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Was the Space Shuttle an inherently bad idea?

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Well, I think that the Concept and the execution were a good idea, but as others mentioned before, only for specific use.

Here's what I mean:

Before the shuttle, We had rockets, helicopters, and planes. The shuttle allowed us to commit some research towards high altitude avionics, which in turn means that our air breathing planes may have benefited from its creation, making them safer, more fuel efficient, and more capable than before the shuttle program was put in place. I'm not saying this is fact, I have no evidence to back it up, but as they had to deal with things like low-null pressure environments, high heat from re-entry, and many other challenges, this data gathered could have been used in the creation of aircraft that is in use today, with greater capabilities than before.

So my point is, regardless of the results we have now, and it being branded somewhat of a failure, Knowledge gained from it cannot be un-learned. We gained some insight on design from its "failure". That in itself makes it worth the cost In my eyes, because it will allow us to improve upon for future missions.

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Borrowing from the Buran is just indirectly borrowing from the Shuttle. The Buran became a Russian Space Shuttle copy, the only difference being possible unmanned mission launches (I don't regard an unmanned test launch an example of unmanned abilities), and a possibly more rugged design (while Russia is known for lower tolerances for better durability, I have yet to see the design specs on the Buran to see if that is actually so).

Buran did not have reusable main engines the external tank on the shuttle was an actual stage. Think this was of technical reasons, they was not able to make rocket engines who could be used many time at least not in the time frame given. This had the benefit that it would be far easier to use the setup as an very heavy lifter.

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It was a job program and an ideal way of transfering federal money to future voters and big guys in the aerospace industry.

So I say mission accomplished :P BTW doesn't this remind you of something?

That's just mean :D

However true, yes its smart to add future capabilities but not to make an system to do anything, as other say, an smaller shuttle would work better. it would still have the crew transport, repair and assembly functions.

It would loose the capability to launch and module to IIS and mount it, the module would require its own launch.

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While not ideal, the segmented SRBs weren't actually a serious problem, and Challenger wasn't a result of any particular flaw of the SRBs or the shuttle itself (Yes, yes. O-Rings, but read on). Unlike Columbia, the Challenger disaster was due purely because of horrible management on NASA's part, and could have been avoided by simply postponing the launch for a day or two.

The SRB's had been designed and tested around specific launch conditions, including the temperature. On the day of the Challenger disaster the temperature at the launch pad was well below the minimum rated temperature of the SRBs. The MT engineers recognized that the O-Rings were well outside of their rated safe temperature and expected that they would be brittle enough to crack, and as such, completely unsafe to launch. The engineers obviously urged NASA to wait until a warmer day to launch.

NASA management knew about all of this as they had the SRB design specs and had consulted with Morton Thiokol about the launch temperature that day, but in the end they decided that since the SRBs hadn't failed yet, it was completely impossible for them to ever fail, no matter the launch conditions. This is a distressingly common thought process in NASA it seems. Anyway, with that in mind they decided to disregard not just the original design limitations of the SRBs but also of the engineers who actually built the things and launch anyway. As a result of NASA's management, Challenger and her entire crew were lost .

While large monolithic boosters could probably have handled a launch that day due to the lack of O-Ring seals, the fact of the matter is, they shouldn't have launched that day at all, and they knew it beforehand. As such, it's not entirely fair to claim that the SRB's were inherently unsafe. Anything can, and likely will, fail if you try to use it well outside of it's original design limitations.

Sorry, I have to disagree. With the monolithic SRBs they would have been able to launch at that temperature, or any other temperature, because they would not have had a temperature restriction based on the limitations of the o-ring seals. The segmented boosters were inherently less safe than the monolithic boosters because their design involved more parts, more joints, and more failure modes. There had been multiple cases of partial o-ring failure before the accident. It was really only a matter of time before some outside factor (temperature, wind shear stress, undiscovered defect, etc.) combined with one of these partial failures to produce a disaster. The fact that the Challenger accident could have been avoided by delaying the launch doesn't change that.

