Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V11_1/V11_173.TXT

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Subject: SPACE Digest V11 #173

SPACE Digest                                     Volume 11 : Issue 173

Today's Topics:
         Re: SR-71 Record Flight Information
         Re: Another SR-71 comes to NASA Ames-Dryden
              Re: Sandia Railgun
        Re: Resolving Power of Hubble Space Telescope
             Re: Shuttle Escapes
             Re: Shuttle Escapes
            Re: More space station news...
         Re: Another SR-71 comes to NASA Ames-Dryden
     Re: Coilgun on a 747 - supplies to orbit at $20/lb?
           around the world flight attempt
             Re: Getting Drafted
            Re: More space station news...
      Re: NASA Finds Major Flaw in Space Station Design
              Galileo Update - 03/21/90
----------------------------------------------------------------------

Date: 20 Mar 90 19:12:22 GMT
From: zaphod.mps.ohio-state.edu!uwm.edu!csd4.csd.uwm.edu![e-mail]  (Kenneth J Zarda)
Subject: Re: SR-71 Record Flight Information

From what I have read, I would have to say there is another aircraft out there
that the gov't is keeping quiet about. Don't quote me on this, but
I'm pretty sure the aircraft project is called "Aurora". I seem to
remember reading a qoute by Tom Clancy, saying that our "lovely"
gov't is only showing us the first generation of stealth tech. and that
they most likley are building or have a third generation to the
F-117a. The name of the poject comes from a AW&ST I remember reading.
Other than these small pieces of info I am just as much in the dark as you.

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

Date: 20 Mar 90 20:35:11 GMT
From: concertina![e-mail]  (Steve Hix)
Subject: Re: Another SR-71 comes to NASA Ames-Dryden

In article <[e-mail]>, [e-mail] (Henry Spencer) writes:
> In article <[e-mail]> [e-mail] (Mary Shafer (OFV)) writes:
> >And everybody troops back into the building on this beautiful spring
> >day, exhilerated by the flyby.
>
> Followed by the sound of several thousand people elsewhere on the net
> turning green with jealousy... :-[

Microscopically moderated by one person on the net remembering *his*
(only) SR-71 flyby many years ago while in high school.  (Armed Forces Day,
1967, Pt. Mugu, CA.  Two passes.  :} :} )

Mary and Albion had better seats, though.

------------
"...Then anyone who leaves behind him a written manual, and likewise
anyone who receives it, in the belief that such writing will be clear
and certain, must be exceedingly simple-minded..."   Plato, _Phaedrus_

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

Date: 20 Mar 90 17:42:14 GMT
From: pyuxp!pyuxe!nvuxr![e-mail]  (David Lewis)
Subject: Re: Sandia Railgun

In article <[e-mail]>, [e-mail] (Henry Spencer) writes:
> In article <[e-mail]> [e-mail] (Paul Dietz) writes:
> >The Sandia system is a coilgun, aka mass driver...
> A mass driver is a coilgun, or some variant
> thereon, with *recirculating buckets*:  once the payload carrier (aka
> bucket) is up to full velocity, it releases the payload and is then
> decelerated to be re-used.  This reduces the hardware expended to
> zero, which is just what you want for long-term bulk mass launching,
> e.g. for building space colonies.

Hmmm.  So Q:  How do you decelerate the buckets?  Regenerative braking?
It would seem to make sense -- regenerate some fraction of the power
needed for the launching, instead of turning all that kinetic energy
into waste heat.

What's the ratio of bucket mass to launched mass?  Just how much energy
do you need to dump to slow the buckets down?  Maybe I should just go
and find a copy of O'Niell's original paper/book...

--
David G Lewis                    ...!bellcore!nvuxr!deej
    (@ Bellcore Navesink Research & Engineering Center)
            "If this is paradise, I wish I had a lawnmower."

