Conference 7.286::space

    Flying shuttles in order:
    
    	1.  Enterprise (not spaceworthy---flew only approach and landing
    tests by being dropped of a 747 at n-thousand feet)
    
    	2.  Columbia  (the first shuttle in space)
    
    	3.  Challenger
    
    	4.  Discovery
    
    	5.  Atlantis (has made only a few flights.  3 or so?)
    
    Burns
    

    
    	There is also 
    
    	6.  Phoenix (estimated year of completion, 1991)
    
    	BTW, Rockwell is ahead of schedule on Phoenix.
    
    

    They've named Challenger's replacement "Phoenix"?!?!?!
    
    I'm not sure...that's either _real_ bad or _real_ good.......
    
    
    				-Jeff

    The latest I heard was that it was to be named by a contest among
    school children.  (Seems appropriate to me...get them involved again,
    hopefully with less traumatic results.)
    
    Burns

    Burns is right.  There was a small AP blurb Sunday about the
    contest, to be held sometime during 1988.  No other details,
    like what the winner gets.
    

    
    uh....then if the contest is to be held in 1988...then the new shuttle
    has not been named yet?
    
    			-Jeff

      I think the answer to the original question is "Not enough." With
    any other large aircraft type, like the B1 or 767, they usually
    build 3 or 4 prototypes which fly 100 or mor test flights then they
    start building production models. Seeing as how the shuttle is much
    more complicated than something like the b1 or 767, the same should
    be done here.
    
      One or two Shuttle B's should be built and flown then 10 to 15
    shuttles should be built. It this was done, it would work as originally
    planed and would be able to support the Space Station, Comercial,
    Scientific, and Military needs with little problem.
    
      This sounds like it would cost a lot but I don't think it would.
    Production models always cost less than prototypes. The benifits
    would be enormous.
    
      George

    
    Re: .7
    
    	But if we made 10-15 shuttles, that would take *so* much of
    NASA's budget that building expendable vehicles would have to be
    stopped.  That gives us a total reliance on the shuttles as our
    only launch vehicles and if *they* are grounded for a while, we
    would be, well, in the exact position we are now -- dead in space.
    
    	Using a shuttle to go up and kick a satellite overboard is like
    using a Ferrari to go grocery shopping.  (How many bags of groceries
    can you fit in a Ferrari anyway? :-)  Use the shuttles for what
    they are good for -- taking people and cargo up when the cargo *needs*
    the people along.  Most payloads can go up more cheaply, albeit
    less glamorously, on expendables.
    
    							-craig

      There is no reason for the shuttle to get grounded for a long
    time. There was a time a few years back when DC-10s were falling
    out of the sky like rain but they were only grounded for a few
    months. Now, if a shuttle is lost we go from 4 to 3. They have
    to stop flying because a couple more loses and there is nothing
    left to fly. If there were 10-15 shuttles, and if we lost a few
    the others could still fly. This is what the airlines do and noone
    seems to mind.
    
      With that number of shuttles, access to space would be frequent
    and relyable enough for comercial applications and private money.
    As space applications effected more people directly, there would
    be more interest in space and more money for NASA.
    
      This would benifit scientific users as well. Say that scientific
    users get 15% of NASA's current budjet. If they only got 5% of a
    budjet that was 10 times as large that would be an increase.
    
      That kind of growth seems possible with 10 or 15 shuttles. With
    only 4 it will always remain a prototype system (like the 4 b1's
    during the Carter years). In spite of what people are saying, I
    doubt that 4 shuttles running with 3 year delays everytime one
    blows up will be able to support much of anything much less a
    space station.
    
      George

    
    	You and I agree on the bottom line that the current lift capacity,
    even if the shuttles were flying, is too low.  I still believe that
    ELVs in conjunction with the shuttles is the best mix due to the
    economics.  No matter how many shuttles are made, the "price per
    ton to orbit" of real payload is going to be higher than for ELVs
    since the expendables can concentrate on getting the payload up there
    and doesn't have to push life support systems and people into orbit...
    
    	Out of curiousity, does anyone know what percentage of the
    shuttle's launch-ready weight is made up of the crew, life support
    systems and backups-to-backups that wouldn't be on an ELV?
    (Preferably, these numbers would not include the weight of the fuel
    so that judgements on the percent of fuel wasted on the people can be
    figured out...)

      I think the shuttle launches about 50,000lbs. An ELV built out
    of shuttle parts could launch about 3 times that amount.
    
      I agree that ELV's are a way to go. My point about the shuttle
    is that running a fleet of 4 prototypes is the worst of 3 choices.
    You pay all the overhead of maintaining the technology with out
    any economy of scale.
    
      Two better choices would be to put the shuttle into production
    and build a larger fleet or scrap the program and build ELV's. I
    like the first choice because I think the shuttle is a versital
    system. There are other things to consider besides price/lb.
    
      George

    
    	I still disagree with the bottom line.  Yes, running a fleet
    of 4 prototypes *is* very expensive, but there are two ways of looking
    at the economics of launch vehicles:
    
    	1)  Building more will result in a lowered price per shuttle.
    Lowered average price is good, therefor build more shuttles.
    
    		-or-
    
    	2)  While building more will result in a lowered price per shuttle,
    the incremental price (even with the lowered average) of having
    one ton more of launch capacity is *still* higher than with ELVs.
    
    	Going back to the obviously silly notion of using a Ferrari
    to go food shopping:  Having many Ferrari's is less expensive per
    vehicle than having one since spare parts could be bought in quantity.
    (Lets assume that Ferrari has a bulk discount rate for units of,
    say, 10. :-)  A couple of pick-up trucks, though, will *still* move
    the groceries a lot cheaper.  You might definitely need a few Ferrari's
    for emergency high-speed runs across the country for your favorite
    Pizza, but the total cost of your vehicles' transport capacity is lower
    with having mostly pick-up trucks.
    

