Abstract: Embodiments are directed to boosting aircraft engine performance for takeoff and critical mission segments by reducing airflow used for cooling exhaust gases. The airflow is reduced by stopping an accessory blower or by closing an external air vent Eliminating the cooling airflow to the exhaust has the effect of lowering the backpressure on the engine, which thereby increases maximum engine power.

Abstract: An adjustable length crank arm includes a first component having a longitudinal length, a second component coupled to the first component, the second component having a longitudinal length. A total length of the crank arm can be adjusted by changing an amount of longitudinal overlap that exists between the first component and the second component. The adjustable length crank arm can include a first wedge and a second wedge and at least a portion of each of the first wedge and the second wedge is longitudinally captured between the first component and the second component.

Abstract: An aircraft includes an airframe with first and second wings having a fuselage extending therebetween. A propulsion assembly is coupled to the fuselage and includes a counter-rotating coaxial rotor system that is tiltable relative to the fuselage to generate a thrust vector. First and second yaw vanes extend aftwardly from the fuselage. A flight control system is configured to direct the thrust vector of the coaxial rotor system and control movements of the yaw vanes. In a VTOL orientation of the aircraft, differential operation of the yaw vanes and/or differential operations of first and second rotor assemblies of the coaxial rotor system provide yaw authority for the aircraft. In a biplane orientation of the aircraft, collective operation of the yaw vanes provides yaw authority for the aircraft.

Abstract: A power management system for a multi engine rotorcraft having a main rotor system with a main rotor speed. The power management system includes a first engine that provides a first power input to the main rotor system. A second engine selectively provides a second power input to the main rotor system. The second engine has at least a zero power input state and a positive power input state. A power anticipation system is configured to provide the first engine with a power adjustment signal in anticipation of a power input state change of the second engine during flight. The power adjustment signal causes the first engine to adjust the first power input to maintain the main rotor speed within a predetermined rotor speed threshold range during the power input state change of the second engine.

Abstract: An aircraft comprises a fuselage, one or more support structures connected to the fuselage, one or more engines or motors disposed within or attached to the one or more support structures or the fuselage, and a distributed propulsion system. The distributed propulsion system comprising two or more propellers symmetrically distributed in an array along the one or more support structures with respect to a center of gravity of the aircraft and operably connected to the one or more engines or motors, wherein each propeller has a rotation direction within a tilted plane of rotation, and a summation of horizontal force vectors created by the tilted plane of rotation of all the propellers is substantially zero when all the propellers are creating a substantially equal thrust magnitude. Movement of the aircraft is controlled by selectively increasing or decreasing a thrust of at least one of the two or more propellers.

Abstract: A coaxial rotor system for a rotorcraft includes a mast, a top rotor assembly and a bottom rotor assembly. The top rotor assembly is coupled to the distal end of the mast. The bottom rotor assembly includes a motor configured to provide rotational energy to the mast, thereby rotating the top rotor assembly. The bottom rotor assembly experiences a torque reaction force responsive to the motor rotating the mast such that the top and bottom rotor assemblies counter rotate.

Abstract: An aircraft has multiple independent yaw authority mechanisms. The aircraft includes an airframe having first and second wings with at least first and second pylons extending therebetween and with a plurality of tail members extending therefrom each having an active control surface. A two-dimensional distributed thrust array is coupled to the airframe that includes a plurality of propulsion assemblies each having a rotor assembly and each operable for thrust vectoring. A flight control system is operable to independently control each of the propulsion assemblies. A first yaw authority mechanism includes differential speed control of rotor assemblies rotating clockwise compared to rotor assemblies rotating counterclockwise. A second yaw authority mechanism includes differential longitudinal control surface maneuvers of control surfaces of two symmetrically disposed tail members. A third yaw authority mechanism includes differential thrust vectoring of propulsion assemblies.

Abstract: A rotor assembly for generating thrust for a vehicle. The rotor assembly includes a rotor hub and a plurality of rotor blade assemblies coupled to the rotor hub. Each rotor blade assembly includes a metallic bearing race, a composite rotor blade and a metallic coupling assembly. The composite rotor blade has a root section with a radially outwardly tapered outer surface. The metallic coupling assembly has a radially inwardly tapered inner surface that receives the radially outwardly tapered outer surface of the root section of the rotor blade therein to provide a centrifugal force seat for the rotor blade. The coupling assembly includes at least two circumferentially distributed coupling members. The coupling assembly is configured to couple the rotor blade to the bearing race and to provide a centrifugal force load path therebetween.

Abstract: Embodiments are directed to a rotor blade comprising a blade tip attached to the outboard end of the rotor blade. The blade tip has at least two sides that are tapered together to an edge. The length of the blade tip extending away from the outboard end to the edge is a distance that is greater than half the thickness of the outboard end. When the rotor blade is operating in a folded configuration, air flows over the sides in a direction generally parallel to a longitudinal axis of the rotor blade. The sides have profiles that minimize or prevent separation of the air flow from the blade tip.

Abstract: One embodiment is a navigation system for an aircraft including a positioning system to generate information related to a position of the aircraft, a group of cameras mounted to a body of the aircraft, each camera of the group of cameras to simultaneously capture images of a portion of an environment that surrounds the aircraft, and a processing component coupled to the positioning system and the group of cameras, the processing component to determine a current position of the aircraft based on the information related to the position of the aircraft and the images.

