Abstract: A chip agitation system for use on a rotorcraft with an engine and transmission system. The chip agitation system is configured to produce a mass flux of fluid to agitate chip debris towards a chip detection device. The chip agitation system includes a reservoir and valve that can be selectively opened and closed.

Abstract: A bearing restraint, for use on a rotorcraft with a rotor mast and bearing assembly. The bearing restraint interfacing with a mast groove along the rotor mast to longitudinally restrain the bearing assembly. The bearing restraint includes a pilot ring, groove collar, and retaining ring.

Abstract: A cam-locking system for use with a retractable driveshaft that includes a housing, a cam carrier located at least partially in the housing, and a cam rotatably coupled to the cam carrier. Translation of the cam carrier along a central axis allows the cam to rotate into cooperative engagement with a catch recess on an interior surface of the housing, preventing the cam carrier from translating backwards, and thereby maintaining the retractable driveshaft in an engaged position. Further advancement of the cam carrier allows that cam to rotate into and unlocking gap in the interior surface of the housing, which enables the cam carrier to translate backwards along the central axis below the locked position, thereby disengaging the retractable driveshaft.

Abstract: An embodiment of the present invention provides an aircraft that includes a fuselage and a rotatable wing disposed above the fuselage. At least one cross-wing driveshaft is disposed within the wing and is driven in rotation by a drive system connected to first and second engines that are located at respective sides of the fuselage beneath the wing. The drive system is so configured that one or both of the first engine and the second engine can drive the at least one cross-wing driveshaft in the event of failure of an engine.

Abstract: A bearing restraint, for use on a rotorcraft with a rotor mast and bearing assembly. The bearing restraint interfacing with a mast groove along the rotor mast to longitudinally restrain the bearing assembly. The bearing restraint includes a pilot ring, groove collar, and retaining ring.

Abstract: Briefly, the disclosure relates to apparatuses and methods to form a gearbox enclosure comprising an external liner, an internal liner, and a variable porosity region disposed between the external liner and the internal liner. The variable porosity region may be configured to accommodate flow of the lubricant, thereby providing a capability to cool, for example, a lubricating fluid at an elevated temperature.

Abstract: Various implementations described herein are directed to an emergency lubrication system for a tiltrotor aircraft. The emergency lubrication system includes a pressurized material chamber, a lubrication chamber, a first valve between the pressurized material chamber and the lubrication chamber, a gearbox, and a second valve between the lubrication chamber and the gearbox. The first valve is configured to operate in a first mode when the emergency lubrication system is in a first configuration and a second mode when the emergency lubrication system is in a second configuration.

Abstract: A tiltrotor aircraft includes a propulsion system with a fixed engine and a rotatable proprotor. The engine is located below the wing of the tiltrotor aircraft, and the rotatable proprotor assembly is mounted on the top surface of the wing. The engine and proprotor assembly are connected via a series of one or more gearboxes that route the engine output from the engine to the proprotor.

Abstract: Embodiments are directed to a selectable drive system that allows a rotor gearbox to send torque to a proprotor assembly and/or through a multiplier planetary gear set to a pylon-mounted ducted fan thrust unit. The rotor drive system may be a stop-fold system in which rotor blades can be folded when not rotating. This allows a normally idle lift engine to provide additional aircraft thrust during cruise where an aircraft is typically using only a dedicated thrust engine for high speed flight. An inline engage/disengage actuator or “shift fork” on the rotor gearbox is used to select the torque-output direction. The multiplier planetary gear set increases the output RPM that is received from the rotor gearbox and that is applied to the thrust fan unit.

Abstract: An embodiment of the present invention provides an aircraft that includes a fuselage and a rotatable wing disposed above the fuselage. At least one cross-wing driveshaft is disposed within the wing and is driven in rotation by a drive system connected to first and second engines that are located at respective sides of the fuselage beneath the wing. The drive system is so configured that one or both of the first engine and the second engine can drive the at least one cross-wing driveshaft in the event of failure of an engine.

Abstract: An embodiment of the present invention provides an aircraft that includes a fuselage and a rotatable wing disposed above the fuselage. At least one cross-wing driveshaft is disposed within the wing and is driven in rotation by a drive system connected to first and second engines that are located at respective sides of the fuselage beneath the wing. The drive system is so configured that one or both of the first engine and the second engine can drive the at least one cross-wing driveshaft in the event of failure of an engine.

Abstract: A cam-locking system for use with a retractable driveshaft that includes a housing, a cam carrier located at least partially the housing, and a cam rotatably coupled to the cam carrier. Translation of the cam carrier along a central axis allows the cam to rotate into cooperative engagement with a catch recess on an interior surface of the housing, preventing the cam carrier from translating backwards, and thereby maintaining the retractable driveshaft in an engaged position. Further advancement of the cam carrier allows that cam to rotate into and unlocking gap in the interior surface of the housing, which enables the cam carrier to translate backwards along the central axis below the locked position, thereby disengaging the retractable driveshaft.