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Sorry, I have to disagree. With the monolithic SRBs they would have been able to launch at that temperature, or any other temperature, because they would not have had a temperature restriction based on the limitations of the o-ring seals. The segmented boosters were inherently less safe than the monolithic boosters because their design involved more parts, more joints, and more failure modes. There had been multiple cases of partial o-ring failure before the accident. It was really only a matter of time before some outside factor (temperature, wind shear stress, undiscovered defect, etc.) combined with one of these partial failures to produce a disaster. The fact that the Challenger accident could have been avoided by delaying the launch doesn't change that.

All of those other cases were self-solved by the o-ring itself. The temperature conditions failed to allow the o-rings to self-repair, causing the disaster.

You can argue all you want that they would have eventually gone, but that's just a fact of it being a rocket, and an uncontrollable one at that.

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All of those other cases were self-solved by the o-ring itself. The temperature conditions failed to allow the o-rings to self-repair, causing the disaster.

You can argue all you want that they would have eventually gone, but that's just a fact of it being a rocket, and an uncontrollable one at that.

But the fact that you are all ignoring is that if they had gone with the Aerojet proposal (which, I will point out again, was actually less expensive than the MT proposal), then the o-rings would never have failed because there would have been no o-rings! I'm not saying that the Aerojet design couldn't fail, I'm saying that it would have been less prone to failure and that the specific failure mode that destroyed Challenger would have been impossible. And the Aerojet proposal wasn't discarded because it was inferior or more expensive, it was discarded because a senator wanted to use his political influence to funnel more Federal money to his home state. Challenger was destroyed by politics, plain and simple.

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Sorry, I have to disagree. With the monolithic SRBs they would have been able to launch at that temperature, or any other temperature, because they would not have had a temperature restriction based on the limitations of the o-ring seals. The segmented boosters were inherently less safe than the monolithic boosters because their design involved more parts, more joints, and more failure modes. There had been multiple cases of partial o-ring failure before the accident. It was really only a matter of time before some outside factor (temperature, wind shear stress, undiscovered defect, etc.) combined with one of these partial failures to produce a disaster. The fact that the Challenger accident could have been avoided by delaying the launch doesn't change that.

No. The SRBs were safe as long as they were used within their design tolerances. Yes, the design tolerances were possibly smaller because they were more complex, but it's nothing short of idiotic to launch outside of those design tolerances in the first place, a lesson that NASA learned at a heavy cost. Claiming that the SRB's were inherently flawed because they were unsafe when used outside of their tested and rated design tolerances is akin to saying that the Saturn V was unsafe because it wasn't rated to be launched in the middle of a hurricane.

Also, a key point I think you're failing to account for is that the SRBs are some of the largest solid rockets ever manufactured, and are surely the largest production solid rockets. Even Aerojet had extremely limited experience in building such large monolithic boosters. So there would have been additional research and development costs associated with that choice. Furthermore, there were some fairly serious flaws with the initial Aerojet proposal, such as insufficient case strength to support the shuttle stack and a projected inability to survive a water landing intact. Could those have been corrected? Sure, but again, that adds to the cost, and contrary to your earlier assertion, Aerojet was already far from being the cheapest bidder. MT was the cheapest by around 122 million, followed by Lockheed Martin, who had proposed their own segmented booster design.

I'm not claiming that the SRBs were absolutely perfect, obviously they weren't, however, I don't think it's fair to condemn them for a single failure in which they were knowingly used outside of their design tolerances. At most, those design limitations should have been a minor annoyance to NASA since it limited the number of launch days they had available. However, by ignoring them NASA turned those design limitations into a disaster that destroyed a 1.7 billion dollar orbiter and cost 7 astronauts their lives.

From my perspective, that's a flaw with NASA management. Not with the boosters.

