Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V15_5/V15NO576.TXT

Internet Message Format | 1993-07-13 | 35KB

Date: Mon, 21 Dec 92 05:01:17
From: Space Digest maintainer <[e-mail]>
Reply-To: [e-mail]
Subject: Space Digest V15 #576
To: Space Digest Readers
Precedence: bulk


Space Digest                Mon, 21 Dec 92       Volume 15 : Issue 576

Today's Topics:
                     Aerospike engines/SSTO/DC-?
                           DoD launcher use
                 Justification for the Space Program
    MOL (was Re: Terminal Velocity of DCX? (was Re: Shuttle ...))
      People who can't count costs (Was Re: Terminal Velocity of
       Terminal Velocity of DCX? (was Re: Shuttle ...) (4 msgs)
                            What is DC ??

    Welcome to the Space Digest!!  Please send your messages to
    "[e-mail]", and (un)subscription requests of the form
    "Subscribe Space <your name>" to one of these addresses: listserv@uga
    (BITNET), rice::boyle (SPAN/NSInet), utadnx::utspan::rice::boyle
    (THENET), or [e-mail] (Internet).
----------------------------------------------------------------------

Date: 20 Dec 92 06:19:00 GMT
From: [e-mail]
Subject: Aerospike engines/SSTO/DC-?
Newsgroups: sci.space

On the subject of DC-? , SSTO and Aerospike Engines the following
observation could be made to the question Why Aerospike Engines
are not used.

Lets make an assumtion here that the military has a super secret
spy plan (Aurora?) that can go (atleast) mach 8 to 10.
An engine such as this would need to be built to support a SSTO
vehicle. The military could not have some non classified project
stumble on their working design. What then is the goal of the
military as it comes to SSTO research?

The military will oversee the research in this area. Any designs
which could work (or would lead to the program developing the
same engine) will be discouraged or lobbied as non workable
designs. In short the objectives of the military is to assure
that this country does not have a working civilian SSTO craft.

or atleast thats how I see it

Bob

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

Date: 21 Dec 92 02:36:26 GMT
From: Brian Stuart Thorn <[e-mail]>
Subject: DoD launcher use
Newsgroups: sci.space

>we should look to develope cheap sats to go with DC-1.
>
   I thought we were already developing cheap sats, but these are to
   go up with Pegasus, Taurus, etc.

   -Brian

-------------------------------------------------------------------------
Brian S. Thorn                                    "If ignorance is bliss,
[e-mail]                               this must be heaven."
                                                -Diane Chambers, "Cheers"
-------------------------------------------------------------------------

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

Date: 21 Dec 92 04:32:00 GMT
From: [e-mail]
Subject: Justification for the Space Program
Newsgroups: alt.rush-limbaugh,talk.politics.space,sci.space

In article <[e-mail]>, [e-mail] (Paul Dietz) writes...
>In article <[e-mail]> [e-mail] writes:
>
> >>Much more believable results have been obtained by actually studying
> >>specific resources here on earth.  When you do that, and when you take
> >>into account technological improvements, the idea that things are
> >>going to necessarily go to hell just evaporates.
>
> >Believable by whom? You? Well all of these extrapolations and any belief in
> >them are acts of faith. You believe what you choose. Sophmore calculus teaches
> >the fallacy of extrapolating a value beyond the known data point.
>
>Believable in the sense that they are grounded in actual study
>of physical reality, not airy untestable abstractions.  For example,
>going out and actually studiny geological abundance, and demand
>for, various elements.

We have been through this little discussion here before. Mining, versus
planetary geology is the study of the abundance of desirable minerals in
concentration, not percentage of planetary mass. If you look at any
statistical survey of the concentration, or in economic terms, economically
justifiable available resources, you will find that there are very
few left.

We are doing better at getting economically viable deposits of poorer and
poorer ore, the caveat to this is that the cost of processing increases
the overall cost and the pollution (slag from the reduction process, chemical
pollution freed by the reduction process) also increases relative to the
return in refined metals. This is why you see very few open pit copper mines
in the US or Iron mines for that matter anymore. Even though Iron is one of
the most abundant metals known in the universe, the problems of extraction
from sulfer based ores make it unattractive to commercially mine.

