Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V13_4/V13_447.TXT

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Subject: SPACE Digest V13 #447

SPACE Digest                                     Volume 13 : Issue 447

Today's Topics:
          Re: Government vs. Commercial R&D
            SPACE Digest V13 #444
          Re: Energia (was Re: Saturn V blueprints)
           Sorry, this is a little off the subject
               Re: Saturn V and the ALS
              Saturn V  vs. ALS
              Re: Galileo status reports
                <None>
             Re: R-100 and R-101

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

Date: 24 Apr 91 03:44:09 GMT
From: wuarchive!zaphod.mps.ohio-state.edu!rpi![e-mail]  (Michael V. Kent)
Subject: Re: Government vs. Commercial R&D

In article <[e-mail]> [e-mail] (will) writes:
>    I don't entirly agree with the Anti-trust thing, I mean if America
>    can allow murders to run rabid, crazies to mass murder 10+ people
>    and put them back on the street, allow police officers to beat up
>    people for enjoyment.  I think congress can overlook a simple little
>    thing like Anti-trust.  Besides with half of America on drugs I really
>    don't think anyone is going to notice.  At least this is what is printed
>    in the Japanese news, that an average Japanese will read.
>
>                            Will.....

Gee, and I thought the USSR was a closed society.

--
Michael Kent                                  [e-mail]
McDonnell Douglas                             Rensselaer Polytechnic Institute
St. Louis, Missouri                           Troy, New York
                               Apple II Forever!

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

ReSent-Message-ID: <[e-mail]>
Resent-Date:  Tue, 23 Apr 91 15:25:36 EDT
Resent-From: Tommy Mac <[e-mail]>
Resent-To: [e-mail]
Date:         Tue, 23 Apr 91 02:14:45 EDT
Reply-To: [e-mail]
From: [e-mail]
Subject:      SPACE Digest V13 #444
Comments: To: [e-mail]
To: david polito <[e-mail]>, Tom McWilliams <[e-mail]>

Subject: Re: Laser launchers

>>Then add in the fact that
>>atmospheric blooming will reduce the delivered energy of the beam
>>by a factor of 1000 to 1000000 at high altitudes

>Support this assertion.  What conditions are you assuming?  What
>sort of optical system, etc?  The sun puts ~1KW/m^2 onto the
>California desert, and nobody notices thermal blooming.

So what?  Blooming is a function of energy-density, too.  7 watts/meter-squared
is quite a bit less than what's required for propulsion from the surface!

>An optical system designed to avoid blooming will have many mirrors,
>and mirrors much larger than the target.  This will keep the power
>density much lower than a simplistic system, with one aperture equal
>to the size of the target.

About time!  I've been waiting for someone to point out the many-laser idea.

>>with terrible efficiency. While for a rocket, the longer it runs, the
>>faster it goes since it's mass ratio is continually improving right
>>up until burnout.

>This statement ran my bogosity meter off the scale.  It reflects
>such amazing ignorance or carelessness, one wonders where to begin
>to pick it apart, and whether one should bother.  So I won't.

I'm not sure what a 'bogosity meter' is, but I reckon it's a phrase you draw up
whenever you don't have a real answer.
Point being that what was said about rockets being more efficient in the later
stages of a trip is neither 'ignorant' or 'careless', but rather; QUITE TRUE.
No wonder you won't bother to 'pick it apart'.

>>This is *the* advantage of the laser scheme. If the power stored in
>>those ground mounted tanks could really be delivered to a spacecraft
>>at high altitude with good efficiency, then laser launching would
>>be practical.

>>At the power levels required to loft real payloads
>>into orbit, atmospheric blooming is an intractable physical problem.

>Consider the power level of the solar energy striking the ground,
>and tell me why sunlight isn't an intractable physical problem.
>Now consider the power levels of a laser launch.  What is the
>greatest power density which avoids blooming?  Now, how much
>aperture is required?  Did you ever ask yourself this question?
>If not, shame on you.

