Re: SSTO - what's the point?

Well, the main problem seems to be that no matter which system you design,
at present, you basically need to be able to lift and accelerate a huge
lump of fuel off the launch pad at the start. In many ways, the Shuttle uses
its solids for this. As the fuel is depleted very quickly, then they are not
needed in quite a short time.

I think this solution is quite alluring, which is, I suspect why they want
to carry on using it.

As has been noted here before, if its crew safety, you are after, a new
orbiter with a detachable crew cabin could probably be built, however, as
this thread is about cost, I'd imagine until we can actually reduce the
weight of propellant needed at the start, you can use whatever you like, but
it ain't gonna be cheap.

You need an engine that will breathe air and be capable of speeds from 0
tomach 4 at least, to be able to cut enough weight to make it cheaper, and
you still have the dead weight issue,unless you throw away your air breather
every time.

Brian

--
Brian Gaff....Note, this account does not accept Bcc: email.
graphics are great, but the blind can't hear them
Email: briang1@xxxxxxxxxxxxxxxx
______________________________________________________________________________________________________________


"John Doe" <jdoe@xxxxxxx> wrote in message news:430FE2A7.DB62B228@xxxxxxxxxx
> re: drymass and dead weight and payload.
>
> One needs to remember that in a fully multi stage rocket, you have dead
> weight at launch time: those engines that will be used only later.
>
> One needs to do math to figure out whether launching greater mass to
> have final stage at lower mass (eg: smaller engines at 100% capacity
> for final stage, but which are dead weight at launch) is better than
> launching at lower mass (no unused engines at launch) but having
> greater mass for final stage of launch (eg: heavier SSMEs not used at
> full capacity for final stage).


.

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