Rich Godwin wrote:


- Refueling the OMS and RCS would be tricky: they run on MMH and N2O4,
hardly the nicest substances to deal with. Fuelling via EVA or via fixed
pipelines on the station each have their own problems.

I know what hypergolics are like. What if we changed the systems to
ambient compressed oxygen & Methane. the ISP is still reasonable and
you could keep them charged more easily and with less degradation of
the system. I realize that you have a criticality ignition failure, so
compress the gases and blow them over an ignition "reed" so that they
ignite on contact.


Now you propose changing the OMS system completely?

What if we just design (and there are enough ideas out there, inside
and outside the Usual Suspect aerospace companies) something *meant* to
be a space tug?



No. Hell, the space station gets refuelled from Progresses (and soon
ATVs) several times a year. But the space shuttle wasn't designed for
it, and adapting the shuttle for refuelling is a tricky problem that's
just not worth the cost.

Depends what you mean by what's worth it!

Do you ever watch 'the Red Green Show?' Some of his ideas
technically do work, but they aren't worth the time and trouble to
produce what can't help but be a sub-optimal design, either...

Do you want something that will do the job well (and with fewer
'miles' on it), or do you want to just prove your MacGuyver-esq cleverness?

--

Frank

You know what to remove to reply...

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