Abstract: A method for an aircraft is provided in one example embodiment and may include determining a transition from an airplane mode to a helicopter mode for a propulsion system of the aircraft, wherein the propulsion system comprises a plurality of rotor blades; determining whether a descent rate condition is satisfied, wherein the descent rate condition is associated with a maximum allowable descent rate for the aircraft; and controlling a collective pitch angle for the plurality of rotor blades based on the descent rate condition.

Abstract: A method of cutting a wafer of composite core from a bulk composite core including the steps of placing the bulk composite core in a container, the bulk composite core having a plurality of tube members; depositing a potting compound in contact with an outer surface of the bulk composite core; curing the potting compound; and after curing of the potting compound, cutting through each of the tube members. A method of cutting a wafer of composite core from a bulk composite core, the method comprising the steps of stabilizing the bulk composite core by wrapping an exterior of the bulk composite core with a composite wrap, the bulk composite core having a plurality of tube members; curing the composite wrap; and cutting through each of the tube members.

Abstract: An inboard beam includes a body having an upper flange and a lower flange coupled thereto. The upper flange includes a first upper inboard aperture and an upper outboard aperture formed therein. The lower flange includes a first lower inboard aperture and a lower outboard aperture formed therein. An upper beam fitting is coupled to the upper flange and lower beam fitting is coupled to the lower flange. The upper beam fitting includes a first upper inboard post. The upper beam fitting includes an upper outboard post extending parallel to the inboard post. The lower beam fitting includes a first lower inboard post. The lower beam fitting includes a lower outboard post extending parallel to the lower inboard post.

Abstract: In one embodiment, an apparatus comprises a particle damper for damping a component when the particle damper is attached to the component. The particle damper comprises a plurality of pockets configured to hold a plurality of particles, and the particle damper also comprises an attachment fitting for coupling the particle damper to the component.

Abstract: In one embodiment, a centrifugal force generating device comprises a first hydraulic rotor, a second hydraulic rotor, and one or more hydraulic control valves. The first hydraulic rotor comprises a first mass and is configured to rotationally drive the first mass around a first axis of rotation using a first flow of hydraulic fluid through the first hydraulic rotor. The second hydraulic rotor comprises a second mass and is configured to rotationally drive the second mass around a second axis of rotation using a second flow of hydraulic fluid through the second hydraulic rotor. The one or more hydraulic control valves are configured to control the first flow of hydraulic fluid through the first hydraulic rotor and the second flow of hydraulic fluid through the second hydraulic rotor.

Abstract: In one embodiment, a split torque gearbox can include a first compound gear and a second compound gear. The compound gears can each include a piston housing with a fluid inlet and a piston received in the piston housing and defining a space within the first piston housing exposed to the fluid inlet. The split torque gearbox can include a fluid line coupled to each of the fluid inlets to supply a fluid to the pistons at a predetermined pressure, the fluid line coupled to the second fluid inlet to supply fluid to the second piston assembly at the predetermined pressure. Pressure developed in the pistons is equal for all gear shafts, and can equalize torque imbalances in the split torque gearbox.

Abstract: A fly-by-wire system for a rotorcraft includes a computing device having control laws. The control laws are operable to engage a roll command or a yaw command in response to deflection of a beep switch of a pilot control assembly, wherein a roll angle for the roll command or a yaw rate for the yaw command is determined based on forward airspeed of the rotorcraft. The beep switch may be disposed on a collective control of the pilot control assembly. The control laws are further operable to disengage the roll command or the yaw command in response to the beep switch being returned from a deflected position to a neutral position. In representative aspects, the roll angle or the yaw rate may correspond to a standard rate turn (e.g., 3° per second).

Abstract: A rotary propulsion system for a tiltrotor aircraft operable to transition between rotary and non rotary flight modes. The rotary propulsion system includes an engine that is coupled to a freewheeling unit. A gear system has a torque path coupling assembly between a first gear assembly that is coupled to the freewheeling unit and a second gear assembly that is coupled to a proprotor assembly. The torque path coupling assembly has an engaged position wherein the output of the first gear assembly is coupled to the input of the second gear assembly thereby providing a torque path between the engine and the proprotor assembly. The torque path coupling assembly also has a disengaged position wherein the output of the first gear assembly is independent of the input of the second gear assembly thereby interrupting the torque path between the engine and the proprotor assembly.

Abstract: A bidirectional aircraft rotor for a rotorcraft tail rotor. The rotorcraft tail rotor uses a hub and a first tail rotor blade affixed to the hub. A pitch of the first tail rotor blade is fixed, and a profile of a leading edge of the first tail rotor blade is identical to a profile of a trailing edge of the first tail rotor blade. The tail rotor is driven by a torque source, such as an electric motor or an engine. The tail rotor uses variable RPM and reversible rotational direction to provide rotorcraft with yaw control.

Abstract: A series of heated control sticks for rotorcrafts, tiltrotors, and helicopters. The heated collective and cyclic sticks feature several heater assemblies to provide localized heating for pilots and co-pilots. The heater assemblies are formed from several layers of fabrics and resistive materials designed to generate heat while current is provided to conductive materials in the resistive material. A controller provides individualized control for users to adjust the temperature of various zones associated with either the collective stick or the cyclic stick. The heater assemblies can be installed entirely external to the stick like in a retrofit or partially internally.

