Abstract: A hydraulic energy retention system includes a body with a piston separating a hydraulic fluid from a pressurized gas, a discharge port in fluid communication with the hydraulic fluid, and a stop operable to an engaged position to block movement of the piston past the stop and toward the discharge port. The hydraulic energy retention system may be implemented with a hydraulic fluid reservoir, such as a bootstrap reservoir.

Abstract: One embodiment is an aircraft including a fuselage; a wing connected to the fuselage; first and second booms connected to the wing on opposite sides of the fuselage; first and second forward propulsion systems attached to forward ends of the first and second booms; first and second aft propulsion systems fixedly attached proximate aft ends of the first and second booms; first and second wing-mounted propulsion systems connected to outboard ends of wings; and first and second wing tips fixedly connected to outboard sides of the first and second wing-mounted propulsion systems; wherein the first and second wing-mounted propulsion systems and the first and second wing tips are collectively tiltable between a first position when the aircraft is in a hover mode and a second position when the aircraft is in a cruise mode.

Abstract: An anti-aircraft system is described and includes an unmanned aerial vehicle (UAV) comprising a body; a wing connected to the body; and propulsion systems associated with the wing, wherein the propulsion systems comprise pylons releasably connected to opposite ends of the wing such that the propulsion systems may be selectively released from the wing during flight of the UAV.

Abstract: Disclosed is a blade lock assembly, which may include a drag brace coupled to a fold crank assembly and to a rotary wing blade and may further include an actuator assembly configured to be coupled to a rotary wing cuff. The actuator assembly may include an actuator pin housing, an actuation pin at least partially sheathed by the actuator pin housing, and an actuator configured to extend and retract the actuation pin away from and toward the actuator pin housing.

Abstract: An aircraft having an augmented reality flight control system integrated with and operable from the pilot seat and an associated pilot headgear unit, wherein the flight control system is supplemented by flight-assisting artificial intelligence and geo-location systems. Embodiments include an augmented reality flight control system incorporating real-world objects with virtual elements to provide relevant data to a pilot during aircraft flight. A translucent substrate is disposed in the pilot's field of view such that the pilot can see therethrough, and observe virtual elements displayed on the substrate. The system includes a headgear that is worn by the pilot. A flight assistance module is configured to receive data related to the aircraft and provide predictive assistance to the pilot during flight based on the received data based in part on a pilot profile having preferences related to the pilot.

Abstract: In some examples, an aircraft gearbox comprises a plurality of gears and a hybrid lubrication system to lubricate the plurality of gears. The plurality of gears comprises a first gear and a second gear. The plurality of gears operable to rotate based on torque received from a driveshaft. The hybrid lubrication system comprises a pressurized lubrication system and a non-pressurized lubrication system. The pressurized lubrication system comprises a nozzle to spray a lubricant onto the first gear. The non-pressurized lubrication system comprises a reservoir to catch a portion of the lubricant from the pressurized lubrication system. The second gear is operable to disperse the lubricant across others of the plurality of gears based on the second gear rotating through the portion of the lubricant.

Abstract: A directional tail thrust system for a helicopter includes a tailboom defining an internal air passage. The aft portion of the internal air passage includes an aft diffuser. The directional tail thrust system also includes a fan in fluid communication with the aft diffuser and a vane array including vanes coupled to the aft diffuser and configured to receive air from the fan via the aft diffuser. The vanes are pivotable to switch the vane array between various modes including an anti-torque mode to produce anti-torque thrust, a forward thrust mode to produce forward thrust and a pro-torque mode to produce pro-torque thrust.

Abstract: An improved compound planetary gear system. In embodiments, a compound planetary gear system includes at least one planet pinion including a main shaft having a first gear for meshing with a sun gear and a second gear for meshing with a ring gear, and a carrier for supporting the at least one planet pinion. Teeth of the first gear are configured with a first helical angle with respect to a longitudinal angle of the at least one planet pinion, teeth of the second gear are configured with a second helical angle with respect to the longitudinal angle of the at least one planet pinion, the first helical angle different from the second helical angle.

Abstract: In certain embodiments, a method includes forming a battery electrode on a substrate. Forming the battery electrode on the substrate includes depositing a first electrode active material layer on a first portion of a surface of the substrate and depositing, to form a current collector, a conductive material using a thin film deposition process on a surface of the first electrode active material layer. The conductive material is deposited over an edge of the first electrode active material layer and onto a second portion of the surface of the substrate, the second portion of the substrate being adjacent to the first portion of the substrate. The method includes removing the battery electrode from the substrate, the battery electrode including the first electrode active material layer and the current collector.