      I think the Shuttle is more like the DC-2 than the Ferrari. The
    DC-2 and the following DC-3 was a big success because it could
    go just about anywhere and do just about anything in all kinds
    of weather. It could carry people, cargo, or an army platoon. It
    could work a scheduled flight or act as a gunship, etc, etc, etc.
    
      If you knew that you wanted to move 20 army men and a jeep from
    St Louis to Boston in a vechical that you were going to use once
    and throw away, you could probably have designed something
    better than a DC-2, but it was very versital.
    
      However, if there had been only 4 DC-2s all owned by the U.S.
    Government and if they only built a new one after a crash, the
    DC-2 / DC-3 would never have been a success. The Berlin Air Lift
    would have been a failure and PBA wouldn't be flying people to
    the Cape.
    
      The Shuttle is capable of doing a lot of things that can't be
    done with ELV's. Running a fleet of production shuttles would
    also provide a steping stone to more advanced shuttles just as
    the DC-2 lead to the DC-3, DC-4, DC-6, DC-7, etc.
    
      George

    
    	By this line of reasoning, however, since nothing is
    technologically stable, everything could be called a DC-2.
    Following this further, it would mean that everything that pushes
    technology *must* be made in mass production or else it is dooming
    successive technology to die.
    
    	I think a good counterexample is the original CRAY-1.  It pushed
    technology, *very* few were made -- nothing approaching mass
    quantities -- but yet it made a good basis for the -1S version
    and the rest of Seymore's saga is history.  In short, deciding that
    something can't push technology and be used as a stepping-stone
    to something better because few were made is not something I would
    agree to.
    
    	The CRAY-1 makes for a good example due to its pricetag.  Unlike
    the DC-2, shuttles aren't exactly cheap items nor will they be even
    with a lowered cost average of producing ten more of them.  Even
    today, with the greater production of CRAYs lowering the price,
    they are still a tad bit higher than I can get my boss to sign off
    on! :-)
    
    >   The Shuttle is capable of doing a lot of things that can't be
    > done with ELV's.
    
    	Yes, most definitely, there are things that the shuttle can
    do that ELVs can't do.  My point in my original reply was that since
    this difference in functionality *does* exist, use the best vehicle
    for the mission.  If the shuttle is needed, use it.  If not, use
    an ELV.  Whatever does the job with the least expense is the
    appropriate tool to use.
    
    >                  Running a fleet of production shuttles would
    > also provide a steping stone to more advanced shuttles just as
    > the DC-2 lead to the DC-3, DC-4, DC-6, DC-7, etc.
    
    	Running a production line of expensive items when there are
    clear budget restraints does not encourage the development of better
    items.  Rather, it encourages the implementation of the research
    to be put off since the politicians are going to cry "What?  You
    want *how* much for new shuttles?  What is wrong with the 10 (at
    $xB each) we have/are building?"  You can argue that the politicians
    are under-funding NASA (an argument that I would agree with you
    on), but there are budget constraints that make building 10 impossible
    to do at the same time of planning a space station and proposing
    a new type of shuttles to be build en masse.
    

    It would almost seem that the preceding discussions imply that the
    shuttle program has a cross-over threshold. Further, the program would
    seem to be on the "short" side of the threshold today. 
    
    The shuttle program should build 10 - 15 ships (and yes this might use
    up all of NASA's budget). However, the program would get over this
    threshold and experience a new economy of scale. 
    
    Each time a new technology is pressed into the public eye, PROVING that
    the technology is really worth it (the investment of money and
    regrettably lives), does not come until the technology is in "common
    use". In the case of a space program or the computer example sighted
    earlier, someone had the foresight to bring forth a new means of flying
    in space or computing faster. If the CRAY-1S was not built and
    marketed, would the CRAY still be acceptable in the public eye? (If the
    CRAY-1S was not built, the public would still be questioning its worth
    today.) 
    
    For the shuttle to succeed, it must come into common use (private,
    commercial and, yes, military). For it to reach that point enough
    ships must be available, and flying, to demonstrate common use. 

    Carl Leeber

  Have you ever notice that once in a while you hear about a plan that just
doesn't sound like it is going to work? I think we have one in the works at
NASA and that is what got me started on all of this. 

  NASA just announced that they are going to plan to extend the average time at
the space station from 3 months to 4 because they think they will only be able
to support 3 shuttle maintenance flights per year to the station instead of the
4 originally planed. 

  If things go the way they have in the past, this really means that they will
be lucky to fly 2 maintenance flights a year and they may not be evenly spread.
This suggests that people in the space station should be ready to stay up for
periods of 6 to 9 months. (Notice that even the Soviets switched to people last
month on short notice. NASA may or may not have been able to do that). 

  Now what happens if/when another shuttle is lost? With only 1 or 2 flyable
shuttles left (there is usually one in the shop for overhaul), they may not be
able to support the station at all until a replacement comes along. Under the
most optimistic scenario, the people on board return in the escape system,
station operations are suspended, some small station contractors go out of
business, some large station contractors leave the station business, and a few
years later the station support has to go through a startup procedure. 

  In a pessimistic scenario, the station runs out of fuel, the orbit decays,
and the station re-enters the atmosphere (it's happened before).

  A fleet of 10 shuttles with 2 or 3 launch sights would solve this problem.
I agree it is expensive but I don't see the space station working without a
larger fleet of shuttles. 

  Also, with a larger fleet of shuttles, they wouldn't have to all fly at
once so some of the SRB's could be used with External tanks as unmanned
HLVs. All that you would need extra would be an expendable cargo bay and an
engine pod that could be retrieved by a later shuttle flight.

  It would then make sense to get a second source for the External tanks
which could reduce their cost.

  George

    Maybe we lease the European shuttle for crew change and resupply?
    It's supposed to be smaller, and with lessons learned from our
    program it might be cheaper to produce?
    
    Mike H.

    
    	(Sorry that I couldn't continue the discussion yesterday, but
    the headache that I mentioned in .14 turned into a full-blown 24
    hour flu...)
    
