On Fri, 19 Sep 2003, Sander Pool wrote:
> > Correct, but there is no question that capsules are easier and quicker to
> > design and develop.
>
> Sure. But their argument was 'more experience' not "it's easier" :-)
I no longer have the original handy, but my recollection is that it said
"ample experience" or words to that effect, not "more experience".
> > In fact, most satellite owners would really prefer to do final assembly
> > and checkout in orbit, after the bouncy, noisy part is over... but it
> > was difficult to pursue that much with the shuttle.
>
> Could satellite parts be launced separately from the assembly crew?
It's certainly possible, although it adds rendezvous complications. There
have been serious proposals of using multiple launches per comsat -- one
for the bird itself, several for a modular upper stage -- and that was
with a constraint of not wanting to modify the comsats themselves.
> You wouldn't launch the crew until automated processes have confirmed that
> the components survived the launch.
You don't really have the option of automated checkout here -- the whole
point of doing orbital assembly is that the hardware does not have to be
built to 100%-reliably survive launch without a single connection coming
loose. The components are launched in shipping boxes (okay, special
ultra-lightweight shipping boxes), powered down and disconnected.
Besides, that order is backwards. The crew goes up first, because there
is some chance -- however slight -- that if they're on hand first, they
might be able to deal with a problem that would otherwise strand the
components. Which are, to put it bluntly, more expensive than they are.
In fact, it would make sense to have a crew on the component launch.
This is why you have crews on even cargo airliners: the small chance that
they will save an expensive vehicle and an expensive cargo is ample reason
to have them there on every flight.
> Sortof like a smoke test. It would be
> terribly expensive to launch two rockets for 1 payload...
Not necessarily. Particularly if the hardware is reusable, flying a small
vehicle several times can be cheaper than flying a big one once.
> I suppose (day dreaming here) we could build a small space station in an
> appropriate orbit that is specifically designed to support satellite/probe
> deployment. You'd need to launch a lot of satellites for that to make sense
> of course.
Highly desirable, though, because you really want a pressurized hangar
for assembly and checkout.
Henry Spencer
[EMAIL PROTECTED]
_______________________________________________
ERPS-list mailing list
[EMAIL PROTECTED]
http://lists.erps.org/mailman/listinfo/erps-list