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

Date: 19 Mar 90 08:26:55 GMT
From: samsung!munnari.oz.au!cluster!metro![e-mail]  (Tim Bedding)
Subject: Re: Resolving Power of Hubble Space Telescope

From article <[e-mail]>, by [e-mail] (Daniel Briggs):
>
> ... Dan Fischer mentioned something that caught my
> interest.  He mentions the stationary speckle pattern of the FOC, and
> then talks about a roll deconvolution.  Could we get a few more
> specifics on this technique?
>

Try an article by M. Mueller and G. Weigelt in Astronomy and Astrophysics
(Vol. 175, p. 312, 1987) called "High-resolution astronomical imaging
by roll deconvolution of Space Telescope data".
   The method involves recording images at two different roll angles
(rotation about the optical axis of HST), typically >= 10 degrees.
It assumes the PSF is only rotated, without changing the speckle
fine structure, although they also propose techniques for cases where
this condition is not met.
   Perhaps someone with more time than I (i.e. not a postgrad!) would
care to summarise the article in non-technical language.

Tim Bedding
Dept. of Astrophysics
University of Sydney.
NSW 2006

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

Date: 19 Mar 90 22:52:38 GMT
From: cs.utexas.edu!news-server.csri.toronto.edu!utgpu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: Shuttle Escapes

In article <[e-mail]> [e-mail] (Mary Shafer (OFV)) writes:
>It's my belief, however, that nothing is absolutely safe, particularly
>flight.  If informed people wish to assume the risk, that's their
>right and their decision.  Nobody is forced to fly in the Shuttle,
>nobody is forced to fly in fighters or bombers or airliners.  We're
>all volunteers.  As long as we really understand the risk we're taking,
>what's the problem?

Exactly.  When discussing elaborate and expensive escape systems, one
should remember that ESA's astronauts were opposed to putting *any*
escape system on Hermes -- they considered the risks acceptable and the
mass penalty excessive.
--
MSDOS, abbrev:  Maybe SomeDay |     Henry Spencer at U of Toronto Zoology
an Operating System.          | uunet!attcan!utzoo!henry [e-mail]

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

Date: 20 Mar 90 17:07:11 GMT
From: mcsun!ukc!edcastle![e-mail]  (A J Cunningham)
Subject: Re: Shuttle Escapes

In article <[e-mail]> [e-mail] (Mary Shafer (OFV)) writes:
#nobody is forced to fly in fighters or bombers or airliners.  We're

    Unless of course they are unlucky enough to be drafted. (No :-))
        Tony


--
Tony Cunningham, Edinburgh University Computing Service. [e-mail]

    Yuppies think I'm a wino 'cos I seem to have no class,
    Girls think I'm perverted 'cos I watch them as they pass.

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

Date: 20 Mar 90 22:51:35 GMT
From: zaphod.mps.ohio-state.edu!know!sunshine![e-mail]  (Buckaroo Banzai)
Subject: Re: More space station news...

I haven't read the original NYT article, so forgive if this is a naive
question, but:

Did the account of part failures take into account the varying amounts of
use/inactivity as the space station is built?  I'd expect parts to fail most
when the station is in full, continuous use and less when it's under
construction and partial use.

Or is most of the failure due to vacuum exposure, micrometeors, atomic
oxygen, etc.?  Is the LDEF examination giving any help in what to expect in
this area?

--
--Alan Wexelblat            internet: [e-mail]
Bull Worldwide Information Systems    Usenet: spdcc.com!know!wex
phone: [phone]
    Adapt, adopt, improvise!

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

Date: 21 Mar 90 06:18:32 GMT
From: nsipo.arc.nasa.gov![e-mail]  (Milo S. Medin)
Subject: Re: Another SR-71 comes to NASA Ames-Dryden

In article <[e-mail]> [e-mail] (Alan Hepburn) writes:

>I second the emotion!  How about convincing the powers that be to do the
>same thing up here by NASA-Ames?  Since my place of employment is just
>a stone's throw from the blue cube (okay, a small stone thrown by a very
>strong person!), I'm sure a low level pass like that would impress a lot
>of people!  Just imagine the fun it would be to fly the SR71 around the
>country, turning onto final at each local airport, firing the burners, and
>blasting the windows out of the terminals!  (Sigh...)
>

Ha! Do you know how much flack the Navy gets every year because of noise
and danger associated with the 4th of July air show at Moffett Field?  People
even complain about the U-2 operations!  Personally, I rather enjoy such things,
but the local community really wouldn't put up with it.  They barely let the
Navy get by with basing P-3's here...