    	I think that there are two separate issues dealing with the
    space station -- resupply and changing crews.  The same type of
    vehicle is *not* needed for both of these missions.  Resupply missions
    to the Russian space station are not done by a manned crew, but rather
    by an ELV.  Is it because they lack in the human-lift capacity?
    No, on the contrary, they have demonstrated the ability to launch
    many missions.  Why do they use an ELV, then?  Its cheaper and gets
    the job done.
    
    	Changing crews, though, tends not to be all that practical by
    an ELV. :-)  Use the shuttle for this, and get enough shuttles to
    do *this function* properly.  (6 total, perhaps?)  All I'm saying,
    though, is not to use the expensive shuttles to play the role of
    a Mack truck.
    
    

      I agree, an ELV built out of shuttle parts could take lots
    of stuff up there cheap.
    
      The problem is that I don't see the 4 shuttle fleet making more
    than 2 crew switch flights a year (their estimate of 3 - the usual
    1). The Soviets can launch a maned ELV when it is needed.
    
      If/when another shuttle is lost, even if the others keep flying,
    that number would go from 2/year to 1 or less/year.
    
      I don't believe that we can support a maned station with that
    little a crew switch capability.
    
      George

    The preceeding discussions have not really touched upon a couple
    of limiting factors with the shuttle as it exists today, safety
    and reliability.
    
    The shuttle is too complex and pushes technology too far to be a
    reliable vehicle. The Titan 4 should prove to be a more reliable
    vehicle as it is based upon the technology of over 20 years of Titan 3
    flights. The Titan 3 familay has a very good reliability record, 
    recent failures not withstanding. It has almost the same payload
    capability as the shuttle (more when using the Centaur G Prime upper
    stage).
    
    The shuttle is also inherently unsafe as a manned vehicle. If nothing
    else, this should dictate that it only be used when humans are required
    on the flight.
    
    Earlier replies made a similar point on an economic basis, as man-rated
    vehicles will be more expensive.
    
    With the benefit of 20-20 hindsight, NASA would have been in a better
    position if they had built a heavy lift system that could launch
    the orbiter or other payloads (like the Soviet Energia booster)
    but it probably would have never been approved.
    
    With regard to the Soviet ELVs, I suspect that they are far cheaper per
    launch than comparable US vehicles. Their launch prices reflect this
    even after you allow for hefty government subsidies. They achieve this
    through volume. They have used their A series launchers from Sputnik 1
    through to this day, with evolutionary changes over time. It has
    apparently flown single stage (stage and a half, to be accurate) and
    with three different upper stages to date, making 4 variations in 30
    years. By comparison, the US' most prolific launch vehicle, the Delta,
    has had over 40 variations. I have somewhere on file a photo of a
    production line for the A series. There seems to be 30 or more first
    stages being assembled. The Soviets have adopted Henry Ford's
    philosophy of mass production, 'you can have any color you like as long
    as it is black'. The A series launcher is the only launcher the Soviets
    have used for manned flights, BTW, compared to 6 (nearly 7) in the US
    program.
    
    They also adopt a 'keep it simple, stupid' approach to a lot of
    their satellite designs, requiring more launches per year which
    also helps keep the cost per launch down. The US DoD in particular
    likes to cram more and more function and complexity on each new
    satellite which tends to push launch prices up.
    
    gary 

      I think that if anything the shuttle has shown itself to be very
    reliable. How many U.S. Launch vechicals or even U.S. prototype
    aircraft only had one accident in there 1st 25 flights? Also, I
    think the Rogrers commission showed that the problems that caused
    the accident were political not technical.
    
      Now that it has been debugged, I think the shuttle will be a
    very safe system. I would rather fly the shuttle than a DC-10.
    
      George

    	I think the point that was being made was that the reliability
    of the Soviet launch vehicles was acheived without alot of todo
    during each launch.  Sure the shuttle has shown itself to be reliable
    with only 1 failure in 25 flights (actually there have been other
    failures of the boosters of exactly the same type as resulted in
    the last failure, they just didn't result in a failure of the whole
    system) but that's not the point.  The point is that each time you
    launch the shuttle NASA has to jump thru all kinds of hoops to get
    the thing off the ground.  I remember hearing in the news after
    the accident about how the prep & launch crews were working all kinds of
    overtime to get the shuttle flights off the ground.  This with just
    4 shuttles!  What kind of manpower would be needed to prep and launch
    a fleet of 10 or 20 shuttles on a regular basis?  
    	The STS is a very complex system,  an ELV based system is alot
    less complex.  It makes sense to have the 2 systems in use at the
    same time.  The thing you HAVE to remember is that the largest problem
    NASA has among thier many problems is thier budget.  They simply
    can't get the funding necessary to support a large fleet of shuttles.
    Not in today's world.  It's nice to be able to speculate about what
    would be possible with an unlimited budget, but you have to realize
    that you're living in a dream world when you do so.  Face it guys,
    while everyone in the US likes to see us on the "cutting edge" the
    benefits of the shuttle simply have not impacted the average citizen
    that much (I can hear the howls now :-)).  The main impact of the
    space program on the average citizen has been through the launching
    of weather and communications satellites and these can be launch
    a hell of alot cheaper with ELV's.  In my opinion, the public wants
    NASA to keep moving foward, but not at the cost of many other programs
    that the government runs at the same time.
    
    Rich

      As I remember from the Apollo days, launching maned ELV's was
    just as complicated as launching the shuttle.
    
      My point is that if we are going to have a space station we
    have to be able to launch people. There are no current plans for
    maned ELVs. The space plane is decades away and I think it will
    be just as complicated to launch as the shuttle. Only 4 shuttles
    will not support the space station. If we try to build more shuttles,
    the price per shuttle should come down and we may be able to do
    it within the budjet.
    
      Once the space station gets going, private money for launch support
    should become available from the private sector for manufacturing
    in zero G.
    
      Sure, the plan has problems, but I don't see any alternative if
    we want a space station.
    