Source - "The Challenger Launch Decision: Risky Technology, Culture, and Deviance at NASA" By Diane Vaughan

Edited by Firov
Forgot to add source info

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I wouldn't nitpick too much about the o-rings. Nasa made a wrong decision that day which is very tragic.

What can be considered reckless however is the fact that a loss of more than one SSMEs during the first 350 seconds and major malfunction of either SRB would have meant loss of crew. This was known and accepted as part of the design. Arrogance?

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I wouldn't nitpick too much about the o-rings. Nasa made a wrong decision that day which is very tragic.

What can be considered reckless however is the fact that a loss of more than one SSMEs during the first 350 seconds and major malfunction of either SRB would have meant loss of crew. This was known and accepted as part of the design. Arrogance?

Interesting bit of trivia. After the post-Challenger disaster structural enhancements, the shuttle crew could have survived the failure of all three SSME's, even before T+90 seconds. At least in theory. The SRB's actually provided enough steering authority for the entire shuttle stack during the initial ascent. It's questionable if the structural braces could actually have held up under those kinds of stresses though, and even if they did it's unlikely they would have been able to get the orbiter back to Kennedy space center for a safe landing. Though the crew would at least have been able to bail out after SRB separation.

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All of the partial failures prior to Challenger had taken place during launches that met with the design tolerances. The fact that the joints were flawed was well know within MT, and they had already convened an engineering group to redesign the joint to prevent o-ring failure due to joint rotation before the Challenger accident. But MT management made a joint decision with NASA management to continue the launch schedule despite the risks.

As for the Aerojet bid, I have no idea where you're getting your info. Mine comes from here: http://astronautix.com/engines/srb.htm, which is sourced from a book written about Aerojet by the people who were there. MT's bid was fourth out of four in the first round of bidding. After Frank Moss spoke to NASA and Nixon, they discarded the first round and opened a second round of bidding and MT miraculously won. Lockheed actually filed a protest, to no effect.

And for the record, Aerojet was the only company in the bidding that had experience designing and building solid rocket motors of that magnitude. They built and test fired a 260-inch SRM at their Florida facility in 1965 that actually generated about 50% more thrust than the Shuttle SRB. It was the largest SRM ever constructed, and generated more thrust than any other rocket motor (solid or liquid) in history. http://astronautix.com/engines/aj2602.htm

No doubt that NASA management made bad decisions leading up to the Challenger accident. I don't in any way excuse them. But the fact is that if the Shuttle had used monolithic boosters, that accident wouldn't have happened.

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@Firov

Yea, but the pre Challenger design was not some prototype but meant to be the final "product". The safety improvements after the disaster were on top of that existing design, and some of the abort modes can be called adventurous to say the least.

Any major sputtering in one of the SRBs would have always killed the crew (SRBs have a 1% failure rate according to Wikipedia), same with any explosion on the launchpad.

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As for the Aerojet bid, I have no idea where you're getting your info. Mine comes from here: http://astronautix.com/engines/srb.htm, which is sourced from a book written about Aerojet by the people who were there. MT's bid was fourth out of four in the first round of bidding. After Frank Moss spoke to NASA and Nixon, they discarded the first round and opened a second round of bidding and MT miraculously won. Lockheed actually filed a protest, to no effect.

I cited a source, though it was an edit so you might have missed it. Anyway, it's in "The Challenger Launch Decision: Risky Technology, Culture, and Deviance at NASA" By Diane Vaughan. There's a chapter on the SRB bid process.

Anyway, the previous "failures" were all "self healing", just as the Challenger disaster would have been had they launched inside of the approved design tolerances for the SRBs.

Also, you're of course referring to the AJ-260-2 rocket motor, which was built and tested by Aerojet. I actually knew about that, but keep in mind that not only were those prototypes they were also less than half the length of the shuttle SRBs. They never built a full scale unit. The major difficulty of building large monolithic rocket motors isn't so much in diameter, but length. I have no doubt that they could have done it, of course, as they had more experience with solid rockets than anyone, but it would have taken time, plus plenty of research and development. Plus, like I said, their initial proposal did have some serious flaws according to my source such as a lack of structural strength in the case to support the entire shuttle stack, and the inability to survive a water landing intact.