My favorite memory was one woman in Sunnyvale who wrote a letter to the
San Jose Mercury News after the airshow who compared the orange flame of
an F-16 on afterburner with the fires of hell.  No doubt she was making a
political point, but I think it's fair to say few such people live in
earshot range of Edwards AFB...

                        Thanks,
                           Milo

PS Usual disclaimers apply.

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

Date: 18 Mar 90 00:54:08 GMT
From: crdgw1!sixhub![e-mail]  (Wm E. Davidsen Jr)
Subject: Re: Coilgun on a 747 - supplies to orbit at $20/lb?

In article <[e-mail]> [e-mail] (Norman C. Kluksdahl) writes:

| Sure.  You want to fly a 747 that has 25 tons shift by 20 feet?
| Does the phrase "death wish" mean anything to you?

  There are other airplanes. Some of the military cargo planes which
carry tanks can drop them via parachute. What does that do to the CG
when the tank drives from one end to the other and falls out?

  My guess is that something other than a 747 would be a better fit, and
one of the cargo planes designed for CG shift and operation with the
tail open might be a starting point. How about a telescoping launcher?

| No doubt such an arrangement would shatter every conceivable limit
| on the CG limits of the aircraft.  Plus, you have to consider that
| the force necessary to stop about 25 metric tons has to come from
| the aircraft.

  Given that we have planes which are designed for other conditions than
a 747, your objection are correct but not damning. Until I can get
better info on something like a C130 I won't claim that it can be done,
just that the 747 isn't the best choice for proof of concept.

  Even if the payload were limited to 200lb or so, I suspect that if the
cost were something like $20/lb there would be lines waiting for
launches. Even considering the G force, and if a telescoping gun could
be used it might be a lot less, there are useful things to put in orbit.
--
bill davidsen - [e-mail] (uunet!crdgw1!sixhub!davidsen)
    sysop *IX BBS and Public Access UNIX
    moderator of comp.binaries.ibm.pc
"Getting old is bad, but it beats the hell out of the alternative" -anon

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

Date: 21 Mar 90 17:00:39 GMT
From: cs.utexas.edu!samsung!zaphod.mps.ohio-state.edu!sol.ctr.columbia.edu!IDA.ORG!pbs![e-mail]
Subject: around the world flight attempt

(This really should be in the military news group, but 3 attempts to post it
there have failed.)
    On 10 May 1948 three B-29's from the 93rd Bomb Group, 15th Air Force, took
off from Castle Field, California on what was to have been an around the world
flight.  By 19 May they were sitting on the runway at Furstenfeldbruck,
Germany.  Permission to proceed had been withdrawn because of renewed fighting
in the Middle East.  Instead these 93rd BG aircraft retraced their steps home.
Does anyone out there have information about the particular B-29's and crews
involved in this aborted attempt to circle the globe in may of 1948?

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

Date: 21 Mar 90 22:38:14 GMT
From: concertina![e-mail]  (Steve Hix)
Subject: Re: Getting Drafted

In article <[e-mail]>, [e-mail] (A J Cunningham) writes:
> In-Reply-To: Mary Shafer (OFV's message of 20 Mar 90 18:45:30 GMT
> > The Air Force, Navy, and Marines did NOT draft people.  Army troops
> > (who may have been drafted) rode in helicopters flown by pilots who
> > had volunteered.  (Yes, this latter is hair-splitting.)  Even in World
> > War II, all air crew were volunteers.
>
>     Well plenty of Army personnel were herded into gliders for
> Airborne assaults (e.g. Operation Overlord, Operation Market Garden). I
> doubt if that meny of them were volunteers.