Sunlight does bloom, as does starlight, aurora light, light pollution, etc.
Just ask the guys that paid for the hubble scope (since it was supposed to
get, literally, above the blooming problem).
Also, questions which you seemed to have missed are;

At what wavelengths is blooming less of a problem?
What's the best power density at a particular wavlength which does not bloom?
WHat is the altitude/blooming function?

>>Talk to the guys who have actually
>>fired high power lasers, the laser fusion folks, and see what they
>>say about the absolute necessity of having a hard vacuum to fire the
>>beam through.

>I'd prefer that you do sanity checks on your statements before
>posting them.  Imploding fusion pellets is a very different
>problem than vaporizing a layer of a meter-wide target.  It
>takes vastly greater power levels and faster rise times.  The
>pitfalls experienced by the LF workers will not be applicable.

Nonesense.  Of course it will.  Both need to transmit high amounts of energy
via an electromagnetic beam which has been focused on a target of tiny angular
size.  To claim otherwise is to prove the need for sanity checks yourself.

>>Tethers need to exceed the theoretical strength of materials limits by
>>orders of magnitude to work. Again, a fundamental scientific breakthrough,
>>not engineering R&D, needs to occur before tethers can become reality, if
>>ever.

>How many tether studies have you read?  Did you ever read anything
>about non-synchronous tethers, or work any figures yourself?  If
>not, you are talking through your hat.

He may be talking through his hat, but as far as material strengths are
concerned, there is no practical tether material (for lifting from the surface)
His lack of thourough research does not change the fundamental problem.

NOT-SO-STANDARD DISCLAIMER:
I realize that it's somewhat rude to get in the middle of a flame war, and even
encourage it to some extent, but I do have justification;

Rather than pointing out what was incorrect, or providing information to the
other party, you seem to feel it's ok to (try to) insult/belittle someone for
making a factual error or expressing an idea you don't like / disagree with.

Doing this is not only lame in it's own right, and possibly embarrasing for the
perpatrator, but encourange others to do it (like me), which ultimately adds
only hard feelings and hindered communications to the discussion, and takes up
lots of disk space that could be utilized in much better ways.

It's especially worthy of ridicule when you are doing exactly what you are
flaming someone else for doing!
For example, claiming someone is ignorant while being quite ignorant yourself.
Or saying they should read up on something that you're talking through your hat
about, too.
Or calling for sanity checks while invoking irellevant facts.

P.S. maybe I'm wasting space, but I feel that keeping the flak and not-so-
     friendly sparring to a minimum is important.  Especially since, by the
     nature of my abrasive personality, I find it so easy to join in.

     And I just don't have the time.

Flame to;  Tommy Mac
           18084tm@msu
Acknowledge-To: <18084TM@MSU>

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

Date: 23 Apr 91 20:24:00 GMT
From: mentor.cc.purdue.edu!noose.ecn.purdue.edu!en.ecn.purdue.edu![e-mail]  (/dev/null)
Subject: Re: Energia (was Re: Saturn V blueprints)

In article <[e-mail]>, [e-mail] (Doug Mohney) writes:
>
> They need the cash too badly...they'd provide decent services. There's nothing
> which NASA needs to lift into orbit on Energia which couldn't wait a couple of
> years in case of disruption of launch services from the Soviet Union via
> political events.
>
Yeah, but the couple of years disruption might turn into no more launchers
from the USSR, and then where would we be?  No heavy lift vehicle, and
nothing in the pipeline.  Or when we get dependant on them for the space station, what's to keep them from raising prices to soak 'those evil capitalists'
when we really need to keep crew members alive.

No... its a bad idea and I'm sorry I even mentioned it!

I feel much more comfortable with US made space hardware.

Incidentally, to those who feel the USSR wouldn't do that, I'd hasten to point
out the growing power of the 'hardliners' who still denounce us as the root
of their ills, and as  evil capitalists.


