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The Last 10 Days In The Space Shuttle's Bunker?, Atlantis apparently to be scrapped in 2008
dilo
post Feb 22 2006, 08:46 AM
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QUOTE (Bob Shaw @ Feb 21 2006, 11:32 PM) *
The 'spaceplane' concept came largely from German engineer Dr. Eugen Sänger who researched many rocketry technologies, such as regeneratively cooled liquid-fueled engines.

Perhaps slightly OT, I knew the Sanger project and I remember also a modern spaceplane project called "Sanger", in honor of this projectist. In the image I saw, it was a beautiful, very aveniristic model but I cannot find any info on that. Someone can help?


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edstrick
post Feb 22 2006, 08:57 AM
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We have to remember that the IDEA of a space shuttle is a good one. The one we got is a bad one.

Shuttle was supposed to 1.) provide access to and from space and serve as a work platform in orbit. 2.) Fly frequently. 3.) Fly Cheaply. 4.) Fly Safely.

It is about 80% successful at #1. Fails #'s 2 and 3 by 10x each, and Fails #4 by 100 to 10,000 or more times (depending on which early reliability claims you pick)

Why? 1.) We'd never built any reusable spacecraft or launch vehicles. Building shuttle right would have been like building a DC-3 Goonybird in 1925 instead of 1935.
2.) We had to enlist all possible customers to get the political support for the $ to build it, so it was designed to satisfy every one's hypothetical needs (especially the military's). The design was over-constrained by trying to please everybody.
3.) We tried to build it on the cheap.

Any of those 3 things inevitably would have compromised what we got compared with what we wanted. Together, they turned a great idea into a 35 year disaster.

From orbit insertion to atmosphere interface, the shuttle is wondererful. The rest of the time it's a disaster, like Dr. Jekyll and Mr. Hyde.
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Guest_PhilCo126_*
post Feb 22 2006, 09:45 AM
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After 25 years of Space Transportation System (STS) it looks like NASA is going to use ATLANTIS for spare parts wink.gif
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Guest_BruceMoomaw_*
post Feb 22 2006, 11:21 AM
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An excellent case can be made that the basic concept of the Shuttle was disastrously dumb-ass from the very beginning -- and Robert Truax made it in his January 1999 "Aerospace America" article, "The Future of Earth-to-Orbit Propulsion" ( http://www.teamprincipia.com/space/eto1.php ), which has been one of my Holy Tracts ever since I read it. Truax's most important point is that putting wings on a reusable LEO vehicle -- as opposed to a 2-stage vehicle in which the first stage parachutes into the ocean, and the second stage may or not be reusable -- is a breathtakingly idiotic notion from the start. Wings cut the vehicle's orbital payload by 2/3 (Griffin himself has memorably described the Shuttle as "a 100-ton shroud for a 30-ton payload"); they require absolute stability during reentry (whereas a capsule virtually stabilizes itself); they make a crash during the final landing vastly more likely; and they tremendously complicate any manned abort-and-escape (to the point of making it frequently impossible, as on the current Shuttle). They make sense on a vehicle that spends all its time moving horizontally through the atmosphere -- NOT on one that goes up through and then comes down through the atmosphere as fast as it reasonably can.

Actually, to quote his entire list of condemnations:

"Many flawed design choices were made in arriving at the Shuttle's final configuration:

"(1) Wings and landing gear are the heaviest of all possible methods of recovery.

"(2) Parallel staging is less efficient than tandem. More importantly, it also prevents the upper-stage engine from being optimized for vacuum operation. [He details this at some length, pointing out that it's particularly true for hydrogen-fueled engines.]

"(3) Use of two boosters doubles the probability of catastrophic failure. Multiple main engines increase probability of catastrophic failure by a factor of three, even though they may reduce the probability of noncatastrophic failure.

"(4) Opting for segmented booster cases increases the probability of case failure by unnecessarily complicating case design. Monolithic cases were proposed but rejected because Thiokol, a Utah company with no access to water transportation, had to propose a take-apart design.

