Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V13_5/V13_537.TXT

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Subject: SPACE Digest V13 #537

SPACE Digest                                     Volume 13 : Issue 537

Today's Topics:
               Re: Saturn V and the ALS
               Re: Saturn V and the ALS
              air-breathing first stages
          Need help displaying a FITS image
              Re: why the space station?
          Hypersonics ... paritcularly Hotol
         [l/m 7/11] Frequently asked SPACE questions
            space news from March 18 AW&ST

Administrivia:

    Submissions to the SPACE Digest/sci.space should be mailed to
  [e-mail].  Other mail, esp. [un]subscription requests,
  should be sent to [e-mail], or, if urgent, to
             [e-mail]

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

Date: 10 May 91 20:12:01 GMT
From: celit![e-mail]  (Dave Smith)
Subject: Re: Saturn V and the ALS

In article <[e-mail]> [e-mail] (Brad Mears) writes:
>Your attitude is very understandable, but you left something out.  How can
>NASA regain the trust of the general public (or even Congress)?

The first step is to admit that NASA makes mistakes.  Instead of going on
and on about how the Space Shuttle really met all of its design goals,
the Agency needs to admit that it did NOT meet many of its design goals.
Examine the reasons why these design goals were not met.  Come up with
a plan that addresses these problems for ALS.  Explain why ALS is a good
idea.  Explain how ALS will be managed in a different manner, not just
"it will be cheap because we said so."

--
David L. Smith
FPS Computing, San Diego        ucsd!celit!dave or [e-mail]
"It was time to stop playing games.  It was time to put on funny hats and
eat ice cream.  Froggie played his oboe" - Richard Scarry

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

Date: 9 May 91 16:00:08 GMT
From: snorkelwacker.mit.edu!usc!rpi!news-server.csri.toronto.edu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: Saturn V and the ALS

In article <[e-mail]> [e-mail] (Brad Mears) writes:
>|> ... Since the track record so far is an expensive launch
>|> system that does not meet promises, it is nearly *impossible* to trust
>|> you again.
>
>Your attitude is very understandable, but you left something out.  How can
>NASA regain the trust of the general public (or even Congress)? ...

By demonstrating that the causes of the Shuttle fiasco are understood and
that major changes have been made in those areas.  Note, you have to actually
make changes, not just claim that things are going to be different this time
because it says so in the specs.

But the onus is on you to prove that things can be different.  In the absence
of specific changes, Congress et al are perfectly justified in assuming that
what happened once is likely to happen again.
--
And the bean-counter replied,           | Henry Spencer @ U of Toronto Zoology
"beans are more important".             |  [e-mail]  utzoo!henry

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

Date: 9 May 91 15:48:30 GMT
From: snorkelwacker.mit.edu!usc!rpi!news-server.csri.toronto.edu!utzoo![e-mail]  (Henry Spencer)
Subject: air-breathing first stages

In article <[e-mail]> [e-mail] (Doug McDonald) writes:
>>A much simpler and cheaper way to get that extra speed and altitude, given
>>ample budget and an absence of other constraints, is just to put another
>>rocket stage under the thing.  It makes little sense to build an aircraft
>>capable of a wide variety of performances including sustained supersonic
>>cruise if all you want is one quick push to high speed and altitude.
>
>The thing I have always wondered is why the bottom stage would not be,
>rather than a rocket, an air-breather...

The idea has its merits, and it's occurred to a number of people.  There
is a small amount of research work being done on it, including some in
Japan.  There is a minor problem in that adding air intakes is another
complex design constraint:  intake design, especially for use over a wide
range of Mach numbers, is not easy.  There is a more serious problem in
that designing engines for use over a wide Mach range isn't easy either:
off-the-shelf engines poop out at Mach 2.5 or so, which is reached very
quickly by a rocket.  And then there is a major problem, the main
reason why the idea hasn't yet flown, in that the thrust:weight ratio of
airbreathing engines is nowhere near as good as rockets.  Fighter engines
currently have T:W of 8-9.  It's a poor rocket engine that doesn't have
T:W of at least 75.  So it's relatively hard to build an airbreathing
stage that can supply a lot of acceleration.

