Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V16_0/V16NO050.TXT

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Date: Fri, 15 Jan 93 05:06:48
From: Space Digest maintainer <[e-mail]>
Reply-To: [e-mail]
Subject: Space Digest V16 #050
To: Space Digest Readers
Precedence: bulk


Space Digest                Fri, 15 Jan 93       Volume 16 : Issue 050

Today's Topics:
                            averting doom
            Broadcasting shuttle audio over the Internet?
                      Cooling re-entry vehicles.
                        Defuse Xray Experiment
                        Elementary Ballistics
                       Freedom's orbit (2 msgs)
          Galileo Stuck Ribs / Remote Manipulator?  (5 msgs)
                   High temperature superconductors
                   IP for pub/SPACE/GIF wanted!!!!!
Lubrication problem (was Re: Galileo Stuck Ribs / Remote Manipulator?)
                        Oxygen in Biosphere 2
              Subjective Safety Measure(Re: man-rating)
             Two-Line Orbital Element Set:  Space Shuttle
             What's it like at the edge of the universe?
                        What was NASA thinkin

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

Date: Thu, 14 Jan 93 22:14:35 GMT
From: "John C. Baez" <[e-mail]>
Subject: averting doom
Newsgroups: sci.astro,sci.space,sci.physics,sci.environment

In article <[e-mail]> [e-mail] (Patricia C. Vener-Saavedra) writes:
>Hi there. As I recall, in about a billion years the sun will have
>about twice the luminosity it presently has. The average surface of
>Earth will be about 100 degrees C. Some lakes and rivers will have
>begun to boil. It will not be pleasant for homo sapiens.:-)

Luckily homo sapiens will be not around by then.  Even in terms of
biological evolution, a billion years is a long time.  With
cultural-technological evolution, it's a *really* long time.

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

Date: 15 Jan 93 03:53:02 GMT
From: Mark Bixby <[e-mail]>
Subject: Broadcasting shuttle audio over the Internet?
Newsgroups: sci.space.shuttle,sci.space,comp.protocols.misc,comp.protocols.tcp-ip

An article posted recently to sci.space.news mentions that some folks at
NASA will be broadcasting NASA SELECT shuttle mission audio over MBONE and
the Internet.  Where can I go to learn more about this audio broadcasting
protocol?  I.E. what RFC numbers, hardware requirements, FTP software
repositories, etc...
--
Mark Bixby                         Internet: [e-mail]
Coast Community College District   1370 Adams Avenue
District Information Services      Costa Mesa, CA, USA  92626
Technical Support                  [phone]
"You can tune a file system, but you can't tune a fish." - tunefs(1M)

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

Date: 14 Jan 93 13:19:47 GMT
From: Paul Johnson <[e-mail]-mrc>
Subject: Cooling re-entry vehicles.
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Gary Coffman) writes:

>Even the SR71 uses fuel to help cool it's titanium skin, and it travels
>more than four times slower than a re-entry vehicle.

Why not use a total-loss cooling system in a re-entry vehicle?  I
gather that ablative cooling works on this principle: as the shield
reaches its maximum temperature it ablates, leaving fresh, cooler
shield underneath.  So would a titanium skin with cooling pipes
underneath it work?  The coolant would be used once and then dumped
behind the vehicle.

Alternatively I gather that JPL has looked into aerobraking manouvers
that involve flying engine-first into the atmosphere and running the
motors at "idle".  Because the engine exhaust is already moving with
the vehicle, it streams back around the vehicle and keeps the
atmosphere at a safe distance.  So you could use an SR71-style fuel
cooling system, dump the hot fuel into an engine in the nose and then
use the resulting exhaust to protect the vehicle still more.  Am I
making sense.

BTW, I have read the FAQ on ideas to improve space travel.  I know
there is probably a good reason why this can't work/isn't done.

Paul.

--
Paul Johnson ([e-mail]).        | Tel: [phone] ext 3245
--------------------------------------------+----------------------------------
These ideas and others like them can be had | GEC-Marconi Research is not
for $0.02 each from any reputable idealist. | responsible for my opinions

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

Date: 14 Jan 93 23:03:25 GMT
From: Steinn Sigurdsson <[e-mail]>
Subject: Defuse Xray Experiment
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Tom Schruefer) writes:

   >With the successful deploy of TDRS-F, STS-54's other primary payload bean
   >operations. During orbital night, the Diffuse X-Ray Spectrometer will tke
   >measurements of the x-ray background of the solar system's interstellar
   >medium. This information will be used to answer questions about a nearb
   >super nova that scientists believe occurred about 300,000 years ago.