"(5) Putting a crew on the first flight requires a very high reliability based on ground tests alone. A more sensible procedure would have been to fly the vehicle unmanned for cargo missions until an adequate degree of reliability could be demonstrated, as was done with the Saturn V (the Soviets, incidentally, did fly their shuttle Buran, for the first and only time, without a crew).

"(6) Use of solid propellants in the boosters minimizes the savings that can be had through recovery and reuse. Pressure-fed liquid-propellant boosters, as initially recommended by NASA-Marshall, would have required little more than a wash-down and refueling before reuse. Solids require disassembly and return to the factory, along with replacement of many parts. The cost of solid propellants runs about $7/lb vs. an average of about 10 cents for liquids.

"(7) Throwing away the largest part of the system, the main fuel tank, adds about $50 million to the cost per flight.

"(8) People and cargo should never be mixed. Payloads to be transported to orbit, even for missions requiring a human presence, are 95% 'stuff' and at most only 5% 'meat.' The provisions and safety requirements for the latter cost an order of magnitude more than for the former. Mixing the two burdens cargo flights with the same elaborate safety measures required for people."
________________________________

Some of Truax's arguments are open to question -- in particular, his belief that rockets should not only be recovered in but also launched from the ocean, and his belief that pressure-fed stages are better than turbopumps. (He got five approving letters from engineers in the April issue of the magazine, but also one detailed critique of that particular idea by an engineer who had worked on pressure-fed boosters and found out the hard way that they must be heavy and thus inefficient.) It may also be workable and economically effective to use the same booster for people and cargo, provided that any manned capsule is equipped with an escape rocket (which by itself will massively increase the safety of any manned mission, without having to go through the phenomenal expense of man-rating the booster to the degree that's necessary for the Shuttle).

And he was saying all this, loudly, in the 1970s, proposing an alternative to Shuttle called "Sea Dragon" that would have had these traits.
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dvandorn
post Feb 22 2006, 03:43 PM
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And you can add to Truax's comments the comment, made in the mid-90's by one of the main NASA designers of the Shuttle system, that they "got exactly the system (they) wanted." He went on to say that the designers knew exactly how infrequently this Shuttle would be able to fly, and how expensive it would be, and that's exactly the system they wanted. (If someone could recall the designer's name for me, that would be appreciated -- I just don't recall it at the moment.)

I seriously disagree with some of Truax's comments, and I also believe that his comments were designed solely to attack a competing concept -- i.e., he, Truax, was looking at getting a few billion dollars from the government in his *own* pockets, which motivated him to make some unsubstantiable attack statements. Obviously, his attacks didn't work, probably because everyone at the time realized that he had an axe to grind on this particular issue.

However, I take *strong* exception to the statement earlier in the thread that eliminating manned space flight is one of Griffin's goals. I dare anyone to produce a statement by Griffin that supports this. I also put up against it the fact that Griffin put a Shuttle servicing mission of Hubble back on the schedule, even after O'Keefe and his minions had killed it.

Once again, I will say it -- eliminate manned spaceflight from the U.S. budget, and you'll be left with Russia, ESA and JAXA for *all* of your unmanned probes. Congress will *never* see the sense of continuing unmanned exploration unless there is also a manned space presence; they will see bowing out of manned spaceflight as a statement of our intention to abandon space exploration entirely. If you sell the first, the second will follow automatically. So, if you want to see American unmanned spaceflight brought to a complete halt, go ahead and lobby for an end to American manned spaceflight.

Pardon me if I don't join y'all in that.

-the other Doug


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mcaplinger
post Feb 22 2006, 04:03 PM
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QUOTE (BruceMoomaw @ Feb 22 2006, 03:21 AM) *
An excellent case can be made that the basic concept of the Shuttle was disastrously dumb-ass from the very beginning -- and Robert Truax made it in his January 1999 "Aerospace America" article...


Regardless of the merits of Truax's technical points, the first rule of aerospace is that paper studies like his Sea Dragon are worthless by themselves. Until you have actually built, tested, and flown a system multiple times, you are only extrapolating based on incomplete data how it will perform, how well, and how cost-effectively. Talk is cheap, and aerospace is riddled with large and embarrassing failures based on ideas that seemed great on paper.