Abstract: A tiltrotor aircraft includes a propulsion system with a fixed engine and a rotatable proprotor. The engine is located on the top surface of the wing of the tiltrotor aircraft, and the rotatable proprotor assembly is also mounted on the top surface of the wing. The engine and proprotor assembly are connected via a series of one or more gearboxes that route the engine output from the engine to the proprotor.

Abstract: Embodiments are directed to a selectable drive system that allows a rotor gearbox to send torque to a proprotor assembly and/or through a multiplier planetary gear set to a pylon-mounted ducted fan thrust unit. The rotor drive system may be a stop-fold system in which rotor blades can be folded when not rotating. This allows a normally idle lift engine to provide additional aircraft thrust during cruise where an aircraft is typically using only a dedicated thrust engine for high speed flight. An inline engage/disengage actuator or “shift fork” on the rotor gearbox is used to select the torque-output direction. The multiplier planetary gear set increases the output RPM that is received from the rotor gearbox and that is applied to the thrust fan unit.

Abstract: A cam-locking system for use with a retractable driveshaft that includes a housing, a cam carrier located at least partially in the housing, and a cam rotatably coupled to the cam carrier. Translation of the cam carrier along a central axis allows the cam to rotate into cooperative engagement with a catch recess on an interior surface of the housing, preventing the cam carrier from translating backwards, and thereby maintaining the retractable driveshaft in an engaged position. Further advancement of the cam carrier allows that cam to rotate into and unlocking gap in the interior surface of the housing, which enables the cam carrier to translate backwards along the central axis below the locked position, thereby disengaging the retractable driveshaft.

Abstract: A driveshaft includes a first end, a second end, and a length extending from the first end to the second end. The driveshaft includes an engagement section at the first end configured to cooperatively engage and transfer torque to a gearbox. The driveshaft also includes a compressible section configured to selectively decrease the length of the driveshaft. The driveshaft being configured to transition between an engaged configuration, wherein the engagement portion is engaged with the gearbox, and a disengaged configuration, wherein the compressible section is compressed, and the engagement portion is disengaged from the apparatus.

Abstract: Embodiments are directed to a rotor mast for an aircraft comprising a shaft portion, a carrier portion having a plate and a web, and frame segments that separate the web from the plate at a fixed distance. The shaft portion, the plate, the web, and the frame segments are as single component. A plurality of first holes are formed in the plate, and a plurality of second holes are formed in the web. Pairs of the first and second holes are aligned. Posts are mounted between each pair of first and second holes. Pinion gears are mounted on the posts. Roller bearings are mounted between the posts and pinion gears. An open region of the web is configured to allow a sun gear to mesh with the pinion gears.

Abstract: A rotorcraft includes a fuselage with at least one rotor assembly coupled thereto. A drivetrain provides rotational energy to the rotor assembly. The drivetrain includes an engine and a gearbox having a gearbox housing. A gearbox cooling fin array including a plurality of cooling fins is bonded to the gearbox housing with a thermal interface material. The gearbox cooling fin array is configured to dissipate heat generated by the gearbox during operation of the rotorcraft.

Abstract: Systems and methods include providing an aircraft with a fuselage and a wing assembly rotatable relative to the fuselage about a stow axis between a flight position and a stowed position. The aircraft includes a drive component having a retractable driveshaft that selectively engages the mid-wing gearbox via axially translatable motion along a rotation axis when the wing assembly is in the flight position. The mid-wing gearbox is misaligned with the retractable driveshaft when the wing assembly is in the stowed position. A seal is coupled to the drive component at a first end and the mid-wing gearbox at a second end and deploys in order to maintain a sealed connection between the drive component and the mid-wing gearbox when the wing assembly is transitioned between the flight position and the stowed position.

Abstract: A dynamic rotor-phasing unit can phase rotors in-flight for dynamic rotor tuning and in an idle state for aircraft storage. The input and output shafts can be clocked (e.g., rotated) from 0 degrees apart to in excess of 360 degrees apart or from 0 degrees apart to 140 degrees apart. Such rotation can minimize the footprint of an aircraft for stowing purposes, as the rotor blades can be folded to fit within a smaller area without disconnecting the drive system. Additionally, the unit can allow tiltrotor blades to be clocked during flight, which can allow the live-tuning of the aircraft's rotor dynamics. A fail-safe rotary actuator can rotate a stationary planet carrier to clock the input shaft and the output shaft. Alternatively, an actuator can position a slider housing to clock the input shaft and the output shaft.