Spaceflight

An airborne atmospheric oxygen liquefaction system that would fuel an air-launched vehicle in spaceflight has been awarded more funding by the US Department of Defense.

The $350,000 hardware demonstration contract awarded in April follows a $653,000 award last year to Seattle-based Andrews Space to develop its Alchemist Air Collection and Enrichment System (ACES). ACES would use hydrogen propellant for the air-launched space vehicle, and to produce liquid oxygen on the carrier aircraft by cooling ingested atmospheric air. The hydrogen would be carried by the carrier aircraft, which would itself launch horizontally from a runway.

“We are not talking about fielding an operational system for at least a decade,” says Andrews Space engineering director Eric Wetzel. He emphasises the difficulty of achieving the goals because the technology has not been tested before. Under the 2005 contract Andrews Space demonstrated basic technologies and built a rotating test apparatus for advanced cryogenic testing. ACES was initially assessed by NASA for feasibility and has since been funded by the US Air Force Research Laboratory and Defense Advanced Research Projects Agency.

The US military sees an in-flight fuelled air-launched space vehicle as one route to enabling rapid space launch, satellite deployment and global strike missions.