Editing Liquid air cycle engine (section)

==History==

LACE was studied to some extent in the [[United States|United States of America]] during the late 1950s and early 1960s, where it was seen as a "natural" fit for a winged spacecraft project known as the [[Aerospaceplane]]. At the time the concept was known as LACES, for ''Liquid Air Collection Engine System''. The liquified air and some of the hydrogen is then pumped directly into the engine for burning.

When it was demonstrated that it was relatively easy to separate the oxygen from the other components of air, mostly nitrogen and carbon dioxide, a new concept emerged as ACES for ''Air Collection and Enrichment System''. This leaves the problem of what to do with the leftover gasses. ACES injected the nitrogen into a [[ramjet]] engine, using it as additional [[working fluid]] while the engine was running on air and the liquid oxygen was being stored. As the aircraft climbed and the atmosphere thinned, the lack of air was offset by increasing the flow of oxygen from the tanks. This makes ACES an ejector ramjet (or ramrocket) as opposed to the pure rocket LACE design.

Both [[Marquardt Corporation]] and [[General Dynamics]] were involved in the LACES research. However, as [[NASA]] moved to ballistic capsules during [[Project Mercury]], funding for research into winged vehicles slowly disappeared, and ACES along with it.