Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V16_2/V16NO241.TXT

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Date: Mon,  1 Mar 93 05:23:46
From: Space Digest maintainer <[e-mail]>
Reply-To: [e-mail]
Subject: Space Digest V16 #241
To: Space Digest Readers
Precedence: bulk


Space Digest                Mon,  1 Mar 93       Volume 16 : Issue 241

Today's Topics:
                        Apollo Moon Missions ?
                         Battery help needed!
                 JPL's 'faster, better, cheaper' goal
 LOCAL DISTURBANCE - a new method of quantutative flow visualization
                       Nobody cares about Fred?
                       payload return from Fred
                       Proposed Mercury Mission
                          Refueling Centaurs
    Reliable Source says Freedom Dead, Freedom II to be developed
       SSF Resupply (Was Re: Nobody cares about Fred?) (2 msgs)
                         The NASA Budget Myth
                   Ulysses Mysteriously Shuts Down

    Welcome to the Space Digest!!  Please send your messages to
    "[e-mail]", and (un)subscription requests of the form
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    (BITNET), rice::boyle (SPAN/NSInet), utadnx::utspan::rice::boyle
    (THENET), or [e-mail] (Internet).
----------------------------------------------------------------------

Date: Fri, 26 Feb 1993 16:29:00 GMT
From: "E. V. Bell, II - NSSDC/HSTX/GSFC/NASA - (301" <[e-mail]>
Subject: Apollo Moon Missions ?
Newsgroups: sci.space

In article <[e-mail]>, [e-mail] writes...
>   I am ignorant, I admit it. My memory has failed. Can someone refresh my
>tired brain cells, and tell me (us) which Apollo mission to the Moon was the
>last one? There couldn't have been too many.
>
>   Mille Mercis
>
>---
>------------------------------------------------------------
>Timothy J. Thompson, Earth and Space Sciences Division, JPL.
>Assistant Administrator, Division Science Computing Network.
>Secretary, Los Angeles Astronomical Society.
>Member, BOD, Mount Wilson Observatory Association.
>
>INTERnet/BITnet:    [e-mail]
>NSI/DECnet:         jplsc8::tim
>SCREAMnet:          YO!! TIM!!
>GPSnet:             118:10:22.85 W by 34:11:58.27 N
>

    Apollo 17. Also the only flight to include one of the
    scientist-astronauts.

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

Date: 26 Feb 93 16:06:10 GMT
From: "T. Andy Frakes" <[e-mail]>
Subject: Battery help needed!
Newsgroups: sci.space,sci.electronics,sci.aeronautics,sci.chem,sci.engr

In article <[e-mail]> [e-mail] (kevin.w.mckiou) writes:
>In article <[e-mail]> [e-mail] (Benjamin John McCall) writes:
>>Does anyone have any information on alternative battery technologies, or
>>even suggestions about who I might get in touch with (by phone or by email)?
>>
>
>You might look into Ni-Cads.  100 lbs of Sanyo high-capacity cells
>KR-2800CE could deliver ~163 amp-hours at 12 volts.  That's just
>19% short of your goal.  I would try contacting Sanyo directly to
>get some idea of what else might be available.
>
>Good Luck!

I'd second this motion.  Sanyo, Gates, and a few other companies make
high quality Ni-Cads of varying sizes.  Write or call them and they'll
send you nice pretty tables of their batteries (sizes, weights, storage,
etc.)  I used them in a design for a senior project on a battery-powered
hang-glider/sailplane during my undergrad.  Weight was the determining
factor for our project.

