Space & Astronomy/Space and Astronomy (October 1993).iso/pc/text/spacedig/v13_0/v13_095.txt

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Subject: SPACE Digest V13 #095

SPACE Digest                                      Volume 13 : Issue 95

Today's Topics:
          Re: Commercial Space News (2 of 4)
    Re: Why man rate? (was: space news from Dec 17 AW&ST)
              Re: SPACE Digest V13 #041
             Re: Books to start out with.
    Re: Why man rate? (was: space news from Dec 17 AW&ST)
              Re: More on space cameras

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: 26 Jan 91 04:32:52 GMT
From: julius.cs.uiuc.edu!zaphod.mps.ohio-state.edu!swrinde!elroy.jpl.nasa.gov!zardoz.cpd.com!dhw68k!ofa123![e-mail]  (Wales Larrison)
Subject: Re: Commercial Space News (2 of 4)

(Black Brandt - Canada), LTV (Scout), and all of the small ELV
competitors in the US, as well as Deutche Aerospace (Texus -
Germany/ESA), IAA (Shavit - Israel), ISAS (M3 derivative- Japan) and
several others.  For recoverable satellites their competition
includes the COMET recoverable satellite program from the CCDS, the
Carina program from Italy, the Chinese recoverable satellite
program, and the Soviet recoverable payload program.]

CHINA'S GREAT WALL CORPORATION'S LONG MARCH MANIFEST
   According to recent information, China plans 7 Long March
launches through 1992.  These are:

   Fall   1991       Arabsat-1C;
   Winter 1991       Aussat-B1;
   Winter 1991       Feng Yun weather satellite;
   Spring 1992       Freja Swedish satellite;
   Spring 1992       CSAT recoverable satellite;
   Summer 1992       CSAT recoverable satellite;
   Summer 1992       Aussat-B-2;
   Fall   1992       Dong Fang Hong-2 comsat.


LOCKHEED ENTERS FRAY FOR LOW-COST SATELLITES
    Lockheed Missiles & Space Company is entering a new low-cost
satellite bus in the competition to build medium-weight satellites.
Called "F-Sat" for "frugal satellite," the all-aluminum bus is being
designed from the ground up for cost saving and ease of manufacture.
Lockheed calculates by building a common source for payload power,
propulsion, data management, attitude control and other services,
they can cut the price from an average of $60 million to as low as
$30 million for a satellites with a payload of 2,000- 4,000 lbs.
The F-Sat is being sized to accommodate payloads ranging from 750-
4,500 pounds, with an on-orbit lifetime of as long as seven years,
and a power of 2.400 kilowatts.  Developed with Lockheed money, and
supported by a company investment of more than $20 million on
computerized design and manufacturing tools, and a "software
engineering environment" and other software development tools, the
first F-Sat bus should be tested by mid-1993.
   [Commentary.  This is a new entry into the LEO satellite
construction market.  It has been rumored that LMSC has built some
number of DoD satellites for this market, but a new low-cost
satellite bus is a departure from the specialized DoD satellite
market.  Their primary competition will be from Ball, GE, TRW, and
Fairchild, and Rockwell. The only other advertised multi-purpose low
cost bus is from Fairchild's Multi-Mission Modular Satellite used
for NASA scientific payloads, but GE has used a very similar
satellite bus for several LEO payloads.  Evidently the LEO satellite
market is starting to hot up again, with the number of satellites
expected to grow from the Iridium constellation from Motorola,
lightsats from the DoD, and increased number of small scientific
satellites, including a potentially large number from a re-focused
Mission to Planet Earth.  We'll see more details on this as some of
the competitor's positioning becomes apparent, bids are made for
these systems, and some of the details of the bids are released.]

MOTOROLA HAS SELECTED A SUB-CONTRACTOR FOR IRIDIUM SATELLITES
   It was reported Motorola has announced it has selected a sub-
contractor to build the satellites for their proposed Iridium low-
Earth orbiting cellular communications system.  77 satellites, plus



--
Wales Larrison
Internet: [e-mail]
Compuserve: >internet:[e-mail]
--------------------------------------------------------------------------

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Date: 25 Jan 91 16:54:43 GMT
From: rochester!uhura.cc.rochester.edu!ub!ubvmsd.cc.buffalo.edu![e-mail]  (Craig L Cole)
Subject: Re: Why man rate? (was: space news from Dec 17 AW&ST)

In article <[e-mail]>, [e-mail] ("Allen W. Sherzer") writes...
>In article <[e-mail]>:
>
>>>>I also don't think it would cost that much to man-rate one of the more
>>>>reliable, smaller launchers such as the Delta,

[Stuff delelted]

>>It would cost substantially more.  First of all, you'd have to develop
>>a capsule, with attendent redundant flight controls, life support,
>>heat shields, adaptors and fairings, etc.
>
>We use Soyuz. We mount it on a Delta for 20% the cost of a Shuttle
>flight. We could also put it (and 50K to 100K pounds extra payload)
>on a Delta or Titan derived HLV for half the cost of a Shuttle flight.

I think you're underestimating the difficulty in mating these two
completely different animals. Ever try making an IBM and a Mac
work together?