Abstract: According to one embodiment, a clutch may be coupled between a rotor system and a power train of a rotorcraft. The clutch may be operable to disengage the rotor system from the power train during operation of the power train. A clutch control system in communication with the clutch and include a rotorcraft condition sensor operable to sense an operating condition of the rotorcraft and a control unit operable to prevent the clutch from disengaging the rotor system from the power train if the operating condition of the rotorcraft fails to satisfy a predetermined criterion.

Abstract: A method of determining a center of gravity of an aircraft in flight by comparing actual control surface actuator displacements to expected control surface actuator displacements. And a method of fuel/load management based on an offset of the center of gravity from a preferred center of gravity and a handling qualities factor.

Abstract: An aircraft is described and includes an airframe including first and second wings each having first and second oppositely disposed wing tips; first and second booms respectively extending longitudinally between the first and second wings and having forward and aft ends; first and second tail assemblies respectively coupled to aft ends of the first and second booms; first and second forward propulsion assemblies respectively coupled to the forward ends of the first and second booms, wherein the first and second forward propulsion assemblies are tiltable between a vertical takeoff and landing (“VTOL”) flight mode orientation and a forward flight mode orientation; first and second aft propulsion assemblies respectively coupled to upper ends of the tail assemblies, wherein the first and second aft propulsion assemblies are tiltable between a VTOL flight mode orientation and a forward flight mode orientation; and a payload module removably coupled to the airframe.

Abstract: A method and system to measure a parameter associated with a component, device, or system with a specified accuracy, including: providing one or more sensors operably disposed to detect the parameter; obtaining a coarse measurement of the parameter within a first range using the one or more sensors, wherein the first range includes minimum and maximum values for the parameter; obtaining a fine measurement of the parameter within a second range using the one or more sensors, wherein the second range is smaller than the first range and has a specified ratio to the first range that provides the specified accuracy; determining a current value of the parameter by combining the coarse and fine measurements; and providing the current value of the parameter to a communications interface, a storage device, a display, a control panel, a processor, a programmable logic controller, or an external device.

Abstract: A rotor blade assembly for a tiltrotor aircraft comprising a rotor blade pivotally connected to a yoke with dual concentric blade bolts having a common central axis providing a pivotal axis inboard of an outboard CF bearing and the yoke tip. In use, the compact folded arrangement of the rotor blades reduces folded aircraft dimensions in response to ever increasing restricted storage space parameters.

Abstract: A modular refueling system for an aircraft includes a modular bay recessed within the aircraft. The modular bay includes a modular bay interface. The modular refueling system includes a plurality of payload modules each having a respective function and a payload interface adapted to connect to at least a portion of the modular bay interface. The plurality of payload modules includes an aerial refueling module. The payload modules are interchangeably insertable into the modular bay to enable the modular bay to support the functions of the payload modules. The aerial refueling module is insertable into the modular bay to enable the aircraft to provide fuel to recipient aircraft during flight.

Abstract: A method, system, and device for diagnosing an anomaly of a monitored component in a drive train, the method including obtaining original data based on samples of a vibration signal; converting the original data to an analytical signal having a real component and an imaginary component; determining complex magnitudes of the analytical signal; processing the complex magnitudes of the analytical signal to produce a frequency-domain signal; and determining complex magnitudes of the frequency-domain signal to generate a shock spectrum.

Abstract: A method of manufacturing a tiltrotor wing structure including providing a spar mold having a plurality of bores extending from an exterior surface of the mold to an interior surface of the mold, the plurality of bores corresponding to a plurality of primary coordination holes in a spar member, the spar mold having a periphery defined by a top edge, a bottom edge and outboard ends; selecting a plurality of resin impregnated plies to ensure that the plies continuously extend beyond the periphery of the spar mold; laying the plies in the spar mold; curing the plies in the mold to form a cured spar member that extends beyond the periphery of the spar mold; and accurately drilling a plurality of primary coordination holes in the cured spar member in the spar mold using a tool positioned in the plurality of bores.

Abstract: According to one embodiment, an aircraft component is manufactured from a plurality of separate materials comprising a first material. The first material is physically associated with a tracking device comprising a first storage medium featuring line-of-sight accessible information and a second storage medium featuring non-line-of-sight accessible information. The line-of-sight accessible information and the non-line-of-sight accessible information each comprise information regarding the first material physically associated with the tracking device.

Abstract: An anti-tail buffet device leverages existing rotorcraft components to attenuate a tailboom's lateral “ringing” from air buffeting. Anti-buffet masses are tuned to the tailboom's lateral-bending or torsional natural frequency such that when lateral motion occurs, the response at this frequency is cancelled by the anti-buffet system, preventing this vibration from entering into the tailboom structure. Motion stops prevent over-travel. The mass of the tail rotor actuator is soft-mounted, such that its natural frequency is equal to the tailboom's lateral-bending or torsional natural frequency. When lateral loading occurs on the tail rotor disk, the lateral response at this frequency is attenuated by the soft-mounted tail rotor actuator, thereby preventing the vibration in the tailboom structure.