-Andy
================================================================
=             T. Andy Frakes ([e-mail])              =
=                                                              =
= This user does not believe in smiley faces.  Insert your own =

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

Date: 26 Feb 1993 17:27 UT
From: Ron Baalke <[e-mail]>
Subject: JPL's 'faster, better, cheaper' goal
Newsgroups: sci.space,sci.astro,alt.sci.planetary

From the "JPL Universe"
February 26, 1993

The future is now for JPL's `faster, better, cheaper' goal

     The Caltech Management Association recently brought together
leading JPL experts for a panel discussion entitled, "Faster,
Better, Cheaper:  How JPL Is Doing It?," which sought to inspire,
encourage and motivate a standing room only crowd about the
changes ahead for the Laboratory.
     The moderator was Deputy Director  Larry Dumas, who began
the forum by giving the von Karman Auditorium audience a dose of
reality. "NASA's budget over the next several years will not
permit any new starts except for small or moderate-sized
missions," he said, "and JPL and its contractors need to be
believably faster, better, cheaper."
     The panel, whose job it was to address this issue, included
E. Kane Casani, former manager of the Miniature Seeker Technology
Integration (MSTI) project; Tony Spear, manager of the Mars
Environmental Survey (MESUR); Donna Pivirotto, team leader for
the Microrover; and Robert Staehle, preproject manager of the
Pluto Fast Flyby.
     Casani has the distinction of having tackled the first JPL
mission that falls into the faster, better, cheaper category --
MSTI -- which was recently completed on time and under budget.
     "We did MSTI for $15 million and we did it on schedule,"
Casani told the audience.
     Part of the secret of MSTI's success was involving everyone
who worked on the project and achieving a consensus early on
about how the mission was going to be completed. "We set the
schedule for one year and we all knew what we were talking
about," Casani said.
     Backing up that schedule was also important. "Every
subsystem was fully funded," he said. "Every division had the
money to do the job. We didn't have any cost overruns."
     Casani had some advice for his colleagues. "The challenge is
to do things with rapid development," he said. "We've got to
learn not to reinvent the wheel. It's important to contain the
scope of the job to the customers' requirements."
     Tony Spear heads up the next "small" mission to be
undertaken at the Lab. He told the crowd that MESUR/Pathfinder
will be the first of NASA's Discovery series of faster, better,
cheaper missions and it is due for launch in 1996.
     Spear said one of his biggest challenges is figuring out how
to do things differently. Such changes will require JPL to
reinvent itself, he said, and rethink the way the Lab currently
does business.
     "It takes hard work, and everyone at JPL must participate,"
Spear continued. "We have a lot of theory that now needs to be
brought into practice.
     "It will take daring and continuous effort" to make a
low-cost MESUR a reality, Spear said.
     "We're a fixed-price project.  We need to maintain
sufficient reserves, but we also need to accomplish a productive
mission and at the same time, we have to be attractive enough to
justify the mission. It's important to communicate the risks
involved with low-cost missions and to mitigate risk we will
assemble quickly and then test, test, test before we launch," he
concluded.
     One person who hopes Spear's team succeeds is Donna
Pivirotto, whose microrover is set to fly onboard MESUR/ Path-
finder as a technology experiment. The microrover's goal is to
evaluate the performance of small rovers on Mars' terrain.
     To get that job done, Pivirotto explained, "the Lab has had
to undergo a paradigm shift away from big rovers to small,
short-range rovers.
     "We've taken out some performance and added risk," she said,
"but we hope to get a big bang for a small buck."
     The microrover will use a majority of commercial parts, and
it will pick up where the development of Rocky IV left off.
Pivirotto prefers to call the rover a micro-spacecraft, because
it has all the functions of a typical planetary spacecraft, plus
it must interact with an uncertain and relatively hostile
environment.
     But it is not only the rover that is changing. The project's
management is daring, too. "We have no managers on this project,
so there is nobody in the way," she quipped as she explained that
she technically is the project's "team leader," not its
"manager."
     "What we are doing is flying the first autonomous rover, and
it's really a culture shock to the operations people," Pivirotto
continued.
     Rob Staehle knows what that feels like as he tries to put
together the first mission to Pluto. It will not be easy. With a
cost cap of $400 million, Staehle has tried to keep the
objectives very clear.
     "JPL has the people, the facilities and the experience to do
planetary exploration that is second to none. But we must
eliminate unnecessary work along the way," he said.
     Staehle and his team must figure out a way to control
mission operations costs, get to Pluto within eight years and get
the data back quicker. Such goals require taking greater risks.
"There is no 100 percent reliable mission," Staehle continued.