      Does anyone know which star they are talking about ???

Hmm, sound like they're trying to see the local bubble
in the ISM (conventional wisdom is that Sol is in a overhot
and underdense patch of the ISM, probably due to a supernova
within 300 ly about 300,000 years ago - the gamma-ray source
Geminga is a candidate descendant of that supernova, it's close
and young). So, they are probably not looking at a single object
but the diffuse emission all around us.

|  Steinn Sigurdsson    |I saw two shooting stars last night        |
|  Lick Observatory    |I wished on them but they were only satellites    |
| [e-mail] |Is it wrong to wish on space hardware?        |
| "standard disclaimer"    |I wish, I wish, I wish you'd care - B.B. 1983    |

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

Date: Fri, 15 Jan 93 01:23:00 EST
From: John Roberts <[e-mail]>
Subject: Elementary Ballistics

-From: [e-mail] (Steve Boylan)
-Subject: Elementary Ballistics
-Date: 14 Jan 93 15:59:40 GMT
-Organization: Digital Equipment Corporation

-What speed (using the term to refer to the magnitude of the
-velocity vector) must be imparted to a body at the surface of
-the Earth to achieve low Earth orbit?  I've seen estimates
-bandied about that ranged from 2.2 km/sec. to 8 km/sec.
-Naturally, I can't recall enough of basic mechanics to
-figure it out for myself, and I can't find my mechanics
-text . . .

Just thinking about the problem, there can't be a single simple answer,
because the drag-to-mass ratio will be different for different payloads.

If you look at the broader question that includes delta-V to orbit for
conventional rockets, it's even more complicated, because you're both
resisting the Earth's gravity and building up orbital velocity and
altitude at the same time. The slower your rocket goes up, the greater
the total delta-V needed from your propulsion system to achieve orbit.
(An extreme case would be the fictional nuclear-powered rocket in "The Mouse
on the Moon", that took off at several miles per hour. :-)

If there's a formula that includes these factors, I'd sure like to hear it.

Dani Eder gives a number for DC-1:

#From: [e-mail] (Dani Eder)
#Subject: Re: Saving an overweight SSTO....
#Date: 12 Jan 93 20:59:35 GMT
#Organization: Boeing AI Center, Huntsville, AL

#Working DC-1:

#Delta V to orbit including drag and g-losses: 9144 m/s

If you use a linear launcher, then required delta-V would probably be less
(not sure, because you waste more energy going through the lower atmosphere),
but you have much greater heating, maximum dynamic pressure, and stress
due to launch acceleration, so your vehicle must be much sturdier than a
conventional rocket.

I think somebody mentioned recently that if you want to use a linear launcher
to get to circular LEO with minimal additional rocket thrust, you should
throw the payload to extremely high altitude, use a small rocket thrust to
get it into a highly eccentric orbit that grazes the atmosphere at perigee,
allow aerobraking to lower the apogee to somewhere around the final altitude
you want, then apply rocket thrust a second time near apogee to raise the
perigee out of the atmosphere and circularize the orbit. That requires
high total delta-V, but hopefully delta-V from the linear launcher costs
less per m/s than delta-V from the rocket thruster, and a higher percentage
of your final orbital velocity comes from the linear launcher if you do it
this way than if you do your initial boost to low altitude.

John Roberts
[e-mail]

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

Date: 14 Jan 93 22:49:00 GMT
From: Greg Macrae <[e-mail]>
Subject: Freedom's orbit
Newsgroups: sci.space

In article <[e-mail]>, [e-mail] (Shadan M. Ardalan) writes...
>In article <MCh=[e-mail]> [e-mail] (Sean C Fifield) writes:
>>  I'm interested in orbital information (altitude, eccentricity,
>>inclination, etc.) about the space station Freedom.  Has NASA
>
>This isn't the gospel....but last I heard, Freedom is to be in roughly
>a 200 nmi circular orbit inclined 28.5 degrees (a standard inclination for
>launching due east from the Cape)....will someone please confirm or correct
>my numbers?......thanks
>
The orbit is planned to vary depending on the solar cylce.  The minimum
altitude will fall between 180 and about 210 n.m.  The maximum altitude
will vary with the configuration (mass and drag), but will be planned to
provide a low altitude for shuttle rendezvous.  The inclination will be
28.5 deg. (probably the one orbital parameter that has never changed) and
the orbit should be approximately circular.

