A Brayton cycle engine and method for operation. The engine includes an inner wall assembly and an upstream wall assembly each extended from a longitudinal wall into a gas flowpath. An actuator adjusts a depth of the detonation combustion region into the gas flowpath between the inner wall assembly and the upstream wall assembly. The engine flows an oxidizer through the gas flowpath and the inner wall captures a portion of the oxidizer. The engine further adjusts the captured flow of oxidizer via the upstream wall and flows a first flow of fuel to the captured flow of oxidizer to produce rotating detonation gases. The engine flows the detonation gases downstream and to mix with the flow of oxidizer, and flows and burns a second flow of fuel to the detonation gases/oxidizer mixture to produce thrust.

A Brayton cycle engine and method for operation. The engine includes an inner wall assembly and an upstream wall assembly each extended from a longitudinal wall into a gas flowpath. An actuator adjusts a depth of the detonation combustion region into the gas flowpath between the inner wall assembly and the upstream wall assembly. The engine flows an oxidizer through the gas flowpath and the inner wall captures a portion of the oxidizer. The engine further adjusts the captured flow of oxidizer via the upstream wall and flows a first flow of fuel to the captured flow of oxidizer to produce rotating detonation gases. The engine flows the detonation gases downstream and to mix with the flow of oxidizer, and flows and burns a second flow of fuel to the detonation gases/oxidizer mixture to produce thrust.

An air-breathing turbojet engine for a hypersonic vehicle is shown. The engine comprises a pump for pumping a cryogenic fuel, an inlet configured to compress inlet air by one or more shocks, a cooler to cool the compressed inlet air using the cryogenic fuel, and a turbo-compressor to compress the air further. A precooler cools the compressed inlet air using compressed cooled air from the turbo-compressor. A combustor receives compressed cooled air from the turbo-compressor and a first portion of the cryogenic fuel for combustion. A first turbine expands and is driven by combustion products, and a second turbine expands and is driven by a second portion of the cryogenic fuel. The first turbine and the second turbine drive the turbo-compressor via a shaft. An afterburner receives combustion products from the first turbine and the second portion of the cryogenic fuel from the second turbine for combustion therein.

A ram air turbine is presented that includes a turbine having a blade and a turbine shaft, a strut removably coupled to the turbine, wherein the strut has a gearbox section and a drive section, a turbine shaft with a bevel gear oriented perpendicularly to the turbine shaft and positioned within the gearbox section of the strut, a driveshaft coupled to the generator and positioned within the drive section of the strut, and a pinion gear that engages with the bevel gear, wherein the pinion gear is secured to the driveshaft by a spanner nut, wherein the pinion gear utilizes a key configured to interact with the keyed joint of the driveshaft. The pinion gear is supported by a pinion bearing that may be press fit onto the pinion gear and by one of the generator bearings.

A ram air turbine is presented that includes a turbine having a blade and a turbine shaft, a strut removably coupled to the turbine, wherein the strut has a gearbox section and a drive section, a turbine shaft with a bevel gear oriented perpendicularly to the turbine shaft and positioned within the gearbox section of the strut, a driveshaft coupled to the generator and positioned within the drive section of the strut, and a pinion gear that engages with the bevel gear, wherein the pinion gear is secured to the driveshaft by a spanner nut, wherein the pinion gear utilizes a key configured to interact with the keyed joint of the driveshaft. The pinion gear is supported by a pinion bearing that may be press fit onto the pinion gear and by one of the generator bearings.

A hybrid propulsion system is provided. The system may comprise a gas turbine engine and a secondary engine, an inlet, an exhaust, a pressurized tank, and an expansion valve. The inlet may be in fluid communication with the ambient environment. The gas turbine engine may have a core passage including a compressor, a combustion chamber, and a turbine. The core passage may be in selective fluid communication with the inlet. The exhaust may be in fluid communication with the ambient environment and the core passage. The pressurized tank may be located upstream of the core passage. The pressurized tank may contain a cooling fluid. The expansion valve may be in fluid communication with the pressurized tank and the core passage. The pressurized tank may provide cooling fluid to the core passage to cool the gas turbine engine during operation of the secondary engine.

A new dual-mode ramjet combustor used for operation over a wide flight Mach number range is described. Subsonic combustion mode is usable to lower flight Mach numbers than current dual-mode scramjets. High speed mode is characterized by supersonic combustion in a free-jet that traverses the subsonic combustion chamber to a variable nozzle throat. Although a variable combustor exit aperture is required, the need for fuel staging to accommodate the combustion process is eliminated. Local heating from shock-boundary-layer interactions on combustor walls is also eliminated.

An inlet arrangement is disclosed herein for use with a supersonic jet engine configured to consume air at a predetermined mass flow rate when the supersonic jet engine is operating at a predetermined power setting and moving at a predetermined Mach speed. The air inlet arrangement includes, but is not limited to, a cowl having a cowl lip and a center body coaxially aligned with the cowl. A protruding portion of the center body extends upstream of the cowl lip for a length greater than a conventional spike length. The protruding portion is configured to divert air flowing over the protruding portion out of a pathway of an inlet to the supersonic jet engine such that a remaining airflow approaching and entering the inlet matches the predetermined mass flow rate.

An inlet arrangement is disclosed herein for use with a supersonic jet engine configured to consume air at a predetermined mass flow rate when the supersonic jet engine is operating at a predetermined power setting and moving at a predetermined Mach speed. The air inlet arrangement includes, but is not limited to, a cowl having a cowl lip and a center body coaxially aligned with the cowl. A protruding portion of the center body extends upstream of the cowl lip for a length greater than a conventional spike length. The protruding portion is configured to divert air flowing over the protruding portion out of a pathway of an inlet to the supersonic jet engine such that a remaining airflow approaching and entering the inlet matches the predetermined mass flow rate.

A dual flow path exhaust assembly for use with a combined turbofan and ramjet engine includes a turbofan engine exhaust duct, a ramjet engine exhaust duct, a combined outlet, and door configured to move between an open position and a closed position to selectively isolate the turbofan engine exhaust duct from the combined outlet.