Abstract: A cryogenic fuel tank for retrofitting a conventional fossil-fuel-powered aircraft, or for a purposely built aircraft to run on hydrogen has an aerodynamically shaped outer surface including an ogive shaped nose cone, and a tapered tail cone, wherein the tapered tail cone includes actively adjustable elements for adjusting aerodynamic characteristics of the cryogenic fuel tank. The cryogenic fuel tank is configured to be attached below wings of the aircraft, through support pylons, which include sensors configured to measure forces applied by the cryogenic fuel tank to the airframe. The cryogenic fuel tank includes a nozzle and valve configured to vent gas from the cryogenic fuel tank by expansion through the nozzle in the event that the cryogenic fuel tank is jettisoned from the aircraft.

Abstract: Disclosed is a system for humidifying cabin and/or cockpit air of a fuel cell-powered aircraft system. The system includes a fuel cell stack configured for reacting hydrogen and oxygen to produce electrical energy and a cathode exhaust containing moist, warm air; a water separator configured to cool the moist, warm air and to condense and separate liquid water from the moist, warm air; and a humidifier configured to employ the separated liquid water to humidify pressurized cabin air.

Abstract: Methods and apparatus for cooling a surface on a flight vehicle and generating power include advancing the vehicle at a speed of at least Mach 3 to aerodynamically heat the surface. A first working fluid circulates through a first fluid loop that heats the first working fluid through a first heat intake thermally coupled to the surface and expands the first working fluid in a first thermal engine to generate a first work output. A second fluid loop has a second working fluid that receives heat from the first working fluid and a second thermal engine to generate a second work output. The first and second work outputs are operably coupled to first and second generators, respectively, to power primary or auxiliary systems on the flight vehicle.

Abstract: Methods and apparatus for power generation and/or thermal management on a high speed flight vehicle include circulating a power generation loop working fluid through a power generation loop, which absorbs heat associated with the flight vehicle. A generator operably coupled to the power generation loop generates electrical power. Additionally, a heat transport loop working fluid may circulate through a heat transport loop to provide thermal management through heat transfer.

Abstract: Methods and apparatus for cooling a surface on a flight vehicle and generating power include advancing the vehicle at a speed of at least Mach 3 to aerodynamically heat the surface. A first working fluid circulates through a first fluid loop that heats the first working fluid through a first heat intake thermally coupled to the surface and expands the first working fluid in a first thermal engine to generate a first work output. A second fluid loop has a second working fluid that receives heat from the first working fluid and a second thermal engine to generate a second work output. The first and second work outputs are operably coupled to first and second generators, respectively, to power primary or auxiliary systems on the flight vehicle.