>
> >>The 1500 year figure you present is a figment of your imagination.
> >>Come on -- technology is going to be rather different by the time the
> >>year 3500 rolls around, space exploration or not.  You can't possibly
> >>have any idea what technology will be like even 100 years down the
> >>road, let alone 1500.
>
> > Yes technology will be a lot lower, if we let those who are vigorously
> > promoting a turn from technology development to get the upper hand.
> > Doubt this you do?
>
>Yes, I doubt it.  The idea that we're going to get locked
>in some sort of technological stasis is a bizarre fantasy.  Technology
>is continuin to advance smartly.

Take a look around you my friend, read this very news group. Technology is
being sacrificed on the holy grail of defict reduction due to the fact that
the consitutancy is small relative to the bread and circuses that keep
Congress critters in office. Expect to see cuts also in medical research that
are disguised as "cost cutting" and "unnecessary expenditures".

>
>Of course, if you've made the bad decision to go into an area with a
>doubtful future -- like defense, or space, or fusion -- you might see
>things differently.
>

Nice little subtle cut here. For your information I am from the commercial
computer industry. The PC you are using is probably based on the designs that
one of the companies that I worked for developed. I left that industry and
the considerable money that I was making due to the fact that it is in the
aerospace industry that is expanding the economic reach of mankind from this
little dirt ball that the most good can be done.

>
> >>The fundamental limit to resource exploitation is imposed by
> >>availability of energy, and space exploitation is *not* needed to get
> >>essentially inexhaustible supplies of that.
> >
> >Oh really? Tell us how you intend to accomplish that? No one else has.
>
>Endless people have, wingnut!  It's called fission.  There is sufficient
>uranium and thorium in the earth's crust to supply current levels
>of primary energy consumption for billions of years, if used with one
>of the several breeding cycles.  Moreover, there is enough fossil
>fuel around that we needn't go to fission right away.
>

Ad hominum attacks aside, I submit that your thesis here is incorrect. I know
what fission is and one of the largest plants of that type are within a few
miles of my present location. Unfortunately the contractor scum that built
it for TVA's nuclear program did such a poor job that it took over a billion
dollars just to straighten out all of the defects (Browns Ferry). I agree that
fission is a nice, relatively safe form of energy production. It is also
very expensive. Each plant costs somewhere in the 5-8 billion dollar range.
Bellefonte nuclear plant a few miles from here in another direction will cost
almost a billion dollars just to finish from its 80% percent complete state
it currently is in. All in all my region of the country has more nuclear
power than any region in the Americas and let me inform you that my power
bill is anything but cheap.

>The idea that we are near some sort of irretrievable collapse due to
>exhaustion of energy sources just doesn't have any basis in fact.
>

I never postulated that we are going to have an irretrievable collapse. My
postion is that we will have as a planet, a much lower standard of living
than the Western nations do today, due to pressures of population and
pollution. A fossil fuel based world economy simply cannot support the
legitmate desire of third world nations to grow and have a better standard
of living. Ever been to Taiwan Mr. Dietz? Well it is a wonderful place but
it smells, pollution is terrible. The Taiwanese people are paying a price
for their industrialization. From what I hear from other who travel in the
world, the same is true in most places, especially in the orient and the
former Soviet Union. There are whole tracts of the breadbasket of Asia
where children learn of birds and trees from videos and books because the
radiation from your fission plants has rendered outside living impossible
>
> >if we get cheap fusion we can drive the cost of energy way down. Too bad we
> >are a long way from that. The demand for energy to support a world population
> >at a standard of living comparable to the industrialize nations would mean
> >a two order of magnitude production increase in the supply of energy, and
> >material resources, with it's attendant pollution, both chemical and thermal.
>
>Get your arithmetic straight.  Current world energy consumption is
>about 350 exajoules per year.  In the US, we consume about 3x10^11
>J/year/capita.  A population of 10^10 consuming energy at our level
>would increase demand about 1 order of magnitude.  If they consume
>energy at the level of, say, current europeans, the demand would be
>lower.

