Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V15_5/V15NO503.TXT

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Date: Fri,  4 Dec 92 09:55:13
From: Space Digest maintainer <[e-mail]>
Reply-To: [e-mail]
Subject: Space Digest V15 #503
To: Space Digest Readers
Precedence: bulk


Space Digest                Fri,  4 Dec 92       Volume 15 : Issue 503

Today's Topics:
          Adventures in Indianapolis (was Re: Town Meeting)
                         DC costs and markets
           Goldin's vision for NASA (was Re: Town Meeting)
     Higgins & Goldin, eyeball to eyeball (was Re: Town Meeting)
                           Hubble's mirror
         Rush Limbaugh says problems with HST are a DoD hoax!
                           shuttle downtime
                         Shuttle replacement
           Terminal Velocity of DCX? (was Re: Shuttle ...)
                           total power loss

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Date: 3 Dec 92 16:18:09 -0600
From: Bill Higgins-- Beam Jockey <[e-mail]>
Subject: Adventures in Indianapolis (was Re: Town Meeting)
Newsgroups: sci.space,talk.politics.space

[Since this and its two companion articles failed to show up on many nodes,
I've been requested to re-post them.  Sorry if you see it twice.]

In article <[e-mail]>, [e-mail] (John Roberts) writes:
>
> I just saw the midnight NASA Select replay of the Indianapolis Town Meeting.
[...]
>The meeting went very well, at least until some maniac (didn't quite catch
>the name - Huggins, or some such) totally disrupted the proceedings by asking
>some tough questions on DCX and other subjects. :-) :-)
>
>I'd better let Bill comment on the reply. (If he wants, I can extract a
>transcript of the question and the answer.)

John did indeed create a transcript, and I'm posting it as a separate
message.

If you saw the tape you may be asking yourself:  "Why did Bill ask a
rambling, incoherent question, when he *knows* a tightly focused
question (say about DC-X) would have been more effective in
enlightening the audience and creating an impression on NASA?"

The answer is that before the meeting started, I'd talked to a few
Indianapolis people who are active with the National Space Society
and the Midwest Space Development Conference.  Frank Drumwright,
chairman of the 1993 MSDC, was there (to be held in Indianapolis next
22 October, *plug plug*), as were Randy Porter and Barry
Childs-Hilton.   We knew that we each had *many* questions to ask, but
would only get an opportunity to ask *one*.  So we agreed to split up
major topics such as SSTO, space resources, etc.

When Dr. Goldin's presentation ended and the question period started,
I was fifth or sixth to line up behind the port microphone, and my
pals were several people behind me-- like tenth or twelfth.  There was
an equally long line at the starboard microphone in the other aisle of
the theater.  I stood with my clipboard (what a nerd) taking notes on
the questions other people were asking, gradually getting closer to
the mike, and trying to formulate my own question.

At first I thought I would ask about extraterrestrial resources,
especially from asteroids-- I've been doing a lot of reading on this
lately, and I think it's worth emphasizing.  But Goldin had in his
talk, and in other answers, said the word "asteroids" a lot more
frequently than any NASA official I'd ever heard.  He's obviously
friendly to these ideas already and doesn't need much convincing.

So I decided I should change my question to ask about advanced
technology in NASA.  Technology development has the potential not just
to increase capabilities but also to reduce costs in space, and it
should be a big priority on NASA's list.  Yet programs to develop
advanced propulsion, electric power, surface vehicles, better
spacesuits, closed life support, and fancier robotics seem to be poor
relatives.  As a result NASA does a lot of things in the Nineties the
same way they did in the Sixties.

But as I got nearer the head of the line, I looked behind me and saw
that there were too many people there-- we were running out of time,
and of the space-activist gang, I was gonna be the only one who would
get to ask Goldin a question.  (In a few minutes he would split for
another meeting and his deputies would answer more questions. As it
turned out, I asked the last question.)  So I had to ask the *most
important* question, not *my favorite* question. Well, I favor giving
the Air Force a chance to fly the SSTO, and for Allen Sherzer's
campaign promoting this, I think it's important that the NASA guys
hear SSTO questions everywhere they go in the country.

