Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V12_5/V12_575.TXT

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Date: Mon, 19 Nov 1990 01:35:19 -0500 (EST)
Subject: SPACE Digest V12 #575

SPACE Digest                                     Volume 12 : Issue 575

Today's Topics:
        Re: Reliability and Insurance (3 of 3)
        Source for satellite tracking programs
        NASA Prediction Bulletin Distribution
        Re: Reliability and Insurance (3 of 3)
           Re: Misc: Space Station and ACRV
            POTENTIAL MAJOR FLARE WARNING

Administrivia:

    Submissions to the SPACE Digest/sci.space should be mailed to
  [e-mail].  Other mail, esp. [un]subscription notices,
  should be sent to [e-mail], or, if urgent, to
             [e-mail]

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

Date: 14 Nov 90 23:20:18 GMT
From: agate!dog.ee.lbl.gov!hellgate.utah.edu!caen!umich!sharkey!cfctech!teemc!fmeed1![e-mail]  (Russ Cage)
Subject: Re: Reliability and Insurance (3 of 3)

In article <[e-mail]> [e-mail] (Wales Larrison) writes:
>... the OPF bottleneck is reduced by merely eliminating the redundant
>system checks to ensure the first checkout was correct.)

Considering how complex Shuttle is, this sounds like a really
*bad* idea from where I stand.  The reliability achieved by
the Shuttle software group is due to their checkout procedures.
--
Russ Cage    Ford Powertrain Engineering Development Department
Work:  itivax.iti.org!cfctech!fmeed1!cage   (CHATTY MAIL NOT ANSWERED HERE)
Home:  [e-mail]  (All non-business mail)
Member:  HASA, "S" division.

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

Date: Sat, 17 Nov 90 01:21:06 MST
From: Dan Charrois <@BITNET.CC.CMU.EDU:[e-mail]>
Subject: Source for satellite tracking programs

  Is anyone aware of a location where I can get ahold of the source code
to a satellite tracking program (C preferable).  I don't have an IBM
or compatible, so I can't just use an executable file.  If the source
is at a site from which it can be ftp'd, so much the better.
  Thanks for your assistance....Dan

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

Date: 17 Nov 90 20:11:19 GMT
From: ncis.tis.llnl.gov!blackbird![e-mail]  (TS Kelso)
Subject: NASA Prediction Bulletin Distribution


After some feedback from sci.space readers worldwide, it would appear that
somewhere in the distribution process the NASA Prediction Bulletins are
being eliminated due to their size.  I have taken the step of breaking the
file into two parts for distribution this weekend.  If you get this message
but do not get the elements (which were posted just prior to this message),
please let me know and we'll see if we need to further reduce the size of
the file to get the data through.  - TS
--
Dr TS Kelso                           Assistant Professor of Space Operations
[e-mail]          Air Force Institute of Technology

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

Date: 17 Nov 90 21:46:59 GMT
From: van-bc!ubc-cs!news-server.csri.toronto.edu!utgpu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: Reliability and Insurance (3 of 3)

In article <[e-mail]> [e-mail] (Russ Cage) writes:
>>... the OPF bottleneck is reduced by merely eliminating the redundant
>>system checks to ensure the first checkout was correct.)
>
>Considering how complex Shuttle is, this sounds like a really
>*bad* idea from where I stand.  The reliability achieved by
>the Shuttle software group is due to their checkout procedures.

The question is, how much *extra* reliability is bought by all those extra
checks?  Wales is suggesting that it approaches zero; I am inclined to agree.
--
"I don't *want* to be normal!"         | Henry Spencer at U of Toronto Zoology
"Not to worry."                        |  [e-mail]   utzoo!henry

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

Date: Sun, 18 Nov 90 17:32:26 -0500
From: "Allen W. Sherzer" <[e-mail]>
Subject: Re: Misc: Space Station and ACRV
Newsgroups: sci.space
Cc:

In article <[e-mail]> Wales Larrison writes:
>>4. Conceptual Design Study for Modular Inflatable Space Structures,...
>>   I don't have an address for ILC.

>  Try ILC Dover, P.O. Box 266 Warrington Rd, Frederica, DE 19946.
>Phone [phone].  That's the group at ILC which manufactures
>spacesuit parts and life support systems.

That should be them. Thanks for posting the address.

>   Also, I'm surprised why no one has discussed a prime factor
>regarding the possible use of a Soyuz for the Space Station ACRV
>role -- the Soyuz is rated only for a duration of 120-160 days in
>space.

I thought it was 180 days?

>After launch of a Salyut or Mir crew,, the Soviets rotate
>the on-orbit Soyuz spacecraft with each "visiting" Cosmonaut crew,
>having the visitors come up with a "fresh" capsule, and return with
>the "old".

I would assume LLNL would do the same.

