NASA's new focus plan revealed
"Pat Flannery" wrote in message
dakotatelephone...
They might actually be able to do that. When it was designed the RD-170 on
the Energia booster units was built for reuse,so it may be more complex
and robust than it needs to be, as well may be its RD-180 offspring.
It's likely to be "more robust" simply becaue it is a Russian design. The
"more complex" part, I'm not so sure about. If you have an engine like the
RD-180 which is a staged combustion engine which is regeneratively cooled,
there is no fundamental reason that it can't be classified as reusable.
So maybe you can make a expendable one that's simpler and cheaper, sort of
the kerosene/LOX equivalent of the RS-68.
Unless they intend to resurrect the F-1 in some modified form.
True you often can make an expendable version of an engine which is
simplified in some ways, but I have a feeling that what you're really doing
when making an expendable version is tweaking the design so it's easier to
manufacture. If that results in some trade-offs which would otherwise
reduce "reusability", then that trade would likely be made. But there is a
point where shaving margins off an engine makes it less reliable, even for a
single use.
Jeff
--
"Take heart amid the deepening gloom
that your dog is finally getting enough cheese" - Deteriorata - National
Lampoon
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