There's no shortage of people who trash the Shuttle with 20-20 hindsight, but the engineers who designed and built it did the best job they could under the technical and budgetary constraints at the time, and it's quite an achievement in that light. Within the limits of statistical error, its failure rate matches pretty well with the original honest assessment of 1 in 100 flights. If you want higher reliability than that, you'd better be prepared to pay for it, in money or capability or something.


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Bill Harris
post Feb 22 2006, 05:24 PM
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It will be an endless debate of whether or not the Space Shuttle is/was a good idea or not. Nonetheless, it has been a part of the US space program for two decades and it stands on it's own, good or bad.

However, my view is that it should not have been the _sole_ vehicle for US manned spaceflight and LEO cargo. We should have developed and utilized a "Gemini/Apollo/Soyuz" vehicle for routine manned launches, and an unmanned cargo ship for cargo. What we ended up doing with the Shuttle is equivalent to a young family selling it's Toyota sedan and buying a Winnebago RV as it's sole transportation.

The Shuttle program has been wonderful, but tunnel-visioned.

--Bill


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Bob Shaw
post Feb 22 2006, 10:55 PM
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QUOTE (dilo @ Feb 22 2006, 08:46 AM) *
Perhaps slightly OT, I knew the Sanger project and I remember also a modern spaceplane project called "Sanger", in honor of this projectist. In the image I saw, it was a beautiful, very aveniristic model but I cannot find any info on that. Someone can help?



Marco:

Try looking at:

http://www.astronautix.com/lvs/saegerii.htm

Bob Shaw


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Guest_BruceMoomaw_*
post Feb 23 2006, 01:00 AM
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QUOTE (mcaplinger @ Feb 22 2006, 04:03 PM) *
Regardless of the merits of Truax's technical points, the first rule of aerospace is that paper studies like his Sea Dragon are worthless by themselves. Until you have actually built, tested, and flown a system multiple times, you are only extrapolating based on incomplete data how it will perform, how well, and how cost-effectively. Talk is cheap, and aerospace is riddled with large and embarrassing failures based on ideas that seemed great on paper.

There's no shortage of people who trash the Shuttle with 20-20 hindsight, but the engineers who designed and built it did the best job they could under the technical and budgetary constraints at the time, and it's quite an achievement in that light. Within the limits of statistical error, its failure rate matches pretty well with the original honest assessment of 1 in 100 flights. If you want higher reliability than that, you'd better be prepared to pay for it, in money or capability or something.


The trouble with Shuttle is not its reliability rate -- a failure rate of less than 2% does compare well with any unmanned booster. The trouble, as should be obvious, is everything ELSE about it: its disastrously low cost-effectiveness per kg of payload carried, and, oh yes, the fact that when it fails it usually kills people, which another type of booster would not. (Had the Shuttle been a CEV-type design -- that is, a reusable booster carrying a capsule with an escape rocket -- it would have killed NOBODY by this point. The Columbia accident would never have occurred; in the case of Challenger the escape system, if designed with even minimal competence, would have detected the leak and rocketed the crew to safety about 15 seconds before the explosion.)

In fact, these flaws -- basic to its fundamental design -- WERE clear to a lot of people at the time besides Truax, which is why NASA had to lie about the Shuttle to a degree that would have made Baron Munchausen blush to get it through Congress. Robert Thompson -- the program manager at the time -- actually guffawed while he was telling CAIB about the size and absurdity of the claims NASA was successfully feeding to Congress at the time: "Hell, anybody with any sense knew we'd never fly that often." He thought it was a terrific joke.

And the responsibility for the crime (which is not too strong a word for it) lies not with engineers frantically trying to do the best they could with such an absurd design -- it lies with the leadership of NASA, who deliberately, from the very start, set out to create a massively expensive and unjustified program to try and keep the agency's funding level as close to the bloated levels of the Moon Race as they possibly could, and who were willing to tell absolutely any lie necessary to achieve that goal. As Reagan's science advisor George Keyworth said during his frantic but futile attempt to keep Reagan from swallowing NASA's similar outrageous lies about the cost and utility of the Station: "Every government agency lies part of the time, but NASA is the only one I know that does so most of the time." (He could have added that the reason for this is simply that it has far more reason to lie than any other government agency, because its total spending level has made far less sense than that of any other agency since the historical freak of the Moon Race ended.)