[Not the opinion of Fermi National Accelerator Laboratory, the
Department of Energy, Universities Research Association, or the 49th
Ward Regular Science Fiction Organization.]

This is what led to my trying to cram a whole bunch of points into a
single question.  I neede to ask about SSTO, but didn't want to give
up completely on the other points.  The common theme was that there
were several approaches to reducing costs in space and hence getting
more value for our NASA tax dollars:  ET resources is one, better
technology is another, and lowering launch costs is a third.

Goldin patiently addressed my points (he thought I was talking about
off-the-shelf commercial technology, but I didn't bother to correct
him).  As for SSTO, he gave the same skeptical beware-of-paper-rockets
lecture I've given to other people, saying that DC-X flights were only
slightly relevant to the question of building an operational orbital
launcher, and mentioned "the camel's nose" where a small program
sneaks in and becomes a large program.  But he ended his discourse by
looking me in the eye and saying, "if they come up with something, *of
course* NASA's going to use it," which is more encouragement than I
expected.

John Roberts also writes:

>If it's of any interest, Miss Berkhauser's question and the answer took
>3 minutes 30 seconds, your question took 2 minutes 10 seconds, and the
>answer took 6 minutes 40 seconds.

Getting nearly seven minutes' worth of answer from NASA's top official
is doing pretty well-- and made me feel much better about driving all
the way from Chicago to attend what was essentially a PR event.
Fortunately, in the second half of the forum, after Goldin had left,
my friends all got a chance to question the other NASA officials,
including Col. Charles Bolden, Dr. Wes Huntress, and Marty Kress.

The afternoon reinforced the good impression I'd gotten about Goldin
from the press.  He really does believe in many of the Right Things,
such as faster programs, exploring exterrestrial resources, getting
more science done for the same money, etc.  An acquaintance on the
NASA staff of the meeting suggested that it might be a good idea to
drop a note to Mr. Clinton urging him to keep Goldin (who is a
Democrat) in the new administration.  Hmm.

Bill Higgins, Beam Jockey         | "I'm gonna keep on writing songs
Fermilab                          | until I write the song
Bitnet:      [e-mail]  | that makes the guys in Detroit
Internet:  [e-mail]  | who draw the cars
SPAN/Hepnet:      43011::HIGGINS  | put tailfins on 'em again."
                                            --John Prine
--
     O~~*           /_) ' / /   /_/ '  ,   ,  ' ,_  _           \|/
   - ~ -~~~~~~~~~~~/_) / / /   / / / (_) (_) / / / _\~~~~~~~~~~~zap!
 /       \                          (_) (_)                    / | \
 |       |     Bill Higgins   Fermi National Accelerator Laboratory
 \       /     Bitnet:     [e-mail]
   -   -       Internet:  [e-mail]
     ~         SPAN/Hepnet:      43011::HIGGINS

------------------------------

Date: 3 Dec 92 23:52:24 GMT
From: Henry Spencer <[e-mail]>
Subject: DC costs and markets
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Gary Coffman) writes:
>>>... My question is whether any space launch system can accumulate
>>>enough [flight-test] flight hours to make any of this analysis meaningful.
>>If a jet fighter can, it should be possible with a DC-1.
>
>Jet fighters don't cost $10 million a flight...

I don't see why DC-1 should either.  If DC-X/Y successfully demonstrate
fast turnaround with low refurbishment, the situation should be similar
to early testing of a jet fighter:  the cost of flights is fuel plus
pilot time plus a modest maintenance load.  Fuel is tens of thousands
of dollars per flight, assuming full tanks (some, perhaps most, tests
would not need to achieve orbit), and pilot time cost is minor.  The big
unknown is maintenance.

