An airfoil structure for an aircraft includes a spanwise-extending load-carrying member, a leading-edge structure, a trailing-edge structure, an upper cover, and a lower cover. The load-carrying member is configured to react more than half of all flight loads experienced by the airfoil structure during flight and is configured to have selected stiffness properties selected such that the airfoil structure bends and twists in a predefined manner in response to applied flight loads. The leading-edge structure is configured to form a leading-edge part of an aerodynamic surface of the airfoil structure. The trailing-edge structure is configured to form a trailing edge part of the aerodynamic surface. The upper cover is configured to form an upper part of the aerodynamic surface. The lower cover is configured to form a lower part of the aerodynamic surface.

The aircraft can include: an airframe, a tilt mechanism, a payload housing, and can optionally include an impact attenuator, a set of ground support members (e.g., struts), a set of power sources, and a set of control elements. The airframe can include: a set of rotors and a set of support members. By utilizing a larger rotor blade area (and/or larger rotor disc area) and adjusting the blade pitch and RPM, the rotors can augment the lift generated by the aerodynamic profile of the aircraft in the forward flight mode in addition to providing forward thrust. Variants generating lift with the rotors can reduce or eliminate additional control surfaces (e.g., wing flaps, ailerons, ruddervators, elevators, rudder, etc.) on the aircraft since the thrust and motor torque is controllable (thereby indirectly controlling lift) at each rotor, thereby enabling pitch, yaw, and/or roll control during forward flight.

The aircraft can include: an airframe, a tilt mechanism, a payload housing, and can optionally include an impact attenuator, a set of ground support members (e.g., struts), a set of power sources, and a set of control elements. The airframe can include: a set of rotors and a set of support members. By utilizing a larger rotor blade area (and/or larger rotor disc area) and adjusting the blade pitch and RPM, the rotors can augment the lift generated by the aerodynamic profile of the aircraft in the forward flight mode in addition to providing forward thrust. Variants generating lift with the rotors can reduce or eliminate additional control surfaces (e.g., wing flaps, ailerons, ruddervators, elevators, rudder, etc.) on the aircraft since the thrust and motor torque is controllable (thereby indirectly controlling lift) at each rotor, thereby enabling pitch, yaw, and/or roll control during forward flight.

One embodiment includes a rotary aircraft, including: a main drive rotor; an aircraft body mechanically coupled to the main drive rotor; and first and second flight assist wings passively rotatably coupled to the aircraft body.

In various embodiments, a tilt-wing aircraft includes a fuselage; a first wing tiltably mounted at or near a forward end of the fuselage; and a second wing rotatably mounted to the fuselage at a position aft of the first wing. A first plurality of rotors is mounted on the first wing at locations on or near a leading edge of the first wing, with two or more rotors being mounted on wing portions on each side of the fuselage; and a second plurality of rotors mounted on the second wing at locations on or near a leading edge of the second wing, with two or more rotors being mounted on wing portions on each side of the fuselage. A flight control system generates a set of actuators and associated actuator parameters to achieve desired forces and moments.

A multi-boom aircraft with an adjustable wing geometric twist includes at least one wing, and at least three booms arranged transversely to at least one of the wings. Each of the booms includes at least one actuator, and the at least one wing is mounted on the booms so as at least a portion of the corresponding wing can be pivoted by means of the actuators about an axis extending substantially along the corresponding wing.

Provided is a tailstock type vertical take-off and landing unmanned aerial vehicle and a control method thereof. The unmanned aerial vehicle is mainly composed of a fuselage, wings, ailerons, empennages, an elevator, a rudder, an engine, an attitude adjustment nozzle, a landing gear, and the like. The wings are symmetrically arranged on both sides of the middle of the fuselage; the ailerons are hinged to the trailing edges of the wings on the both sides; the empennages are located at the tail of the fuselage, and a form of vertical empennages+horizontal empennages or V-shaped empennages can be used; the elevator and rudder are hinged to the trailing edges of the empennages; the engine is arranged at the tail of the fuselage for producing main thrust.

VTOL aircraft that takeoff and land as a multirotor and cruises as airplane. The aircraft comprises two major parts: First; winged carrier frame comprises wings, engines, propellers and landing gears. Second; tilting fuselage comprises cockpit, cabin and tail. Winged carrier frame is basically X/H frame multirotor that its thruster carrying arms are wing shaped. Aircraft vertically takeoff as multirotor after gaining safe altitude and forward airspeed then changes its flying axis that wings and thrust direction parallel to horizon. Lift generated by wings and thrust generated by thrusters that aircraft has basic airplane flying characteristics. Fuselage tilted to keep payload parallel to the horizon. Speed reduced, winged carrier frame and fuselage returned to multirotor for landing. It is easier to rotate fuselage than thrusters or wings. It is better to adjust thrust levels than vectoring to reduce the moving parts and aerodynamic effects.

A propulsion system of an aircraft has at least one unducted fan and at least one ducted fan, the at least one unducted fan and the at least one ducted fan being powered by an electric power source and rotatable between a vertical thrust position and a forward thrust position, and a controller configured to distribute electrical power between the at least one unducted fan and the at least one ducted fan. During a first mode when the at least one unducted fan and the at least one ducted fan are in the vertical thrust position, the controller is configured to distribute the electrical power between the plurality of unducted fans and the plurality of ducted fans such that the at least one unducted fan is a primary source of thrust.

A multirotor aircraft that includes a chassis, three or more vertical rotors, one or more free wings and on ore more fixed horizontal rotor. The free wing is attached to the chassis by an axial connection so that the angle of the free wing is changed relative to the chassis according the flow of air over the free wing. The fixed horizontal rotor enables the multirotor aircraft to lower and climb while flying forward at a stable horizontal pitch of the chassis.