An aircraft structural component, for example, a wing spar that has an I-beam shape having upper and lower spar caps coupled by a web therebetween and that provides structural support for an aircraft wing. The wing spar may be fabricated as a graphite composite that is thermally cured to have a certain stiffness. In one embodiment, the wing spar is fabricated so that the upper spar cap has a higher CTE than the web, which creates tension forces in the spar cap when the spar is thermally cured and then cooled. Therefore, when the wing spar is mounted to the wing and the aircraft is in flight, compression forces on the wing skin act to relieve the tension forces in the spar cap, which reduces the compression buckling load on the wing.

An aircraft can include a frame and a plurality of electrical rotors coupled to the frame. The aircraft can further include a control system physically coupled to the frame and communicatively coupled with each of the plurality of electrical rotors. The control system can be configured to control a speed of each electrical rotor on an individual basis to control a direction of flight of the aircraft. The aircraft can further include an engine coupled to the frame, the engine being configured to combust a combustible fuel to generate thrust.

An aircraft structural component, for example, a wing spar that has an I-beam shape having upper and lower spar caps coupled by a web therebetween and that provides structural support for an aircraft wing. The wing spar may be fabricated as a graphite composite that is thermally cured to have a certain stiffness. In one embodiment, the wing spar is fabricated so that the upper spar cap has a higher CTE than the web, which creates tension forces in the spar cap when the spar is thermally cured and then cooled. Therefore, when the wing spar is mounted to the wing and the aircraft is in flight, compression forces on the wing skin act to relieve the tension forces in the spar cap, which reduces the compression buckling load on the wing.

A coupling device for supporting a first wing section against a second wing section of an aircraft, and configured for passive flight load alleviation includes a housing including a chamber including a first portion and a second portion and filled with a fluid, a piston device movably arranged in the chamber and separating the first portion from the second portion in a fluid tight manner, a first fluid pathway connecting the first portion to the second portion, a first pressure relief valve arranged in the first fluid pathway and blocking the first fluid pathway, if the pressure in the second portion is smaller than a first relief pressure and opening the first fluid pathway, if the pressure in the second portion is greater than the first relief pressure. In addition, the coupling device can be used to actuate the second wing section against the first wing section.

A coupling device for supporting a first wing section against a second wing section of an aircraft, and configured for passive flight load alleviation includes a housing including a chamber including a first portion and a second portion and filled with a fluid, a piston device movably arranged in the chamber and separating the first portion from the second portion in a fluid tight manner, a first fluid pathway connecting the first portion to the second portion, a first pressure relief valve arranged in the first fluid pathway and blocking the first fluid pathway, if the pressure in the second portion is smaller than a first relief pressure and opening the first fluid pathway, if the pressure in the second portion is greater than the first relief pressure. In addition, the coupling device can be used to actuate the second wing section against the first wing section.

Airframes configured for stable in-flight transition between forward flight and vertical takeoff and landing are described herein. In one embodiment, an aircraft can include a fuselage, opposed wings extending from opposed sides of the fuselage, and a plurality of engines. At least one engine can be mounted to each of the opposed wings and at least a portion of each opposed wing including at least one of the plurality of engines can rotate relative to the fuselage around a rotation axis that is non-perpendicular and transverse to a longitudinal axis of the fuselage. Rotating portions of the wings including at least one of the plurality of engines in the described manner can provide a stable and smooth transition between vertical and forward flight.

Airframes configured for stable in-flight transition between forward flight and vertical takeoff and landing are described herein. In one embodiment, an aircraft can include a fuselage, opposed wings extending from opposed sides of the fuselage, and a plurality of engines. At least one engine can be mounted to each of the opposed wings and at least a portion of each opposed wing including at least one of the plurality of engines can rotate relative to the fuselage around a rotation axis that is non-perpendicular and transverse to a longitudinal axis of the fuselage. Rotating portions of the wings including at least one of the plurality of engines in the described manner can provide a stable and smooth transition between vertical and forward flight.

A method of controlling a magnitude of a sonic boom caused by off-design-condition operation of a supersonic aircraft at supersonic speeds includes, but is not limited to the step of operating the supersonic aircraft at supersonic speeds and at an off-design-condition. The supersonic aircraft has a pair of swept wings having a plurality of composite plies oriented at an angle such that an axis of greatest stiffness is non-parallel with respect to a rear spar of each wing of the pair of swept wings. The method further includes, but is not limited to the step of reducing wing twist caused by operation of the supersonic aircraft at supersonic speeds at the off-design condition with the composite plies. The method still further includes, but is not limited to, minimizing the magnitude of the sonic boom through reduction of wing twist.

A method of controlling a magnitude of a sonic boom caused by off-design-condition operation of a supersonic aircraft at supersonic speeds includes, but is not limited to the step of operating the supersonic aircraft at supersonic speeds and at an off-design-condition. The supersonic aircraft has a pair of swept wings having a plurality of composite plies oriented at an angle such that an axis of greatest stiffness is non-parallel with respect to a rear spar of each wing of the pair of swept wings. The method further includes, but is not limited to the step of reducing wing twist caused by operation of the supersonic aircraft at supersonic speeds at the off-design condition with the composite plies. The method still further includes, but is not limited to, minimizing the magnitude of the sonic boom through reduction of wing twist.

Systems, apparatuses, and methods are provided herein for unmanned flight optimization. A system for unmanned flight comprises a set of motors configured to provide locomotion to an unmanned aerial vehicle, a set of wings coupled to a body of the unmanned aerial vehicle via an actuator and configured to move relative to the body of the unmanned aerial vehicle, a sensor system on the unmanned aerial vehicle, and a control circuit. The control circuit being configured to: control the unmanned aerial vehicle, cause the set of motors to lift the unmanned aerial vehicle, detect condition parameters based on the sensor system, determine a position for the set of wings based on the condition parameters, and cause the actuator to move the set of wings to the wing position while the unmanned aerial vehicle is in flight.