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Old October 20th 17, 12:50 AM posted to sci.space.policy
Fred J. McCall[_3_]
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Default could a shuttle have flown propelled into orbit on a space X booster?

JF Mezei wrote:



since you'd have no fuel for them) the Orbiter weighs over 75 tons.
Falcon 9 maxes out at 25 tons or so to LEO. Even Falcon Heavy can
only lift 70 tons, so it can't boost a Shuttle Orbiter, either.


If the orbiter became an inert part of the vehicle at launch, you could
then remove the 3 SSMEs, saving some 23,000 pounds. That is 11 tons (at
2000 US pounds per US ton).


That's the 75 ton figure I gave; with the engines removed, which was
obvious before you clipped off the front of the paragraph.


That would bring the orbiter (without payload) down to 64 tons, so
within Falcon Heavy's capability.


No, you can't remove the engines twice. The Orbiter is 151,419 lbs at
rollout and 171,000 lbs with main engines installed. In other units,
that's 75.7 tons without engines and 85.5 tons with engines. In other
words, WITHOUT ENGINES the Orbiter is 5.7 tons too heavy for Falcon
Heavy to get it to LEO.


You could lessen weight in the back (no thrust from SSMEs) but would
need to have stronger structures where it attaches to the Falcon Heavy
since those attach points would bear full weight of orbiter during
launch/acceleration.


Note that the weights given for the Orbiter are DRY WEIGHT. If you
want to add things like people and a way to keep them alive, the
weight goes way up. I suppose you could redesign the Orbiter into
being Dragon and that would solve the problem...


And the Falcon Heavy would need redesign so that its attach points to
the shuttle would also be load bearing instead of pushing a payload that
sits on top of it.


So if you redesign the Orbiter so it is something else and you
redesign Falcon Heavy so it is something else you think you could do
it. But you couldn't. You're adding structure which adds dry mass
which reduces payload.

Like I've said before, you should let someone else do the thinking...


--
"Some people get lost in thought because it's such unfamiliar
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