A hypersonic aircraft includes one or more leading edge assemblies that are designed to manage thermal loads experienced at the leading edges during high speed or hypersonic operation. Specifically, the leading edge assemblies may include an outer wall tapered to a leading edge or stagnation point. The outer wall may define a vapor chamber and a capillary structure within the vapor chamber for circulating a working fluid in either liquid or vapor form to cool the leading edge. In addition, a thermal energy storage reservoir positioned within the vapor chamber contains a phase change material for absorbing thermal energy.

A window installation includes a phase-change filler material sealing an outer edge of the window, and coupling the window to a frame around the window. The filler material in a solid state rigidly holds the window in place. When the filler material is in a liquid state it allows the window to float in its coupling to the frame. There may be supports within the rigid material that contact the window, but allow the window to expand or contract by sliding along the supports. The installation may be useful in situations where the window is subjected to thermal shocks, or other sorts of heating. The installation may be used for a sensor window, and may be part of a hypersonic vehicle.

A window installation includes a phase-change filler material sealing an outer edge of the window, and coupling the window to a frame around the window. The filler material in a solid state rigidly holds the window in place. When the filler material is in a liquid state it allows the window to float in its coupling to the frame. There may be supports within the rigid material that contact the window, but allow the window to expand or contract by sliding along the supports. The installation may be useful in situations where the window is subjected to thermal shocks, or other sorts of heating. The installation may be used for a sensor window, and may be part of a hypersonic vehicle.

In a method of expanding a flight envelope of an aircraft comprising a pair of wing halves and extendable leading-edge flaps at leading wing edges of the wing halves towards higher transonic flight Mach numbers, at least one of the leading-edge flaps at one of the two wing halves is extended in flight direction, when approaching the flight envelope with increasing flight Mach number of the aircraft.

In a method of expanding a flight envelope of an aircraft comprising a pair of wing halves and extendable leading-edge flaps at leading wing edges of the wing halves towards higher transonic flight Mach numbers, at least one of the leading-edge flaps at one of the two wing halves is extended in flight direction, when approaching the flight envelope with increasing flight Mach number of the aircraft.

A sensor system and method of reducing plasma-induced communication inhibition for a main antenna includes using auxiliary antennas for detecting a density of plasma that affects operation of the main antenna, and re-orienting an electromagnetic field around the main antenna in response to the density detected to reduce effect of the plasma on the main antenna. The auxiliary antennas are also operable for data link communication and switchable such if the density of the plasma inhibits receipt or sending of signals by one of the auxiliary antennas, another one of the auxiliary antennas may be used for data link communication.

A fixed wing aircraft has a wing with an aerofoil cross-section defining an upper and lower geometric surfaces which meet at a geometric leading edge of the wing. The wing has an upper and lower aerodynamic surfaces while in flight. The upper aerodynamic surface and the lower aerodynamic surface meet at an aerodynamic leading edge at the intersection with an attachment line dividing the air that passes over the upper aerodynamic surface from the air that passes over the lower aerodynamic surface. The lower geometric surface adjacent the geometric leading edge has a roughness strip with a step height of at least 50 microns over the lower geometric surface. The roughness strip is located on the lower aerodynamic surface of the wing when the aircraft is flown at a load factor of 1 g and is located on the upper aerodynamic surface when the load factor is above 1.2 g.

An aircraft has an empennage and a folding system. The folding system has aerofoils and node bodies which are connected to one another. The aerofoils have at least two nose-side aerofoils and at least two tail-side aerofoils, of which one of the nose-side aerofoils and one of the tail-side aerofoils are port-side aerofoils and one of the nose-side aerofoils and one of the tail-side aerofoils are starboard-side aerofoils. The node bodies have fuselage-side node bodies and outer node bodies. The nose-side aerofoils and tail-side aerofoils are each articulated at a first end to an associated fuselage-side node body, and the nose-side aerofoils and tail-side aerofoils are each articulated at a second end to an outer node body. The tail-side node bodies are displaceable at least partially along an associated translation axis. The folding system functions as the empennage during flight.

A heat exchanger which may be used in an engine, such as a vehicle engine for an aircraft or orbital launch vehicle. is provided. The heat exchanger may be configured as generally drum-shaped with a multitude of spiral sections, each containing numerous small diameter tubes. The spiral sections may spiral inside one another. The heat exchanger may include a support structure with a plurality of mutually axially spaced hoop supports, and may incorporate an intermediate header. The heat exchanger may incorporate recycling of methanol or other antifreeze used to prevent blocking of the heat exchanger due to frost or ice formation.

An air inlet for a flight vehicle engine includes at least one fin, at least partially upstream of a throat of the engine. The fin protrudes into a flow channel, extending beyond a boundary layer into the main airstream in the inlet. The fin causes mixing in the flow, bringing high-momentum flow into areas of the flow channel containing low-momentum flow by aggregating the boundary layer and causing it to lift from the surface. The fin may have a width and/or height that varies along its length in the flow direction, which may allow it to shape the flow around it in predictable ways, without resulting in excessive drag.