Maintenance costs usually are dominated by time cost rather than parts
cost.  The crucial number is MMH/FH, maintenance man-hours per flight hour.
I don't know what the numbers look like early in flight test, but an
MMH/FH exceeding 100 in operational service indicates a badly troubled
aircraft, typically an old one kept in service beyond the time when it
should have been replaced.  Arbitrarily add a factor of five for earliness
and another factor of five for more highly stressed parts (although most
DC-1 parts will see stresses no worse than on an airliner).  How many
flight hours per flight?  Most of the hardware works for only fifteen
minutes or so per flight, although life support and electronics have
to be live throughout; let's call it one hour, which is conservative
when you include a lot of short suborbital test hops.  Figuring manpower
at $25/hr, that's $62500/flight.

Add it all up and we're looking at maybe $100k per flight, dominated by
maintenance manpower.  A hundred test flights is no problem; a thousand
would be affordable in an airliner-like development budget.

Of course, if you assume that DC-X/Y will fail in their turnaround
objectives, then you can concoct an arbitrarily bad value for MMH/FH
and "prove" that extensive testing is infeasible.  In which case,
probably nobody will build DC-1 -- certainly it won't be done as a
commercial venture -- and the point will be moot.

>>If you use a DC as a straight replacement for existing launchers, sure.
>>But there is no real requirement to replace existing launchers.  The whole
>>point of building something radically different, e.g. the DCs, is to try
>>to open up new markets...
>
>I agree that there is no real requirement to replace existing launchers...
>... There should be an identified market for this proposed
>spaceship before it is built. That's just good business sense.


Note that I didn't say there was no market; I said there was no requirement
to replace existing launchers.  The existing launchers satisfy existing
markets reasonably well... but there is general agreement that the
existing situation is grossly unsatisfactory, with high launch costs
and high payload costs cooperating to drive each other up and up and up.

There are plenty of identified markets for cheaper space transport; the
problem is that they are all highly speculative until that cheap transport
looks real and people can make plans based on it.  If you want an example,
space tourism at $50k/person is an established market:  Society Expeditions
got lots of bookings at that price, back when Hudson still hoped to build
Phoenix.  Can you make money at that price?  At $10M/flight, no; at $100k,
it shouldn't be hard.

>I haven't seen any mention of customers lining up to buy these spaceships.
>Airliners aren't normally built without firm orders in hand...

That's why nobody is building DC-1s today.  The problem is not finding
people who are interested; the problem is establishing that the initial
investment will result in a working spaceship.  Until there is proof of
principle, no potential customer is going to bet lots of money on the
assumption that a radical departure from existing practice is feasible.
Especially when NASA assures them that it's not.

>money going into this program seems to be coming from the US taxpayer.
>I don't find that evil, as Allen normally does, but it isn't the way
>commercial development is done.

Nobody has claimed that DC-X and DC-Y are commercial developments.  They
are X-planes, in the long tradition of technical pioneering by government
R&D agencies... a tradition that commercial aviation development is firmly
based on.  Some think that the lack of comparable progress in spaceflight
and the lack of a comparable R&D program are not unrelated.
--
MS-DOS is the OS/360 of the 1980s.      | Henry Spencer @ U of Toronto Zoology
              -Hal W. Hardenbergh (1985)|  [e-mail]  utzoo!henry

------------------------------

Date: 3 Dec 92 16:19:04 -0600
From: Bill Higgins-- Beam Jockey <[e-mail]>
Subject: Goldin's vision for NASA (was Re: Town Meeting)
Newsgroups: sci.space,talk.politics.space

[Since this and its two companion articles failed to show up on many nodes,
I've been requested to re-post them.  Sorry if you see it twice.]

I attended the NASA Town Meeting in Indianapolis on 20 November.
After Dr. Daniel Goldin gave his presentation, he took questions from
the audience.  Just ahead of me in line was Emily Berkhauser.  She
asked what NASA expected to be doing in 20 years when she's working
there.

Goldin sketched out a very eloquent picture that gives you a good
summary of his personal vision of spaceflight.  I thought it was
interesting enough that I asked John Roberts to transcribe it from the
videotape he made (the meeting was broadcast on NASA Select).  Thanks,
John, for typing it all in!
======================================

Q: Hi, I'm Emily Berkhauser, I'm 14 years old, I'm a Sophomore, at a
school here in town, and ever since I was little, I wanted to become
an astronaut. I was wondering if you could tell me what is going to go
on in NASA in the next 20 years as far as retirement of the Shuttle
fleet and the possible bringing in of the National Aerospace Plane. I
know that's been discussed.