      George

    re .22
    
    Agreed. A good example is the turnaround time after the two Soyuz
    launch failures and the assurances given to NASA before ASTP mission.
    My estimate is that they can have an A series launcher ready in
    about 48 hours.
    
    re .21
    
    Ah, but the shuttle was declared operational after the fourth flight
    (sarcastic :-) and there have been quite a few near misses including
    a couple of SRB nozzle erosion problems that were a few seconds
    away from catastrophic failure and incorrect SSME shutdowns.
    
    I don't know the current figures, but a couple of years ago the
    Delta family had had 100 consecutive successful launches. This is
    approaching what a 'space truck' should have.
    
    The other factor to consider is failure mode. All previous manned
    US missions have had failure contingencies built in, e.g. escape
    towers, ejection seats, engines that could seperate the capsule
    from the booster in the event of an abort outside the atmosphere.
    The shuttle has no form of 'graceful degradation' in the event of
    any failure in the first two minutes and has little that can be
    relied upon until it reaches the 2 engine abort to orbit stage.
    Space technology is simply not anywhere near the point where we
    can build a vehicle that is so reliable that we don't need contingency
    systems.
    
    One way to approach this goal is to use simple proven systems, the
    antithesis of the shuttle design.
    
    I would also rather fly on the shuttle than a DC-10, but for reasons
    unrelated to safety.
    
    gary

    re .23
    
    The Saturns were also pushing technology and were not designed for
    routine use.
    
    I doubt that it took days to launch, say, a Titan II ICBM, or even
    an Atlas.
    
    It will be interesting to see if the Soviets, after they have their
    shuttle operational, retain the Soyuz or whatever follows it. I
    think they will. If they ever fly a manned spaceplane as the DoD
    has been predicting for the last couple of years, I think it will
    be the Soyuz replacement, not the shuttle.
    
    gary

    
    Re: .23
    
    >  As I remember from the Apollo days, launching maned ELV's was
    >just as complicated as launching the shuttle.
    
    	Yes, launching the Apollo was complicated and expensive and
    it was an ELV.  As pointed out in an earlier reply, any time a human being
    is on board, the expense and complexity of the launch vehicle goes way
    up, (npi).  I believe that the definition of "ELV" being used in
    this discussion, though, is now an "unmanned space truck" type of
    vehicle.
    
    >                                                 Only 4 shuttles
    >will not support the space station. If we try to build more shuttles,
    >the price per shuttle should come down and we may be able to do
    >it within the budjet.
    
    	Why is 4 shuttles not enough?  If supplies are lifted on (cheap)
    ELVs, the shuttle flights can be reserved for crew changes.  If
    each shuttle can fly only once every four months, a monthly crew
    change can still be made if you wanted to rotate them that often.
    In addition, heavy-lift ELVs could build the space station in fewer
    launches than could the shuttle.
    
    							-craig
    
    p.s.  Incidently, given the Soviet's ability to launch simple systems,
    including manned systems, should we contract with the Soviets that
    they'll launch up a craft to rescue our space station astronauts
    if something goes wrong at the station?  If I were on the station,
    I'd certainly hate to wait for NASA to prep and launch something...

    I submit that a lot of the complexity involved in launching the
    shuttle is not because there are people on board (i.e. safety issues),
    but because of the extreme flexibility of people on board.
    
    Sure, the countdown takes a couple days, but how much of that is
    related to people?  Sure the stacking takes a few days, but how
    much of that is related to people?
    
    The real time that is involved in launching a shuttle is not measured
    in days, but in months.  This is the time spent figuring out manifests,
    crew schedules, electrical interface compatibility (between cargo
    and shuttle) etc etc.  AWST said recently that "the new shuttle
    program" will now allow configuration changes any closer than 
    n months from launch where n is on the order of 6.  I submit that
    most of this is because the shuttle has
    
    	1.  The flexibility of a crew which needs scheduling
    
    	2.  The flexibility of being able to do multiple missions on
    	    a single flight (read multiple experiments, multiple cargos,
    	    etc)

    
    We all know about software that has so many options that you can't
    figure out how to run it.  That, to me is the shuttle's problem.
    ELVs can offer much faster turnaround because they don't do much
    except drive the payload up there and let it go!  At most, and ELV
    may have 3 or 4 payloads.  That is a lot fewer permutations than
    3 satellites, 10 GetawaySpecials, a middeck experiment or 2 and
    ...
    
    Burns
    

    re .26   rescue
    
    One of the outcomes of ASTP was the androgynous docking adaptor
    which was proposed to be used on future US and Soviet missions to
    facilitate rescue, amongst other things. The Soviets seemed to be
    pushing it more but I'm not sure who dropped it first. The docking
    mechanism between Mir/Kvant looks vaguely like the ADA although
    it is hard to tell from the photos.
    
    re .27  complexity
    
    Interesting thought, but I am convinced that a significant part
    of it is complexity for complexities' sake. The mission profiles
    for the shuttle are so complex partly because they made the vehicle
    so complex to start with. Trying to build a $10 spaceship on a $2
    budget contributes to complexity as well.
    
    gary

    
    Re: .27
    
    	How much good publicity would NASA get if they only used the
    shuttle to go up and kick a couple of satellites overboard?  They
    *have* to make complex flight plans to justify the use of the shuttle
    and the inclusion of people.
    
    	Which came first -- the complexity or the shuttle? :-)

      A few notes back someone suggested that the shuttle would only
    be used for crew changes. Not so. It will be needed to launch
    TDRS, The KH-12 spy satellite, the space telescope, space lab,
    SDI tests, that European unmaned platform that is deployed and
    retrieved later, and several other programs. That is why NASA
    lowered their estimate for crew changes from 4/year to 3/year
    (I claim that means 2/year).
    
      I'm not sure much of an escape system is needed. The major
    shuttle bugs have been fixed. As the shuttle matures the 4%
    failure rate should improve. The airlines don't provide an
    escape system even though they still have accidents. Test piolots
    have dealt with much worst than 4%.
    
