From: rbw3q@rayleigh.mech.Virginia.EDU (Brad Whitehurst)
Subject: Re: what the little bird told Henry
Organization: University of Virginia
Date: Mon, 14 Dec 1992 16:19:03 GMT

In article <1gasfqINNkpa@transfer.stratus.com> dswartz@redondo.sw.stratus.com (Dan Swartzendruber) writes:
>In article <ewright.724096589@convex.convex.com> ewright@convex.com (Edward V. Wright) writes:
>>In <1992Dec10.192026.16340@ke4zv.uucp> gary@ke4zv.uucp (Gary Coffman) writes:
>>
>>>They're also heavy as I recall, something you don't need in a SSTO.
>>>I appreciated the summary you gave earlier, Henry. It looks like they
>>>have a better test program planned than what has been outlined here
>>>before. I still think their schedule is extremely optimistic and
>>>success oriented, but we'll see.
>>
>>I'd be curious to know the exact date, sometime in the last 20 years,
>>when "success oriented" became a pejorative phrase.  Yeah, the project
>>is success oriented.  Just like Project Apollo.  The alternative, I
>>guess, is for a project to be "failure oriented."  I like success better.
>
>
>Look, it's pretty clear (at least to me, and going by some other recent
>postings, to other people as well) that Gary has some kind of axe to
>grind against the whole SSTO concept.
>
>Dan S.

	Actually, I feel most of his posts have been fairly
thoughtful.  It is entirely possible to have varying opinions,
technical, political, and economic, about the DC proposals without
having "an axe to grind".  He has brought up some legitimate concerns
about the engineering difficulties of bringing a system like the DC to
fruition.  He is basically a little more skeptical than Allen and
Henry, but is far from ruling it out.  I have to admit to sharing some
of his skepticism about the ease of designing, building, and operating
ANY new space transport.  No matter how optimistic one is, losing
sight of the pitfalls before one while looking at the shining goal
ahead can result in real problems!  
	My cut on the DC is that the X should be tried, but I think
you'll want to get a LOT more info before the Y is built.  I'm really
bummed that people are writing off the X-30 concept also, because it
seems like it will be "too long" to build an operational craft based
on it.  That was the initial error of the NASP project, I think.
Promoting the first X-30 as a "real" space-plane was not a good idea.
We work on SCRAMjet technology (not the actual engines) and can tell
you that there is a lot of work yet to do to really understand the
physics of fluid flow and combustion in that environment.  Unless you
want to spend seriously painful sums making and breaking engines
(these puppies AIN'T easy to test!), we need detailed info on the
physics so that what is built has a higher chance of success.  Even
so, the performance of the first article is likely to disappoint
(ref.: XP-59 Airacomet), so overblowing the first one, like was done
with NASP, is risky to the program as a whole.  I think this lesson
also can and will apply to the DC.
	So, please, let's thrash out details technical and economic,
but leave the rotten tomatoes at home, folks!
-- 

Brad Whitehurst    |   Aerospace Research Lab
rbw3q@Virginia.EDU |   We like it hot...and fast.