     He said he already has learned some lessons about how not to
get bogged down in the process. "One thing I have found valuable
has been to frequently and informally keep my managers and
sponsors aware of what's happening."
     The launch of the two spacecraft appears feasible for 1999,
with arrival at Pluto in 2007.
     After the two-hour discussion, many in the crowd seemed
buoyed by what they had heard and some expressed hope that these
projects would indeed become a reality. Key ingredients to
success, Dumas observed, appeared to be teaming with suppliers
and customers and having fun while taking on really tough
challenges.
                                  ###
     ___    _____     ___
    /_ /|  /____/ \  /_ /|     Ron Baalke         | [e-mail]
    | | | |  __ \ /| | | |     Jet Propulsion Lab |
 ___| | | | |__) |/  | | |__   M/S 525-3684 Telos | If you don't stand for
/___| | | |  ___/    | |/__ /| Pasadena, CA 91109 | something, you'll fall
|_____|/  |_|/       |_____|/                     | for anything.

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

Date: Fri, 26 Feb 1993 08:01:41 GMT
From: "Dmitry V. Stepanov" <[e-mail]>
Subject: LOCAL DISTURBANCE - a new method of quantutative flow visualization
Newsgroups: sci.space

LOCAL  DISTURBANCE  -  a   new   method   of   quantitative   flow
visualization!
        Method is very effective for high temperature flows up to 5000K
( tested in the range 1000K-3500K), but can also be  used  at  a  lower
tempe-ratures. Workable in  dusted  and  chemically  active  flows  not
transparent  for  light.   In   some   modifications   applicable   for
visualization on the burning surfaces,  solid  propellant  surface  for
example. Range of velocities testedfrom 5-10 m/s up to  1000  -1500m/s.
In  most  cases  direction  and  module  of  velocity  vector  are  got
simultaneously on a grid of test points,  covering  the  surface  under
examination.  Special  equipment  needed  for   realization   no   more
complicated then for oil specters method.
        Examples of realizations can be presented.
        Searching for method application for solving different problems.
        Dr. Sergey K. Savelyev

For letter use
E-Mail : [e-mail]

or :
        EMBC,Box 222,St.-Petersburg,197022,Russia
        phone. [phone] or (812) 2344930
   or Home: Altayskaya str., 12,34,St.-Petersburg,196066,Russia
      Home phone. [phone]

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

Date: Fri, 26 Feb 1993 17:12:52 GMT
From: fred j mccall 575-3539 <[e-mail]>
Subject: Nobody cares about Fred?
Newsgroups: sci.space

In <[e-mail]> [e-mail] (Brian Stuart Thorn) writes:

>>You seem to be assuming fueling as a dedicated mission to arrive at
>>the 'no difference in cost' conclusion.  Either that, or you are
>>assuming that an entire removable thruster module is not going to
>>weigh any more or take up any more space than a large tank of fuel to
>>fill it.  I don't think either of those are good assumptions, hence
>>replacing thruster modules rather than refueling them costs more
>>(because you have t lift more weight and volume to accomplish the
>>refueling in the replacement case, and hence can't carry something
>>else that will have to be brought up or accomplished on another
>>mission).

>    I've read this paragraph a few times and still can't figure out
>    what you're trying to say. >:-(

Well, let me see if I can spell it out, then.  A tank of fuel and a
refueling rig are going to weigh and cube much less than the same
amount of fuel installed in a module that includes tankage, engine,
attachment points, etc.  What that means is that you can lift more
stuff at a time on a given launcher if you use refueling as opposed to
using replaceable thruster modules.  In order to say that the two
methods 'cost the same', you have to assume one of the following
things to get around the preceding reasoning:

1) Fueling will always be a dedicated mission, so excess lifting
capacity of the vehicle is irrelevent; we're going to launch a mission
regardless, and that costs us the same no matter what we lift.