I am glad you detected this in my calculation. It is always nice to leave a
teaser like that to get a response. What if we in the US want to increase
our own energy consumption? Face it fossil fuels are not going to last forever.
Pollution in many American cities is so bad that the sky is brown for most
of the year instead of blue, (Can you say Los Angeles?) Governments are
mandating that we begin to switch to electrical power for our automobiles. This
is a good trend in my opinion. That will drive up the demand for electrical
power by several orders (at least two) of magnitude. Where is that energy
going to come from? Your fission plants? Not hardly, while this is a good
solution on an interim basis it is not the desired solution. At a cost of
5-10 billion each we would have to build at the very least an order of magnitude
more plants than we have today. Today we have 72 operating Nuclear plants in
the US. This means that say 700 new plants. (By the way last I heard Nuclear
power was supplying 12% of our electrical energy. Multiply the number of
plants by a median price of 7.5 billion each and you come out to roughly
550 billion dollars for just the plants.

>
>Direct thermal pollution at this level would not be of global importance.

>Chemical pollution?  There's no law of nature that says chemical
>pollution cannot be reduced as far as we like.  Certainly replacing
>fossil fuels with nuclear-derived energy sources would reduce
>this pollution greatly.

No there is no law of nature that says chemical pollution cannot be reduced.
The law against this is one of economics. We could simply heat up the
chemical pollutants till the fractioned into their atomic constitutents.
However this would require another order of magnitude increase in electrical
generation. How much do 7000 nuclear plants cost? That is just for the US by
the way.  Also the mining of Uranium and thorium is a costly, polluting
process. The abundances are very low for these materials. The demand is down
now due to an abeyance of nuclear weapons building. The weapons industry
fostered a huge infrastructure to support the reduction and refining of
these fissionables. In Oak Ridge Tennessee there is a fossil fuel power plant
(Bull Run) just to supply the power to the installations at the Oak
Ridge plants where these materials are processed. Have you ever been around
slag heaps? Or around areas that are marked off as no tresspassing because
it is deadly to walk around in the woods where this material is buried? I have
Go to Lenoir City Tennessee and go to the Melton Hill Damn. Then try to climb
up the hill on the East side of the river and see how long you live.

>
> >To blithly deride the space option by pointing to technology tha does not
> >exist or is even on the horizon is irresponsible.
>
>Breeder reactors exist today.  The technology for reprocessing
>nuclear fuel exists.  Better, cheaper technologies for this are
>in the works (the pyroprocess being developed at ANL, for example).
>They are not moving faster because we have such an embarrassing
>glut of energy.
>

We have a so-called glut of energy today because Arabs have enough brains
not to repeat the mistakes of the 1970's oil shocks. All they have to
do is keep the marginal costs of oil slightly below the costs of alternative
energy sources and they keep us hooked on the habit of fossil fuels.
There is an Arab proverb that says:

My Grandfather drove a camel
My Father drove a car.
I drive a jet
My son flys in space
His son will drive a camel

It is apparant that you, as most Americans have little concept of the
global realities of energy production, usage and politics.

>So-called "renewable" resources are less well developed, but
>are on a steeper learning curve.  We can expect them to get cheaper
>as well,
>

We have reached the limit on hydroelectric in the US. Geothermal is
of limited use and very polluting. Wind power also is of limited use
and confined to areas with high wind velocity. Alcohol production for
energy consumption is more expensive and energy intensive than simply
using more oil. What processes do you mean? solar? Well let me inform
you that there are no solar R&D efforts outside the aerospace industry.
Those are faring badly at this time as well. Boeing has halted work on the
37% efficiency concentrator cell. We are the only ones, at this time, keeping
the 26% efficient planar technolgy alive, and we are doing for space
applications!

>To baldly proclaim that space is essential, when it's orders of
>magnitude away from being competitive, and when multiple alternatives
>exist, is irresponsible at best, and (if coming from one feeding
>at this particular trough) banal at worst.
>

As I have shown here, simply in production costs, your nuclear alternative
is more expensive than setting up a translunar space transporation
infrastructure. Nuclear power is barely competitive and no plant has been
licensed since 1978. The costs of nuclear power has crippled many power
companies and paying of the construction bonds for plants is directly the
cause for high utility rates in many parts of the nation.

At this time I do work in the space arena. I do this of choice not of
necessity. I do this because it is the key to the future. Tomorrow I can
return to my commercial computer world and make a great deal more money than
I do here as a student. I took a seventy percent cut in pay to change to
this field. Have you the cjonies to do this for what you believe?