--
+-----------------------------------------------------------------------+
| Brent L. Irvine     |            These are MY opinions   |
| Malt Beverage Analyst     |            As if they counted...:) |
+-----------------------------------------------------------------------+

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

Date: 23 Apr 91 23:46:34 GMT
From: ogicse!uwm.edu!caen!kuhub.cc.ukans.edu![e-mail]
Subject: Sorry, this is a little off the subject

We, the CRS (Cheap Rocket Society of Kansas) are looking for stainless steel
air tanks rated (or formerly rated) for around 72 cubic feet or better, for
experimental use as fuel tanks.  We will pay for the tanks and shipping, but
remember, we are the *Cheap* Rocket Society.  Any help would be greatly
appreciated, so we can get our project off the ground.  Please respond via
E-mail.

Thanks.
--
 _____________________________________________________________________________
  And, Harry, who are you to judge me? -- Andy Nichols: 1991 -- also:
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~|   Barabas: ~A.D. 35 and
  [e-mail]       |   Hirohito:  1946
  [e-mail]            ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

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

Date: 24 Apr 91 01:34:05 GMT
From: agate!bionet!uwm.edu!caen!ox.com!hela![e-mail]  (Allen W. Sherzer)
Subject: Re: Saturn V and the ALS

In article <[e-mail]> [e-mail] (/dev/null) writes:

>What I was trying to say is that the only costs of the Saturn is not
>the booster.  The overall economic impact of stepping back 20+ years
>in technology because something might have had, at one time, a track
>record, might be devaststing in aerospace and other industries.

There is nothing in what I have said which precludes halting progress in
launch technology. You must understand that using the latest technology in
almost any operational system is a kiss of death. If we learn nothing from
the Shuttle, let's at least learn that. You want research? I agree, let's
do research. But at the same time, let's build our operational systems
with mature well understood technology. Saturn fits that bill much better
than ALS (although not as well as HL Delta or Titan V).

You want more recent technology in the Saturns? So do I. That is why we
need a program of continuous improvement to get it in. Want the very
latest materials used? Fine. Start an effort to build a composit nozzle
if you like. When it works, we add it to the existing design.

>(Also, much of the Saturn would have to be redesigned making it more
>of a Saturn VI than a Saturn V)

Just most of the tooling. The design of the launcher itself is already
there. That means we would need to do more testing than if we had the
tooling but still less than with ALS. Knowing the basic design works is
half the battle.

>We would lose the edge we have in Aerospace by making compromises of this sort.

IMHO by using our technology to build cheaper launchers we free up money
for research. This is how we will keep our edge in aerospace. Given a choice
between cheap products which work and expensive ones which don't work people
select the cheaper ones. This is why the Shuttle was such a disaster and why
ALS will be a disaster.

>The Saturn was an excellent rocket for its time.

The Saturn is also an outstanding rocket by our times. It lifts five times
what anything we have can lift and for a hell of a lot less per pound. Id
did it without fail or delay.

What other measure for excellence can there be?

>We CAN do better.

We have yet to do so. Nothing on the drawing boards will do so.

   Allen
--
+-----------------------------------------------------------------------------+
|Allen W. Sherzer | If you love something, let it go. If it doesn't come back |
|   [e-mail]   | to you, hunt it down and kill it.                         |
+-----------------------------------------------------------------------------+

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

Date: 23 Apr 91 19:05:55 GMT
From: pasteur!agate!bionet!uwm.edu!zaphod.mps.ohio-state.edu!think.com!spool.mu.edu!news.nd.edu!mentor.cc.purdue.edu!noose.ecn.purdue.edu!en.ecn.purdue.edu![e-mail]  (/dev/null)
Subject: Saturn V  vs. ALS


--
+-----------------------------------------------------------------------+
| Brent L. Irvine     |            These are MY opinions   |
| Malt Beverage Analyst     |            As if they counted...:) |
+-----------------------------------------------------------------------+

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

Date: 24 Apr 91 02:37:37 GMT
From: VAX1.CC.UAKRON.EDU!mcs.kent.edu!usenet.ins.cwru.edu!agate!tornado.Berkeley.EDU![e-mail]  (George William Herbert)
Subject: Re: Galileo status reports