2) Fuel pre-installed in replaceable thruster modules will bulk and
mass no more than the same amount of fuel in a refueling tank, plus
the hardware to do the refueling.

I don't see why you should necessarily assume either one of those
things.

>    What I was trying to say, however, is that a refueling mission and
>    a module replacement mission are both likely to be dedicated flights.

Why?  There seems no reason for this to be the case.  Wouldn't it be
more economical to bring up food, replacement parts, new equipment,
etc., all on the same flight?  If the preceding reasoning makes sense,
then it is a net win to use refueling technology as opposed to
replacing entire thruster modules.

>    Therefore, I don't see how a module replacement is more expensive
>    than a refueling mission. At least not if both missions are Shuttle
>    based.

Given that assumption, it isn't.  However, as I said, I think that is
a poor (or at least a wasteful) assumption.

>    Allen said something, I think, about replacement method needing
>    a bunch of extra modules (one on Fred, one on ground in overhaul).
>    This is true, but offset by the need to develop orbital refueling
>    technology for the alternative, and refueling will still need some
>    type of fuel carrier, pumps, etc. Shuttle is coming home anyway, so
>    I don't see how carrying back empty modules is particularly expensive.

I don't consider the cost of bending some extra metal to be
particularly burdensome.  However, the inspection you would probably
want to put the 'used' thrusters through likely would be.  The
military learned a long time ago that in a lot of cases it makes more
sense to *not* do 'maintenance' on something that is working properly.
Opening it up for maintenance necessitates a certain risk of breaking
it, and hence for critical components pretty much says you rebuild,
whether it needs it or not.  Better to provide a certain amount of
redundancy and service them when their performance starts to deviate
from optimium.

>>And if the Shuttle is grounded and the station is forced into
>>free-drift for lack of replacement thruster modules (which is the same
>>thing as saying that it ran out of fuel), then where are you?  It all
>>comes down to just how much money and opportunity cost is a small
>>incremental change in safety worth.  It is this failure at rational
>>risk analysis that has earned parts of NASA the poor reputation for
>>performance and cost effectiveness that they have.

>    Its clear there are arguments both for and against the module
>    swap-out method. In my previous post, even I said I would like
>    to see a backup refueling capability. However to keep costs down
>    (ahem, har har) NASA could chose only one method. As I said, and
>    you ignored, I cannot fault NASA for choosing the safer of the
>    two methods, which swap-out unquestionably is.

Why is this safer?  Seems to me that an on-orbit accident involving a
12k thruster/fuel package crashing into Freedom would be much more
serious than the worst 'fuel leak' I can imagine.  The *technological*
risk is probably smaller, but avoidance of all technological risk is
hardly the sort of behaviour I want to see from an organization whose
charter is, at least in part, to push technology development.

--
"Insisting on perfect safety is for people who don't have the balls to live
 in the real world."   -- Mary Shafer, NASA Ames Dryden
------------------------------------------------------------------------------
[e-mail] - I don't speak for others and they don't speak for me.

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

Date: 26 Feb 93 17:59:08 GMT
From: Anthony J Stieber <[e-mail]>
Subject: payload return from Fred
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Henry Spencer) writes:

>Why not?  Most of it will be more useful up there than down here.  And
>a heavier station is *better*, because it reduces the frequency with
>which reboost is needed; even trash is more useful as station ballast
>than as return cargo.

Trash could be even more useful as reaction mass for a steam cannon
running off waste water from an orbiter.

I'd like to think of a space station as something that has an advantage
in being stationary (as much as something in orbit can be so).  Oh well.