> >Captial formation means wealth. This has been the driver of civilization for
> >at least four thousand years. Where there is wealth there is plenty. In the
> >past, wealth generation has come in Three ways:
> >
> >Natural resource explotiation
> >Economic activity redistributing the wealth to the more productive
> >War and conquest
> >
> >The only truly platible, long term solution to the problem of not
> >enough wealth is clearly option one. Option two breeds option three by
> >the jealousy endengered by the winner of the economic war. (Remember
> >Japan went to war with the US because we were denying them natural
> >resources, "economic sanctions")
>
>Complete and utter crap!
>
>The most important driver of wealth creation is accumulation
>of *knowledge*.  Economies can and do grow, and people get
>wealthier, in the absence of increases in resource exploitation.
>

Go study your history books for a while there Paul. Knowledge did not
help the Egyptians, Greeks, Persians, Romans, Chinese, or any other civilization
in history. It has always been the accumulation of wealth either by conquest
of arms or by economic competition. Knowledge is very important, but in and
of itself is no solution. The knowledge of Rome did not suffice to stem
the tide of the Celts. The superb knowledge and organization of China and
Persia did nothing to stop the lances and military genious of Ghengis Ka Khan.

Almost every great civilization of antiqity grew strong through the conquest
of their more advanced neibhors and through the aquistion of their wealth.
the pursuit of knowledge for knowledge's sake is mostly a modern phenomenon.
The greater acquistion of knowledge as done nothing to aid the United States
in its current troubles. America is bleeding its wealth away because we
are not investing in technology to create wealth. We create wealth by
creating new technologies and creating demand where there was none before.
This was true of the car, the plane, the electricity that we use every day.
We are falling behind because many of us have bought the economic postulate
that we can redistribute the wealth of the world more to our liking. This
only takes from others to add to us. This is how the rest of the world has
done the United States. The cars we made the best are now made in Japan,
the electronics as well. It is better if we advance forward and make new
technology and create new demands rather than fight for market share that
has been the cause of many wars in history.

>
> >Sorry Paul but go to any freshman chemistry class in college today and listen
> >to the litany of scarce resources. We are still going forward because we are
> >taking resources from the third world. What happens when those are gone?
> >What happens when the third world wakes up and says that they are gonna keep
> >their resources to fuel their own climb to prosperity?
>
>Then we go to lower grade deposits, or use substitutes.  You are
>repeating the Malthusian nonsense here (along with a line of
>politically silly gibberish about exploiting the 3rd world.)
>

Have you ever traveled outside the US Paul? I think I have answered your
little littany on the lower grade deposits above. On the third world
part, have you ever read newspapers from abroad? They say things that your
politically correct CNN does not like to show, such as how multinational
corporations are systematically taking the resources of much of the third
world. It would be ok if the money was kept in the country, but alas in
many instances it is not and the money that is kept only goes to keeping
the few and the rich in power. Read a little bit about Africa sometimes.

>The third world "waking up": just why do you think they're selling
>their resources?  Because you can't eat copper or cobalt, and, absent
>the real drivers of wealth -- a knowledgable population backed
>up by accumulated capital -- these resources are just useless lumps.
>

The answer that a third world person would give you to that is that the
west does not provide the right type of help. It is ok to feed people
overseas. It does much to make Westerners feel good about themselves and
how they are helping the starving masses. What is lacking is teaching those
people how to help themeselves. There is no way to accumulate capital if it
is being exported by the corporations that exploit the countries natural
resoruces. There is no way to build a knowledgeable population when you have
to hold out your hand to the west just for food to eat. Many African countries
have few books for their schools. We in our groups send books on science
and astronomy that are thirty years old and are thanked for the help. This is
the type of assistance these people want. If we are truly responsible we want
those people to be able to stand up and do for themselves. There is an old
proverb that is very true here.

Give me a fish and I eat for today
Teach me to fish and I eat for a lifetime

This is the kind of help the third world needs to get them out of the
endless cycle of begging for us. This will of course put them on the
path of using more energy that needs to be generated somehow. Also the day
will come that they need the resources we are taking out to the ground in
their nations. No amount of knowledge will build a nation if their are no
natural resources to provide a source of wealth.

