Abstract: A drone is disclosed having a low acoustic signature. The drone includes a fuselage, a main inboard wing attached to the fuselage, a pylon located towards an aft end of the fuselage and having an end that is higher than the main inboard wing, and a propulsor connected to the pylon and situated above the fuselage. The drone includes a plurality of booms connected to the main inboard wing and a plurality of horizontal tails attached to the plurality of booms. The horizontal tails have an outboard tail arrangement and are tiltable.

Abstract: A ducted wing is configured to be connected to an aircraft. The ducted wing includes an array of integrated jetfoils. Each jetfoil includes a propulsor fan, an upper wing portion, and a lower wing portion that extends past an end of the upper wing portion. Each jetfoil includes a duct formed between the upper wing portion and the lower wing portion where the propulsor is within the duct. Furthermore, each jetfoil may have one or more flaps at the leading edge or the trailing edge of the jetfoil. The jetfoil may have flaps that control either the inlet area or the outlet area of the propulsor fan as well as flaps that control whether the aircraft can operate in one of a plurality of different takeoff modes.

Abstract: A propulsor fan and drive system having reduced noise emission is disclosed. The propulsor fan includes a blade fan having a plurality of blades. The blades may include a dual pin-root design to secure the blade fan to a hub and a shroud at tips of the blades. The blades may include one or more knife edge seals that protrude from a surface of the shroud.

Abstract: A propulsor fan array having reduced noise emission is disclosed. The propulsor fan array includes a plurality of propulsor fans that collectively generate thrust. Each of the propulsor fans include a blade fan having a plurality of blades. The plurality of blades are tensioned at tips of the plurality of blade fans such that a pitch of the blades during thrust generation is substantially the same as a pitch of the blades at rest. By tensioning the tips of the blades, an angle of the blades is maintained during operation of the propulsor fan thereby reducing noise that may result from changes in the angle of the blades.

Abstract: A propulsor system comprising a propulsor and an exhaust area control mechanism are described. The exhaust area control mechanism is connected to an outlet of the propulsor and is configured to vary the area through which air exits the propulsor system.

Abstract: A propulsor fan array having reduced noise emission is disclosed. The propulsor fan array includes a plurality of propulsor fans that collectively generate thrust. Each of the propulsor fans include a blade fan having a plurality of blades. The plurality of blades are tensioned at tips of the plurality of blade fans such that a pitch of the blades during thrust generation is substantially the same as a pitch of the blades at rest. By tensioning the tips of the blades, an angle of the blades is maintained during operation of the propulsor fan thereby reducing noise that may result from changes in the angle of the blades.

Abstract: A propulsor fan and drive system having reduced noise emission is disclosed. The propulsor fan includes a blade fan having a plurality of blades. The blade fan is tensioned at the tips of the plurality of blades. By tensioning the tips of the blades, an angle of the blades is maintained during operation of the propulsor fan thereby reducing noise that may result from changes in the angle of the blades.