In sci.space.history Pat Flannery wrote:
On 7/14/2011 11:24 AM, Rick Jones wrote:
http://www.reactionengines.co.uk/sabre.html suggests they are not
actually liquefying the air, only taking it down to the vapor
boundary (whatever that is . They present this as a difference
from previous "LACE" efforts. How much that really changes things
I cannot say.

I still want to know where the nitrogen in the air goes to.

It is used to "nitrogen enrich" the fuel a la Shell and their
commercials?-)

rick jones
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