>    We would either have to redesign Soyuz, reuse them, or rotate
>them.  Redesigning them, we might as well design in compatibility
>with other U.S. systems (like ELVs), and compatible subsystems.
>But, I don't think we'd save money - to get 10+ years in space we'd
>need to rework and change every subsystem.

Agreed. Besides, Soyuz would never be more than a stop-gap effort.
This effort should go into a better design with longer life and
bigger capacity.

>  If we rotate Soyuzes to keep a fresh set on orbit (we would need
>at least 3 for a 8 man space station crew -more if we assume 1 may
>be unavailable when needed), the cost is $150 M every 120 days in
>procurement (using your $50M per Soyuz value and assuming no
>learning curve since the Soviets are already far down the curve).

There may or may not be a learning curve. The Soviets do crank them
out like hotcakes but who knows if they build them efficiently. If
we produced them under licence, there may or may not be reductions
as we figure out how to do it better.

>If we can stretch the space-qualified period to 180 days (added
>costs...), we can get by with $300 Million per year.  Since it'll
>probably take an Atlas II to launch each at about $60 M per launch
>(not including orbital rendezvous capability, which also needs to be
>added in...), so there's another 6*60= $360M per year.  Sums to
>about $660 Million per year for a Soyuz-based ACRV.

These costs seem reasonable to me. Now for the interesting part:
If we use Soyuz at the main method of transportation, is this
cheaper than using the Shuttle? It seems to me that the answer
is yes since we are getting a year's worth of rotation for less
than the cost of one Shuttle flight. Alternatively, if we used
the Shuttle for transport, would Soyuz be better as an ACRV than
the ACRV NASA proposes? From what I have seen, I think the answer
is also yes but I don't have enough information for an educated
assessment.

>   Or, we could spend some DDT&E money and develop a system to last
>10-30 years on orbit, and be maintainable on orbit.  Compared to
>$6.6 B per decade derived above, a $2-3 B development cost (if we
>believe that number...) is preferred.

I agree that this is the best solution assuming the system is
procured properly.

  Allen

--
+---------------------------------------------------------------------------+
|Allen W. Sherzer| I had a guaranteed military sale with ED-209. Renovation |
|   [e-mail]  | programs, spare parts for 25 years. Who cares if it      |
|                | works or not?  - Dick Jones, VP OCP Security Concepts    |

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

Date:    Sun, 18 Nov 90 01:28:53 MST
From: [e-mail] (Cary Oler)
Subject: POTENTIAL MAJOR FLARE WARNING
X-St-Vmsmail-To: ST%"[e-mail]"

            /\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\

                     POTENTIAL MAJOR FLARE WARNING

                         ATTENTION  ATTENTION

            /\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\


                        12:00 UT, November 18


ATTENTION:

     A massive sunspot group has developed and is currently located at
approximately N19E19 as of 12:00 UT, 18 November.  This sunspot group has
the potential to produce a major class M or X flare.  It consists of 78 spots
clustered within a Beta-Gamma-Delta magnetic configuration, covering an area
of 9,000 million square kilometers (5,600 million square miles)!  This Region
(6368) is currently a type FKI optical region and has produced three class M
flares over the past 24 hours.

     THIS REGION HAS THE POTENTIAL TO PRODUCE MAJOR ACTIVITY.

     The Space Environment Services Center estimates a 25% to 35% probability
of a major class X flare occurring from this region over the next 72 hours.
There is an estimated 80% probability of moderate-level M-class flare activity
occurring from this region over the next three days (minimum).  There is a 15%
to 25% probability of a major proton flare erupting from this region over the
next 72 hours.  The Space Environment Services Center has issued a condition
YELLOW alert status for potential PCA and satellite-level proton events for the
next 24 to 72 hours at least.  The risk for strong PCA and proton event
activity will increase as this region moves towards the western solar
hemisphere.

     Region 6368 has grown in size and complexity over the past 24 hours.  Two
delta-configurations have developed in the trailer spot complex of this system
over the past 24 hours.  This region has the potential to produce some potent
activity.

     There is a strong potential that a moderate to high intensity SID (Sudden
Ionospheric Disturbance) accompanied with a moderate to high intensity SWF
(Short Wave Fade) may occur as a result of major flare activity over the next
2 to 5 days on the sunlit hemisphere of the earth.  SID and SWF durations
could exceed 80 to 120 minutes.  Polar regions are at risk for strong PCA
activity over the next 2 to 5 days, depending on further developement of
Region 6368.  Users of polar ionospheric properties (ie. radio operators,
researchers, etc.) should be on the alert for potential PCA activity.
Satellite users should be on the alert for potential proton events and
associated potential satellite disruptions.

     Region 6368 might not produce any major flare activity.  However, the
evidence would seem to indicate otherwise, considering the size, magnetic
complexity, and spot density of this major system.  Should a major flare
occur, a major flare alert will be issued with details concerning the event.


            /\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\

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

End of SPACE Digest V12 #575
*******************