a rotor blade may comprise a blade body, a spar structure, and a blade nose. The blade body may comprise a skin, wherein the skin is configured to form an airfoil shape, and wherein the airfoil shape comprises an inboard end, an outboard end, a leading edge, and a trailing edge. The spar structure may comprise a first spar cap and a second spar cap, wherein the first spar cap is coupled to an upper portion of the skin, and wherein the second spar cap is coupled to a lower portion of the skin. The blade nose may comprise a cavity, wherein the cavity is configured to house a plurality of modular weights at a plurality of radial blade locations, wherein the plurality of radial blade locations comprises a range of locations between the inboard end and the outboard end.

Abstract: A system for monitoring lubrication of a drive train, including a lubricant pressure sensor to detect a pressure of the lubricant in the drive train and to provide a lubricant pressure signal; lubricant volume sensor to detect a volume of the lubricant in the drive train and to provide a lubricant volume signal; non-contact temperature sensor to detect a temperature of the drive train and to provide a non-contact temperature signal; and logic management system in communication with the lubricant pressure sensor, the lubricant volume sensor, and the non-contact temperature sensor; the logic management system configured to receive and process the lubricant pressure signal, the lubricant volume signal, and the non-contact temperature signal; wherein when the lubricant pressure signal reaches a predetermined minimum pressure level and the lubricant volume signal reaches a predetermined minimum volume level, the logic management system displays non-contact temperature measurement data to a display device.

Abstract: A support bracket for grounding a current sensor is disclosed. The support bracket comprises a first surface and a second surface. The first surface is electrically coupled to a current sensor to provide a current path to ground the current sensor. The second surface is physically coupled to the current sensor in order to support the current sensor.

Abstract: An exemplary rotorcraft includes a propulsion system including a prime mover and a drive shaft coupled to the prime mover, the drive shaft including a coupling separating the drive shaft into an input shaft and an output shaft, the coupling operable between an engaged position rotationally coupling the input shaft and the output shaft and a disengaged position rotationally disengaging the output shaft from the input shaft, a main rotor coupled to the prime mover, a secondary rotor attached to the output shaft, and a motor coupled to the output shaft.

Abstract: Embodiments are directed to solid lubricant assemblies for providing over temperature protection for bearings and gears in rotorcraft systems. A solid lubricant enters a fluid state above a certain temperature and is positioned so that fluid lubricant is applied to the bearings or gears.

Abstract: An example of a hub for a tail rotor includes a body configured to couple to a mast of a rotor system, a trunnion disposed within the body, first and second shafts disposed on opposite sides of the trunnion, first and second end plates secured to the body, and first and second end bearings, the first end bearing disposed between the first shaft and the first end plate and the second end bearing disposed between the second shaft and the second end plate.

Abstract: The present invention includes a helicopter rotor seal assembly comprising: a rotor mast having a longitudinal axis and an outer surface; a sleeve aligned longitudinally with the axis and surrounding a portion of the rotor mast, the sleeve having an outer surface, and an inner surface; an annular horizontal seal between the inner surface of the sleeve and the outer surface of the rotor mast; and an upper annular rotor mast seal affixed to the outer surface of the rotor mast and extending outwardly sufficient to cover the annular horizontal seal.

Abstract: An example of a mounting rail system for a console of an aircraft includes a mounting rail with a track that includes two bevelled faces, a pyramidal nut configured to fit within the track, and a mounting bracket configured to be secured to the mounting rail via a fastener that attaches to the pyramidal nut. The pyramidal nut includes two bevelled faces that align with the two bevelled faces of the track.