Can you get away with a very inefficient turbo-pump?

I think so, but it does need to be compact, so efficiency helps. These a
amazing machines, thousands of horsepower in a very small package.

The regeneratively cooled engine produces waste heat, effectively captured by
vaporization of fuel or oxidizer between turbopump inducer/impeller and
turbopump drive turbine. By running hot, Isp is increased.

Sorry I don't know the efficiency figures.



Yours,

Doug Goncz, Replikon Research, Seven Corners, VA
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