Systems, devices, and methods including an unmanned aerial vehicle (UAV); one or more inner wing panels of the UAV; one or more outer wing panels of the UAV; at least one inboard propeller attached to at least one engine disposed on the one or more inner wing panels; at least one tip propeller attached to at least one engine disposed on the one or more outer wing panels; at least one microcontroller configured to: determine an angular position of the at least one inboard propeller; and send a signal to halt rotation of the at least one inboard propeller such that the at least one inboard propeller is held in an attitude that provides for clearance of the propeller blade to the ground upon landing.

Systems, devices, and methods including an unmanned aerial vehicle (UAV); one or more inner wing panels of the UAV; one or more outer wing panels of the UAV; at least one inboard propeller attached to at least one engine disposed on the one or more inner wing panels; at least one tip propeller attached to at least one engine disposed on the one or more outer wing panels; at least one microcontroller configured to: determine an angular position of the at least one inboard propeller; and send a signal to halt rotation of the at least one inboard propeller such that the at least one inboard propeller is held in an attitude that provides for clearance of the propeller blade to the ground upon landing.

An airfoil segment for inclusion in an aircraft wing is provided. The multi-element slotted airfoil segment has at least one propeller operatively located in a slot communicating therethrough for improved low speed performance and control. Upstream propeller flow field effects generated allow the front portion of the airfoil segment to be structurally efficient thicker airfoils with higher lift-to-drag laminar airfoils or higher maximum lift coefficient designs. The downstream propeller flow field acting on the aft portion of the airfoil segment increases lift and allows flaps on the aft portion to provide control forces/moments at static or low flight speeds for short or vertical take-off.

A Short Takeoff and Landing (STOL) aircraft has a fuselage with an axis and an engine providing thrust, a first aileron at an end of a first wing, a second aileron at an end of a second wing, a first slot having a length through the first wing proximate the first aileron, orthogonal to the axis; a second slot having a length through the second wing proximate the second aileron, orthogonal to the axis; a first electric motor in the first wing driving a first two-blade propeller in the first slot, a second electric motor in the second wing driving a second two-blade propeller in the second slot, and a control mechanism enabling a user to drive the first and second electric motors in a same rotary direction, to reverse the rotary direction, and to drive the first and second motors at a same rpm.

A Short Takeoff and Landing (STOL) aircraft has a fuselage with an axis and an engine providing thrust, a first aileron at an end of a first wing, a second aileron at an end of a second wing, a first slot having a length through the first wing proximate the first aileron, orthogonal to the axis; a second slot having a length through the second wing proximate the second aileron, orthogonal to the axis; a first electric motor in the first wing driving a first two-blade propeller in the first slot, a second electric motor in the second wing driving a second two-blade propeller in the second slot, and a control mechanism enabling a user to drive the first and second electric motors in a same rotary direction, to reverse the rotary direction, and to drive the first and second motors at a same rpm.

An aircraft portion includes a fuselage oriented in a longitudinal direction, an airfoil made up of at least one pair of wings arranged on either side of the fuselage in a transverse direction orthogonal to the longitudinal direction, and an airfoil-fuselage junction fairing at the interface between the airfoil and the fuselage. The junction fairing has, in a vertical plane, a lower profile and, in a horizontal plane, a horizontal profile at the junction of the outer surface of the junction fairing with the convex side of each wing. The horizontal profile and/or the lower profile successively has, in the longitudinal direction, a convex front segment, a concave intermediate segment, and a convex rear segment.

An aircraft portion includes a fuselage oriented in a longitudinal direction, an airfoil made up of at least one pair of wings arranged on either side of the fuselage in a transverse direction orthogonal to the longitudinal direction, and an airfoil-fuselage junction fairing at the interface between the airfoil and the fuselage. The junction fairing has, in a vertical plane, a lower profile and, in a horizontal plane, a horizontal profile at the junction of the outer surface of the junction fairing with the convex side of each wing. The horizontal profile and/or the lower profile successively has, in the longitudinal direction, a convex front segment, a concave intermediate segment, and a convex rear segment.

An aircraft equipped with a distributed fan propulsion system and methods of operating such aircraft are provided. In one aspect, an aircraft includes a wing having a top surface and a bottom surface. The aircraft also has a distributed propulsion system that includes a suction fan array having one or more fans mounted to the wing and a pressure fan array having one or more fans mounted to the wing. The fans of the suction fan array are each positioned primarily above the top surface of the wing and the fans of the pressure fan array are each positioned primarily below the bottom surface of the wing. The fans of the suction fan array are controllable independent of the fans of the pressure fan array so that the air pressure above and/or below the wing can be locally controlled, allowing for adjustment of lift on the wing.

Systems, devices, and methods including an unmanned aerial vehicle (UAV); one or more inner wing panels of the UAV; one or more outer wing panels of the UAV; at least one inboard propeller attached to at least one engine disposed on the one or more inner wing panels; at least one tip propeller attached to at least one engine disposed on the one or more outer wing panels; at least one microcontroller configured to: determine an angular position of the at least one inboard propeller; and send a signal to halt rotation of the at least one inboard propeller such that the at least one inboard propeller is held in an attitude that provides for clearance of the propeller blade to the ground upon landing.

Systems, devices, and methods including an unmanned aerial vehicle (UAV); one or more inner wing panels of the UAV; one or more outer wing panels of the UAV; at least one inboard propeller attached to at least one engine disposed on the one or more inner wing panels; at least one tip propeller attached to at least one engine disposed on the one or more outer wing panels; at least one microcontroller configured to: determine an angular position of the at least one inboard propeller; and send a signal to halt rotation of the at least one inboard propeller such that the at least one inboard propeller is held in an attitude that provides for clearance of the propeller blade to the ground upon landing.