The disclosure relates to a ducted fan aircraft propulsion system and to an aircraft incorporating such a propulsion system. Example embodiments include a ducted fan aircraft propulsion system (300), including: a duct (301); a central body portion (302) having first and second ends (303, 304) and extending through the duct (301); a payload portion (305) extending from the first end (303) of the central body portion (302); and a rotor (306) extending across an internal volume (307) of the duct (301) from the central body portion (302), wherein the duct (301) includes an outwardly flared inlet end (308) such that an inlet air flow passage (309) between the central body portion (302) and an inner surface (310) of the duct (301) has a sectional area that decreases from the inlet end (308) of the duct (301) to the rotor (306).

A vehicle, includes a main body. A fluid generator is coupled to the main body and produces a fluid stream. At least one tail conduit is fluidly coupled to the generator. First and second fore ejectors are coupled to the main body and respectively coupled to a starboard side and port side of the vehicle. The fore ejectors respectively comprise an outlet structure out of which fluid flows. At least one tail ejector is fluidly coupled to the tail conduit. The tail ejector comprises an outlet structure out of which fluid flows. A primary airfoil element includes a closed wing having a leading edge and a trailing edge. The leading and trailing edges of the closed wing define an interior region. The at least one propulsion device is at least partially disposed within the interior region.

An aircraft comprises a fuselage, first and second wing segments each having a leading edge and a trailing edge, a plurality of spokes coupling the fuselage to the first and second wing segments, one or more motors disposed within or attached to the plurality of spokes, and three or more propellers proximate to a leading edge of the plurality of spokes, distributed along the plurality of spokes, and operably connected to the motors to provide lift whenever the aircraft is in vertical takeoff and landing and stationary flight and provide thrust whenever the aircraft is in forward flight. When the aircraft is in vertical takeoff and landing and stationary flight, the fuselage is approximately vertical. When the aircraft is in forward flight, the fuselage is approximately in the direction of the forward flight and extends forward beyond the leading edges of the first wing segment and the second wing segment.

An airframe design may include a frame or assembly, and one or more components that may be removably attached to the frame. The frame may include struts, central bulkheads, a tail section, a plurality of wing sections, and motor mounts that are attached together. The one or more attachable components may include a forward fuselage, motors, propellers, motor pod fairings, stabilizer fins, and landing gear that are attached using fasteners. The frame may reduce the number of parts of the airframe design and may also reduce complexity, cost, and weight, while also increasing stiffness and strength. Further, the various attachable components may facilitate fabrication, assembly, and maintenance of an aerial vehicle having the airframe design.