>To get specific, just which resource are you talking about?  I tell
>you what: you mention one, and I'll demonstrate that we can either
>tolerate price increases (because so little is used), can find other
>sources, or can substitute.
>
>    Paul F. Deitz

Oh lets start out with Platinum. I currently costs over 500 dollars per ounce.
Some is needed for each catalytic converter in the world. Many pound are needed
each week to be put in the converters. (The converters are built near here and
there is a Brinks truck that comes to deliver the platinum every week or two)
Platinum is one of the essential catalysts for industrial processes relating
to lowering the chemical energy needed to make many processes work efficiently.

We can recover much of the catalyst used but there is always some loss. To mine
your lower quality ores we need either more platinum or its analog or very
expensive vapor phase processes. Where we gonna get it? Let me tell you where.

In observations of Asteroid 1986 DA radar evidence pointed out that it
very probably a metal asteriod. The size of this asteriod is around 2 km.
It is estimated that there is 1 trillion dollars worth of platinum and 90
billion dollars worth of gold on this one object.

What about gold? Well the major use of gold is not in jewelery but in industry.
We currently use vast amounts of gold in electronics to plate connectors.
Yes yes I know we can use substitues but the very nature of a substitute
is that it is in most cases inferior. This is certainly true for connectors
plated with anything other than gold. Also gold has many other uses that it
could be used for if it were not so expensive relative to its inferior
substitutes.

What about copper? Yes yes I know that we can substitute aluminum for copper in
most cases but aluminum is only 90 as efficient as copper at carrying electricty
This translates into a 10% decrease in the net efficiency in most of our
power generating and distribution system. If copper were cheaper (more abundant)
then we could save billions per year just in this area.

What about stainless steel? This has been commented on here before but I'm
gonna bring it back up. If the cost of stainless were 1/100 of what it is
today, we could build bridges with it that would last for centuries rather
than for decades. Since the last round of this discussion, I have spoke with
Civil engineers (I am an ASCE (American Society of  Civil Engineers) member)
and they would love to have stainless. The more difficult workability would
more than be offset by the lower operating costs that such bridges entail. Most
bridges that are steel, such as the Golden Gate must be constantly painted and
buffed and treated to stop or slow down corrosion. This is a very expensive
process. In modern steel and iron Zinc coating helps for a while, but also
adds to pollution of the soils by heavy metals.

You might come back and talk about he advances in superconductivity and how
they will help in the electrical field. Yea they might execpt that the
yttrium that is essential for the superconductors is extremely rare and the
reduction and refining of this metal is very polluting.

Well this is enough for the moment. There are many other areas where the
resources of the entire solar system would do great good in raising the
standard of living of our nation as well as the world. I have not even spoken
on broadcast power, and the lowering of costs and pollution that would come
from extraterrestrial reduction and refining of metals. All we need is a
transporation infrastructure. Give us 150 billion and we will change the
face of the world. Your way has been tried for the last twenty years. Your
way was the professed need that caused funding to be terminated for the
Apollo program. Your way is a failure. Look around you at the crime and
poverty your bread and circuses programs have fostered. Look around at your
dead nuclear power program. Look around.

Dennis, University of Alabama in Huntsville

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

Date: 20 Dec 1992 18:37:12 GMT
From: Pat <[e-mail]>
Subject: MOL (was Re: Terminal Velocity of DCX? (was Re: Shuttle ...))
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Hartmut Frommert) writes:
>[e-mail] (Edward V. Wright) writes:
>
>>You heard wrong.  One MOL flew (unmanned).
>
>Could somebody provide data ?




According to a friend of mine who was a MOL engineer.  One MOL flew
Manned.  only it was called ASTP.

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

Date: 21 Dec 92 02:30:52 GMT
From: Brian Stuart Thorn <[e-mail]>
Subject: People who can't count costs (Was Re: Terminal Velocity of
Newsgroups: sci.space

>The flight rate by the way oh thou ignorant of basic math is 8 this year
>with four flights scheduled in the first four months of next year. It is
>beginning to be obvious that the flight rate of 8 per year is more of a
>political than technical nature. If you were to account in this manner
>the costs are even lower.