Greg (Space Propulsion Technology Div. LeRC)

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

Date: 15 Jan 93 01:56:00 GMT
From: [e-mail]
Subject: Freedom's orbit
Newsgroups: sci.space

In article <[e-mail]>, [e-mail] (Shadan M. Ardalan) writes...
>In article <MCh=[e-mail]> [e-mail] (Sean C Fifield) writes:

>This isn't the gospel....but last I heard, Freedom is to be in roughly
>a 200 nmi circular orbit inclined 28.5 degrees (a standard inclination for
>launching due east from the Cape)....will someone please confirm or correct
>my numbers?......thanks
>
>Shadan M. Ardalan
>

Try 230 nautical miles at 28.5 degrees. Call the Public affairs officer at
Boeing Huntsville for all the station info you ever wanted. [phone]
for Boeing information to get to the PAO.  They also might have it on
NASA spacelink now too. I forget the internet address though.

Testing for station elements is well underway here. We will be having some
great tours during the SEDS national conference here in August. Come one
come all.

Dennis, University of Alabama in Huntsville

*Less than 60 days to the first launch of the Small Expendable Deployer*
*System (SEDS). Twenty km tether and fify lbs end mass. Stay tuned for
*more details.

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

Date: Thu, 14 Jan 1993 19:04:50 GMT
From: Henry Spencer <[e-mail]>
Subject: Galileo Stuck Ribs / Remote Manipulator?
Newsgroups: sci.space,sci.astro,alt.sci.planetary

In article <[e-mail]> [e-mail] (John P. Mechalas) writes:
>... the VEEGA trajectory eventually had
>to be designed.  This forced the Galileo to fly near the sun, which in turn
>forced the engineers to develop a folding antenna to protect it from the
>sun's heat.  Hence the joints, and hence the stuck ribs.

Uh, sorry John, but Galileo had a folding antenna almost from the start.
The antenna is too big to fit in the payload volume of any US launcher,

be it shuttle or expendable.  The only effect the VEEGA trajectory had
was to require that the antenna be kept folded until after the first
Earth encounter.  (Otherwise it would have been unfurled in Earth orbit
and the problem could have been dealt with by the shuttle crew.)

The VEEGA redesign of Galileo was strictly a shoestring operation, which
made minimal changes to an already-built spacecraft on a minimal budget.
(Unfortunately, one consequence of this was that the antenna-motor
reversing relay got diverted to other uses... after all, nobody thought
they'd have to reverse the antenna motor.)
--
"God willing... we shall return."       | Henry Spencer @ U of Toronto Zoology
       -Gene Cernan, the Moon, Dec 1972 |  [e-mail]  utzoo!henry

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

Date: Thu, 14 Jan 93 21:03:49 GMT
From: "John P. Mechalas" <[e-mail]>
Subject: Galileo Stuck Ribs / Remote Manipulator?
Newsgroups: sci.space,sci.astro,alt.sci.planetary

In article <[e-mail]> [e-mail] (Henry Spencer) writes:
>Uh, sorry John, but Galileo had a folding antenna almost from the start.
>The antenna is too big to fit in the payload volume of any US launcher,
>be it shuttle or expendable.  The only effect the VEEGA trajectory had
>was to require that the antenna be kept folded until after the first
>Earth encounter.  (Otherwise it would have been unfurled in Earth orbit
>and the problem could have been dealt with by the shuttle crew.)
>
>The VEEGA redesign of Galileo was strictly a shoestring operation, which
>made minimal changes to an already-built spacecraft on a minimal budget.
>(Unfortunately, one consequence of this was that the antenna-motor
>reversing relay got diverted to other uses... after all, nobody thought
>they'd have to reverse the antenna motor.)

From _Exploring Space_, William E Burrows, page 341:

   "There was a good possibility that the science boom sunshade would
block the Sun sensor used for navigation, so a second Sun sensor had to
be considered.  And since Galileo was now to fly close to Earth, it's
large high-gain antenna had to be made to close to prevent damage from
solar heating:  open, it would act like a large solar collector and there-
fore become damaged.  It would be opened again, like a beach umbrella, once
Galileo was safely past Earth.  The mission planners didn't like that
because opening and closing the antenna-- working the mechanism--
invited single point failure.  If the antenna stuck in the closed position
the mission was over."