The one reasonably easy air-breathing-assist scheme I know of, I heard
first from Dani Eder, although I don't know if he invented it.  Take a
modern fighter engine, add a small fuel tank, some control equipment,
and a streamlined housing.  Voila, a reusable strap-on booster.  At full
afterburner this thing will contribute quite a bit of thrust.  At Mach
2.5 or so, it throttles back and drops off.  It flies back under remote
control and lands.  No wings; even with the afterburner shut off to
reduce fuel consumption, thrust much exceeds weight and the thing can
fly perfectly well as a VTOL.  It's not going to contribute a huge boost
in performance, but it might be a viable substitute for small expendable
solid strap-ons like Delta uses.
--
And the bean-counter replied,           | Henry Spencer @ U of Toronto Zoology
"beans are more important".             |  [e-mail]  utzoo!henry

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

Date: 29 Apr 91 22:31:56 GMT
From: mcsun!ukc!uos-ee!ee.surrey.ac.uk![e-mail]  (Ata Etemadi)
Subject: Need help displaying a FITS image

Dear all

I have a terrific max-entropy, 3 arc second res., radio image of CasA
which I originally converted to FITS using MIDAS (Munich Image Data
Analysis System). Now I want to convert it to pgm or raw so that I can
view it under X. The problem is its in double format, ie 4 bytes per
pixel. I tried fitstopgm but it didn't like it. Any suggestions...

    regards
        Ata <(|)>.
--
===============================================================================
Dr. A. Etemadi,                           | Phone: [phone] Ext. 2311
V.S.S.P. Group,                           | Fax  : [phone]
Dept. of Electronic and Electrical Eng.,  | Email:
University of Surrey,                     |   Janet: [e-mail]
Guildford,                                |          [e-mail]
Surrey GU2 5XH                            |   SPAN : ata@mssl
United Kingdom                            |          ata@msslc
===============================================================================

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

Date: 9 May 91 16:41:40 GMT
From: mintaka!think.com!rpi!news-server.csri.toronto.edu!utgpu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: why the space station?

In article <[e-mail]> [e-mail] ("JOHN E. PERRY") writes:
>Before the Great Apollo Spectacular, there was a well-reasoned plan
>for American access to space, and we were pursuing it vigorously and
>reasonably. There were a number of articles written about it, and they
>should still be around for anyone who knows how to ferret them out.

Uh, really?  References, please.  I think you're confusing design studies
with plans.  If you look at, for example, the NASA History books on Apollo,
it's fairly clear that before JFK gave the marching orders, NASA had no
clear long-term objectives and precious few short-term ones.  In particular,
there were only the vaguest notions about what might follow Mercury for
manned spaceflight.  Lots of ideas, yes, but no political commitment,
and a general attitude of hostility toward major space spending in both
Congress and the White House.

>All of this was swept out the door in the frenzy to make Kennedy's 1970
>Apollo deadline...   the opinion that there was
>a good chance that we could have made it by 1970 following the original
>concepts, given the huge increases in budgets prompted by Kennedy's deadline.