The one piece of actual new news in Thompson's testimony was his revelation that President Nixon, instead of being another victim of NASA's scam, was in on it from the start. He knew that the Democratic Congress would never approve what he and NASA really wanted -- a super-expensive Shuttle/Station program -- so he collaborated with NASA's lies about the supposed economy of the Shuttle as a cargo carrier, in order to increase the chances that Congress would agree to pony up the additional money for the Station before the end of his second term. Watergate put a stop to that plan; but NASA kept it in mind, and finally successfully staged part 2 of their Master Plan by exploiting the gullibility first of Reagan, and then of Al Gore.
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Guest_BruceMoomaw_*
post Feb 23 2006, 01:17 AM
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You can find an overall summary of Thompson's CAIB testimony in my May 2003 "SpaceDaily" article: http://www.spacedaily.com/news/shuttle-03p1.html . When I get another few minutes free, I'll locate the URL of the transcript of all his testimony.
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Guest_BruceMoomaw_*
post Feb 23 2006, 01:29 AM
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QUOTE (dvandorn @ Feb 22 2006, 03:43 PM) *
Once again, I will say it -- eliminate manned spaceflight from the U.S. budget, and you'll be left with Russia, ESA and JAXA for *all* of your unmanned probes. Congress will *never* see the sense of continuing unmanned exploration unless there is also a manned space presence; they will see bowing out of manned spaceflight as a statement of our intention to abandon space exploration entirely. If you sell the first, the second will follow automatically. So, if you want to see American unmanned spaceflight brought to a complete halt, go ahead and lobby for an end to American manned spaceflight.

-the other Doug

_______________________________

Why? ESA and (to a lesser extent) JAXA have fairly big unmanned space programs without much if any manned component. Why should Congress be unwilling to follow suit? (Especially given the continued existence of its very large Space Pork Faction, who would be eager to keep total space spending as high as possible and would therefore certainly support an enlarged unmanned program to partially compensate.)

What is true is that we might very well end up with a shrunken unmanned space program, along the lines of ESA (although probably not nearly that small, for the reason given above). So what? The right question is not what I and the rest of you in this little group get a kick out of watching -- the right question is the extent to which space exploration really is justifiable, on practical, rational and moral grounds, as opposed to other uses for the money. To the extent that it has practical benefits, it should compete on an equal platform with other governmental spending on engineering projects and scientific research. To the extent that it's a form of public entertainment, the public should decide how much of their taxes they want spent for that purpose.
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post Feb 23 2006, 01:38 AM
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QUOTE (BruceMoomaw @ Feb 23 2006, 01:29 AM) *
Why? ESA and (to a lesser extent) JAXA have fairly big unmanned space programs without much if any manned component. Why should Congress be unwilling to follow suit?

Because the vast if not overwhelming majority of their consituents don't care what "ESA and (to a lesser extent) JAXA" do.
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lyford
post Feb 23 2006, 02:06 AM
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QUOTE (AlexBlackwell @ Feb 22 2006, 05:38 PM) *
Because the vast if not overwhelming majority of their consituents don't care what "ESA and (to a lesser extent) JAXA" do.

I would wager the vast majority of them would not even know what ESA and JAXA are...... mad.gif


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mcaplinger
post Feb 23 2006, 03:47 AM
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QUOTE (BruceMoomaw @ Feb 22 2006, 05:00 PM) *
Had the Shuttle been a CEV-type design -- that is, a reusable booster carrying a capsule with an escape rocket -- it would have killed NOBODY by this point. The Columbia accident would never have occurred...


No doubt this explains why the Russians have never lost people on Soyuz flights. (Well, no: four people dead in two entry accidents. Would you argue that the US would never have accidents like those? We came fairly close to losing the US crew of Apollo-Soyuz to an accident similar to Soyuz 11.)

