Abstract: A method of determining damage tolerance allowables in a specimen, the method includes applying a cyclic load to a specimen until a first crack emanates from a notch in the specimen, the cyclic load having a maximum load and a minimum load. The method also includes applying a subsequent cyclic load to the specimen until the first crack grows to form a second crack emanating from the first crack, the subsequent cyclic load having the same maximum load but a greater minimum load.

Abstract: In accordance with an embodiment of the present invention, a method of operating a rotorcraft includes operating the rotorcraft in a heading control mode that includes activating a yaw channel path of a heading controller and deactivating a roll channel path of the heading controller when a speed of the rotorcraft is less than a first speed threshold or a heading error is less than a heading error threshold, and activating the roll channel path of the heading controller and deactivating the yaw channel path of the heading controller when the speed of the rotorcraft is greater than a second speed threshold and the heading error is not less than the heading error threshold.

Abstract: A helicopter has a fuselage, a main rotor system connected to the fuselage and configured to rotate in a rotor direction, the main rotor system comprising a retreating rotor blade side and an opposing advancing rotor blade side, and a first wing extending from the fuselage on the retreating rotor blade side. The helicopter comprises no tail rotor system and comprises no counter-rotating rotor system coaxial with the main rotor system.

Abstract: In some embodiments, a pod assembly transportation system includes a transportation services provider computing system and a plurality of flying frame flight control systems, wherein the system is configured to receive, at the transportation services provider computing system, a request for transportation of a pod assembly; upload a flight plan to a flight control system of a flying frame including an airframe and a distributed propulsion system coupled to airframe; dispatch the flying frame by air to the current location of the pod assembly; couple the pod assembly to the flying frame; transport the pod assembly by air from the current location of the pod assembly to the destination of the pod assembly including transitioning the flying frame between a vertical takeoff and landing mode and a forward flight mode; and decouple the pod assembly from the flying frame at the destination of the pod assembly.

Abstract: A tiltrotor aircraft having a VTOL flight mode, a forward flight mode and a storage mode includes a fuselage having a wing rotatably mounted thereto. The wing has an orientation generally perpendicular to the fuselage, in the flight modes, and an orientation generally parallel to the fuselage, in the storage mode. First and second pylon assemblies are positioned proximate outboard ends of the wing. First and second mast assemblies are respectively rotatable relative to the first and second pylon assemblies and have generally vertical orientations, in the VTOL flight mode, and generally horizontal orientations, in the forward flight mode and the storage mode. First and second proprotor assemblies are respectively rotatable relative to the first and second mast assemblies. Each proprotor assembly includes a plurality of rotor blades and has a radially extended orientation, in the flight modes, and a stowed orientation, in the storage mode.

Abstract: A hub system comprises at least one yoke, at least one shear bearing, and at least one mast adapter. The at least one mast adapter is configured to support the at least one yoke and the at least one shear bearing, and the at least one yoke has a flapping hinge that is non-coincident with a flapping hinge of the at least one shear bearing. Another hub system comprises a stacked yoke and a mast adapter. The mast adapter is configured to transfer rotation from a rotor mast to the hub system to rotate the hub system about a central axis of rotation. The mast adapter is further configured to support the stacked yoke such that each yoke in the stacked yoke is configured to accommodate at least some amount of rotation about an axis that is perpendicular to or about perpendicular to the central axis of rotation.

Abstract: A hydraulic system for an aircraft having an engine and an auxiliary power unit includes a first hydraulic subsystem including a first hydraulic pump and a first set of hydraulic-powered components in fluid communication with the first hydraulic pump. The first hydraulic pump is powered by the engine to pump shared hydraulic fluid to the first set of hydraulic-powered components. The hydraulic system includes a second hydraulic subsystem including a second hydraulic pump and a second set of hydraulic-powered components in fluid communication with the second hydraulic pump. The second hydraulic pump is powered by the auxiliary power unit to pump the shared hydraulic fluid to the second set of hydraulic-powered components. A shared return line subsystem and reservoir is in fluid communication with the first and second hydraulic subsystems to return the shared hydraulic fluid to the first and second hydraulic pumps.

Abstract: A pylon assembly for a tiltrotor aircraft includes a fixed pylon having an outboard end. A rotor assembly is rotatably coupled to the fixed pylon and is operable to rotate between a a vertical takeoff and landing orientation and a forward flight orientation. The rotor assembly includes a proprotor operable to produce a slipstream. A wing extension is rotatably coupled to the outboard end of the fixed pylon. The wing extension is operable to rotate generally with the rotor assembly such that a minimal dimension of the wing extension remains in the slipstream of the proprotor.

Abstract: A high stiffness hub assembly for a proprotor system operable to rotate with a mast of a tiltrotor aircraft having helicopter and airplane flight modes. The hub assembly includes a yoke and a constant velocity joint assembly. The yoke has four blade arms each adapted to hold a proprotor blade. The constant velocity joint assembly provides a torque path from the mast to the yoke that includes a trunnion assembly, four drive links and four pillow blocks. The trunnion assembly is coupled to the mast and has four outwardly extending trunnions. Each drive link has a leading bearing coupled to one of the trunnions and a trailing bearing coupled to one of the pillow blocks. Each pillow block is independently mounted between an upper surface of the yoke and a hub plate with two connection members that extend through the yoke and the pillow block.