[Stuff about ELV and shuttle success rates deleted]

>Now if you where going into orbit would you rather fly on the launcher
>with a 98.3% record or a 96.6% record? If the less safe one costs five
>times as much, how would that affect your decision?

BOTH success rates are impressive. I don't think anyone can accurately
say that the shuttle is exactly 1.7% more dangerous than ELVs. There's
too much guesswork.

If we don't learn to operate shuttles, we'll be lauching atop ELVs
forever. The NASP program wouldn't exist either. The shuttle isn't
what it was expected to be, but it still is a major step in the
right direction.

>>Although it's hard to quantify due to the small sample
>>size, the Shuttle over several hundred flights should do substantially
>>better than that (if that many flights were made), and I daresay that if it
>>didn't, it would be canned pronto.
>
>Don't look now but the Shuttle *IS* being canned.

That's just not true. No replacements after Endeavour are likely to
be built, but the shuttle will be running probably well into the
21st century. Just when Hermes, Hope and whatever else are just
getting launched.

What is true, is that the shuttle, being the expensive vehicle it is,
is being used for what it is best at -- life sciences, micrograv
research, delicate deploys, etc. No more run-of-the-mill satellite
deploys. They SHOULDN'T be launched via the shuttle. Its not only
cheaper to do it with ELVs, but it takes away from true sciences
and experiments only the shuttle can perform.

[Stuff about man-rating adding safetly deleted]

Sure, adding safety and redudancy features increases the complexity
of the system, which in actually starts to reduce safety. But, after
seeing all of the glitches the shuttle has usually easily solved
by these features, I'd rather take my chances having those extra
systems to use.

I know what you're going to say -- a lot of those glitches wouldn't
have happened if everything weren't so complex. But this is my own
opinion. I wonder what astronauts think.

>BTW, on January third Norm Augustine made the exact same point in a
>Congressional hearing. As you know his committee advocates building
>a heavy lift vehicle. One member asked him about man-rating this new
>launcher. He pointed out that may not be needed because of the
>safety of the hardware. It turns out that the system MUST be safe
>enough for people because the payloads are worth far far more
>than the crew. If it wasn't safe, nobody would fly their payloads
>on it.

This is EXACTLY the way rockets SHOULD be built.

Man-rating a rocket will eventually become an outdated term, as rockets
will become inherently be safe enough to launch whatever you want --
satellites, manned capsules, or whatever.

Craig Cole
[e-mail]
[e-mail]

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

Date: 26 Jan 91 19:20:56 GMT
From: usc!elroy.jpl.nasa.gov!freedom![e-mail]  (David Cornutt)
Subject: Re: SPACE Digest V13 #041

[e-mail] (Tommy Mac) writes:

>Re: Al Globus' Mirrors vs. Turbines vs. Photocells for Biospheres:
>
>Blow the Trubines and the Photocells.  Mirrors get 100% efficiency (in the
>frequencies that the plants care about anyway).

Um, no.  Telescope builders know that aluminized mirrors are only about
80% efficient at visible and ultraviolet wavelengths.  You can do a
little bit better with silver, but it's expensive and it corrodes, and
it still doesn't get near 100%.

It's still a good idea in spite of this.

--
David Cornutt, New Technology Inc., Huntsville, AL  [phone]
([e-mail]; some insane route applies)
"The opinions expressed herein are not necessarily those of my employer,
not necessarily mine, and probably not necessary."

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

Date: 27 Jan 91 04:19:37 GMT
From: zaphod.mps.ohio-state.edu!swrinde!cs.utexas.edu!news-server.csri.toronto.edu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: Books to start out with.

In article <[e-mail]> [e-mail] ("Allen W. Sherzer") writes:
>A friend of mine with a degree in ME has asked me to reap from
>the collective wisdom of the net. He would like any good intro
>books on rocket design and engine design.

Slightly more information would be useful.  Just how "intro" are we talking
about?

Hunter's "Thrust Into Space" is a good intro for someone who really doesn't
know anything about propulsion, although it spends a lot of time on things
like orbital dynamics which aren't entirely relevant to this query.  Alas,
it's long out of print.

Sutton's "Elements of Rocket Propulsion" currently seems to be the definitive
text for aspiring undergraduate propulsion engineers.  The fifth edition is
a current MIT text, for example.  I'd guess this is about right.

Huzel and Huang's "Design of Liquid-Propellant Rocket Engines", NASA SP-125,
although somewhat old is *the* hot-and-heavy book on engine design.  Nothing
much beyond this is available collected in one place.  (Remember that there
are very few active practitioners of this particular craft, so there is
little demand for advanced books; the active people pass it on to their
successors less formally.)  Trouble is, it's out of print.  Still available
from NTIS, however, and the reproduction is actually fairly good.

This is from memory; small spelling/wording errors are possible.
--
If the Space Shuttle was the answer,   | Henry Spencer at U of Toronto Zoology
what was the question?                 |  [e-mail]   utzoo!henry

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

Date: 25 Jan 91 20:06:39 GMT
From: swrinde!elroy.jpl.nasa.gov!freedom![e-mail]  (David Cornutt)
Subject: Re: Why man rate? (was: space news from Dec 17 AW&ST)

I apologize to the group for posting this, but people that play fast and
loose with their facts burn me up.  Hit 'n' if you are adverse to flames.