Forgive my lack of confidence in your ability to flawlessly predict these alternate-history outcomes. And I'm not sure what this CEV-type vehicle would have been doing; certainly neither DOD nor NASA had any interest in such a thing in the time frame we're discussing. For that matter, I'm not sure what the current CEV is supposed to be doing either smile.gif


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Guest_BruceMoomaw_*
post Feb 23 2006, 04:37 AM
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QUOTE (mcaplinger @ Feb 23 2006, 03:47 AM) *
No doubt this explains why the Russians have never lost people on Soyuz flights. (Well, no: four people dead in two entry accidents. Would you argue that the US would never have accidents like those? We came fairly close to losing the US crew of Apollo-Soyuz to an accident similar to Soyuz 11.)

Forgive my lack of confidence in your ability to flawlessly predict these alternate-history outcomes. And I'm not sure what this CEV-type vehicle would have been doing; certainly neither DOD nor NASA had any interest in such a thing in the time frame we're discussing. For that matter, I'm not sure what the current CEV is supposed to be doing either smile.gif


"Flawless prediction" has nothing to do with it. The types of accidents that happened on Soyuz 1 and Soyuz 11 were the result of the incredibly shoddy design and assembly techniques used by the Soviets, as opposed to the US -- and those kinds of accidents, and ALL the kinds of dangerous accidents suffered by US capsule missions, are the sorts of things that could also have happened on a Shuttle. I never said that capsules equipped with escape rockets are totally safe; I said that they are by their basic nature much safer than a large winged craft, and the fact that neither fatal Shuttle accident would have happened on a capsule vehicle is further proof of that.

You are, of course, right that NASA had no interest in that kind of vehicle in that time frame -- because, and only because, there wasn't enough taxpayer-provided money in it. As for the DoD, see my article for one other fascinating little tidbit from Thompson's testimony:

"We then [after Nixon's secret decision] undertook obviously to build the Shuttle first, and then a modular, zero-gravity space station second...As the thing evolved, we started with the Shuttle, and the requirements for the Shuttle were driven 99 percent by what we wanted to do to support the space station. It also happened to give the Air Force the kind of payload volume and the kind of capability they wanted, although they really wanted to be at higher orbits for their work.

"So the Air Force came in and said, 'We will plan to use the Shuttle, and we will also take on the task of building the Interim Upper Stage, which was part of the low-Earth-orbital infrastructure. So NASA embarked on the Shuttle. It wasn't necessary to commit to a space station at that time because the Shuttle had to be built and operational before you commit to the space station, and the President at that time -- Nixon -- had other things on his mind. He didn't get up and make a great big speech about low-Earth-orbital infrastructure.' "

Thus we have further confirmation that the Air Force didn't demand that specific design for the Shuttle; NASA told them that it was a magic Dr. Feelgood elixir for all the Air Force's needs (and so safe, too -- only a 1 in 100,000 chance of a launch accident!); and so the Air Force agreed to go along, although even after that sales job it wasn't really what they wanted. By 1985 -- before the Challenger accident -- they had already realized that NASA had royally screwed them; the vehicle wasn't even remotely as capable and cheap as NASA had promised it would be, and their own estimates gave it a 1 in 56 chance of launch failure. So, thank God, by mid-1985 they had already demanded that the Titan production line be started up again -- and if they hadn't done that, the Challenger disaster would have had much worse consequences for this country than it actually had.

As for what the current CEV is "supposed to be doing": why, it's supposed to be doing exactly what Shuttle and Station were always supposed to do -- siphon massive amounts of taxpayer money into NASA and into the Space Pork Complex. Like them, it has no other real purpose. But at least it's safer and more economical than they are, and it has the potential to gradually evolve into future types of manned vehicles that might someday actually be useful for something.

QUOTE (AlexBlackwell @ Feb 23 2006, 01:38 AM) *
Because the vast if not overwhelming majority of their constituents don't care what "ESA and (to a lesser extent) JAXA" do.



Of course, the same thing is true of the vast majority of European and Japanese citizens. Lo and behold, their nations have fair-sized space programs anyway. So I repeat: why wouldn't the US? Are we supposed to believe that the US government and its citizens are THAT idiotically addicted to purposeless manned space flights?

Incidentally, the Huygens and Hayabusa missions seem to have attracted considerable interest and support from European and Japanese citizens, without a single astronaut being involved -- just as the Voyager, Hubble and MER missions did here.
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