   I don't think the Congress convened and said "NASA can't fly more
   than eight missions per year". Actually, the eight-per-year (seven
   on the slate for '94) is more of a 'let's not press our luck'
   decision than a 'can we justify more than eight a year' decision.
   NASA occassionally cites fuel costs as being involved, but that's
   hooey, IMHO. I think they are staring down that long dark one-
   failure-in-25-flights statistic and thinking 'let's not push
   the flight rate any more than we have to.' Wise decision, I'd say.
   If you ask me, they should fly Shuttle sparingly until Freedom is
   ready to launch, and then accelerate to 12 flights per year.
   That's one per month, a track record that they've demonstrated
   several times in the past few years, and are about to again, as you
   noted, from December '92 to April '93 (with only 3 Orbiters, BTW.)

>ONLY if you take every single budget item in the entire NASA budget that has
>any relationship to manned space activities and then divide by the number
>of flights per year, then you will get a >$500 million per flight costs.

>Dennis, University of Alabama in Huntsville

   It basically comes down to a point of what one considers
   operational costs and what one considers related costs. On the
   operational side, counting Launch Control, OPF engineers, and
   fuel costs, Shuttle is still the most expensive. Of course, nothing
   else has to launch human beings, so comparisons are very tricky.
   On the related costs side of the budget, with the exception of the
   DC Revolution endlessly touted here on the net, new launch systems
   will still need major launch facilities (and standing armies), big
   computerized Mission Control Centers, and numerous contractors. These
   things are counted in Shuttle budgets, but not in Titan IV, NLS,
   or Spacelifter budgets. Of course then, the others look mighty
   cheap.

   I myself have given up the idea of comparison/contrast of launch
   vehicle costs, it's a Kobayashi Maru scenario if there ever was one.
   Instead, I'll let McDAC prove they can do it cheaper than Shuttle,
   since the DC-1 is the only thing on the drawing boards with similar
   objectives (sending up humans and payload and bringing them back.)

   -Brian


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

Date: 21 Dec 92 04:58:59 GMT
From: Greg Moore <[e-mail]>
Subject: Terminal Velocity of DCX? (was Re: Shuttle ...)
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Pat) writes:
>In article <[e-mail]> [e-mail] (Greg Moore) writes:
>>
>>    Given a figure of $500 Million a flight, useful work can be:
>>10 hours/day * 6 astronauts * 5 days = 300 hours.  Divide this into the
>>above number nd you get $1.6 Million.  If this is a EDO flight of 10
>>days, your on-orbit costs drop in half.  So, I'd assume that
>>
>
>
>I think your number is a tad optimistic.  I think the shuttle suits
>are only good for 4-5 Hours, before a recharge is done.
>Also While you have a crew of 7,  at least two would stay in board.
>The pilot and the Arm operator (He may need an assistant).
>Henry is the roving expert on this.  so I get.
>(oops,  also i guy stays suited up in the airlock  as an emergency helper.
>8 hours/day (2 suit sorties) * 4 astronauts * 5 days = 152 hrs.
>Less if you need another guy on the flight or middeck.
>so i ball park it in at 3.5 million/hour.  not counting additional
>depreciation on the suits.
>
>I would imagine the CIS is still making a killing at 5 million/hour.
>

    When I posted the above, I was assuming on-orbit time in
general.  It was only after I wrote that did someone point out that
the original reference was to Soviet EVA time, not plain old
on-orbit time.

    I would pick a few nits with your numbers though.
7 hours of work appears to be max.  That was about what they did on
the IntelSat Rescue.  The airlock will hold 3 suited astronauts, and
this is a tight fit.  So this means to get 4 our at a time, you'd have to
recycle the lock twice.  That gets tough on air supplies.
    BUT, I think the point is kinda moot.  So far a lot of the
work taht people want done, is in a pressurized environment:Spacelab,
SpaceHad, mid-deck experiments, etc.  The need for EVA time is much lower.