      I would still like to know what the alternative to the shuttle
    is? In summary:
    
      NASA says only 3 station crew changes a year (most likely 2).
      If another shuttle is lost that will go down.
      There are no maned ELVs planed.
      The space plane is decades away and will be more complicated
        than the shuttle.
      Hermes on Titans would be just as complicated with less crew
        capacity.
    
      What other way can the U.S. go forward with a maned space program
    than to build a fleet of shuttles?
    
      George

    
    Re: .30
    
    	What other ways?  I believe the last dozen or so replies have
    given ample suggestions... :-)
    
    >  A few notes back someone suggested that the shuttle would only
    >be used for crew changes. Not so. It will be needed to launch
    >TDRS, the KH-12 spy satellite, the space telescope, space lab,
    >SDI tests, that European unmaned platform that is deployed and
    >retrieved later, and several other programs. ...
    
    	Please be careful of your use of the word "needed".  No, the
    shuttle is not "needed" for any of those functions you listed except
    for space lab (since that infers having people around) and the
    retrieval of the European platform.  There is a major difference
    between what is currently planned for it (which you listed) and
    those functions for which it is needed - i.e. those where no ELV could
    possibly do the job.
    
    > I would still like to know what the alternative to the shuttle
    >is? In summary: ...
    
    	I don't recall anyone saying to get rid of the shuttle.  What many
    (including myself) have said is to use the shuttle when it is
    absolutely needed and use ELVs elsewhere.  We have said that 15-20
    shuttles are too many, not that none should exist!
    

    Easy. For payloads that do not require the presence of humans, the
    alternative is the Titan-4 system, previously known as the
    Complementary Expendable Launch Vehicle. NASA tried to squash the
    CELV program but the DoD won, otherwise the US would be even further
    behind in acquiring launch capability.
    
    The KH-12 can be launched on Titan 4. I don't know what its mass
    and usual upper stage are but the Titan 4/Centaur G-Prime can launch
    all planned DoD payloads. TDRSS can go up on Titan/IUS (in fact,
    I think one has or at least they tried and it failed). SDI tests
    are better served by smaller expendables in many cases - the
    environment around the Shuttle is not too good for some of their
    technology tests. It is politically more expedient to quietly launch
    the odd Delta than have it piggy back a ride with other payloads.
    
    The DoD has just applied for budget for 27 more Titan-4's. They
    don't want to rely upon Shuttle any more than they have to. The
    Titan-4 was specifically designed as an alternative to Shuttle and
    can carry all of the payloads that Shuttle could have with the
    Centaur G upper stage. With the cancellation of Shuttle/Centaur there
    are some Titan payloads that will be too heavy for the Shuttle.
    
    The Spacelab is obviously man oriented so any suggestion of not
    launching it on the Shuttle is dubious. It may be that some of its
    intended experiments don't really need a crew (a guess on my part).
    I think the Space Telescope was designed to be man tended so it
    may have to go up on Shuttle.
    
    In my opinion, the NASA planetary flights that were to use
    Shuttle/Centaur should be flown on Titan-4 as well but NASA is
    violently opposed to that, preferring the convoluted sling shot
    flights to compensate for the lack of a high energy upper stage
    for the Shuttle. The Titan-4 would need some work, most likely a
    smallish solid upper stage, probably spin stabilised (PAM-D2 maybe
    or the never flown PAM-A). The planetary flights were to use Centaur
    G Prime but Titan-4/Centaur G Prime has about the same payload capacity
    as the Shuttle/Centaur G.
    
    Test pilots HAVE dealt with much worse than a 4% failure rate. Its
    their job and they don't carry paying customers along for the ride.
    
    The bottom line is that you don't need humans along for the ride
    for many of missions planned/talked about for the near term future.
    While NASA should work towards a reliable (first), cheap (far distant
    second) manned spacefilght capability, using random satellite and
    space probe launches as an excuse to cart a crew along is dumb.
    
    gary

      There have been good suggestions for launching stuff but no one
    has disaggreed with my statement that NASAs best guess is a max
    of 3 station crew changes a year. No one has disagreed that 2 is
    more likely given their guess of 3 and no one has disagreed that
    that number would go down if another orbiter was lost.
    
      There are no plans to create any other system that could support
    the space telescope. Even if an ELV could launch it, only the
    shuttle could bring it back for servicing. The Airforce KH-12 can
    only be launched on the shuttle. I think it is a configuration
    rather than a size problem. SDIO will probably need shuttle support.
    
      My appology if I missed it but I don't recall seeing other
    suggestions for maned flight. I believe that maned flight is important
    for us to get back to a leadership position in space.
    
      Here is my list of programs that I believe need the shuttle.
    
      Space station crew change.
      Space lab.
      Space Telescope support.
      European pallet.
      Airforce KH-12.
      SDI.
      Satellite recovery and repair.
      Return of manufactured goods to Earth.
      Lunar base support.
      Mars and beyond.
    
      I don't see any way that we can be a leader in space without these
    programs and I don't see any way that 4 shuttles with a 4% loss
    rate can support these programs. ELV's will launch the parts but
    they won't put them togther. Robots that work at the maned inteligence
    level are a long way off.
    
      George

    I apologize if I missed this when I went thru the last batch of
    replies.  I'm not as concerned over the number of shuttles as much
    as what comes next.  Okay, we have an "operational vehicle" (more
    of a working test bed).  Where's the next generation?  I don't see
    the follow-up that improves and builds upon the current design.
    It took a disaster to coerce NASA and Thiokol to make needed
    improvements on the SRBs.  If you use the airplane as a comparison,
    it's like we built the first jetliner and said "Tah dah!  Ok, let's
    go find something else to do."
    
    We went from the V2 to Jupiter to Redstone to...Saturn and then
    stopped.  Instead of getting the most mileage out of current designs
    and building upon existing vehicles, we seem to be more interested
    in throwing things away and breaking new technological ground. 
    We need to do the latter but not at the expense of the former.
    