Those troops weren't aircrew, though, they were cargo.  The troops dropped
or flown in by gliders during Overlord and Market Garden *were* volunteers,
considering the units they belonged to.  (U.S. 82nd and 101st, British
Red Devils, etc.)

Airborne troops, btw, are almost without exception (certainly during WWII)
tended to be volunteers.  You wouldn't have been drafted into Airborne or
Rangers, for example, but would have had to work hard to make the grade.
The ones whou couldn't make the cut, or didn't want to try, got to ride
around in trucks and other lesser transport.

------------
"...Then anyone who leaves behind him a written manual, and likewise
anyone who receives it, in the belief that such writing will be clear
and certain, must be exceedingly simple-minded..."   Plato, _Phaedrus_

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

Date: 21 Mar 90 17:47:40 GMT
From: idacrd![e-mail]  (Robert McGwier)
Subject: Re: More space station news...

From article <[e-mail]>, by [e-mail] (Mark Earnshaw):
> In article <[e-mail]> [e-mail] writes:
>
> [Description of how Freedom will "fall apart" before it is finished]
>
> I give up.  Why don't we contract Freedom out to the Soviets?  At least we
> know their design works.
>
> Mark Earnshaw



You obviously don't read very much.  The SOVIETS are ALSO reporting that
their cosmonauts are spending huge amounts over the alloted time for
maintenance as everything in sight breaks down.  They have to live in
the same environment FREEDOM will.  Is FREEDOM meant to `counter'
MIR which means peace/world?

Bob

--
____________________________________________________________________________
    My opinions are my own no matter    |    Robert W. McGwier, N4HY
    who I work for! ;-)            |    CCR, AMSAT, etc.
----------------------------------------------------------------------------

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

Date: 21 Mar 90 20:55:32 GMT
From: rochester![e-mail]  (Paul Dietz)
Subject: Re: NASA Finds Major Flaw in Space Station Design

In article <[e-mail]> [e-mail] (Tim Maroney) writes:
>In article <[e-mail]> [e-mail]
>(Paul Dietz) writes:
>>Yesterday's (3/19) NY Times reports that a NASA special
>>investigation team has concluded that the space station, as
>>currently designed, would require 2,200 hours of EVA per year
>>for repairs and preventive maintenance.  This figure, which amounts
>>to about 2 EVAs per week, is described as "alarmingly high";
>>an acceptable rate would be one per month.
>
>Two EVAs per week at 20+ hours per EVA?  Eh?

I screwed up; it's > 3 per week (with > 1 person, I think; the figure
is 2,200 person-hours).  About an order of magnitude too much.

    Paul

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

Date: 21 Mar 90 21:21:47 GMT
From: usc!elroy.jpl.nasa.gov!jato!mars.jpl.nasa.gov![e-mail]  (Ron Baalke)
Subject: Galileo Update - 03/21/90



                     GALILEO MISSION STATUS
                         March 21, 1990

     Today the Galileo spacecraft is more than 68 million miles
from Earth, with a round-trip light time of 12 minutes 14 seconds.
It is almost 69.5 million miles from the Sun, going 86,026 miles
per hour in solar orbit.  The spacecraft has now logged almost
271 million miles in space since launch; it has 376 million to go
to its next gravity assist, at Earth in December, and more than 2
billion miles to go to its destination, Jupiter in late 1995.

     The health of the spacecraft continues to be excellent and its
cruise-mode activity level is relatively quiet.  Galileo is spinning
at 3.15 rmp and all general thermal control temperatures are within
acceptable ranges. Tomorrow, the Venus-Earth (VE-2) sequence will be
loaded to the spacecraft and will go active on March 26.


 Ron Baalke                       |    [e-mail]
 Jet Propulsion Lab  M/S 301-355  |    [e-mail]
 4800 Oak Grove Dr.               |
 Pasadena, CA 91109               |

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

End of SPACE Digest V11 #173
*******************