Described is an apparatus and method of an aerial vehicle, such as an unmanned aerial vehicle (“UAV”) that can operate in either a vertical takeoff and landing (VTOL) orientation or a horizontal flight orientation. The aerial vehicle includes a plurality of propulsion mechanisms that enable the aerial vehicle to move in any of the six degrees of freedom (surge, sway, heave, pitch, yaw, and roll) when in the VTOL orientation. The aerial vehicle also includes a ring wing that surrounds the propulsion mechanisms and provides lift to the aerial vehicle when the aerial vehicle is operating in the horizontal flight orientation.

The aircraft (10) comprises a fuselage (11) and a rhombohedral wing structure (12) comprising front wings (13, 14) mounted on a front wing-root support (17) and rear wings (15, 16) mounted on a rear wing-root support (18). One end of each front wing is articulated to one end of a rear wing and at least one of the wing-root supports is able to move along the fuselage. The wing-root supports (17, 18) are positioned respectively underneath and on top of the fuselage (11). The length (41) of the rear wings (15, 16) is strictly less than the length (48) of the front wings (13, 14). The aircraft (10) comprises an adaptor for adapting the position of each wing root (17, 18) to suit the flight conditions.

Vertical short takeoff and landing (VSTOL) aircraft include primary airfoils extending outwardly from a forward region of the aircraft fuselage, and secondary empennage airfoils extending outwardly from an aft region of the aircraft fuselage so as to be separated from the forward primary airfoils and thereby define a space therebetween which accommodates non-cyclic controllable propellers operably driven by a respective engine of a propulsion unit. The propulsion units are mounted for pivotal movement within the defined space between the primary airfoil and the secondary empennage airfoils so as to achieve a first operational position wherein the thrust line of the propellers is orientated substantially parallel to the longitudinal axis of the fuselage and a second operational position wherein the thrust line of the propellers is oriented substantially perpendicular to the longitudinal axis of the aircraft. The propulsion units may be mounted aft of the aircraft center of gravity (CG).

A vertical take-off and landing aircraft which uses fixed rotors for both VTOL and forward flight operations. The rotors form a synthetic wing and are positioned to achieve a high span efficiency. The rotors are positioned to even out the lift across the span of the synthetic wing. The synthetic wing may also have narrow front and rear airfoils which may provide structural support as well as providing lift during forward flight. The wing rotors are tilted forward and provide some forward propulsion during horizontal flight.

A vertical take-off and landing aircraft which uses fixed rotors for both VTOL and forward flight operations. The rotors form a synthetic wing and are positioned to achieve a high span efficiency. The rotors are positioned to even out the lift across the span of the synthetic wing. The synthetic wing may also have narrow front and rear airfoils which may provide structural support as well as providing lift during forward flight. The wing rotors are tilted forward and provide some forward propulsion during horizontal flight.

A method for the flying of a vertical take-off and landing aircraft which uses fixed rotors for both VTOL and forward flight operations. The rotors form a synthetic wing and are positioned to achieve a high span efficiency. The rotors are positioned to even out the lift across the span of the synthetic wing. The synthetic wing may also have narrow front and rear airfoils which may provide structural support as well as providing lift during forward flight, or may have a single center wing. The wing rotors are tilted forward and provide some forward propulsion during horizontal flight.

A method for the flying of a vertical take-off and landing aircraft which uses fixed rotors for both VTOL and forward flight operations. The rotors form a synthetic wing and are positioned to achieve a high span efficiency. The rotors are positioned to even out the lift across the span of the synthetic wing. The synthetic wing may also have narrow front and rear airfoils which may provide structural support as well as providing lift during forward flight, or may have a single center wing. The wing rotors are tilted forward and provide some forward propulsion during horizontal flight.

A damping landing gear assembly for a vertical takeoff and landing aircraft includes a spring housing forming a spring chamber, a spring disposed in the spring chamber and a plunger slidably coupled to the spring housing and movable between a compressed position and an extended position. The spring biases the plunger into the extended position during flight. The vertical takeoff and landing aircraft experiences a landing force during landing. The landing force compresses the plunger into the compressed position against the bias of the spring, thereby absorbing at least a portion of the landing force.

A damping landing gear assembly for a vertical takeoff and landing aircraft includes a spring housing forming a spring chamber, a spring disposed in the spring chamber and a plunger slidably coupled to the spring housing and movable between a compressed position and an extended position. The spring biases the plunger into the extended position during flight. The vertical takeoff and landing aircraft experiences a landing force during landing. The landing force compresses the plunger into the compressed position against the bias of the spring, thereby absorbing at least a portion of the landing force.

Systems and methods to improve controllability of an aerial vehicle responsive to degraded operational conditions are described. For example, one or more propeller blades of an aerial vehicle may be modifiable between two or more configurations. The configurations may include a low torque configuration suitable for normal operational conditions, and a high torque configuration suitable for degraded operational conditions. Various aspects or portions of a propeller blade may be modified to increase torque generated by the propeller blade due to drag or air resistance. The additional generated torque may then be used as a source of additional torque to improve controllability of the aerial vehicle responsive to degraded operational conditions.