Abstract: A method of increasing a stability speed of a tiltrotor aircraft includes pivoting a rotor assembly having at least three rotor blades from a first position for operating the tiltrotor aircraft in a helicopter mode to a second position for operating the tiltrotor aircraft in an airplane mode, and increasing a stiffness of the rotor assembly when the rotor assembly is in the second position.

Abstract: An apparatus includes a shared cooling device for cooling one or more systems or components, and a plurality of primary cooling pathways. Each of the primary cooling pathways includes a fan, and each fan is in fluid communication with the shared cooling device.

Abstract: A variable-speed gearbox for a tiltrotor with fixed engine and rotating proprotor includes an input shaft coupled to the respective fixed engine, an output shaft coupled to the respective proprotor; a high-speed clutch integrated into a high-speed gear train, the high-speed gear train having an input coupled to the input shaft and an output coupled to the output shaft; and a low-speed clutch integrated into a low-speed gear train, the low-speed gear train having an input coupled to the input shaft and an output coupled to the output shaft. The high-speed clutch and the low-speed clutch can be freewheeling clutches capable of disconnecting the output and the input of the respective gear train of the high and low-speed gear trains in an overrunning condition when the output rotates faster than the input of the respective gear train. The low-speed clutch can be permanently engaged. In accordance to some embodiments the variable-speed gearboxes may include an accessory drive.

Abstract: A removable oil filter system includes an oil filter mount, an oil filter element removably connected to the oil filter mount, an impending-bypass indicator connected to the oil filter mount and in fluid communication with an oil in the oil filter system, and a full-bypass indicator in fluid communication with the oil filter mount. The impending-bypass indicator is capable of reporting an impending-bypass condition of the oil filter system. The full-bypass indicator is capable of reporting a full-bypass condition of the oil filter system.

Abstract: There is provided a rotorcraft, including a body, including a front portion and a tail portion; a main rotor system coupled to the front portion of the body, the main rotor system operable to provide a lifting force on the body; and an anti-torque system coupled to the tail portion of the body, the anti-torque system including a primary tail rotor system and a secondary tail rotor system; wherein the primary tail rotor system and the secondary tail rotor system are operable to provide a first anti-torque force and a second anti-torque force. In other aspects, there are methods of providing anti-torque force in a rotorcraft.

Abstract: A folding rotor blade assembly includes a blade fold support and a blade-fold actuator system coupled to the blade fold support. The blade-fold actuator system includes a motor, a tab configured to selectively prevent rotation of a blade tang of a rotor blade, and a cam connected to the blade fold support and coupled to the motor, the cam configured to move the tab between a locked position that prevents rotation of the blade tang and an unlocked position that permits rotation of the blade tang.

Abstract: In one embodiment, an apparatus may comprise an attachment device configured to be embedded in a structure, wherein the attachment device comprises: a body comprising a first flange and a second flange, wherein the body is configured such that the first flange and the second flange are coupled together internally within the body when the attachment device is embedded in the structure; an attachment fitting for coupling a component to the structure in which the attachment device is embedded.

Abstract: An aircraft having an electric motor coupled to a rotor and an instrument electronically connected to the electric motor and configured to communicate a time available value before a motor condition reaches a motor condition limit.

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.

Abstract: In one embodiment, a method is performed by a control computer. The method includes receiving a time series of control inputs in relation to a control axis of an aircraft, where the control computer causes actuation in response to each control input in the time series as the control input is received. The method also includes determining aircraft oscillation over a sample period corresponding to the time series. The method also includes evaluating information related to the determined aircraft oscillation using engagement settings associated with a control filter. The method also includes engaging the control filter responsive to the information satisfying the engagement settings, where the engaged control filter systematically attenuates future control inputs in relation to the control axis prior to actuation responsive thereto.

Abstract: A cooling apparatus includes a shared cooling device for one or more systems or components, and a plurality of primary cooling pathways. Each of the primary cooling pathways includes a transition duct and a fan. The transition duct is in fluid communication with the shared cooling device. The fan is in fluid communication with the transition duct.

Abstract: A method and system to isolate vibrations, including a first pair of fluid chambers disposed to isolate first vibrations between a first body and a second body, wherein the first vibrations are parallel to a first axis, wherein the first body is a propeller hub, a rotor hub, a pylon attachment, or an engine, and wherein the second body is a propeller shaft, a rotor mast, or a body attachment; a second pair of fluid chambers disposed to isolate second vibrations between the first and second bodies, wherein the second vibrations are parallel to a second axis perpendicular to the first axis; first and second inertia tracks disposed to place the first and second pairs of chambers in fluid communication, respectively; and a plurality of elastic energy storage devices coupled to the first body and the second body and disposed to isolate vibrations between the first and second bodies.

Abstract: A system for image guided assembly of a structure, the structure defining an interior area accessible through at least one access opening, the interior area including at least one fastener hole. The system including a first fastening tool including an arm with first and second ends; and a support plate on the first end, the support plate including at least one connection member to securely retain a fastener therein, the at least one connection member configured to facilitate alignment of the fastener with the at least one fastener hole; an image capturing device disposed on the arm first end configured to generate a captured image of the interior area; a light source associated with the arm first end, the light source configured to generate light at the first end of the arm; and a display device located outside the interior area for displaying the captured image of the interior area.

Abstract: In one embodiment, a method is performed by a computer system in an aircraft. The method includes receiving an advance indication of a take-off or landing event to be executed by the aircraft in proximity to a landing area such that the landing area includes an arrangement of a plurality of emitters of electromagnetic radiation. The method further includes, responsive to the receiving, detecting, via a sensor in communication with the computer system, emission states of at least some of the plurality of emitters. In addition, the method includes transforming the detected emission states into an instruction set for the take-off or landing event. The method also includes initiating monitoring of the aircraft relative to the instruction set as the aircraft executes the take-off or landing event in proximity to the landing area.

Abstract: A rotor blade control system and methods therefor including a hub assembly pivotally attached to a rotor blade; a mast attached to the hub assembly; a swashplate assembly engaged with the mast and including a swashplate actuation mechanism pivotally coupled with the non-rotating ring at a plurality of coupling locations for moving the non-rotating ring and pivotally coupled with the base at a plurality of base locations, the swashplate actuation mechanism comprises a plurality of substantially triangular dual actuator assemblies that are independently and concurrently operable to move the respective coupling location so as to impart movement on the non-rotating ring. The swashplate actuation mechanism is configured to move the swashplate assembly about a longitudinal axis and a lateral axis in response to a cyclic input. The swashplate actuation mechanism is configured to move the swashplate assembly along the mast in response to a collective input.

Abstract: An aspect provides a skid landing gear assembly including a cross member disposed between a first skid tube and a second skid tube, and a tension cable member configured to be disposed in the cross member; wherein the tension cable member resists outward deflection of at least a portion of the skid landing gear assembly when a downward load is applied to the skid landing gear assembly. In other aspects, there are methods of avoiding ground resonance in a skid landing gear assembly, methods of assembling a skid landing gear assembly, methods of operating a helicopter with a skid landing gear assembly, and methods of improving the service life of a skid landing gear assembly.

Abstract: In one embodiment of the present disclosure, there is provided an aircraft having a bi-folding cowl for providing full access to equipment without completely removing the cowl. The bi-folding cowl has an upper portion and a lower portion mechanically connected along the adjacent edges, where the upper and lower portions fold so that the inner surfaces face each other when opened. In another embodiment, the bi-folding cowl has at least three maintenance positions, including partially-opened, fully-opened, and fully-opened, lying flat on the surface of the aircraft.