   You are right...the antenna was made to open originally.  A deeper
check into my sources revealed that Mr Burrows was a bit vague on that
point in his book.   The fears that the engineers had came from the
opening and closing mechanism, not the ribs themselves.  As it turns
out, the engineers were right...but there wasn't enough money or time
to redesign the spacecraft.
   It's amazing how many design changes Galileo had to undergo
throughout it's lifetime.

--
John Mechalas                                          "I'm not an actor, but
[e-mail]                                 I play one on TV."
Aero Engineering, Purdue University                     #include disclaimer.h
--
John Mechalas                                          "I'm not an actor, but
[e-mail]                                 I play one on TV."
Aero Engineering, Purdue University                     #include disclaimer.h

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

Date: Thu, 14 Jan 1993 20:36:35 GMT
From: "forrest.e.gehrke" <[e-mail]>
Subject: Galileo Stuck Ribs / Remote Manipulator?
Newsgroups: sci.space,sci.astro,alt.sci.planetary

In article <[e-mail]> [e-mail] (Gary Coffman) writes:
> It's just
>unfortunate that zero defects inspections prior to launch didn't catch
>the loss of lubricant in this case. A squirt of Dri-slide at the Cape
>would have avoided this problem entirely.
>
>Gary

Who told you that loss of lubricant was the problem?  How about a
broken or cracked rib, or some other less obvious reason for the
jam?

Forrest Gehrke [e-mail]

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

Date: 15 Jan 93 00:28:42 GMT
From: Craig Keithley <[e-mail]>
Subject: Galileo Stuck Ribs / Remote Manipulator?
Newsgroups: sci.space

In article <[e-mail]>, [e-mail] (Henry
Spencer) wrote:
>
> (Unfortunately, one consequence of this was that the antenna-motor
> reversing relay got diverted to other uses... after all, nobody thought
> they'd have to reverse the antenna motor.)

What did they use the reversing relay for?

Craig Keithley
Apple Computer, Inc.
[e-mail]
"I have absolutely no responsibility in this matter, what-so-ever"

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

Date: 15 Jan 93 00:33:05 GMT
From: Craig Keithley <[e-mail]>
Subject: Galileo Stuck Ribs / Remote Manipulator?
Newsgroups: sci.space

In article <[e-mail]>, [e-mail] (Gary
Coffman) wrote:
>
It's just
> unfortunate that zero defects inspections prior to launch didn't catch
> the loss of lubricant in this case. A squirt of Dri-slide at the Cape
> would have avoided this problem entirely.
>

More processes!  We need more processes!!!...  Total Quality Management
should be applied.  And we need a process to catch those things that need
processes.  And I can't reply to any flames unless you file a Flame
response form 3Q-173-A.

Craig Keithley
Apple Computer, Inc.
[e-mail]
"I have absolutely no responsibility in this matter, what-so-ever"

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

Date: Fri, 15 Jan 93 00:52:38 EST
From: John Roberts <[e-mail]>
Subject: High temperature superconductors

-From: [e-mail] (Jason Cooper)
-Subject: ** BUSSARD RAMSCOOP **
-Date: 13 Jan 93 14:27:50 GMT
-Organization: TradeNET International Trade Corp.

-Second thing that I've been thinking about...  What's the average
-temperature of space (just "empty" space, not including planets, etc)?
-I've been reading up about superconductors and found one that apparently
-can THEORETICALLY reach superconductivity even at 160 degrees kelvin (or
-was that the real measurement?).  Just wondering if the temperature of
-deep space would help much in the way of cooling the magnetic coils and
-other components of HUGE concern.  Also, does anybody know if a
-superconducting electromagnet still works?  Would that work for the
-collection magnets?

There's an article on high-temperature superconductors and magnetic fields
in the February 1993 issue of Scientific American. I haven't had time to
read it in detail.

>From a brief scan, I gather that the existing materials haven't been as
resistant to magnetic fields as had been hoped (a superconductor stops
superconducting when it's penetrated by a magnetic field), but there may
be ways to fix the problem.