--
<-:(= Anthony Stieber    [e-mail]   uwm!uwmcsd4!anthony

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

Date: 26 Feb 1993 17:29 UT
From: Ron Baalke <[e-mail]>
Subject: Proposed Mercury Mission
Newsgroups: sci.space,sci.astro,alt.sci.planetary

From the "JPL Universe"
February 26, 1993

New way of doing business encourages Mercury team
By Mark Whalen

     It's becoming clear that the catchphrase "faster, better,
cheaper" is more than just a slogan at JPL. It is, indeed, a new
way of doing business, a new philosophy that has now paid off for
a small but ambitious JPL-led team working on a proposed mission
to Mercury.
     The 20-member team -- headed by Principal Investigator
Robert M. Nelson of JPL's Geology and Planetology Section 326 and
11 other Lab staff members -- combines science, engineering and
management disciplines to form the backbone of the Hermes Global
Orbiter mission concept, which was selected by NASA earlier this
month as one of 11 new projects in the agency's Discovery Program
to be funded for additional study.
     Nelson said Hermes was the only JPL project selected (with a
Lab scientist as principal investigator) out of 13 submitted. Lab
staffers are serving as co-investigators on some of the other 10
named by NASA.
     The Hermes mission and the other 10 Discovery class missions
each received $100,000 to support further development and to
"encourage further work," according to Nelson, who added, "It's a
morale booster" that NASA headquarters considered the project
worthy of further investigation.
     The 11 potential projects were selected out of an original
roster of 73 submitted to NASA at a workshop held at the San Juan
Capistrano Research Institute last November. Those selected were
those considered to have the highest scientific value as well as
a reasonable chance of meeting strict budgetary guidelines of no
more than $150 million.
     Nelson said the proposed mission -- with a targeted launch
date of September 2002 -- calls for a single spacecraft launched
by a Delta II rocket to be placed in an elliptical orbit around
Mercury for one Earth year (four Mercury years) after orbital
insertion. With two gravity assists each from Venus and Mercury
to minimize propulsion requirements, the spacecraft would begin
orbiting Mercury in August 2005.
     The mission's goals are to understand Mercury's surface and
interior structure. It would serve as a long-awaited follow-up to
the Mariner 10 flyby mission in 1974, when only half of the
planet was observed.
     "Hermes' first objective," said Nelson, "is to survey and
map the half of Mercury that has never been seen, and then to
determine the surface composition."
     Team member Rosaly Lopes-Gautier, a planetologist in the
Atmospheric and Cometary Sciences Section 324, underscored the
importance of Hermes' proposed objectives by drawing comparisons
to the results from early Mars missions, when "people talked of a
very cratered, moon-like planet. Then when Mariner 9 came along
and mapped the whole planet, it showed that (Mars') northern
hemisphere was totally different. It proved that just because you
have seen half of a planet, you can't assume you can extend your
knowledge to the other half.
     "There could be some considerable surprises on the other
side of Mercury," she said.
     Team member Linda Horn, a planetary scientist in Section
326, added that there are additional incentives to continue study
of the closest planet to the sun. "Radar measurements from Earth
have shown bright regions at Mercury's poles," she said,  "and it
has been suggested that there might be ice deep in the planet's
polar craters, where sunlight doesn't hit."
     Because Mercury is so close to the sun -- an average
distance of 58 million kilometers (about 36 million miles) away
-- protecting the spacecraft's instruments will pose a major
challenge. Plans call for shading devices, insulation and
thermal inertia to protect the spacecraft when the solar
radiation and the thermal flux from Mercury are most difficult to
manage. The mission's payload contains an optical observation
facility, an ultraviolet spectrometer and a magnetometer.
     The mission utilizes a "clever orbital design," said Nelson.
"It will have a highly elliptical orbit, spending a short amount
of time close to Mercury. The spacecraft will take a lot of
science information while it is close to Mercury (and warming
up), and then it will go a great distance away from the planet
and spend long periods of time cooling off and sending back the
data."
     The Hermes spacecraft is one "that has flown many times
before," said Nelson, "but it will be modified to accommodate
Mercury's environment. We will do some instrument modification
also, but that will be done fairly early. In some cases we're
taking instruments that have flown before and making copies of
them.
     "Those are the principal ways we're going to perform the
mission cheaper than in the past," he added.
     The organization of the Hermes team may be the most
interesting facet of the proposed mission. "Most of the time,"
said Nelson, "scientists don't have a major role in mission
development, spacecraft design, ground systems design and
operations planning -- all those things you need to do to fly a
spacecraft.
     "From the start," he added, "we had engineers saying to
scientists, `you just can't do that observation with the
spacecraft and instruments we've got available. Let's think of
another way. '"
     Team member Adriana Ocampo, a planetary geologist in Section
324, said, "I think our team is comprised of `Renaissance-type'
people. We have a lot of different talents, and most of the team
not only has had first hand experience working with flight
projects, but they're scientists who understand the engineering
aspects of a mission."
     "There are a lot of advantages to having a small team,"
added Lopes-Gautier. "People are much more willing to work
together and chip in to do whatever needs to be done, rather than
say, `I'm a scientist; I'm not going to get involved in the
engineering aspects,' or vice versa. This can happen on the
bigger missions."
     In addition, six of the 20 team members are women, "an
extraordinarily high percentage," noted Ocampo.
     "We picked who we thought were the best people, and with the
number of women professionals in physical science at 7 percent, I
was really pleased that this many women were selected," said
Nelson.
     The next step for the Hermes team will come sometime next
year, when NASA conducts a more formal process to determine final
selection of missions to be conducted.
     The other Hermes team members from JPL are San-San Kuo,
Section 326; Arthur Lane, Section 732; Ken Manatt, Section 326;
Ray Morris, Section 317; William Smythe, Section 324; Brad
Wallis, Section 326; James Weiss, Section 326; and Chen Wan Yen,
Section 312.
                              ###
     ___    _____     ___
    /_ /|  /____/ \  /_ /|     Ron Baalke         | [e-mail]
    | | | |  __ \ /| | | |     Jet Propulsion Lab |
 ___| | | | |__) |/  | | |__   M/S 525-3684 Telos | If you don't stand for
/___| | | |  ___/    | |/__ /| Pasadena, CA 91109 | something, you'll fall
|_____|/  |_|/       |_____|/                     | for anything.

