Space Forum / Shuttle / October 2005

Message from the NASA Administrator Regarding Space Station and Space
Shuttle Comments

Message from the Administrator

I'm sure you've seen the press coverage concerning my supposed comments
on the space shuttle and International Space Station, beginning last
Wednesday.

I've been in Russia since the day the article came out, and have
therefore missed most of the reaction to it, but I've received enough
e-mail to realize that I didn't handle the situation well and have left
some hurt feelings behind. So, I thought I should make the effort to
clarify the situation, and this e-mail to all of you is the best way I
know to do it.

The attention-getting parts of the story were, of course, associated
with the use of words such as "mistake" and "blunder" in connection
with the shuttle and station programs. The press coverage has been such
as to make it appear that I used those words to characterize the
programs. In fact -- and I would hope that this goes without saying --
I did no such thing. I was asked by an interviewer if shuttle had been
"a mistake," and I provided my answer, which addressed the difficulty
of the design challenge and the paucity of funds with which it was
undertaken. This answer was given in the article, and was quoted
correctly. But the use of words such as "mistake" and "blunder," as
well as the overall pejorative tone of the article, was not reflective
of my remarks nor of the general context of the discussion.

At the strategic level, I think all of you know that I believe we have
been restricted to low Earth orbit for far too long and that the proper
focus of our nation's space program should be the exploration of our
solar system. I do understand that others will disagree. In that
context, it is useful to recall Norm Augustine's observation that most
people believe we should have a robust space program; it is just that
no two people agree as to what that program should be! But it is my
sense that this debate has been had and has been resolved for the time
being. The Vision for Space Exploration is the right path, and it is
the path that we are re-engaging our agency to follow. I am committed
to it.

With that said, I do hope you know that I would never speak of our
efforts, past or present, in a way that would be intended to denigrate
the efforts of the engineers, technicians, managers, scientists, and
administrative personnel who "make it happen" at NASA and at our
contractors.

As I have often said publicly, the shuttle is the most amazing machine
humans have ever built, and it has been the recipient of the most
brilliant engineering that America can provide. The station is a more
difficult engineering project, by far, than was Apollo. It is true that
we have not met our original goals for these programs, for myriad
reasons dating back 35 years or more, involving strategic and budgetary
decisions made, properly or otherwise, above NASA. Although this is not
the fault of the dedicated people, past and present, who have worked in
these programs, I think we all know that we can do better, and that we
will. But even if everything were in our favor -- and it is not -- it
would be several years before we could have available a successor to
the shuttle. In the interim, we must complete the station and the only
tool with which we can accomplish that is the shuttle. At this point,
an expeditious but orderly phase-out of the shuttle program, using it
to complete the assembly of the station while we develop a new system,
is the best thing we can do for our agency and for the nation.

These are the messages I have tried to convey. It is not my intention
that they should be used to criticize or diminish the efforts of those
who have devoted their lives -- and in some cases given their lives --
to the space program. Space technology is still in its infancy. To
criticize the shuttle and station because our best efforts have fallen
short of the goals we have set would be like criticizing the early
aviation pioneers because they did not understand, then, how to build
transcontinental aircraft. In this business, our goal is to push the
frontiers of technology, to learn what we can by doing so, and then
move on. And that is what we will do.

Thank you all for your time and attention.

Michael Griffin
NASA Administrator

"tomcat" <jlavine@bellsouth.net> wrote in news:1128379679.087153.206400
@o13g2000cwo.googlegroups.com:

Titanium would not have helped the survivability of the orbiter in a
Columbia-type debris impact. The superheated air that entered Columbia's
wing was probably over 5000 deg F and may have been as hot as 8000 deg F
near the breach. This has been discussed at length in sci.space.* in the
past. One of the better explanations was this one by Henry Spencer:

<http://groups.google.com/group/sci.space.tech/msg/39813114cef4544a?
hl=en&>

(Henry's post also contains some corrections to your misconceptions about
the maximum useful temperature of titanium alloys.)

Also, among several analyses not included in the final report, the CAIB
commissioned a "what-if" analysis of how much longer Columbia's wing
would have survived were it made of titanium. The answer: 13 seconds.
(Hopefully this report will see the light of day in the fourth edition of
Jenkins.) As Henry wrote, this isn't a case of aluminum being "almost"
good enough; there is a huge gap between the highest usable temperature
for a titanium alloy, and the temperatures Columbia experienced inside
the left wing.

You need to stop misusing terminology. The space shuttle is not a
waverider. Waveriders, by definition, have the shock wave *attached* to
the leading edge. The shuttle design goes to considerable trouble to
*avoid* allowing the shock to touch the vehicle at all.

If there's a design flaw in this area of the shuttle, it's not the
aluminum structure or the silica tiles. It's the fragile RCC leading
edges (and the fact that NASA failed to do enough impact tests to
understand just *how* fragile the RCC is) placed in proximity to a
debris-shedding external tank.

As far as I know the tiles have never failed. I have a hard time calling
that a flaw. Over a hundred times those tiles have protected an aluminum
airframe through the dangers you describe above.

There are two things the tiles do. They protect the airframe *and* keep the
interior cool. If you use a higher melting point metal with less insulation
you are going to have to re-engineer internal structures and fluids to
withstand much higher temperatures.

George Evans

"Jon S. Berndt" <jsb.at.hal-pc-dot.org> wrote:

One possibility you seem to have omitted: perhaps the goal (frequent,
reliable, cost-effective access to LEO) was -- and remains -- a lot
harder, technically and economically, than any of us likes to admit.

We spent roughly 40% of the cost of Apollo on STS through 1981. My
guess is that the intrinsic difficulty of CATS was at least three
"Apollos' worth" -- and remains in that range today, whether via
alt.space, via Big Aerospace EEEELV, or via some hypothetical NASA
return to the challenge.