Abstract: A swashplate assembly includes: a mounting sleeve configured for coupling to and around an upper portion of a gearbox, wherein the mounting sleeve extends downwards from the upper portion of the gearbox; a tilt sleeve coupled to the mounting sleeve, wherein the tilt sleeve has a curved exterior surface; a non-rotating swashplate ring positioned around the tilt sleeve, wherein the non-rotating swashplate ring has a first set of pitch control connectors and an anti-rotation connector; a rotating swashplate ring rotatable about the non-rotating swashplate ring, wherein the rotating swashplate ring has a second set of pitch control connectors and a drive link connector; and a first bearing system mounted between the non-rotating swashplate ring and the rotating swashplate ring.

Abstract: An air intake system for an aircraft, which is switchable between a performance mode and a filtered mode, includes a duct forming filtered air inlet slits. The air intake system also includes interconnected gills adjacent to the filtered air inlet slits. The gills are movable between various gill positions including a closed position substantially covering the filtered air inlet slits and an open position substantially exposing the filtered air inlet slits. The air intake system also includes an actuator configured to move the gills into the closed position in the performance mode and the open position in the filtered mode.

Abstract: An exemplary unmanned aerial vehicle (UAV) mountable to a conductor of an aerial power transmission line system includes a body having a rotor system, a motivation system attached to the body to motivate the UAV along the conductor, a battery carried by the body and electrically connected to at least one of the rotor system and the motivation system, a monitoring tool mounted with the body and an inductive coil carried by the body and in electric connection with the battery, wherein the inductive coil is configured to harvest electricity from the aerial power transmission line system and charge the battery.

Abstract: An aircraft operable to transition between thrust-borne lift in a VTOL orientation and wing-borne lift in a biplane orientation. The aircraft has an airframe including first and second wings with first and second pylons coupled therebetween. A distributed thrust array is coupled to the airframe including a plurality of propulsion assemblies coupled to the first wing and a plurality of propulsion assemblies coupled to the second wing. A UAV carrier assembly is coupled between the first and second pylons. The UAV carrier assembly has a plurality of UAV stations each configured to selectively transport and release a UAV. A flight control system is configured to control each of the propulsion assemblies and launch each of the UAVs during flight.

Abstract: A duct for a ducted-rotor aircraft may include internal structural components such as a spindle that is supported by a fuselage of the aircraft, first and second annular spars that are attached to an end of the spindle, a central hub that supports a motor of the aircraft, a plurality of stators that extend from the central hub to the second spar, and a plurality of ribs that are attached to the first spar and the second spar at respective opposed ends. The spindle may include an attachment interface to which the first and second spars are attached. The attachment interface may be disposed at the second end of the spindle. The attachment interface may define first and second arc-shaped planar surfaces to which the first and second spars, respectively, are attached.

Abstract: A ground state determination system for an aircraft includes sensors configured to detect parameters of the aircraft and a flight control system implementing a ground state module. The ground state module includes a ground state monitoring module configured to monitor the parameters and a ground state determination module configured to compare each of the parameters monitored by the ground state monitoring module to a respective parameter threshold to determine whether the aircraft is on a surface.

Abstract: A landing gear for an aircraft includes a landing strut having proximal and distal ends with the proximal end couplable to the fuselage of the aircraft. The landing strut includes a gas chamber, a liquid chamber, a cylinder and a piston that is movable relative to the cylinder between extended and retracted positions. A wheel is coupled to the distal end of the landing strut. A force sensor is disposed between an extend stop surface of the piston and the chamber. Pressurized gas in the gas chamber biases the piston to the extended position such that the force sensor experiences a preload force. The force sensor is configured to detect a reduction in the preload force during a landing maneuver responsive to contact between the wheel and a landing surface.

Abstract: A wing apparatus and aircraft are described providing greater maneuverability and efficiency for vertical takeoff and landing vehicles. Use of a fowler flap is shown in combination with a sliding panel. The sliding panel can nest within a wing similar to a fowler flap. During vertical maneuvers the sliding panel can be moved forward and on top of the wing. This can alleviate download during vertical maneuvers while minimizing drag as forward flight begins.

Abstract: A ring gear assembly includes a ring gear, a gear box case, and a set of bolts. The ring gear includes a set of gear teeth inside the ring gear and arranged in a circle around the ring gear axis. The ring gear further includes a set of flanges arranged along at least one side of the ring gear. Each flange has a respective flange bolt hole therethrough, and each flange bolt hole has a respective bolt axis that is oriented perpendicular to the ring gear axis. The gear box case has a set of gear box bolt holes therethrough, each gear box bolt hole corresponding to a respective one of the flange bolt holes. Each of the bolts passes through a respective one of the gear box bolt holes and its corresponding flange bolt hole to fasten the ring gear to the gear box case.

Abstract: A technique of managing communications among multiple modules of a munition includes receiving, by a first module of the munition, a first set of messages from a second module of the munition. The first set of messages is received in a first protocol used for communicating among the modules of the munition over a computer network. The technique further includes translating, by an interface assembly of the first module, the first set of messages in the first protocol into a second set of messages in a second protocol. The second protocol is a native protocol of the first module and is different from the first protocol. The technique still further includes providing the second set of messages from the interface module to an operational component of the first module, the operational component then responding to the second set of messages for performing a function of the munition.