Abstract: According to one implementation of the present disclosure, a rotorcraft includes a fuselage, an airframe, a main rotor, first and second wings, and a wing rotation system. The wing rotation system may be coupled to the first and the second wings and includes a first drive shaft, a second drive shaft, and a uniform actuator. The first drive shaft may be coupled to the first wing for rotation around a central wing axis, the second drive shaft may be coupled to the second wing for rotation around the central wing axis, and the uniform actuator may be coupled between the first drive shaft and the airframe. Also, the wing rotation system can be configured to actuate rotation of the first and the second wings from a first direction to a second direction.

Abstract: A flight control arrangement for a hybrid aircraft includes a fixed-wing flight (F/W) control module and vertical takeoff/landing flight (VTOL) control module. The F/W control module is an integrated component having a respective network interface connected to an aircraft data network via which it provides fixed-wing control output to network-connected fixed-wing flight components including one or more horizontal-thrust components. The VTOL control module is also an integrated component having a respective network interface to the aircraft data network via which the VTOL control module (1) observes flight status as reflected in network messages originated by the fixed-wing flight control module, and (2) based on the observed flight status, generates VTOL control output to network-connected VTOL flight components including one or more vertical-thrust components, to control VTOL flight as well as transitions to and from fixed-wing flight.

Abstract: A rotor-hub flap-measurement system includes a rotor hub operable to flap relative to a main-rotor axis, a flap-linkage arm, a first end of the flap-linkage arm rotatably coupled to the rotor hub, the flap-linkage arm responsive to flapping of the rotor hub, and a magneto-resistive sensor system rotatably coupled to a second end of the flap-linkage arm and responsive to movement of the flap-linkage arm.

Abstract: In an embodiment, a battery connector includes: power terminals configured to be coupled to a load having an input capacitance; power pins electrically coupled to the power terminals; a charge pin, the charge pin being longer than each of the power pins; and an antispark circuit electrically interposed between the charge pin and the power terminals, the antispark circuit including: a dissipation circuit configured to charge the input capacitance of the load in response to a battery being coupled to the charge pin; and a delay circuit configured to delay charging of the input capacitance of the load for a predetermined duration after the battery is coupled to the charge pin.

Abstract: An aircraft is described and includes an aircraft body, a gearbox housing containing a lubricant, and a remote gearbox lubricant level gauging (RGLLG) system including a light source that when activated illuminates an interior of the gearbox housing; at least one light tube for transmitting light from inside the gearbox housing to an observer end of the RGLLG system, and at least one indicator at the observer end of for indicating a level of the lubricant contained within the gearbox based on the light transmitted via the at least one light tube.

Abstract: A system for providing ephemeral keys for a cryptographic system includes a secure enclave configured to generate one or more ephemeral keys (EKs), where each EK of the one or more EKs has a lifetime associated with the respective EK, and one or more secured devices connected to the secure enclave, where each secured device of the one or more secured devices has a trusted platform module (TPM) configured to acquire at least one of the one or more EKs, where the TPM of each secured device further is configured to generate secured data in response to validating the lifetime of an associated EK by encrypting sensitive data with the associated EK, and where each secured device of the one or more secured devices is further configured to transmit the secured data to an entity external to the secured device.

Abstract: Systems and techniques for controlling a power distribution of a hybrid powertrain system using magnetorheological (MR) clutches. In embodiments, MR clutches may be used to control the power transfer from a mechanical power source to a plurality of loads. For example, mechanical power produced by a mechanical power source (e.g., an internal combustion engine (ICE)) may be transferred to each load of the plurality of loads using an MR clutch respectively connected to each load. In this example, the amount of mechanical power transferred from the mechanical power source to each of the loads of the plurality of loads may be controlled and/or managed using the MR clutch connected to each respective load. In embodiments, a load may be engaged or disengaged from the mechanical power source gradually, such as by ramping up or ramping down the amount of mechanical power transferred via the MR clutch to the load.

Abstract: A composite shaft has a fiber orientation that is a combination of fibers perpendicular to each other and a longitudinal axis of the shaft; and a second composite layer disposed at an angle ranging between 25 to 45 degrees+/?3 degrees from the fibers in the first composite layer; a third composite layer disposed at an angle ranging between 7 to 13 degrees+/?3 degrees from the fibers in the second composite layer and each subsequent transition layer(s); a fourth composite layer disposed at an angle ranging between 25 to 45 degrees+/?3 degrees from the fibers in the third composite layer(s); and a fifth composite generally perpendicular +/?3 degrees to each other and the fibers in the fourth composite layer.