Re: Return To The SSME

On Jan 3, 4:31 pm, Alfred Montestruc <montest...@xxxxxxxxx> wrote:
On Dec 28 2008, 8:41 am, kT <cos...@xxxxxxxxxxxx> wrote:



Brian Gaff wrote:
Just observing all this makes me wonder if anyone actually looked back at
things that occurred before. Seems that the obvious problem of the plume
environment was never considered until far too late, yet it presumably has
been considered in the past  as the smes design was made to cope with close
proximity of engines.

It's a first order 'obvious' engineering consideration, an engineering
'*** test' would have stopped this in committee on the very first day.

1) RS-68 is a massive and inefficient engine compared to the SSME.

2) RS-68 is a fluid hog at startup, and has a well known hydrogen flare..

3) If you want to fly RS-68s, you can fly the Delta IV Medium and Heavy..

If one can simplify the design, why reinvent the wheel, or use a different
whell less well suited to the road, so to speak.

Because Michael Griffin is a fucking idiot engineer. He is incompetent.
Clearly this idiotic idea was originally rammed through the committee.

Who would be in any position to do such a thing? Michael Griffin!

One thing does worry me though. Short termism. OK so the engines might work
out to be cheaper if the Shuttle carries on a bit longer and the political
decisions of  keeping workers is in there, but does this mean that the long
term cost of a program which is supposed to go on far a long time is sound?
 Sounds like someone out in the future could say this is far too costly.

Someone in the past already commented on the engineering failure of it.

The only reason I was enthusiastic about it was the fact that they were
going to use hydrogen, they were going to build a ten meter tank, and
that tank could be reengined with SSMEs, which with the addition of the
SRBs, would easily be capable of delivering that core stage to orbit.

I commented on this way back in early 2006 when it was first proposed.

The problem still remains :

1) the foam insulation.

2) the expendability of it.

Expendability is easily solve. Deliver the core stage to orbit where the
engines can be recovered and gigantic spaceships can be constructed.

The foam problems still remain as the fundamental engineering science of
rocket science, something America has abandoned with Michael Griffin.

Ya know, if the SSME is such a hot rocket engine design, and not
counting upgrades it is over 20 years old, why not outsource
manufacture of it to the Russians?  It is not like they have a
shortage of rocket engines that they could lob ICBMs at us with, so I
do not see a real national security issue.

I bet they could make it a bunch cheaper than we can.

Also the foam insulation is a non-issue for a top mounted spacecraft
as others have pointed out.

Via mass production, China or India could likely accomplish SSMEs at
half if not a third of any Russian cost. Now we're down to a tenth of
any NASA/US produced SSME.

~ BG
.

Quantcast