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

Date: 26 Feb 93 18:41:34 GMT
From: Josh Hopkins <[e-mail]>
Subject: Refueling Centaurs
Newsgroups: sci.space

[e-mail] (Pat) writes:

>(Brian Stuart Thorn) writes:

>|     Pluto Fast Flyby: Not on that budget, they don't. Hell, they are

>I am glad to know you speak for staehle and the JPL.

He doesn't.  That doesn't mean he's wrong.  There's no way the PFF mission would
get funded if they asked for an on orbit refueling mission.  This is supposed
to be the archetypal "faster, cheaper, better" mission.

>|
>|     It doesn't seem likely to me that in 1994 NASA will decide to launch
>|     a Mars Sample Return Mission in 1995. More reasonably, a big mission

>I believe planners work from what's in hand, not what might be
>done assuming people get some nerve and backbone.  Besides,
>MO and it's sister birds could have planned on it.

Huh? What "sister birds?"


>|     like that will be years in the making (say, 5 at least) leaving
>|     considerable time for developing cryo refueling capabilities. When
>|     we need it, we'll develop it. Hasn't that *always* been the way?
>|     They didn't mate Titan and Centaur until Voyager needed it.

>I think it's easy enough to put a stage onto a rocket.

Then apparently you've never done it before.
--
Josh Hopkins                                          [e-mail]

    You only live once.  But if you live it right, once is enough.
            In memoria, WDH

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

Date: 26 Feb 93 16:59:48 GMT
From: "Kenneth C. Jenks [GM2] (713" <[e-mail]>
Subject: Reliable Source says Freedom Dead, Freedom II to be developed
Newsgroups: sci.space

Allen W. Sherzer ([e-mail]) wrote:
[...]
: Dime a dozen Dennis. Hell, I have friends at the Reston Program office
: who do that to amuse themselves on coffee breaks. Anybody who thinks
: a little about it can save $20 billion or so in life cycle costs without
: breaking a sweat.

: Getting the change implemented, THAT'S the hard part.

:   Allen

Change costs money.  Even if the change saves money in the long run.
Maybe more important is the idea that changing something which has
already been approved implies that the managers who originally approved
it made a mistake, and now you're correcting that mistake, putting egg
on the faces of those going before you.