Abstract: There is a method of making a tubular specimen with a predetermined wrinkle defect including providing a layup tool with a cavity forming member having a cavity which resembles a desired shape of the at least one wrinkle; orienting a composite material around the mandrel at a wrap angle to form a closed loop; positioning a wrinkle tool on the closed loop; and/or generating at least one wrinkle with a predetermined characteristic in a portion of the closed loop to form a tubular specimen. The predetermined characteristic is at least one of the following: wrinkle location, an outward wrinkle, an inward wrinkle, a wrinkle width, a wrinkle height, and a wrinkle length. In another aspect, there is a method of offset load testing a tubular composite specimen. In a third aspect, there is a method of determining allowable defects for a composite component.

Abstract: In a first aspect, there is a method of making a specimen with a predetermined wrinkle defect, the steps including orienting a composite material around a layup tool at a wrap angle to form a closed loop; and generating at least one wrinkle with a predetermined characteristic in a portion of the closed loop to form a specimen. The predetermined characteristic is at least one of the following: wrinkle location, an outward wrinkle, an inward wrinkle, a wrinkle width, a wrinkle height, and a wrinkle length. In another aspect, there is a method of determining allowable defects for a composite component.

Abstract: A vibration isolation system for an advancing blade concept rotorcraft having a pylon assembly and an airframe. The vibration isolation system includes one or more pylon links each having first and second ends with the first end coupled to the pylon assembly and the second end coupled to the airframe. Each pylon link includes a vibration isolator, such as a Liquid Inertia Vibration Eliminator unit, that is interposed between the pylon assembly and the airframe. The vibration isolator system is operable to reduce or eliminate transmission of the pylon assembly vibration to the airframe.

Abstract: A tiltrotor aircraft having a VTOL flight mode, a forward flight mode and a storage mode includes a fuselage having a wing rotatably mounted thereto. The wing has an orientation generally perpendicular to the fuselage, in the flight modes, and an orientation generally parallel to the fuselage, in the storage mode. First and second pylon assemblies are positioned proximate outboard ends of the wing. First and second mast assemblies are respectively rotatable relative to the first and second pylon assemblies and have generally vertical orientations, in the VTOL flight mode, and generally horizontal orientations, in the forward flight mode and the storage mode. First and second proprotor assemblies are respectively rotatable relative to the first and second mast assemblies. Each proprotor assembly includes a plurality of rotor blades and has a radially extended orientation, in the flight modes, and a stowed orientation, in the storage mode.

Abstract: Embodiments refer generally to systems and methods for providing autorotative enhancement for helicopters using an autorotative assist unit coupled to the transmission of the helicopter. Methods of utilizing an autorotative assist unit as well as retrofitting an autorotative assist unit to an existing helicopter are also disclosed. By employing an autorotative assist unit, improved autorotation can be achieved without the need to increase the weight of the rotor.

Abstract: An aircraft has an airframe with a distributed thrust array attached thereto that includes a plurality of propulsion assemblies each of which is independently controlled by a flight control system. Each propulsion assembly includes a housing with a gimbal coupled thereto and operable to tilt about a single axis. A propulsion system is coupled to and operable to tilt with the gimbal. The propulsion system includes an electric motor having an output drive and a rotor assembly having a plurality of rotor blades that rotate in a rotational plane to generate thrust having a thrust vector with a magnitude in the longitudinal direction. Actuation of each gimbal is operable to tilt the respective propulsion system relative to the airframe in the longitudinal direction to change the rotational plane of the respective rotor assembly relative to the airframe, thereby controlling the magnitude of the respective thrust vector in the longitudinal direction.

Abstract: A helicopter has a mast axis and a rotorcraft blade assembly. The rotorcraft blade assembly has a main body and a blade tip movable relative to the main body. The rotorcraft blade assembly is selectively rotatable about the mast axis.

Abstract: An aircraft including a nacelle disposed at a fixed location relative a wing member; a proprotor housing coupled to the nacelle, the proprotor housing configured to selectively rotate between a horizontal orientation and a non-horizontal orientation; a door pivotably coupled to the proprotor housing; and a linkage to connect the door and the nacelle, the linkage configured to move with the door from a closed position when the proprotor housing is in a horizontal orientation to an open position when the proprotor housing is in a non-horizontal orientation. In some embodiments, there can be a hinge member for hingedly coupling the door to the proprotor and/or nacelle. In other embodiments, the door includes a flexure portion. In some embodiments, the nacelle includes a plurality of doors. In other embodiments, proprotor includes a forward portion and a stationary aft portion; wherein the forward portion is configured to selectively pivot.

Abstract: The present invention achieves technical advantages as a pilot and passenger seating. An aircraft employs a pilot seat, comprising a contoured structure having ergonomically formed and padded surfaces, with left and right arm supports that include an articulated control knob, movable in three rectangular axes and rotatable about a vertical axis to provide one or more aircraft steering functions for an aircraft, and a touch-sensitive control surface for controlling one or more power system components. A passenger seat, having a contoured structure, having ergonomically formed and padded surfaces, a headrest, a seat, a left support member, and a right support member are adapted to cradle a portion of a passenger's body to support the passenger during travel.

Abstract: A door roller mechanism for cooperation with a roller track including a carriage member having a door attachment feature; at least one roller disposed for rotation on a first side of the carriage member when the carriage member moves in the rolling direction; at least one roller disposed for rotation on an opposite second side of the carriage member when the carriage member moves in the rolling direction; a first rub member disposed on the first side of the carriage; a second rub member disposed on the second side of the carriage; and at least one biasing element disposed on the carriage member for resiliently biasing the first rub member and the second rub member in opposite lateral directions so as to contact a respective first track surface and a second track surface in a manner to dampen lateral vibration of a door connected to the roller mechanism.

Abstract: The present invention achieves technical advantages as 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. The present invention includes 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.