I don't think you'd have heard anything like that from Wernher von Braun
or Maxime Faget, who were the ones charged with actually doing it.  They
had grave doubts about making the 1970 deadline even on a crash-program
basis.  Notably, von Braun admitted openly and repeatedly that if higher
management had not prevailed on him to do "all up" testing of the Saturn V,
rather than the cautious step-by-step procedures previously followed, the
chances of making the Moon by 1970 would have been zero.  Also notably,
Eagle, which landed six months before the deadline, was the first Lunar
Module actually capable of landing on the Moon (the first flightworthy
ones, flying only a few months earlier, were too heavy), despite tremendous
efforts and vast expenditures.  If there was an easier and cheaper way,
some very competent men missed it completely.
--
And the bean-counter replied,           | Henry Spencer @ U of Toronto Zoology
"beans are more important".             |  [e-mail]  utzoo!henry

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

Date: 9 May 91 08:46:35 GMT
From: mcsun!ukc!dcl-cs!gdt!brispoly!gould2![e-mail]  (Les Carleton)
Subject: Hypersonics ... paritcularly Hotol


I am doing some small research (pleasure more than serious) into the
current state of Hypersonic Transport research. I'm not far into the
subject at the moment, but know of at least 2 projects that exist or
did exist (NASP and Hotol). Can anyone email or post some background
on the current state of these projects (budget/technology/schedules?).

Many Thanks

...Les...
"Whats beyond hypersonic ... megasonic?"

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

Date: 10 May 91 11:01:26 GMT
From: eagle!data.nas.nasa.gov!amelia![e-mail]  (Eugene N. Miya)
Subject: [l/m 7/11] Frequently asked SPACE questions

This list does change.  Slowly.  It only changes when the members
of s.s. have something to add, correct, etc.  I no longer have time to
read s.s., and the SNR is too low.  So if this
does not change it is more a reflection of the other people
you are reading, and not me.  Think about that for a moment.
You make the difference.
    "It's not a message.  I think it's a warning." -- Ripley

This is a list of frequently asked questions on SPACE (which goes back
before 1980).  It is developing.  Good summaries will be accepted
in place of the answers given here.  The point of this is to circulate
existing information, and avoid rehashing old answers.  Better to
build on top than start again.  Nothing more depressing than rehashing
old topics for the 100th time.  References are provided because they
give more complete information than any short generalization.

Questions fall into three basic types:
1) Where do I find some information about space?
Try you local public library first.  You do know how to use a library, don't
you?  Can't tell these days.  The net is not a good place to ask for
general information.  Ask INDIVIDUALS if you must.  There are other sources,
use them, too.  The net is a place for open ended discussion.

2) I have an idea which would improve space flight?
Hope you aren't surprised but 9,999 out of 10,000 have usually been
thought of before.  Again, contact a direct individual source for
evaluation.  NASA fields thousands of these each day.

3) Miscellanous queries.  Sorry, have to take them case by case.

Initially, this message will be automatically posted once per month
and hopefully, we can cut it back to quarterly.  In time questions and
good answers will be added (and maybe removed, nah).

1) What happen to Saturn V plans? What about reviving the Saturn V
as a heavy-lift launcher?

Possible but very expensive -- tools, subcontractors, plans, facilities
are gone or converted for the shuttle, and would need rebuilding,
re-testing, or even total redesign.

2) Where can I learn about space computers: shuttle, programming,
core memories?

%J Communications of the ACM
%V 27
%N 9
%D September 1984
%K Special issue on space [shuttle] computers

%A Myron Kayton
%T Avionics for Manned Spacecraft
%J IEEE Transactions on Aerospace and Electronic Systems
%V 25
%N 6
%D November 1989
%P 786-827

Other various AIAA and IEEE publications.

Computers in Spaceflight: The NASA Experience
James E.  Tomayko
1988?

3) SETI computation articles?

%A D. K. Cullers
%A Ivan R. Linscott
%A Bernard M. Oliver
%T Signal Processing in SETI
%J Communications of the ACM
%V 28
%N 11
%D November 1984
%P 1151-1163
%K CR Categories and Subject Descriptors: D.4.1 [Operating Systems]:
Process Management - concurrency; I.5.4 [Pattern Recognition]:
Applications - signal processing; J.2 [Phsyical Sciences and Engineering]:
astronomy
General Terms: Design
Additional Key Words and Phrases: digital Fourier transforms,
finite impulse-response filters, interstellar communications,
Search for Extra-terrestrial Intelligence, signal detection,
spectrum analysis

You can make it change.  Just discuss the changes on the net, then mail the
resolution to me.