John Roberts
[e-mail]

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

Date: Thu, 14 Jan 93 21:35:52 GMT
From: Irmgard Heeb <[e-mail]>
Subject: IP for pub/SPACE/GIF wanted!!!!!
Newsgroups: sci.space

this is an urgent search for the IP-Address where all the gif's archived!
I've allready been at that host but I've lost the address now so I hope
there's someone able to give me the right information

thank's a lot for any assistance...
rgds chris

---
  Irmgard Heeb ([e-mail])
  C.A.T. Kommunikations-System, Frankfurt, Germany

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

Date: 14 Jan 93 23:54:52 GMT
From: Bill Higgins-- Beam Jockey <[e-mail]>
Subject: Lubrication problem (was Re: Galileo Stuck Ribs / Remote Manipulator?)
Newsgroups: sci.space,sci.astro,alt.sci.planetary

In article <[e-mail]>, [e-mail] (forrest.e.gehrke) writes:
> In article <[e-mail]> [e-mail] (Gary Coffman) writes:
>> It's just
>>unfortunate that zero defects inspections prior to launch didn't catch
>>the loss of lubricant in this case. A squirt of Dri-slide at the Cape
>>would have avoided this problem entirely.
>>
>>Gary
>
> Who told you that loss of lubricant was the problem?  How about a
> broken or cracked rib, or some other less obvious reason for the
> jam?

Loss of lubricant during truck travel is the best guess of Galileo's
engineers.  It's been reported in *AvLeak* and in JPL's *Galileo
Messenger*.

This is especially vivid if you've seen the episode of PBS's *Nova*
(possibly *Horizon* to the Brits-- N runs lots of H's episodes)
dealing with Galileo's pre-launch troubles.  The journey by truck from
California to Florida is covered in some detail.

--
     O~~*           /_) ' / /   /_/ '  ,   ,  ' ,_  _           \|/
   - ~ -~~~~~~~~~~~/_) / / /   / / / (_) (_) / / / _\~~~~~~~~~~~zap!
 /       \                          (_) (_)                    / | \
 |       |     Bill Higgins   Fermi National Accelerator Laboratory
 \       /     Bitnet:     [e-mail]
   -   -       Internet:  [e-mail]
     ~         SPAN/Hepnet:      43011::HIGGINS

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

Date: Thu, 14 Jan 93 22:36:00 PST
From: [e-mail]
Subject: Oxygen in Biosphere 2



Biosphere 2 update, 01/14/93

Oxygen began coming in yesterday, thus far the O2 has
been increased by 0.5% to 14.9%. The total addition will be slow,
over about the next 10 days. Yes, the oxygen is actually
being removed from the Biosphere 2 atmosphere. In fact
we are missing 12,000 kg of oxygen. Although biological
de-nitrification is producing a small amount of nitrogen
gas, it only accounts for a very small fraction of the
observed decrease in the relative concentration of oxygen.
The number of moles of air in Biosphere 2, as calculated
from the volume in the variable chambers and
temperature etc., is decreasing. The observed decrease in
atmospheric mass corresponds to the rate of oxygen loss.
Also the relative concentration of other noble gasses like
argon, and trace gasses added like SF6, confirm a removal
of the oxygen has occurred. The capacity of the variable
volume chambers has been enough to handle the reduced
total volume.

The symptoms are the same as at high altitude, though
remember that we have "ascended the mountain" over a
period of 15 months. The slow reduction in the partial
pressure of oxygen has allowed us to acclimate so the
effect is slightly different from that of suddenly
experiencing reduced pO2, as in a flight simulation
chamber. Our respiration and hart rate increased  and
changes in the chemistry and composition of our blood
occurred in order to help compensate for the reduced
pO2. The acute medical problems with reduced pO2 are
associated mainly with the rapid accent of a mountain or a
rapid reduction in pO2.

We all went to the location where the oxygen was being
injected and the result was quite invigorating. After
suddenly breathing air with a full compliment of oxygen,
for the first time in over a year, I must say that the
difference is quite profound. The oxygen not only effected
me physically in the form of easier of breathing, generally
increased energy and increased work capacity , but also
emotionally. I am less irritable and I feel like I am
emerging from a pot of thick goo. Also thinking seems to
go faster and more accurately. Others of the crew have
reported similar effects.  If anybody out there is taking
your air for granted, I'd reconsider. This experience brings
home to me the extreme seriousness of depending on a
life support system for the years involved in a Mars
mission. Whether the system is physical chemical,
biological or some combination of both, insidious problems
that slowly effect the crews performance will tend to
create a positive feedback system, the less the crew is
capable of handling the situation, the worse the situation
gets. There is not going to be a quick rescue mission
possible if things go wrong at any significant distance from
Earth.