A: Well, let me tell you a few things that are going to happen, some
of which are going to involve humans, and some are not. Right now, we
don't launch very many spacecraft. I hope 20 years from now, when
you're running one of the major organizations at NASA after you've
gotten an Engineering degree, you get a Doctorate in physics, and
you've become an expert in a field, you do some research, you try to
become an astronaut, you take the test two or three times and you
fail, and you build your inner strength, and you show your toughness,
and you keep coming back and maybe the fifth time you pass the test
and you become an astronaut, and after you've flown in space two or
three times, 20 years from now, we'll be launching spacecraft every
month, maybe every few weeks, but these spacecraft are not going to be
Battlestar Galactica, tens of thousands of pounds, and they won't be
costing billions of dollars, they'll be small spacecraft, weighing
hundreds of pounds, maybe a thousand pounds, with robotics, and
incredible technology in them so they don't have to weigh much or cost
a lot, and instead of costing hundreds of millions to billions,
they'll cost tens of millions to hundreds of millions, and we'll be
sending them out to every planetary body - to planets, to moons, to
asteroids, to comets, to the sun, and we'll be bringing back on a
regular basis samples weighing tens to hundreds of grams, and we'll be
evaluating the samples of all these distant planets to have an
understanding about our solar system.

And about 20 years from now we'll be really getting serious about
building a spacecraft that will go to a near-Earth asteroid. These
near-Earth asteroids take less energy to get to than the moon, and may
be about a mile in diameter. They have the soup from which our solar
system was formed, in rare form there that's not been contaminated by
humans. They may have minerals. Perhaps for your fourth and last
flight you'll be flying to an asteroid - when you're 50 years old you
get there - your hair gets a little grey, and if you're a man you lose
a little bit, but you'll get there. So you may be going to an
asteroid. Or maybe you'll be going to Mars.

And when you go to Mars, the Mars Observer which right now today is
streaking toward Mars, it'll arrive there in August of next year -
that Mars Observer may be finding a landing spot that's logical to go
down. Maybe it'll be at a polar ice cap boundary, maybe it'll be in a
deep canyon, or maybe it'll be near a hydrothermal spot, where you as
the first astronaut to land on Mars might find a fossilized form of
life or discover subsurface water, or discover concentrated mineral
resources so we could build factories on Mars. That's what I foresee
for your future.

======================================

     O~~*           /_) ' / /   /_/ '  ,   ,  ' ,_  _           \|/
   - ~ -~~~~~~~~~~~/_) / / /   / / / (_) (_) / / / _\~~~~~~~~~~~zap!
 /       \                          (_) (_)                    / | \
 |       |     Bill Higgins   Fermi National Accelerator Laboratory
 \       /     Bitnet:     [e-mail]
   -   -       Internet:  [e-mail]
     ~         SPAN/Hepnet:      43011::HIGGINS
--
     O~~*           /_) ' / /   /_/ '  ,   ,  ' ,_  _           \|/
   - ~ -~~~~~~~~~~~/_) / / /   / / / (_) (_) / / / _\~~~~~~~~~~~zap!
 /       \                          (_) (_)                    / | \
 |       |     Bill Higgins   Fermi National Accelerator Laboratory
 \       /     Bitnet:     [e-mail]
   -   -       Internet:  [e-mail]
     ~         SPAN/Hepnet:      43011::HIGGINS

------------------------------

Date: 3 Dec 92 16:20:14 -0600
From: Bill Higgins-- Beam Jockey <[e-mail]>
Subject: Higgins & Goldin, eyeball to eyeball (was Re: Town Meeting)
Newsgroups: sci.space,talk.politics.space

[Since this and its two companion articles failed to show up on many nodes,
I've been requested to re-post them.  Sorry if you see it twice.]

I attended the NASA Town Meeting in Indianapolis on 20 November.
Here is the transcript, thanks to the toils of the industrious John
Roberts, of my questions for Dr. Daniel Goldin, Administrator of NASA,
and his answers.

