Danny Deger wrote:

"Reunite Gondwanaland (Mary Shafer)" wrote in
message ...
On Sun, 04 Mar 2007 20:46:23 -0600, kT wrote:

However, one can argue that the expendable SSTO approach puts almost an
order of magnitude more mass into orbit, which is what I am suggesting.
Has anyone ever put anything into orbit with a single stage? I know
we've managed SSTS, Single Stage To Space, but I don't think we've
managed SSTO.

I don't think so. SSTO requires engines for efficent than we have and
requires fuel tanks lighter than we have. Both of these technologies need
to be developed to make a SSTO space craft. NASA tried to develop these
technologies a few year ago and failed in both. I don't know if there is
even a concept out there to make SSTO possible.

Er ... no, it should be doable in aluminum and SSMEs. The SSMEs at
propulsive efficiencies in the low to mid 90s is as good as it's gonna
get anytime in the near future. We're years away from full flow staged
combustion. However, there are clear roadmaps to improvement, and thus
SSTO presents no modern breakthroughs, it's just straightforward R&D and
engineering. The necessary structural efficiencies are clearly in the
range of modern materials and modern structural design techniques.

It's when you start adding all kinds of wings and landing gear that
things get iffy, so I propose just starting out with the basics.

I'm shooting for a 35,000 lb. vehicle. Anything more than that and I'll
need GEM-60s, and then the whole thing falls apart rather quickly.

What we really need, a real simple thing : an RL-60.

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