    					Mike

    
    Re: .33
    
    	Ok, I'll bite.  You requested disagreements, and I'll be willing
    to supply one! :-)
    
    (paragraph that nasa says 3 crew changes per year and a better guess
    is 2)
    
    	If the shuttle is reserved for manned-required activities
    (including crew changes) rather than tossing satellites overboard, I
    believe that more than 3 crew changes can be done each year using the
    current shuttle fleet.  NASA's prediction of 3 (with your counter
    of 2) is, though, reasonable if the shuttle is expected to continue
    to do everything.
    
    >  There are no plans to create any other system that could support
    >the space telescope. Even if an ELV could launch it, only the
    >shuttle could bring it back for servicing.
    
    	Yes, so why not use an ELV to launch it and use the shuttle
    to retrieve it?  All along, I've been saying to use the shuttle
    for what it is good for - retrieving satellites as a perfect example.
    
    > The Airforce KH-12 can only be launched on the shuttle.
    
    	If so, then yes, we have another situation where the shuttle
    is required since other launch vehicles can not do the job.
    
    	Bottom line: There are some things that the shuttle's capabilities
    are required for - and you have demonstrated some of these - but
    that does *not* provide a rationale for using the shuttle for
    everything!  For payloads that don't require the shuttle, the most
    cost-effective vehicle should be used.
    
    >  My apology if I missed it but I don't recall seeing other
    >suggestions for maned flight. I believe that maned flight is important
    >for us to get back to a leadership position in space.
    
    	You need not apologize, for you did not miss anything.  (Or
    else we *both* missed it! :-)  Noone (in this particular discussion,
    that is) has suggested that manned flight is improper and should
    not be done.  What we have said is that manned flight is inherently
    expensive and so should be reserved for things that absolutely need
    a person along.
    
    
    	As to your list of shuttle needs, I would agree that all of
    them need use of the shuttle except for: ("servicing" = in-orbit
    repair/refueling or returning to earth)
    
    	Space Telescope -- servicing, yes.  Launching, no.
    	European pallet -- servicing, yes.  Launching, depends on size.
    	Airforce KH-12  --     "       "       "          "     "  "
    	SDI -- Highly improbable, perhaps better done on an ELV due to
    		secrecy.
    	Satellite recovery -- yes, yes, yes.
    	return of manufactured goods -- yes, yes, yes.
    	lunar base support -- yes for moving people, No for just hauling
    		supplies around.
    	Mars and beyond. -- ditto the lunar base support.
    
    

    RE: 32 and 35
    
      I didn't see 32 before I wrote 33 for some reason so if you say
    the KH-12 can fly on a Titan 4 then I'll scratch it from my list.
    
      Even the modified list in 35 is a lot for the current fleet of
    shuttles and may be impossible if a shuttle is lost. The biggest
    problem is that it does not allow for growth.
    
      I agree 100% that if people don't have to be there an unmaned
    launcher is the way to go for science, military, and comercial
    applications. My argument is that the shuttle fleet is not large
    enough for the maned flights planed even if it is limited to the
    list in .35, and there is no hope that it will allow for new maned
    programs.
    
      Also, with a larger shuttle fleet, if NASA developed a recoverable
    engine pod that fit under the shuttle main tank, they could use
    shuttle hardware to launch cargo. During times when more people
    were required, the shuttle hardware would launch shuttles. During
    times when more cargo were required, the shuttle hardware (with
    no shuttle or people) would launch cargo. We would be getting two
    types of launch systems for the price of one.
    
      The unmaned shuttle derived system would be better than an ELV
    because we would recover all of the expensive hardware. The SRB's
    return as normal, and several engine pods could be returned with
    one shuttle flight. It might not be that hard to make the engine
    pod a lifting body, cover it with tiles, and have it fly back itself.
    
      George
   

    In response to the list of missions for the shuttle a couple of
    replies back.  It listed recovery of manufactured goods as a possible
    mission that could only be performed by the shuttle.  Not true.
     The Air Force has long used recon satellites which have returned
    film canisters by parachute to Earth.  These "capsules" are retrieved
    by plane while they are decending by parachute.  A similar method
    could be used by a space station crew to return materials manufactured
    in space thus eliminating the need to a shuttle launch or at least
    reducing it's tasks to be performed.
    
    Rich

     A lot of the "capsules" that are used to recover things pull high
    g loads during reentry. Their capacity is not as large as the shuttle
    and recovering them by grabing them from the air or sea has to be
    expensive.
    
     I am sure that some goods that need zero G for manufacture shouldn't
    be exposed to high G loads during reentry but that could be wrong.
    Low G's on launch are also a shuttle benifit for some things but
    an unmaned shuttle derived HLV would also perform like the shuttle.
    
     From this weeks AW&ST I get the impression that the shuttle managers
    have no idea where they are going or why. The artical said that
    they were cutting back on commercial flights but as the military
    pulls away from the shuttle there may actually be a shortage of
    payloads. It said that many high level NASA managers want to limit
    the shuttle to flying people up and down.
    
     This will get worst before it gets better. It doesn't make sense
    to run 4 shuttles. I still think they should either build a fleet
    or can the shuttle altogether.
    
     The last great Shuttle / Red Sox fan,
     George

Article: 15273
Newsgroups: sci.space.shuttle
From: [email protected] (David Cornutt)
Subject: Pathfinder (was: HOW MANY ARE THERE?)
Organization: NASA/MSFC
Date: Tue, 28 Sep 1993 21:08:35 GMT
 
[email protected] (Len Struttmann) writes:
 
[quoting someone else; the attributions have gotten fouled up]
>|> 	A rough model with the same size parameters and weight
>|> distribution was built to do vibration tests at the Marshal
>|> Spaceflight Center in Huntsville, AL. 
 