Sure doesn't read like my usual prose style (which has the benefit of
editing before I post)-- you can almost hear me verbally reaching for
the backspace key.

My mysterious allusion to "Miss Berkhauser" below refers to the
questioner preceding me.  Dr. Goldin expressed the hope that she would
become an astronaut and visit an asteroid.  The complete exchange
between them I will post as a separate message.

Q: Thank you. I'm William Higgins. I'm a physicist, but I'm a
taxpayer, and you're a taxpayer, and to achieve the kinds of visions
that you just described, we need to stretch as far as we possibly can
with the techniques that we have. We want a series of space projects
that we can afford, that we can keep on paying for, that we can
sustain over the years.

There are a lot of angles to attack that problem - one is obviously
developing better technology, and I'm encouraged to hear you talk
about that - I think that NASA hasn't brought as many new technologies
into space capability as we'd like to see, fancy propulsion or
whatever.

Another one is bringing resources in space into play to support space
operations, and I hope that Miss Berkhauser brings back some
propellants that we can use in other space projects from the asteroid
that she visits.

And the third one is very familiar to you I know, and that is launch
costs. It's very expensive to bring something off the surface of the
Earth, and it's always been a fundamental problem of cost in space
flight. At the moment, the Department of Defense is springing a new
launcher off the drawing boards - they hope to fly a prototype next
year  called DC-X, and it's a small version - a small model of course
- of a spacecraft whose full size version might be able to go into
orbit, deploy a payload, and come back and be turned around and fly
again and again, with what they hope is very low operational costs.
It's been reviewed by a lot of people, including NASA internal review,
and they say it'll work - they say it's feasible. I want to know if
NASA will become a customer for such a spacecraft, and what the
climate is for going on from this DoD project to a full-size version
of the "Single Stage To Orbit."

A: You had a lot of thoughts there-- [laughter from audience] Let me
take them one at a time if I can remember them.

Q: I get one shot at the microphone.

A: The first point related to technology. And I think you were
inferring that maybe we shouldn't just use advanced technology, but
where available we should use commercial off-the-shelf technology to
be more cost-effective - Amen verily. We believe that's the right
thing to do. But there's been a psychology sweeping America today,
which says what we've got to do is stick with the technology we have
and productize it as best we can. And I'm worried about  that. And
that gets us to a fundamental issue, and I went to your computational
- are you with this university here?

Q: No.

A: I went to the computational fluid dynamics lab at *your* [pointing
to left side of stage] university, and I met with the professor, and I
was asking him "what are you doing?". Computational fluid dynamics is
a wonderful tool - you're able to operate a jet engine on a computer
instead of building it, so you can understand the design concept. But
in order to do it you need a very fast computer. And unfortunately,
we're not developing advanced chips with real high switching speeds
because it costs too much and it's too risky. That's America we're in
- it costs too much and it's too risky - where's the boldness in
America? So what we're doing as a major portion of our computational
analysis is trying to break it up into little chunks, and we go to
massive parallel processing, which I think is a wonderful approach. So
what this professor was doing was saying "I'm breaking up this
combustion problem into a lot of little pieces, and then I'll operate
it on a lot of little parallel computers, and I'll wrap software
around it so I can have it communicate". I said "Isn't there another
approach? Shouldn't we be bold, and also while we're doing massive
parallel processing, take a look at leapfrog technologies for building
the next generation computer, that perhaps is a billion times faster
than anything we have - there, I said it.

We go two times a year and two times a year and two times a year, and
what's happening is the rest of the world built infrastructure while
we're using our old infrastructure, and surprise surprise - they're
catching up - and what we do in America is measure ourselves on a
relativistic basis - we compare ourselves to other countries instead
of saying "What's the absolute right answer?" Well, if we want to
solve mission to planet Earth, and if we want to build the National
Aerospace Plane, where we don't have a wind tunnel, if we had
computational speeds perhaps nine orders of magnitude greater, because
we were bold enough to think about the next level jump in chip
technology, perhaps we might be in a different place.