See quote below.

-- Ken Jenks, NASA/JSC/GM2, Space Shuttle Program Office
      [e-mail]  [phone]

     "Good ideas are not adopted automatically.  They must be driven into
       practice with courageous impatience." -- Admiral Hyman G. Rickover

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

Date: Fri, 26 Feb 1993 17:05:32 GMT
From: Frank Crary <[e-mail]>
Subject: SSF Resupply (Was Re: Nobody cares about Fred?)
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (tomas o munoz 283-4072) writes:
>|> A Titan IV should be able to deliver an extra ACRV. I also don't
>|> see why you couldn't put a few people in that extra ACRV, and
>|> thereby both deliver and retrieve humans.

>I'd like to hea the astronaut office express their views on
>putting crew on top of a Titan IV in a vehicle with no
>manual control capability.

Do you mean vehicles like the Atlas, Titan and Saturn rockets used
to launch astronauts during the 1960s? I don't think manual controls
during a launch add much to safety. Certainly astronauts have been
launched without them (in fact, the Soviets did this exclusively, and
never lost a kosmonaut during launch...)

>|> >How do you perform the actual payload transfer from the expendable
>|> >to the SSF if the SSF is unmanned? - You really need IVA for this
>|> >operation.

>|> Which sort of unmanned: After MTC, you just need to get people to
>|> the station, and there are only a few launches (low risk) before
>|> MTC.

>No, after MTC you still 11 assembly flights and 8 utilization
>flights.  I don't quite understand your definition of low risk.

Perhaps I should be more clear: _After_ MTC, any vehicle which can
deliver a crew to the station (e.g. a crewed, Titan launched ACRV)
can provide transfer expendables to the station. Before MTC, whatever
vehicle transported the crewmen to the station would also need a
week or so of autonomious life support capability (so the crew would
have somewhere to live while transfering cargo.) Therefore, a
crewed ACRV launch would be inadaquate for this task. So, resupplying
the station after MTC should be possible with only Titan IVs. But
before MTC, it would not. Is this inability to resupply the pre-MTC
station a serious risk? Unlike the post-MTC station, this situation
occupies only a short period: To be a problem, the Shuttle would
have to be grounded sometime between the first and sixth construction
flight, as opposed to any time over a thirty-year period for the
post-MTC situation. Therefore, the problem of supporting the
pre-MTC station without the shuttle is less likely. Second, the
pre-MTC station represents an investment of only a few launches. If
the shuttles were grounded, and the pre-MTC station lost, it wouldn't
be a complete disaster: The few elememts lost could be replaced.
Therefore, the costs and probability of pre-MTC station loss are much
lower than those of the post-MTC station; a back-up resupply system
(to guard against shuttle failure/groundings) which would only
work after MTC still gurads against the bulk of that risk.

                                             Frank Crary
                                             CU Boulder

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

Date: Fri, 26 Feb 1993 17:32:37 GMT
From: fred j mccall 575-3539 <[e-mail]>
Subject: SSF Resupply (Was Re: Nobody cares about Fred?)
Newsgroups: sci.space

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

>As was noted, Shuttle sized payloads can go up on Titans in the
>short run. As for the thruster modules, since they are swapped
>out every 180 days, it would be a simple matter to *add* valving
>and fittings to a replacement pack to allow on orbit fueling at
>any time. We aren't locked in to module replacement for the entire
>30 year life of the station. If the Shuttle replacement can't
>convienently recycle thrusters, we can easily modify them not to
>require recycling.

And how much is *that* going to cost?  Ever heard the phrase "Do it
right the first time"?

>Since we *are* counting on Shuttle for the
>short run, there's no reason to incur the upfront costs of modifying
>off the shelf thruster packs now.

'Off the shelf thruster packs'?  Are you telling me that these are
some kind of standard item; on-orbit replaceable thruster packs?  Why
is it that that just sounds questionable to me?  If they're 'off the
shelf' now, it's because of the design decision to use them, I would
think.

