An aerial vehicle control surface actuation system comprises a rotary actuator having opposing output shaft ends that are coupled to first and second torque tubes via actuator universal joints. The first and second torque tubes extend angularly from the rotary actuator. The system further comprises first and second pivot joints that are coupled to a hinged end of a control surface. The first and second pivot joints are coupled to the first and second torque tubes, respectively, via control surface universal joints. In this configuration, rotation of the first and second torque tubes causes rotation of the control surface relative to a hinge axis.

A bearing assembly of a hinge coupling first and second components includes an outer ring secured to the second component having an axial primary bore with a primary inner surface. An inner ring axially rotates, and has a primary outer surface rollingly contacting the primary inner surface, defining a primary sliding path with a primary friction coefficient. The inner ring includes a secondary axial bore with a secondary inner surface. An inner shaft in the secondary bore is secured to the first component and is axially rotatable. The inner shaft has a secondary outer surface rollingly contacting the secondary inner surface defining a secondary sliding path with a second friction coefficient. One of the sliding paths has a triboelectric layer surface frictionally generating an electrical current when that sliding path is engaged. A transmission element transmits, to a failure detection system, a signal due to such electrical current.

A control surface for an aircraft may comprise an outer skin and a core coupled to the outer skin. The core may include a plurality of corrugations. A height of the core may decrease in a direction extending from a leading edge of the control surface to a trailing edge of the control surface.

A control surface for an aircraft may comprise an outer skin and a core coupled to the outer skin. The core may include a plurality of corrugations. A height of the core may decrease in a direction extending from a leading edge of the control surface to a trailing edge of the control surface.

A propulsion assembly for an aircraft operable to transition between thrust-borne lift in a VTOL orientation and wing-borne lift in a biplane orientation. The propulsion assembly includes a housing coupled to the fuselage of the aircraft. A coaxial rotor system includes a first rotor assembly and a second rotor assembly that are rotatable about a common axis of rotation. The first rotor assembly counter-rotates relative to the second rotor assembly. A motor assembly is operably associated with the coaxial rotor system. The motor assembly provides torque and rotational energy to the first rotor assembly and the second rotor assembly. A gimbal assembly couples the coaxial rotor system to the housing such that the coaxial rotor system is tiltable relative to the fuselage to generate a thrust vector.

A vertical landing and take-off aircraft VTOL transitions from a vertical takeoff state to a cruise state where the vertical takeoff state uses propellers to generate lift and the cruise state uses wings to generate lift. The aircraft has an M-wing configuration with propellers located on the wingtip nacelles, wing booms, and tail boom. The wing boom and/or the tail boom can include boom control effectors. Hinged control surfaces on the wings, tail boom, and tail tilt during takeoff and landing to yaw the vehicle. The boom control effectors, cruise propellers, stacked propellers, and control surfaces can have different positions during different modes of operation in order to control aircraft movement and mitigate noise generated by the aircraft.

A vertical landing and take-off aircraft VTOL transitions from a vertical takeoff state to a cruise state where the vertical takeoff state uses propellers to generate lift and the cruise state uses wings to generate lift. The aircraft has an M-wing configuration with propellers located on the wingtip nacelles, wing booms, and tail boom. The wing boom and/or the tail boom can include boom control effectors. Hinged control surfaces on the wings, tail boom, and tail tilt during takeoff and landing to yaw the vehicle. The boom control effectors, cruise propellers, stacked propellers, and control surfaces can have different positions during different modes of operation in order to control aircraft movement and mitigate noise generated by the aircraft.

A quench and temper steel alloy is disclosed having the following composition in weight percent. TABLE-US-00001 C 0.1-0.4 Mn 0.1-1.0 Si 0.1-1.2 Cr 9.0-12.5 Ni 3.0-4.3 Mo   1-2 Cu 0.1-1.0 Co   1-4 W  0.2 max. V 0.1-0.6 Ti  0.1 max. Nb up to 0.01 Ta up to 0.01 Al   0-0.25 N 0.1-0.35 Ce 0.006 max. La 0.006 max.
The balance of the alloy is iron and the usual impurities found in similar grades of quench and temper steels intended for similar use or service, including not more than about 0.01% phosphorus and not more than about 0.010% sulfur. A quenched and tempered steel article made from this alloy is also disclosed. Further disclosed is a method of making the alloy.

A quench and temper steel alloy is disclosed having the following composition in weight percent. TABLE-US-00001 C 0.1-0.4 Mn 0.1-1.0 Si 0.1-1.2 Cr 9.0-12.5 Ni 3.0-4.3 Mo   1-2 Cu 0.1-1.0 Co   1-4 W  0.2 max. V 0.1-0.6 Ti  0.1 max. Nb up to 0.01 Ta up to 0.01 Al   0-0.25 N 0.1-0.35 Ce 0.006 max. La 0.006 max.
The balance of the alloy is iron and the usual impurities found in similar grades of quench and temper steels intended for similar use or service, including not more than about 0.01% phosphorus and not more than about 0.010% sulfur. A quenched and tempered steel article made from this alloy is also disclosed. Further disclosed is a method of making the alloy.

A wing for an aircraft, including a main wing, and a leading edge high lift assembly including a high lift body, and a connection assembly connecting the high lift body to the main wing such that the high lift body is movable relative to the main wing between stowed and deployed positions. The connection assembly includes a first connection element mounted to the high lift body and movably mounted to the main wing. The connection assembly includes a second connection element mounted to the high lift body spaced apart from the first connection element in a span direction, and movably mounted to the main wing. The connection assembly includes an additional support device arranged spaced apart from the first and second connection elements and configured to support the high lift body at the main wing against movement or deformation of the high lift body relative to the main wing.