So the answer isn't just commercial off-the-shelf technology. The
answer is "America, don't be afraid. Take risks, it's acceptable."
We've become a society that's so risk-averse, we have to spend so much
time making sure it's going to be successful before we move forward
because we're so afraid of failure, that we're paralyzed forever. And
I submit, if we want spacecraft once a month instead of once a decade,
for our planetary program, we could lose three out of twelve
spacecraft every year, and it'll be a rousing success, and we could
take those spacecraft to the cutting edge of technology, feed it back
into America and build an economic furnace that's second to none in
the world. So that's question number one.

Question number two, you referred to the commercialization of space -
I think that's what your intimation was.

Q: Just resource questions.

A: Well, let me tell you. A theoretical problem I proposed to someone
at the Crispus Attucks School [a local grade school]: I said [to a
young man] "Do you want to be a physicist?". He said "That sounds
pretty good". I said "You  know what? We haven't invented a controlled
thermonuclear reaction yet that  uses helium 3... and if we could have
a controlled thermonuclear reaction perhaps 30 years from now with
helium 3, you could have almost no radioactive waste. 25000 pounds a
year of helium 3 could provide all the electricity and all the energy
for America. And maybe 50 years from now or 100 years from now - yes,
we'd have to invest in it today, and we would take a little bit away
from the present, but think about what we could create for the future.
Will it work? - I don't know. And when I say it people say "You can't
say that!". Well, I'm saying it. Now on the moon, because there's no
magnetic field, the helium 3 flows from the sun - this plasma wind has
been writing its signature into the moon for millions of years, and
the moon is rich in helium 3 but the Earth is not. But if we mined
helium 3 from the moon, 25000 pounds is an epsilon - we could bring it
back for almost nothing on a relative basis compared to the trillions
of dollars we spend for energy. There's a possibility. America, don't
be afraid to try controlled thermonuclear reactions! And maybe you
could do it with helium 3 instead of deuterium. All sorts of
possibilities.

Your last question. I'll answer it the same way I answered NASP. What
we have a tendency to do with our space program is spend it on
infrastructure, building infrastructure for decades, getting ready to
spend another few decades building infrastructure. At some point in
time, science and exploration have to dominate our program. You name a
launch system, and there's an advocate for that launch system. NASA
and the DoD have five or six different launch systems. And if we spend
all our money on launch, what are we going to spend on science and
exploration, and we've got to bring our budget into balance.

A lot of promises are being made by a lot of good people. But they're
still lines on pieces of paper and lines on tubes. The experiment
being run does not deal with what you have to do in terms of materials
technology, to do that single stage to orbit job. And some of the
materials problems in that device you're talking about are probably as
difficult or more difficult than some of the problems in the NASP and
the high speed civil transport. So beware of a camel poking its nose
in the tent - now I also say "be bold," so I hope that they work and
are creative, and if they come up with something, *of course* NASA's
going to use it. We are changing - the new NASA doesn't worry about
"not invented here". And if some other organization in this country
comes up with a machine that really is lower cost, we will work with
it. Thank you.

-------------- end of Goldin's question and answer session --------------


     O~~*           /_) ' / /   /_/ '  ,   ,  ' ,_  _           \|/
   - ~ -~~~~~~~~~~~/_) / / /   / / / (_) (_) / / / _\~~~~~~~~~~~zap!
 /       \                          (_) (_)                    / | \
 |       |     Bill Higgins   Fermi National Accelerator Laboratory
 \       /     Bitnet:     [e-mail]
   -   -       Internet:  [e-mail]
     ~         SPAN/Hepnet:      43011::HIGGINS

------------------------------

Date: 3 Dec 92 22:22:04 GMT
From: "William H. Jefferys" <[e-mail]>
Subject: Hubble's mirror
Newsgroups: sci.astro,sci.space

In article <[e-mail]> [e-mail] (Henry Spencer) writes:
#In article <[e-mail]> [e-mail] (William H. Jefferys) writes:
#>
#>By an independent test, I meant a geometric-optics test such as a
#>Hartmann test that could have, fairly cheaply, detected the problem...
#
#Ah, but would it have been believed?  That's the crucial problem.  My
#impression is that it wasn't "we've got three similar tests, and the
#best one says we're okay", but rather "we've got three tests, and the
#best one says we're okay".  The trick was not detecting the error --
#after all, it *was* detected -- but detecting it in a way that would
#have been sufficiently emphatic and unmistakable to make P-E doubt
#their beautiful reflective null corrector.

