Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V11_1/V11_124.TXT

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Subject: SPACE Digest V11 #124

SPACE Digest                                     Volume 11 : Issue 124

Today's Topics:
               Re: More info on Pegasus
             Re: Challenger's Last Words
            Funding IS The Problem
               Re: Spacecraft on Venus
            Re: Launcher Development Costs
              Re: hubble telescope power
               Re: More info on Pegasus
               Phobos Pictures
       Re: Thiokol wasn't punished (was Re: Fun Space Fact #1)
      Re: Ejection seats (was Re: Challenger's Last...)
----------------------------------------------------------------------

Date: 7 Mar 90 05:04:36 GMT
From: agate!headcrash.Berkeley.EDU![e-mail]  (George William Herbert)
Subject: Re: More info on Pegasus

In article <[e-mail]> [e-mail] (S. Khai Mong) writes:
>In article <[e-mail]>
>    [e-mail] (George William Herbert) writes:
>#>   The second stage is controled by a cold-gas reaction control system
>#>which takes over immediately after the first stage seperates.  At 87 seconds
>#>into the flight, the third stage ignites, thrusting at an angle of 26
                        ^^^^^^
                         I _meant_ second stage here, appologies.


>#>above the horizon.
>#>. . .
>#>   an angle of 1.9 degrees to the horizon.  At this point the third
>#>stage ignites, and burns until 533 seconds, at which point the
>#>spacecraft is at 250 miles and 25,000fps velocity [orbital velocity].
>
>Is something wrong with the description of the stage firing timing
>descriptions?

Yes.  That first 'third' was really the second stage ignition.  My appologies.
Aside from that, peter yee mentioned that i spelled satellite wrong a few
times.  This ought to teach me to try and do an exhaustive technical posting
after two am :-)


*******************************************************************************
George William Herbert     JOAT For Hire: Anything, Anywhere: My Price
UCB Naval Architecture undergrad: Engineering with a Bouyant Attitude :-)
-------------------------------------------------------------------------------
[e-mail]       |||||||||| "What do I have to do to convince you?"-Q
[e-mail]      |||||||||||||||||||||||||||||||||||||||| "Die."-Worf
[e-mail] |"Very good, Worf. Eaten any good books recently?"-Q

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

Date: 7 Mar 90 17:41:50 GMT
From: usc!zaphod.mps.ohio-state.edu!uwm.edu!mailrus!jarvis.csri.toronto.edu!helios.physics.utoronto.ca!ists!yunexus!utzoo![e-mail]  (Henry Spencer)
Subject: Re: Challenger's Last Words

In article <[e-mail]> [e-mail] (Daniel Fischer) writes:
>... the front part of the orbiter emerged from the explosion
>in *one* part. And months later I heard that it most likely survived airtight!

"Most likely" is a vast overstatement.  There is some possibility that it
might have survived airtight.  Joe Kerwin's medical/forensic team tried
very hard to get a definite answer on that one, and couldn't -- impact
damage was too severe.  Reading between the lines in their report, it
looks to me like they guessed the answer was "no", but there wasn't any
solid evidence pointing either way.  My own feeling is that it's most
unlikely that the windows, in particular, all stayed intact.

>I've never heard anyone mentioning whether it would have been possible to add
>a parachute system that would have allowed a survivable landing?

Marginally possible, *if* you assume that the cabin separates cleanly from
the rest of the orbiter *without* separating from or damaging the parachute
system.  That's a very heavy load for a parachute, and the chute will be
heavy.  Deploying it reliably will probably require a mortar system, which
means the system will be an explosion hazard in a minor way.  Reliably
separating the cabin from the rest of the orbiter will require more
explosives, i.e. more weight and more hazards.  You'd need to test it at
least once and probably several times to make sure it works, which will
not be simple (that's a big, heavy mass for an aircraft to haul up to
altitude for testing).  This sort of thing isn't as easy as it sounds.

> Why does it
>seem to be so difficult to build such a system, that even the designers of the
>Hermes space shuttle finally decided to abandon the idea...

It's tricky engineering and there is very little real experience with it.
It also adds a lot of weight, complexity, and ongoing hazards.  (Even
ejection seats are heavy, complicated, and dangerous.)

>... Is it correct that such a
>system was once installed in a U.S. bomber but failed completely in the first
>*real* accident? Can somebody give me details about this incident?