Taber MacCallum
Biosphere 2 crew
[e-mail]



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

Date: Fri, 15 Jan 1993 01:03:06 GMT
From: "K.R. Flanagan" <[e-mail]>
Subject: Subjective Safety Measure(Re: man-rating)
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Bruce Watson) writes:
>|Ah, this guy has never heard of elevator accidents?
>|While kinda uncommon they do occur.  mostly due to improper door opening.
>
>Contrary to all the movies we've seen, there has never been an elevator
>fatality since Otis designed the safety features of the modern elevator
>in the late 19th century.
>
>--
>Bruce Watson (wats@scicom) Bulletin 629-49 Item 6700 Extract 75,131

    Sorry to waste bandwidth, but there was a fatality a few years
   ago up here in Rochester N.Y., I remember it making the six o'clock
   news. Now how about some on topic threads?!
                -Kevin
                [e-mail]

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

Date: Thu, 14 Jan 1993 21:19:49 GMT
From: TS Kelso <[e-mail]>
Subject: Two-Line Orbital Element Set:  Space Shuttle
Newsgroups: sci.space

The most current orbital elements from the NORAD two-line element sets are
carried on the Celestial BBS, [phone], and are updated daily (when
possible).  Documentation and tracking software are also available on this
system.  As a service to the satellite user community, the most current
elements for the current shuttle mission are provided below.  The Celestial
BBS may be accessed 24 hours/day at 300, 1200, 2400, 4800, or 9600 bps using
8 data bits, 1 stop bit, no parity.

Element sets (also updated daily), shuttle elements, and some documentation
and software are also available via anonymous ftp from archive.afit.af.mil
(129.92.1.66) in the directory pub/space.

STS 54
1 22313U 93  3  A 93 14.15936342  .00049404  00000-0  20070-3 0    46
2 22313  28.4702 150.5461 0021832 189.1570 300.6608 15.84313209    93
--
Dr TS Kelso                           Assistant Professor of Space Operations
[e-mail]                    Air Force Institute of Technology

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

Date: Fri, 15 Jan 1993 03:12:32 GMT
From: "robert.f.casey" <[e-mail]>
Subject: What's it like at the edge of the universe?
Newsgroups: sci.space

I remember reading in (I think) Sky & Telescope some years ago an
article about the universe, and some theories on it's origin (big
bang, and such).  One theory said something to the effect that our
universe was expanding, and was surrounded by a larger area of some
sort of superdense material.  As if the universe was a bubble of
mostly empty space expanding inside this superdense material.
Which leads to the question: Is there a boundry, where you can
stand right next to the "surface" of the universe bubble, and
touch with your spacesuited hand the wall of superdense material?
Would it be dark, or bright, perfectly smooth, or with irregularities
like mountians (microns high, miles high, lightyears high?)?
Could you walk on it, is there gravity (lots of gravity like millions of
G's, or none, what happens if a meteorite hits the surface (bounce off,
stick, big energy explosion, disappear?)?

I suspect that I'm only half remembering an analogy in a discription
of some theory of multiple universes.

But the above questions sound like something some sci fi story writer
could build an interesting environment for a good story.

But is there even any connection with reality to this?

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

Date: 13 Jan 93 23:33:00 GMT
From: George Gassaway <[e-mail]>
Subject: What was NASA thinkin
Newsgroups: sci.space

In article <[e-mail]>
[e-mail] (Ralph Buttigieg) writes:
> c> A shuttle with 5 or 6 J-2s using 2 uprated F-1s in the recoverable
> c> boosters would have taken advantage of a history of literally
> c> dozens of successful flight firings.  Plus there would
> c> have been a much wider range of abort modes.
>
> But how reusable were the Saturn engines? Then again, how reusable are
> the SSME...

The real problem is in reusing the F-1's after they got dunked in the
Atlantic ocean. I recall reading something long ago investigating the
prospects of adding chutes to the Saturn-V first stage (and adding air
bags?), to allow reusing them. However a major problem was decontaminating
the critical metallic  parts that had been exposed to salt water.

Let's see now, take 8-10 SSME's in a cluster, add them to one BIG tank,
throw in some wings, and you can avoid that nasty dunk in the Atlantic by
gliding to a runway landing to reuse the "carrier vehicle. But, OMB wanted
it to cost less to develop even if it cost a hell of a lot more to fly,
ergo we got the throwaway ET & reusable but troublesome SRB's.

---
 This copy of Freddie 1.2 is being evaluated.


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

End of Space Digest Volume 16 : Issue 050
------------------------------