I can't argue with that! The tests that were performed
lacked "visibility," that is, adequate oversight by people
not involved with the actual testing to ensure that
the anomalies would have been investigated instead of
ignored. At the time, everybody thought the mirror project
was in good shape. People's attentions were directed
elsewhere, because another telescope component was felt
to be at high risk. Thus it was possible for people at a
fairly low level to dismiss the mirror anomalies as inimportant.

#The point of an end-to-end imaging test, in this context, is not that
#it's an easy way to detect the problem, but that it's so hard to
#argue with.

Absolutely correct. And an end-to-end test would have had
"visibility."

Bill

------------------------------

Date: 4 Dec 92 01:38:31 GMT
From: Ryan Korniloff <[e-mail]>
Subject: Rush Limbaugh says problems with HST are a DoD hoax!
Newsgroups: sci.space

The popular American radio personality Rush Limbaugh stated today that the
problems with HSTs mirror are a Department of Defense hoax. He says that
the DoD took over control of the HST program so they could study a strange
radio source that could possibly be another civilization's radio
emmisions. And that the DoD cooked up the story of the faulted mirror to
cover up there actions.
Rush has over 13 million listeners and has may connections into the goings
ons of many behind-the-scenes happenings. I don't think that he would make
such a statment without a reason to believe it is true.
Could some NASA insiders shed some light on this!? This is a rather
radical statement. I have followed the developments closely enough to know
that there is a repair mission due next year and an instrument will be
replaced with COSTAR to correct the mirrir flaw. And what about the
investigations into the contractor who made the mirror? Was NASA wsting
it's time!? This can't be and with 13 million listeners how come nobody
else said anything about this??


        -- Ryan Korniloff
        -- [e-mail]

------------------------------

Date: 3 Dec 92 22:15:09 GMT
From: Henry Spencer <[e-mail]>
Subject: shuttle downtime
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Pat) writes:
>I can't remember, but i thought they needed to requalify either the
>SSME's or the Turbo-pumps.  and that took a significant time period.

They did a top-to-bottom review of the entire Critical Items List, covering
essentially every known failure mode.  That did take a lot of time... but
it could easily have been done after a cautious resumption of flights.

>If the three year down, has helped push down this loss rate then i am all for it

Probably it has reduced the loss rate.  But by *how much*?  There is *no*
limit to how much time and money you could spend making the thing a little
bit safer.  A sense of proportion is necessary; that long downtime did a
lot of damage.  (And most of the safety improvements could have been had
without the lengthy grounding.)

>Henry, you'd be the expert.  has the expected loss rate of orbiters dropped
>due to the system improvements, or is it still sitting at 1/25?

I know what my private consulting statistician :-) (she lives with me) would
say:  "not enough data points".  The post-Challenger upgrades undoubtedly
have improved the situation some:  there are situations which would formerly
have been unsurvivable that the system can now cope with.  But we are far
from having any useful estimate of overall reliability.  The shuttle just
has not flown enough times.

If you're willing to accept data from other programs as indicative, the USAF
figures that large solid rocket motors generally have a 1-2% failure rate,
which would give a shuttle loss rate of 1 in 25-50 (two SRBs, remember) if
everything else was perfectly reliable.  (There is definite evidence that
shuttle landings should not be considered perfectly reliable.)  You might
want to discount that some on the grounds of greater redundancy and more
attention given to the shuttle SRBs in particular.
--
MS-DOS is the OS/360 of the 1980s.      | Henry Spencer @ U of Toronto Zoology
              -Hal W. Hardenbergh (1985)|  [e-mail]  utzoo!henry

------------------------------

Date: 4 Dec 92 01:04:38 GMT
From: Hugh Emberson <[e-mail]>
Subject: Shuttle replacement
Newsgroups: sci.space

>>>>> On Thu, 3 Dec 1992 14:12:59 GMT, [e-mail] (Gary Coffman) said:

Gary> In article <[e-mail]> [e-mail] (Henry Spencer) writes:
[...operating costs of DC-1...]
>If a jet fighter can, it should be possible with a DC-1.