The B-1A had an ejection-capsule system in its original design, but that's
probably not what you're thinking of.  They switched to ejection seats for
the B-1 because they couldn't make the capsule work well enough.  The F-111
has an ejection capsule, which is theoretically operational but has had
somewhat mixed results in practice.  I believe there have been successful
ejections with it, but it seems to be a rather unreliable system.
--
MSDOS, abbrev:  Maybe SomeDay |     Henry Spencer at U of Toronto Zoology
an Operating System.          | uunet!attcan!utzoo!henry [e-mail]

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

Date: 7 Mar 90 07:32:50 GMT
From: agate![e-mail]  (William Baxter)
Subject: Funding IS The Problem

This is another article forwarded for Jim Bowery.  Please direct all
responses to him.
----------------
From: [e-mail] (Jim Bowery)

Fred McCall writes:
>> agate![e-mail]  (William Baxter)
>>> There is strong pressure for bureaucracies like NASA or DoD and their
>>> contractors to push into development prematurely, rather than doing the
>>> necessary research.
>
>And why does that pressure exist, Mr. Baxter?  It's not simply
>because "development contracts are much more lucrative than research
>contracts".  That's certainly a good reason for a contractor to
>prefer development to research, but it hardly seem to cover the
>issue, since it's not the contractors who put out the RFPs.

I find it quite predictable that Fred McCall focuses on some hypothetical
Congressional preference for development over research and refuses to
acknowlege the fact that both the bureaucracies who issue the RFPs and
the contractors not only have an interest in maximizing their cashflows,
but also engage in intense lobbying (of questionable ethics and legality)
of Congress toward that end.

He is, after all, the person who coincidentally materialized to denounce
my posting of "Fun Space Fact #1: Launcher Development Costs" just as
all my subsequent messages to the space news/digest started "disappearing"
without an explanation or bounce-back even though all my other network
communications have been going through without any problem whatsoever.
(Yes, I've made "-request"s for an explanation to no avail.)

I'd like some net experts to send me email if they can come up with
plausible benign explanations for this state of affairs.  Present
circumstances create the appearance of a possible federal crime.

There is a lot in common between this government subsidized "net" and
the government funded space operations of NASA:  By providing
subsidy for this communications network, bureaucrats and their apologists
can inhibit private alternatives from being capitalized and patronized, thus
keeping this potentially powerful means of communication as a forum for
pork-barrel politics (as advocated by Fred McCall of TEXAS (JSC/SSC)
Instruments and the National Space Society) while filtering out opposing
views.

As one of the coauthors of the original Plato network "notes" program
who has worked with CDC, AT&T, Knight-Ridder and others on the establishment
of entirely private communications services in competition with "the net",
I can speak with from direct experience in saying that as long as the government
persists its subsidies (most of the "private" companies providing support are
getting most of their revenue from the government), there will be no genuine,
open and viable competition in network communications services for free
expression of opinion on public policy and those who are paid to implement
it with our tax dollars.
---
Typical RESEARCH grant:
$
Typical DEVELOPMENT contract:
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$

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

Date: 6 Mar 90 21:26:54 GMT
From: bnrgate!bnr-fos!bmers58!![e-mail]  (Henry Troup)
Subject: Re: Spacecraft on Venus

In article <[e-mail]> [e-mail] (Mike Van Pelt) writes:
>Better, you could build a probe designed to operate at Venus surface
>temperature.  (At 800 degrees?  Right.  It would probably be easier to
>build the heat pump.)  Semiconductors are out....

TIMMs (Thermally Integrated Micro Modules) are it - a set of ceramic
and metal vaccuum tubes, sealed and the whole assembly is heated to
a nice warm red glow.  Heat dissipation - why measure ?  Good 1950's
technology.

The big transmitting tube might be a problem, but solvable, I think.

Drop a vaccuum tube probe, and receive signals with something more
'modern'? TV would be hard, though.
--
Henry Troup - BNR owns but does not share my opinions
..utgpu!bnr-vpa!bnr-fos!hwt%bmerh490 or  [e-mail]

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

Date: 6 Mar 90 20:49:42 GMT
From: agate![e-mail]  (William Baxter)
Subject: Re: Launcher Development Costs

I am forwarding this article for Jim Bowery, who has suddenly lost
access to the net.  Please direct all replies to him.
---------------------

Fred McCall writes:
>Yes, NASA needs lots of changes.  I can think of bunches myself.
>But, a large part of what needs changed is being mandated by
>micro-management of programs by the next highest layer of
>bureaucracy, and that problem extends all the way to Congress.  So I
>say to fix it where it *starts*, at the top.

I agree with Fred McCall on this issue except I'm sure he won't
like the WAY I agree with him. :-)

Under no circumstances should we find our Congressmen debating with
NASA managers about the details of budget, schedule and the
perversities of technical developments.  The sooner that kind of garbage
ends, the sooner we can look forward to real progress in space.

Congress is not competent to manage or oversee technically complex
projects and therefore should not attempt to do so.  It should,
instead, prioritize RESULTS and associate funds with those RESULTS.
All funding should be COD, to WHOEVER DELIVERS FIRST.  What do NASA's
space centers do?  Who cares?  Maybe sell them off to the highest bidder
and/or let them go belly up, hopefully as soon as possible.

By "RESULTS" I mean those things which are of intrinsic value (from
a taxpayer standpoint) and objectively verifiable by appropriate
Congressional subcommittees or their delegates.  This can be anything
from a high resolution gamma-ray map of the moon to a giant inflatable
Dan Quayle painted day-glow yellow and placed in polar orbit.