[e-mail] ("Allen W. Sherzer") writes:

>We use Soyuz. We mount it on a Delta for 20% the cost of a Shuttle
>flight. We could also put it (and 50K to 100K pounds extra payload)
>on a Delta or Titan derived HLV for half the cost of a Shuttle flight.

Are you saying that you could design a Titan with 130-150K lb payload
capacity?  Contrary to popular belief, the Titan IV is only about a
50K payload vehicle.  And it's a ragged-edge design.  There's no way
that it could ever be man-rated.  You can't go on adding thrust to a
vehicle forever.  If you tried to uprate Titan IV to this payload
capacity, you'd wind up, in effect, designing a new vehicle.

>That's the problem. We double the cost of everything to get 0.01%
>more safety out of it. It's just not worth it.

Actually, I agree with you.  But Congress and the American public
don't agree.  In their minds, 0.01% risk is not acceptable for
a manned vehicle.

>>I just got out some Martin Marietta literature on the Delta.  In it they
>>advertise a launch success rate of 93.9%.

>You need to look deeper since Martin makes the Titan not the Delta. They
>will fudge the figures to make Titan look better.

>In the entire 30 year history of the Delta this is an accurate figure.
>However, their success rate over the last 13 years is 98.33%. Independant
>estimates of Shuttle success rates put it at about 95% and it's operational
>record so far is about 96.66%.

You can make the probability be anything you want if you pick and choose your
data points.  If you only consider the last 11 flights, the Shuttle has a
100% success rate.  This of course proves nothing.  Since the basic
vehicle design has not changed, I stand by the 93.9% figure.

>Don't look now but the Shuttle *IS* being canned.

If you are saying that there will be no more Shuttle flights, that's
news to me.  Do you know something that the rest of us don't?

Of course, there won't be any more built.  You may find this strange,
but I agree with that.  I was opposed to building Endeavor -- as another
copy of the _current_ Shuttle design.  By now, we should be working on
the next version of that vehicle, the one that will put us nearer to
single-stage-to-orbit (with horizontal takeoff), better reliability, and
lower operations cost.  If you're saying that the Shuttle concept in
general is a bad idea, I totally disagree.  In this day and age of
recycling, why is everyone so anxious to build throwaway launchers?

>There is no need to ask them. We HAVE sent people up on Delta's

When?

>Not from what I can see. The Shuttle is at best no safer than the non-man
>rated alternatives and at worse a little less safe.

Comparisons of reliability between the Shuttle and unmanned ELV's are
difficult to make, because of their radically different natures.
The number of Shuttle flights already flown is not a sufficient sample
to derive a rating from that.

>BTW, on January third Norm Augustine made the exact same point in a
>Congressional hearing. As you know his committee advocates building
>a heavy lift vehicle. One member asked him about man-rating this new
>launcher. He pointed out that may not be needed because of the
>safety of the hardware. It turns out that the system MUST be safe
>enough for people because the payloads are worth far far more
>than the crew. If it wasn't safe, nobody would fly their payloads
>on it.

But the Delta, which is the thing that you keep harping on, isn't.
(Again, Delta folks, please don't feel like I'm picking on you; the
Delta just happens to be the ELV that I know the most about, other
than the late great Saturns.  And no, I'm not going to bring up
the recent incident on a flight where a payload failed due to
miswiring of the adaptor; that had nothing to do with the design
of the vehicle and so isn't relevent to this argument.)  The main
problem with the Delta, as far as man-rating, is that steering
of the first stage is provided solely by gimbaling of the main
engine.  If that engine fails, the vehicle has no directional
control and must be aborted.  This happened on a Delta launch in
1987; I've been told that it has happened in the past, too.

My point is, there is a reason why things are man-rated, and it
isn't to keep contractors employed.  The reason is that Congress
and the American public *insist* on the absolute lowest
perceived risk (which does not necessarily correlate to the
actual risk).

--
David Cornutt, New Technology Inc., Huntsville, AL  [phone]
([e-mail]; some insane route applies)
"The opinions expressed herein are not necessarily those of my employer,
not necessarily mine, and probably not necessary."

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

Date: 25 Jan 91 20:25:43 GMT
From: sdd.hp.com!elroy.jpl.nasa.gov!freedom![e-mail]  (David Cornutt)
Subject: Re: More on space cameras

Thanks for a fine article, Charles.  A couple of questions?

(1) Does exposure to vacuum effect film?  (Apart from the thermal problem)
(2) What kind of film were the photographs you mentioned shot with?  Was
this a stock professional film, or was it specially formulated for the
purpose?
(3) If it was stock film, how was it preserved on board?

--
David Cornutt, New Technology Inc., Huntsville, AL  [phone]
([e-mail]; some insane route applies)
"The opinions expressed herein are not necessarily those of my employer,
not necessarily mine, and probably not necessary."

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

End of SPACE Digest V13 #095
*******************