In article <[e-mail]> [e-mail] (Michael V. Kent) writes:
>In article <[e-mail]> [e-mail] (Jay Glass) writes:
>>orbiter.  In a worst-case scenario, I have heard suggestions floated of
>>launching a communications relay in a direct trajectory to Jupiter in
>>order to "catch up"  with Galileo and make mission objectives reachable
>>using the low-gain antenna.
>That is an interesting idea.  If anyone knows any more about this, please say
>something.  Is there any way to alter the VEEGA trajectory in such a way as

I can't imagine getting it back to earth in any way... what we might be able
to do as an intermediate step between sending a comsat and doing nothing is
to launch a repair craft (or spare antenna 8-( on an rendezvous trajectory as
Galileo flys by in 1992.


Sending a com relay to Jupiter is probably overkill.  Sending one into a near-
Jovian transfer (with a few-year window of communications ability) would
be lower del-V and a lot cheaper.  [crank up them skunk works, ed...]


  == George William Herbert ==   *   JOAT = Jack Of All Trades = Generalist   *
 == JOAT for Hire: Anything, ==  #########  I do Naval Architecture, ##########
===+++ Anywhere, my price +++=== # Spacecraft Design, UNIX Systems Consulting #
 ==   [e-mail]   ==  # RPG writing/development, and lots of other #
  ==   [e-mail]   ==   ## random stuff, of course.  I'm a JOAT 8-) ##

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

Date: 23 Apr 91 19:44:37 GMT
From: agate!bionet!uwm.edu!spool.mu.edu!cs.umn.edu!uc!noc.MR.NET!gacvx2.gac.edu!vax1.mankato.msus.edu![e-mail]
Subject: <None>

Hello.  The name's Omne, any hardcore trek type person should recognize the
character, and I am looking for some information.
I'm doing a paper on geosynchronous satellites for a course here, and am
looking for relevant information on the topic.  Two main things I need to find
are 1) the number of objects in geosynchronous orbit, and 2) theories on how to
get a burned out satellite out of geo-orbit.
This isn't a joke; it's a term paper.
Hope to get some responses from you soon.

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

Date: 23 Apr 91 03:54:41 GMT
From: swrinde!cs.utexas.edu!news-server.csri.toronto.edu!torsqnt!geac!sq![e-mail]  (Mark Brader)
Subject: Re: R-100 and R-101


> In fact, the R-100 flew quite well and made a successful maiden voyage
> to Canada; there were some technical problems but nothing disastrous.
> The R-101 had grave trouble flying at all, needed hasty and ill-advised
> lengthening to have any hope of meeting its performance specs, and was
> generally over budget, behind schedule, and below expectations... and on

So badly behind schedule that the government fudged on its airworthiness
certificate.  The craft had *never* been tested at full speed before it
departed on its maiden voyage!

> its maiden voyage to India, this flagship of socialist progress crashed
> on a hillside in France with no survivors.

And a certain amount of justice in that the VIP fatality list included
many of those responsible for the disaster in the first place, both at
the political and technical levels.


> ... The R-100 was designed by Barnes Wallis, better known
> for the Wellington bomber, the Dambusters' bouncing bomb, and the Tallboy
> and Grand Slam giant penetrating bombs.

Another designer who worked on it was N. S. Norway, alias Nevil Shute.
His memoir of this part of his life is called Slide Rule, and is almost
certainly still in paperback print.  It's well worth reading.

(Some bookstores that carry it may put it with Shute's fiction.  I don't
know who publishes it in North America; I got my copy while overseas.)
--
Mark Brader              | "...not one accident in a hundred deserves the name.
SoftQuad Inc., Toronto   |  [This occurrence] was simply the legitimate result
utzoo!sq!msb, [e-mail] |  of carelessness."           -- Washington Roebling

This article is in the public domain.

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

End of SPACE Digest V13 #447
*******************