If no one delivers RESULTS on an item, Congress can either increase
the associated COD payment or retire the cash reserve.  No money wasted.

This is a more general version of a proposal I've been circulating around
Congressional staffers on a "National Science Trust" which would pay out
for delivery of quantifiable information, such as digital maps at various
frequencies, etc. of various bodies and atmospheres.
---
Typical RESEARCH grant:
$
Typical DEVELOPMENT contract:
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$

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

Date: 7 Mar 90 03:42:34 GMT
From: [e-mail]  (Nick Kline)
Subject: Re: hubble telescope power

Oops.  I can't believe that the article got cut off at the top.

Should say,

Here at the university of arizona, there has been a raging controversy
over a plan to build several telescopes on a nearby mountain, Mt. Graham.

(And the .article file saved for me has the correct article, grumble grumble)

-nick kline
---
    "Computer Scientists are at the top of the nerd heap" - Curtis Dyreson

Nick Kline, Univ. of Az., Computer Science, Tucson, AZ 85721
([e-mail] -or- {noao|allegra|cmcl2}!arizona!kline)

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

Date: 7 Mar 90 00:54:21 GMT
From: skipper![e-mail]  (Mary Shafer (OFV))
Subject: Re: More info on Pegasus

In article <[e-mail]> [e-mail] (George William Herbert) writes:


>Pegasus was origionally scheduled to fly before christmas.  This was delayed
>after problems mating the rocket to the B-52 were discovered in flight tests.
>First launch is expected in the next month.  It should be noted that there
>have been no delays due to the rocket itself, and that the entire development
>program has been done in only twenty months including the delay, from concept
>to first flight.

Not quite correct.  The mating problems were discovered _before_
any flight tests were conducted.  That is, until the Pegasus was
correctly mounted, the B-52 wasn't even moved.  I should point out
that the mating problems were caused by the Pegasus, since it didn't
fit as it should have.

Also, numerous electrical problems in the Pegasus have caused quite
a bit of delay in the program.  Some of these were discovered _in_
flight, much to everybody's dismay.

The source of my information is post flight briefings and status
reports from OSC and involved NASA team memebers.

--

Mary Shafer  [e-mail] or ames!skipper.dfrf.nasa.gov!shafer
         NASA Ames Dryden Flight Research Facility, Edwards, CA
                   Of course I don't speak for NASA

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

Date:     Wed, 07 Mar 1990 12:00 EST
From: DAVID SIMMONS <[e-mail]>
Subject:  Phobos Pictures
To: <[e-mail]>

     Have any of the pictures the Soviets got back from their Phobos probe
before it failed been published , and where could I find them?

     David Simmons

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

Date: 7 Mar 90 16:09:30 GMT
From: [e-mail]  (SERRE GLENN)
Subject: Re: Thiokol wasn't punished (was Re: Fun Space Fact #1)

In article <[e-mail]> [e-mail] (Cliff White) writes:
>Who builds SRB's for Titan? As i recall, Thiokol was only one of several
>experienced sources bidding when the program started.
>
The current SRMs for Titan III and IV are built by United Technology's
Chemical Systems Division.  New SRMs (Solid Rocket Motor Upgrade, SRMU) are
being developed for the Titan IV
by Hercules, which also builds smaller solid rockets for the
Delta (and probably some others).

--Glenn Serre
[e-mail]

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

Date: 7 Mar 90 22:10:29 GMT
From: uokmax!munnari.oz.au!goanna![e-mail]  (Tony Basaranowicz)
Subject: Re: Ejection seats (was Re: Challenger's Last...)

[e-mail] (David Smith) writes:

>>I belive that the incedent in question refered to the second XB-70 ...
>>The crew of the XB-70 had an ejection capsule (a cross between a
>>seat and a pod) which was designed to protect the crew in the event of a
>>ejection at high mach numbers. It was belived that the high g's
>>encountered durring the dive prevented the capsule from deploying.

>The XB-70 had one pod per pilot.  One got out, the other didn't.  The one
>who did almost didn't, since the clamshell clamped down on his elbow near
>the pivot.  He had to work hard to dislodge his elbow, whereupon the
>clamshell closed and successfully ejected.  I suspect that the second pilot
>never got his elbow out.

Also, an inflatable shock-absorbing bag located beneath the ejection capsule
did not inflate. The capsule impacted and the pilot was subject to a decele-
ration of about 45g's. He sustained internal injuries but thankfully lived.

I think this was the incident where an F-104 plowed into one of the vertical
tails of the XB-70.

----------------------------------------------------------------------------
Tony Basaranowicz      Computer Science,
                       Royal Melbourne Institute of Technology,
                       Australia.
E-mail:                [e-mail]
----------------------------------------------------------------------------

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

End of SPACE Digest V11 #124
*******************