As originally built, Pathfinder was ballasted to actually be about
the same weight as Columbia, around 188,000 lbs.  It was the same
size and weight, and it had working landing gear and some other
things.  But visually it didn't look a whole lot like an orbiter.
 
It was not itself used for vibration tests; rather, it was used
as a fit check model for various things at MSFC, in preparation
to Enterprise's being sent here for vibration and other dynamic
tests.  It was used to test the portable mate/demate setup that
MSFC came up with to unload Enterprise at the Redstone Arsenal
airstrip.  Then, it was actually towed down the road to the
test area to check for clearance to power lines, street signs,
etc.  Finally, it was used to test the lifts and cranes at the
dynamic test stand, which had been modified to accomodate a
full Shuttle stack including Enterprise, an ET, and an SRB pair.
(It was originally built to do dynamic tests on the Saturn V.)
 
After this, it went to KSC for a while.  They used it to practice
orbiter lifting and stacking in the VAB, pad rollouts, and pad
operations.  They also used it for practicing postlanding ops.
(For this purpose, I think they installed a rudimentary comm
system and had crew surrogates on board.)
 
It has since been
>|> "prettied-up" to look like a real orbiter, and has been
>|> displayed at several sites, including Japan.
 
Around 1983, a Japanese group paid Teledyne Brown Engineering
a few million dollars to fix it up to look like an orbiter.
(In the process, I think they removed most of the ballast, so
it probably doesn't have the same weight or CG as a real orbiter
any more.)  It did a tour of Japan for several years, then went
some other places.  I think it was at the Paris Air Show one
year.  It came back to MSFC in 1988.
 
>This last one's name is Pathfinder and is now on display at the U.S. 
>Space and Rocket Center in Huntsville.  It's a great display.  It's got
>a real ET and full size mackup SRBs attached and is mounted at an angle
>such that you can walk beneath the entire assembly.  Very impressive.
 
Indeed it is.  The ASRC put it on display in 1989.  BTW, the ET is
one that was used for years at Stennis for SSME testing; it is also
the one that was used for the Enterprise dynamic tests.  And, the
SRBs are not mockups.  They are test articles that were built by
Thiokol.  The casings are jointless and are made of filament-wound
carbon fiber; they were used as structural test articles.  (I don't
know for sure if they were every actually fired.)  For whatever
reason, they didn't work, and Thiokol donated them to the ASRC in
1990.  Their natural color is green; they've been painted white to
look like the flight articles.  
 
Also, the SSMEs on Pathfinder are real.  Two of them are retired
engines that flew several flights on Columbia.  The third was a
ground test article.  (I don't remember which is which.)
 
>It's on display in Shuttle Park, the area between the Main (Museum)
>building and the Space Camp Habitats.  I just got back from Space Camp,
>so this info is fairly up-to-date.
 
Hope you enjoyed the trip!
-- 
David Cornutt, New Technology Inc., Huntsville, AL  (205) 461-4517
([email protected]; some insane route applies)
"The opinions expressed herein are not necessarily those of my employer,
not necessarily mine, and probably not necessary."

Article: 15272
Newsgroups: sci.space.shuttle
From: [email protected] (David Cornutt)
Subject: Re: HOW MANY ARE THERE?
Organization: NASA/MSFC
Date: Tue, 28 Sep 1993 20:43:28 GMT
 
[email protected] (Anthony Parker) writes:
 
>	I'm a University Student here in Australia and was wondering if you
>could tell me how many space shuttles exist?
 
I thought I'd go ahead and post just so I can give the full rundown.
I'm probably making a mistake, since I'm sure a dozen others will
do the same, but...
 
The orbiters currently flying are:
 
OV-102 Columbia --- next flight is Octber 14 (STS-58), with any luck
OV-103 Discovery -- next flight is around January 20 (STS-60)
OV-105 Endeavour -- next flight is December 2 (STS-61)
OV-104 Atlantis --- currently at Rockwell's plant in California for
                    refurbrishment; scheduled to fly again in late 1994.
 
The other orbiters that have been built are:
 
OV-099 Challenger - originally built as an airframe structural test
                    article, and then converted to a full-fleged orbiter.
                    As everyone knows, it was destroyed in the STS-51L
                    accident on January 28, 1986.

OV-101 Enterprise - used for landing tests from 1979-81, and then for
                    other test purposes until 1984.  Enterprise was
                    never outfitted for space flight.  It is now in
                    storage at Dulles Airport in Washington, as was
                    convered in a recent thread in this newsgroup.

OV-098 [no name] -- Another structural test article.  This was not
                    a full-fledged orbiter; it was just the aft part 
                    of the airframe, complete with most of the aft-
                    compartment equipment, plumbing, and electricals
                    (APUs, hydraulics, propellant fill-and-drain, etc.)
                    It was used at Stennis Space Center to test
                    SSMEs and to test the reaction of the airframe to
                    flight thrust loads.  It was dismantled and sent
                    to MSFC in 1988, where it was last used to build
                    a full-scale mockup of the proposed Shuttle-C
                    (which was canned by Congress in 1991).  I believe
                    it is now in storage in building 4710 at MSFC.
-- 
David Cornutt, New Technology Inc., Huntsville, AL  (205) 461-4517
([email protected]; some insane route applies)
"The opinions expressed herein are not necessarily those of my employer,
not necessarily mine, and probably not necessary."

Article: 15276
From: [email protected] (Brian Stuart Thorn)
Newsgroups: sci.space.shuttle
Subject: Re: HOW MANY ARE THERE?
Date: Tue, 28 Sep 93 17:17:08 PDT
Organization: The Portal System (TM)
 
>What was the "full scale" model of the shuttle at the KSC in the display
>area used for??? I don't remember its name...
 