Gary> Jet fighters don't cost $10 million a flight. I don't believe that
Gary> number for a minute, but granting it for this argument, that means
Gary> that a hundred flights would cost $1 billion dollars. The same number
Gary> of flights in a jet fighter costs about $900,000 dollars. Quite a
Gary> difference.

A ordinary jet fighter doesn't cost that much, but how about a SR-71
or a B-2?  Both of those planes are fairly radical, the SR-71 needed
special handling, almost like a space craft.  They are both rare,
which means that parts are expensive and it took (will take) some time
to develop a large knowledge base about them.

I wouldn't be surprised if a DC-1's operating costs are within an
order of magnitude of those of a SR-71 or a B-2.

Hugh




--
Hugh Emberson -- CS Postgrad
[e-mail]

------------------------------

Date: 4 Dec 92 01:40:56 GMT
From: Matthew DeLuca <[e-mail]>
Subject: Terminal Velocity of DCX? (was Re: Shuttle ...)
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Dave Michelson) writes:
>In article <[e-mail]> [e-mail] (Henry Spencer) writes:

>>The FAA, which legally defines "airliner" for purposes of US aviation,
>>reportedly disagrees.

>Details, please, Henry!  Did you see this in AW&ST?

Henry is exaggerating a bit.  The truth of the matter is that when the idea
of certifying the DC-1 as an airliner was proposed to the FAA, they didn't
immediately reject it out of hand.  That's all that has been said on the
matter.
--
Matthew DeLuca             "We should grant power over our affairs only to
Georgia Tech                those who are reluctant to hold it and then only
Information Technology      under conditions that increase the reluctance."
[e-mail]              - Coda of the Bene Gesserit

------------------------------

Date: 3 Dec 92 22:36:05 GMT
From: Henry Spencer <[e-mail]>
Subject: total power loss
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Pat) writes:
>>The fact that no widebody has ever had to ditch at sea shows just how rare
>>total power loss is.
>
>When they certify Twin Jets for commercial passenger flights over oceans,
>they use the acronym ETOPS Extended Twin Engine OPerationS.  Wags
>prefer the acronym Engines Turn Or Passengers Swim...

While I admit to being less than entirely happy with twin-engine operations
over water, especially with the change to ETOPS rules which permits them to
be *three* hours' flying time from a runway, it should be noted that the
old minimum-three-engines rule dated from piston-engine days, when engine
reliability was awful by modern standards.

>Actually how many instances of total power loss have their been?
>The brits lost one after an engine fire on a 757 and the pilot
>then shut down the remaining good engine.  Their was Gimli and
>and an incident when a US airliner lost all engines when a mechanic
>forgot an o-ring on all foour engines.   there was also the avianca?
>(Columbian airline)  that ran out of fuel enroute to JFK.
>Have their been any other isntances?

The Manchester accident was a 737, actually.  There have been several
cases of *transient* loss of all engines in which enough power was
regained to limp to a landing; the Tristar O-ring case was one of them,
and there were at least two others involving 747s flying through volcanic
ash clouds.  The Columbian airliner actually had arrived, but ended up
running out of fuel while waiting to land, mostly because the pilot never
said the magic word "emergency".  (And in the Gimli incident, the pilots
were violating the rules by flying passengers on an aircraft with no
functioning fuel gauges, although this wouldn't have led to a sudden
unexpected quietness if a metric/imperial conversion hadn't confused
refuelling.)
--
MS-DOS is the OS/360 of the 1980s.      | Henry Spencer @ U of Toronto Zoology
              -Hal W. Hardenbergh (1985)|  [e-mail]  utzoo!henry

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End of Space Digest Volume 15 : Issue 503
------------------------------