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

Date: 21 Dec 92 02:31:29 GMT
From: Brian Stuart Thorn <[e-mail]>
Subject: Terminal Velocity of DCX? (was Re: Shuttle ...)
Newsgroups: sci.space

>In article <[e-mail]> [e-mail] (Greg Moore) writes:
>>
>>       Given a figure of $500 Million a flight, useful work can be:
>>10 hours/day * 6 astronauts * 5 days = 300 hours.  Divide this into the
>>above number nd you get $1.6 Million.  If this is a EDO flight of 10
>>days, your on-orbit costs drop in half.  So, I'd assume that
>>
>
>
>I think your number is a tad optimistic.  I think the shuttle suits
>are only good for 4-5 Hours, before a recharge is done.
>Also While you have a crew of 7,  at least two would stay in board.
>The pilot and the Arm operator (He may need an assistant).
>Henry is the roving expert on this.  so I get.
>(oops,  also i guy stays suited up in the airlock  as an emergency helper.
>8 hours/day (2 suit sorties) * 4 astronauts * 5 days = 152 hrs.
>Less if you need another guy on the flight or middeck.
>so i ball park it in at 3.5 million/hour.  not counting additional
>depreciation on the suits.
>
>I would imagine the CIS is still making a killing at 5 million/hour.
>

  Nope, not overly optimistic. Several Space Shuttle astronauts have
  spent seven hours or more in the EVA suits without recharge. Most
  recently this was done on the STS-49 mission, during which three
  crewmen spent over eight hours in their suits before recharge.
  I think six hours is considered a baseline EVA, though.

  -Brian


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

Date: 21 Dec 92 02:32:05 GMT
From: Brian Stuart Thorn <[e-mail]>
Subject: Terminal Velocity of DCX? (was Re: Shuttle ...)
Newsgroups: sci.space

>Here seems a stupid one?
>
>SVS needed a clear payload bay in order to test full arm extension.???
>
>Now when a satellitte is carried up, it is inside some shrouds and often
>a turntable spinner.  Also bigger payloads are on racks.
>
>Why not towards the last day of flight,  EVA two astronauts and jettision
>the miscellaneous hardware.?  sure it's sapce junk,  but they could
>wrap it all together on some cables and deploy a large mylar drdrogue
>shield so it's radar visible and has high atmospheric drag.  it should come
>down in a few years, if the drag is sufficient.
>
>any guesses?


  No, that's not a very good idea. We don't need more Space Junk floating
  around up there no matter how easy it is to see.

  On the other hand, when a TDRS/IUS is sent on it's way, it opens up
  a great big space in the payload bay. Plenty of room for the RMS
  Space Vision System's needs. So, if it needs a clear payload bay for
  tests, fly it on STS-54 (TDRS-F/IUS) or STS-51 (ACTS/TOS). I don't
  understand how this idea escaped the person who replied to my original
  post.

  -Brian


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

Date: 21 Dec 92 02:35:51 GMT
From: Brian Stuart Thorn <[e-mail]>
Subject: Terminal Velocity of DCX? (was Re: Shuttle ...)
Newsgroups: sci.space

>Here seems a stupid one?
>
>SVS needed a clear payload bay in order to test full arm extension.???
>
>Now when a satellitte is carried up, it is inside some shrouds and often
>a turntable spinner.  Also bigger payloads are on racks.
>
>Why not towards the last day of flight,  EVA two astronauts and jettision
>the miscellaneous hardware.?  sure it's sapce junk,  but they could
>wrap it all together on some cables and deploy a large mylar drdrogue
>shield so it's radar visible and has high atmospheric drag.  it should come
>down in a few years, if the drag is sufficient.
>
>any guesses?


  No, that's not a very good idea. We don't need more Space Junk floating
  around up there no matter how easy it is to see.

  On the other hand, when a TDRS/IUS is sent on it's way, it opens up
  a great big space in the payload bay. Plenty of room for the RMS
  Space Vision System's needs. So, if it needs a clear payload bay for
  tests, fly it on STS-54 (TDRS-F/IUS) or STS-51 (ACTS/TOS). I don't
  understand how this idea escaped the person who replied to my original
  post.

  -Brian


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

Date: Mon, 21 Dec 1992 07:09:17 GMT
From: Hugh Emberson <[e-mail]>
Subject: What is DC ??
Newsgroups: sci.space

>>>>> On Sat, 19 Dec 1992 01:59:04 GMT, [e-mail] (Henry Spencer) said:

Henry> Note that Atlas did it with a stage and a half -- dropping two
Henry> engines but nothing else -- in 1958.  Using 3000m/s exhaust
Henry> velocity, too.

How did Atlas drop its engines?




--
Hugh Emberson -- CS Postgrad
[e-mail]

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

End of Space Digest Volume 15 : Issue 576
------------------------------