--
"Insisting on perfect safety is for people who don't have the balls to live
 in the real world."   -- Mary Shafer, NASA Ames Dryden
------------------------------------------------------------------------------
[e-mail] - I don't speak for others and they don't speak for me.

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

Date: Fri, 26 Feb 1993 17:33:16 GMT
From: Joe Cain <[e-mail]>
Subject: The NASA Budget Myth
Newsgroups: talk.politics.space,sci.space

In article <[e-mail]> Dr. Norman J. LaFave <[e-mail]> writes:
>
>                                AMOUNT       FY 1993 OUTLAYS
>                              (BILLIONS)   (PERCENT OF BUDGET)
>
> 2. DOD Military and Civilian           317.0           19.1
>
>What NASA gets                           14.2            0.85
>
>.. concentrating on NASA and other civilian science
>appropriations as your main target for cutting the deficit is
>ridiculous..

I agree. Now how do we go after DOD?


Joseph Cain        [e-mail]
[e-mail]        scri::cain
[phone]        FAX [phone] or -0098

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

Date: 26 Feb 1993 17:31 UT
From: Ron Baalke <[e-mail]>
Subject: Ulysses Mysteriously Shuts Down
Newsgroups: sci.space,sci.astro,alt.sci.planetary

From the "JPL Universe"
February 26, 1993

Ulysses mysteriously shuts down
By Diane Ainsworth

     The Ulysses spacecraft mysteriously shut its science
instruments off and stopped sending data to Earth on Feb. 14,
leaving ground controllers incommunicado for more than five
hours.
     The problem, which has occurred once before, was considered
"a glitch" by the Ulysses' operations team, not too serious but
also not minor, because the cause of the anomaly was unknown.
     "Certainly (the anomaly's) effect on mission operations is
serious, because it took several days to get everything back up
and running," said Peter Beech, European Space Agency (ESA)
mission operations manager for the ESA spacecraft. "But we're 99
percent back to normal now, and the spacecraft is performing
perfectly."
     Ground controllers spent three days turning the spacecraft's
science instruments back on, said Donald Meyer, NASA's deputy
mission operations manager at JPL. All but one instrument -- the
Solar Wind Ion Composition (SWIC) experiment -- were fully
operational as Universe went to press. SWIC operates at high
voltage and required several days of incremental voltage
increases before it was operating normally, Beech said.
     The spacecraft was being tracked by the Deep Space Network
antenna near Madrid, Spain, when the anomaly occurred at about
4:50 p.m. PST Feb. 14. The spacecraft went into a safe mode,
shutting off all instruments and switching to a backup radio
transmitter.
     Engineers continued to receive Ulysses' radio signal, but
received no science data or telemetry about the spacecraft's
condition and performance. New commands took about 40 minutes to
reach the spacecraft, Beech said. Science data and engineering
telemetry resumed five hours and 10 minutes later.
     An investigation of the problem has begun, although
operations team members are not optimistic that an answer will be
found.
     "We investigated this the last time it occurred in June 1991
and never reached a conclusion," Beech said. "The anomaly could
have been anything -- transient events out in space or onboard
the spacecraft. I don't think this is anything that we will be
able to identify positively."
     Ulysses, a joint NASA-European Space Agency mission to study
the poles of the sun, is about 18 degrees south of the ecliptic
plane, slowly looping its way back toward the sun. The spacecraft
will begin its primary mission in June 1994, when it starts a
four-month pass over the sun's southern pole.
                                    ###
     ___    _____     ___
    /_ /|  /____/ \  /_ /|     Ron Baalke         | [e-mail]
    | | | |  __ \ /| | | |     Jet Propulsion Lab |
 ___| | | | |__) |/  | | |__   M/S 525-3684 Telos | If you don't stand for
/___| | | |  ___/    | |/__ /| Pasadena, CA 91109 | something, you'll fall
|_____|/  |_|/       |_____|/                     | for anything.

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End of Space Digest Volume 16 : Issue 241
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