 "Ambassador"
 
-Brian

Article: 18283
From: [email protected] (Bill Walker)
Newsgroups: sci.space.shuttle
Subject: Pathfinder Display
Date: 14 Mar 94 11:33:43 -0600
Organization: Arnold Engineering Development Center
 
Some time earlier, someone posted to this group asking about the
Pathfinder shuttle display at the U.S. Space & Rocket Center in
Huntsville, Alabama. I just returned from a fact-finding trip down
there, and here's what I found about Pathfinder: 
 
The Pathfinder orbiter is a non-functioning mockup that was used for
checking out the orbiter-handling facilities at Marshall (and perhaps
elsewhere). Its structure is at least partially wood, according to a
photograph of the unfinished article suspended from a handling crane. 
The engines seem to be real -- I could find no documentation on them. 
It would make sense that they are engines removed from active shuttles
because of component failure or some other reason.  It has no landing
gear doors, it has no tiles, and I don't think the cargo bay doors
open (not sure on this). 
 
The external tank is real.  Of course, it hasn't flown, but it was
used for years at Stennis for containing propellant used in the
testing of the engines.  As someone noted in an earlier post, the
insulation on the tank is soft, and items thrown at the tank stick in
the insulation.  You can seen thousands of little slots where people
have thrown coins into it. Maybe it's like a wishing well, and the
coins are collected and given to a charity.  :-) 
 
The SRB components were used in various ground tests.  They did not
fly. However, the nose cone of the north SRB (seen from the parking
lot and the road) is from the maiden flight of Columbia in 1981. 
Normally, the nose cones are not recovered, but this one landed in
such a way that it was floating and the recovery crew picked it up. 
So that there's no confusion, the nose cone is just the very end of
the SRB, not the section with the separation motors and parachute
(which IS recovered). 
 
Hope this helps.
 
Bill Walker ([email protected]) |
OAO Corporation                        |
Arnold Engineering Development Center  |  AEDC -- Home of the "Chicken Gun"
1103 Avenue B                          |
Arnold Air Force Base, TN  37389-1200  |

Article: 18342
From: [email protected] (TomKat)
Newsgroups: sci.space.shuttle
Subject: Pathfinder Display
Date: 17 Mar 1994 05:21:09 GMT
Organization: StarNet Communications, Inc
 
Umm...  I feel compelled to correct the earlier post...  as I have
studied Pathfinder in great detail at Huntsville S&R center.  Two
terms of Space Academy Level II (one college, one Adult) gave me a
respect of the displays there...  Not to mention, talking to Dr.
Conrad Dannenberg about the original design was a highlight I'm not
likely to forget for many long years. 
 
 Pathfinder (the obitor) is made of balsa wood...  made when one of
the "real" orbitors needed to make an emergency landing at White
Sands, NM (Northrup Air Base).  It's original purpose was nothing more
than making sure that the roads between Northrup and the airport were
wide enough for the "real" orbitor to make the journey unaffected. 
When that was done certain other curiousities were asked of it...  but
not much.  However, because of the seriousness of the situation (the
emergency landing), Pathfinder was commissioned into the orbitor fleet
(making it the second orbitor never intended to go to space (see
Enterprise OV-100 FFI)).

  Pathfinder was never decommsioned because of the Challenger
incident, or so it's rummored. 

 The SSMEs (Space Shuttle Main Engines) on Pathfinder are real... 
all three have been on several missions.  (the plaque you sought was
closest to the "Habitats" on the far end by the dedication marker. 
All three are still viable thought decommissioned because of age. 

 The ET is real.  Was one of the prototypes used for the "challenger"
class ETs (unpainted)  It never made a mission (big surprise there!) 

 The SRBs are real...  the Left one is an original model
(pre-challenger incident) that was decommissioned at the time of the
incident.  The right one is the "new" model with the tri-seal and is
(or so I understand) one of the ones used for testing the new design. 
 
 All of this information is availible at the six plaques surrounding
the Pathfinder and also I believe a documentuary has recently (1992)
been compleated about Pathfinder and should be availible at Huntsville
or Titsville, FL 
 
 Hope it helps.
 

From: we.anderson%[email protected] (Bill Anderson)
     
I showed TomKat's note to Amos Crisp, my former boss here at Marshall (he's 
now retired), and Amos just had to respond.  Here's what he said...



Mr. Tomkat.  Please do not use the information you put forward on 3/17/94 
about the Pathfinder Shuttle full scale display at the space and rocket 
center.  You are wrong in almost every detail.  Believe me, I was there and 
involved in the project which took several years to complete.  The orbiter is 
NOT balsa wood, it is mostly metal, and it was NEVER commissioned into the 
shuttle fleet.  It was a test article built originally at the Marshall Center 
in the mid-1970s to train ground crews who would later move the Orbiter 
Enterprise around the center, lift it off the carrier aircraft, and lift it 
into 400-foot tall test stand.  It is similar in shape and weight to the real 
orbiter.  At the time it was used at Marshall, though, it LOOKED NOTHING LIKE 
an orbiter.  It was just a metal framework.   After its use at Marshall the 
framework was transported to the Kennedy Center where it was used as a 
facility checkout and ground crew training device.  Later it was returned
to Marshall where it sat in a field for several months.   Then in the early 
1980's a Japanese consortium contacted us about rebuilding the Pathfinder to 
make it look like an orbiter.  The consortium planned to take the test 
article to Japan as a major attraction for "The Great Space Shuttle 
Exhibition."  We agreed to the plan on the condition that the article would 
be improved and returned to us after its use in Japan.  After it was 
returned, we helped arrange for its display at the Space and Rocket Center. 
The Pathfinder's SSME engine *bells* are real.  The ET was used at Stennis in 
all-up tests of the three-engine rear compartment of the orbiter.  After 
several uses, it was delivered to MSFC for use in the display.  The SRB
segments are the filament wound segments which were part of an experiment (not 
adopted) to replace the metal SRB's with the composite type.  The SRB aft 
skirt and forward nose cone sections are  metal and at least one of these 
parts, one of the nose cones, I believe, actually flew and was recovered from 
the ocean.  If a documentary is available which uses your information, it is a 
disservice to the shuttle program.  I can say this because I was involved in 
these activities.
     
Amos C. Crisp