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From: Jeff Greason <jgreason@hughes.net>
Newsgroups: sci.space.policy
Subject: Re: Dan "Critical Path" Goldin Strikes Again!
Date: Thu, 22 Jul 1999 18:17:35 -0700

> > As usual, the more interesting questions are the "why" questions,
> > not the "what" questions.  Why does the SSME need a new nozzle
> > anyway?
>
> What has to be refurbished? Why does that cost so much?

*If* I understand the life limiters on SSME, they're a *long* way
away from where nozzle/chamber life is driving the refurbishment.
Turbopump is a much bigger deal.

>
> Why are we paying for SSME upgrades?
>
> The transportation architecture study showed it was economical to use
> the shuttle for another 20 years!

Yes.  GIGO.

However, I might believe that it's "economical" to use the Shuttle
for 20 years (until a new competitor vehicle comes along -- something
I think is very likely to happen in much less than 20 years).

However, that "economy" is based on the fact that development
costs are already sunk.  Does it still make "economic" sense by
government standards (if there is any such thing) plowing $$ in
for continual upgrades?  This is unclear.

Now, I do know a bit about this nozzle upgrade program, but it's
NDA'd -- so I can't discuss further what the advantages of this
are presumed to be; you'll have to do your own digging on that.
If you do, you can ask yourself whether we're getting our $ worth.

>
>  And if it's
> > cheaper to develop in Russia, why is that?

Because in going to one of the U.S. majors for a program like
this, you are not only paying for the work, and you're not only
paying for the work at *heavily* burdened rates (since these
vendors have significant overhead costs beyond what one might
expect), but you're effectively paying to train a new team.

Something not widely appreciated in the aerospace majors is
that an engineering team is a bit more than a collection of
interchangeable individuals (I'm not the only one who thinks
this is a problem -- check out the article in AvWeek about a
month back on this topic).  So little effort is made to preserve
intact teams.  Combine this with the fact that so little engine
development work has been done in this country in the last 30
years, and every new effort is effectively paying to start
a new company, since the whole team must be rebuilt.  But
even worse -- you don't get to start a new company with all
the advantages of a new company!  You have to instead build
up a new team to do new work operating within the environment
of a large and "post-mature" company.  Ouch!

In Russia, you still have teams of engineers who have developed
rocket engines as a team (this is dispersing, however).  And
you have a lot of hardware for "half-developed" engines which
can be brought to fruition by starting from a point past the
beginning.

That's the real value of the RS-68.  As an engine, it isn't
that impressive -- but its an engine!  That's paid for a lot
of "dusting off" of old work and planting it in new brains.
Whether that team is kept together and kept busy is going to
be a useful tell-tale -- I have my doubts.

Bear in mind my biases -- but I believe rather strongly that
it costs less to develop an engine by starting from scratch
right now than it costs to develop an engine by approaching
the U.S. majors for engine development.  Going to Russia
is an intermediate cost solution, which may approach or
even beat a new start U.S. company if their work can build
on something they've already got partway done (and there
is an *incredible* amount of "partway done" work over
there).

>
> Jeff, I'd like to hear your own answers to your own questions here.
>
Done.

----------------------------------------------------------------
Contact me at                      Jeff Greason
  jgreason at hughes dot net         ex-Propulsion Manager
  (Hughes is my ISP, not employer)   ex-Rotary Rocket


From: Jeff Greason <jgreason@hughes.net>
Newsgroups: sci.space.policy
Subject: Re: Dan "Critical Path" Goldin Strikes Again!
Date: Wed, 21 Jul 1999 14:15:43 -0700

Mike,

  This isn't a "road not taken" by any means.  Channel-wall is one
of the standard ways of doing regenerative cooling.  Brazed tubes are
another.  I don't know whether the Russians or the Americans or the
Germans got to it first, but it's been used so many times in so many
places that there really isn't any case of "developed in the first
place".

  I couldn't care less whether the next SSME nozzle is developed by
Rocketdyne or Energomash with Rocketdyne getting paid for the
integration -- so I have little comment on that front.

"Michael P. Walsh" wrote:
>
> This all sounds as if it is both a lot of concern about very little and an
> ability to read big problems into a rather short news release or
> executive summary.  Doing the development in Russia sounds as
> if it is a reasonable cost-saving way to do business, especially if
> the technology was developed by the Russians in the first place.
>
> The item on the early Aerojet engine is interesting historically, but
> has nothing to do with any current day decisions on building large
> rocket engines.  It might well be another example of a road not
> taken that might have worked out.
>

And later...

> It might be wise to find out if this approach is actually workable
> as a replacement for the current SSME nozzle and then worry
> about avoiding critical paths with the Russians.

It's workable (though there's a lot of tricky details to be
worked out in the integration of the two, I suspect).

As usual, the more interesting questions are the "why" questions,
not the "what" questions.  Why does the SSME need a new nozzle
anyway?  Why are we paying for SSME upgrades?  And if it's
cheaper to develop in Russia, why is that?  (Hint: it's not
because they're paid less!).

----------------------------------------------------------------
Contact me at                      Jeff Greason
  jgreason at hughes dot net         ex-Propulsion Manager
  (Hughes is my ISP, not employer)   ex-Rotary Rocket

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