A propulsion system for an aircraft includes at least one gas turbine engine, an electric auxiliary fan driving motor configured to selectively receive electric power input from one or more electric power sources, and at least one auxiliary propulsion fan configured to selectively receive a motive force from either or both of the at least one gas turbine engine and the electric auxiliary fan driving motor. The propulsion system also includes a controller configured to establish a plurality of takeoff thrust settings of the at least one gas turbine engine and the electric auxiliary fan driving motor such that a minimum total aircraft thrust required for takeoff of the aircraft is produced.

Technologies are described herein for a drag recovery scheme. In various examples, a recovery engine is placed within a vortex flow of air caused by the impingement of air upon a nacelle of a main engine. The propeller of the recovery engine can use the vortex flow of air to provide additional thrust the aircraft, thus reducing the load on the main engines or providing an increased velocity.

An assembly is provided for an aerial vehicle. This assembly includes an airframe and a fluid circuit. The airframe includes a body and an airfoil projecting out from the body. The airfoil includes a first surface and a first aperture in the first surface. The fluid circuit is configured to bleed gas from a gas turbine engine mounted to the airframe to provide control gas. The fluid circuit is configured to selectively direct the control gas to the first aperture.

An assembly is provided that includes a regulator manifold and a regulator element. The regulator manifold includes an inlet passage, a first outlet passage and a second outlet passage. The inlet passage is configured to receive bleed gas from a core flowpath. The regulator element is within the regulator manifold and configured to pivot to a first position, a second position and an intermediate position between the first position and the second position. The regulator element is configured to fluidly couple the inlet passage with the first outlet passage in the first position. The regulator element is configured to fluidly couple the inlet passage with the second outlet passage in the second position. The regulator element is configured to fluidly decouple the inlet passage from the first outlet passage and the second outlet passage in the intermediate position.

A supersonic flow system in which a supersonic flow is encountered includes a surface configured to be exposed to a supersonic fluid flow, wherein the surface includes an upstream end and a downstream end opposite the upstream end, a wave generator coupled to the surface and including one or more actuators configured to selectably induce strain in the surface, and a wave controller in signal communication with the wave generator and configured to activate the one or more actuators to induce one or more travelling waves configured to travel along the surface between the upstream end and the downstream end of the surface.

A supersonic flow system in which a supersonic flow is encountered includes a surface configured to be exposed to a supersonic fluid flow, wherein the surface includes an upstream end and a downstream end opposite the upstream end, a wave generator coupled to the surface and including one or more actuators configured to selectably induce strain in the surface, and a wave controller in signal communication with the wave generator and configured to activate the one or more actuators to induce one or more travelling waves configured to travel along the surface between the upstream end and the downstream end of the surface.

An aircraft is provided including a boundary layer ingestion fan mounted to an aft end of a fuselage. A stabilizer is mounted to the fuselage and extends between a root portion and a tip portion to define a span-wise length and extends between a leading edge and a trailing edge along the longitudinal direction. The stabilizer defines a line of maximum thickness that corresponds to the thickest cross sectional portion of the stabilizer along the span-wise length of the stabilizer. The line of maximum thickness is closer to the leading edge of the stabilizer proximate the root portion than at the tip portion, resulting in a pressure distribution that draws higher velocity air away from an inlet of the boundary layer ingestion fan.

Provided is an airflow control system for controlling airflow flowing over an upper surface of an aircraft. The airflow control system includes: a blowout port that is provided on a forward side of the upper surface of the aircraft to blow out the airflow; a suction port that is provided closer to the forward side than the blowout port to suck outside air; a fan that is provided on a rearward side of the blowout port to suck air flowing from a forward side and to discharge the air to a rearward side; and a compressor that is provided in a channel extending from the suction port to the blowout port to increase pressure of the outside air sucked from the suction port and to pressure-feed the resulting outside air to the blowout port.

A hybrid aircraft propulsion system. The system comprises a gas turbine engine comprising a compressor, a combustor, one or more turbines, a shaft coupled to one of the turbines, and a bypass fan mechanically driven by the shaft. The system further comprises an electrical generator mechanically coupled to the shaft, and an auxiliary propulsor mechanically coupled to an electric motor and electrically coupled to the electric generator. At maximum power, the gas turbine engine is configured to produce a turbine entry temperature at maximum power between 1800 Kelvin and 2000 Kelvin, the engine comprises a fan bypass ratio of between 4:1 and 13:1, and the generator is configured to absorb between 10% and 60% of the mechanical power generated by the turbine.

A cross flow fan to be incorporated into an aircraft fuselage comprises an ingestion fan rotor to be positioned in a tail section of an aircraft fuselage to reduce boundary layer air from a top surface of the fuselage and to drive the air away from the top surface, and a drive arrangement for the ingestion fan rotor. An aircraft is also disclosed.