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

Date: 10 May 91 03:47:43 GMT
From: usc!rpi!news-server.csri.toronto.edu!utzoo![e-mail]  (Henry Spencer)
Subject: space news from March 18 AW&ST

[This is the "forecast and inventory" issue, light on current news.]

Editorial suggesting that the best way to sort out US space policy, and
lack thereof, is to substitute the word "purpose" for "policy".

NRC Space Studies Board criticizes current space station design as being
ill-suited for either life-science or materials microgravity work.

Workforce reductions at Reston as station cuts sink in.

DoD re-warms to NASP, saying technical progress has been remarkable and
several military applications for hypersonic cruise are now seen.

Stafford group will strongly back restarting nuclear-rocket programs for
use in Mars exploration.  Both nuclear-thermal and nuclear-electric systems
are of interest, but nuclear-thermal looks most promising for openers:  it
offers a high enough exhaust velocity to make fast trajectories possible,
greatly reducing worries about radiation and free-fall effects, and it has
enough thrust to make far more abort modes available in case of trouble.

The downside of all this is public antinuclear hysteria and its political
effects, very uncertain costs, the possibility that the push for high
performance may lead to exotic designs that worsen development problems
(in particular, sources say "They're doing a lot of evaluation by rocket
people and not enough by nuclear people"), and lack of effort on important
but unglamorous supporting technologies ("either way you go, chemical or
nuclear, you're going to need new ways to store and handle liquid hydrogen...
but what's the funding for cryogenic technology?  Zero!").

The Stafford group reportedly will reject the Augustine commission's open-
ended approach, and urge setting a specific schedule for a return to the
Moon and an expedition to Mars.

First Titan IV launch from Vandenberg March 8, probably carrying a Lacrosse
military radarsat.

Titan IV launch schedule to be cut about 30% during the rest of this decade
due to tight budgets and reduced payload requirements.  One problem is what
effect this will have on the work to convert the Vandenberg shuttle pad to
a Titan IV pad:  the new schedule is probably too busy for one Vandenberg
pad but will come nowhere near full use of two.

Big excitement about tactical missile defence in the aftermath of the Gulf
War:  it now seems indisputable that the missile threat is real, US nuclear
forces cannot deter it, US conventional forces are not good at finding and
destroying missiles before launch, and missiles can be intercepted.  What
sort of hardware this translates into is another question.  SDIO is basically
reshuffling its organization to bring as much of it as possible under the
new hot "tactical" label, but Congress probably won't buy the same old
programs with only the labels new.  One area where real changes are likely
is sensor satellites.  Another is that SDIO has now formally abandoned the
1993 target date for a decision on major SDI deployment; Congress has always
considered this deadline early and arbitrary anyway.

Long overview story on new space-technology efforts.  Current efforts are
pretty small; one of note is a project looking at monitoring rocket-engine
health by optical sensors looking at the exhaust plume, which seems to
have some predictive value and could perhaps detect impending engine failure
ahead of time.  Near-future efforts are planned to emphasize funding for a
small number of major topics:  an advanced space engine to replace the RL-10
oxyhydrogen rocket motor, planetary rover technology, nuclear propulsion,
and life support (particularly radiation protection).

Story about planned upgrades and possible future directions at the Cape.
Current approaches to launcher and payload processing, and current launchers
themselves, are considered inadequate for future activity.  "We've forgotten
that launch vehicles are transportation systems."

Soviet space program facing budget difficulties.  In particular, the future
of the "Mir 2" efforts is now uncertain.
--
And the bean-counter replied,           | Henry Spencer @ U of Toronto Zoology
"beans are more important".             |  [e-mail]  utzoo!henry

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

End of SPACE Digest V13 #537
*******************