No matter which path they took, there would have been problems. In the case of Challenger, the "problem" was known beforehand and completely avoidable.

@Firov

Yea, but the pre Challenger design was not some prototype but meant to be the final "product". The safety improvements after the disaster were on top of that existing design, and some of the abort modes can be called adventurous to say the least.

Any major sputtering in one of the SRBs would have always killed the crew (SRBs have a 1% failure rate according to Wikipedia), same with any explosion on the launchpad.

Granted. However, most spacecraft that have extended lifespans are upgraded over time. Just look at Soyuz for an example. It's been upgraded how many times now over it's ~40 year lifespan? Originally, it wasn't even meant to carry 3 astronauts. So upgrades to a spacecraft over time aren't unexpected, and certainly not necessarily indicative of any particular critical design flaw. As for SRB reliability, the only failure I know about is the one we've been talking about, in which it was used outside of it's design tolerances. But anyway, yes, had they screwed up the casting of the fuel grains for one of the SRBs, it would have resulted in the loss of the vehicle and crew.

Edited by Firov

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@Firov

Design evolution over time is one thing, hotfixing forseeable problems each time there is a worst case incident is something different :)

True enough. NASA seemingly only improved the safety systems of the shuttle after a major disaster. Both with Challenger and again with Columbia. However, most of the safety improvements wouldn't have helped in Challenger's case anyway. Well, aside from the double o-rings and o-ring heaters, of course. For the most part, it was a general improving of the Shuttle design. It just so happens that these general improvements always occurred after a major disaster, likely because the shuttle fleet was grounded anyway. May as well make what improvements you can while you have a chance.

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But the fact that you are all ignoring is that if they had gone with the Aerojet proposal (which, I will point out again, was actually less expensive than the MT proposal), then the o-rings would never have failed because there would have been no o-rings! I'm not saying that the Aerojet design couldn't fail, I'm saying that it would have been less prone to failure and that the specific failure mode that destroyed Challenger would have been impossible. And the Aerojet proposal wasn't discarded because it was inferior or more expensive, it was discarded because a senator wanted to use his political influence to funnel more Federal money to his home state. Challenger was destroyed by politics, plain and simple.

You can't say it was less prone to failure, because we don't know if parts of the MT design were more flawed than the Aerojet design.

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The most frustrating aspect is during the 60's NASA was able to design and build 3 highly successful LEO launch systems with the technology at hand, namely Mercury, Gemini and Apollo all within 7 years of each other.

Gemini is particularly frustrating as it had by far the biggest growth potential of all 3 systems. If you look at some of the follow on proposals, Gemini Blue, Big Gemini it makes you want to f**king weep, so many possible opportunities we missed.

But no, NASA is back trying to design a one size fits all system again.

It's almost as if we didn't learn anything from Shuttle :-(

Edited by Simon Ross

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@Firov

Design evolution over time is one thing, hotfixing forseeable problems each time there is a worst case incident is something different :)

But this sort of thing happens in aviation all the time. Why should spacecraft be any different? Every single commercial aircraft type currently in service (including the new 787) has a long list of airworthiness directives. Airworthyness directives are a regulatory mechanism that allow regulatory authorities like the FAA to force operators to modify their in-service aircraft.

Sometimes, the "worst case [accident]" that necessitated the airworthiness directive didn't even happen to the aircraft type that must be changed. For example, a lot of armchair aviation buffs like to hate on the DC-10 because of the Turkish Airlines crash, but subsequent to that crash, the FAA issued AD 75-15-05 that required operators of wide body Boeing, McDonnell Douglass, Lockheed and Airbus aircraft to install blow-out panels in the cabin floors so that the floors wouldn't collapse in the event that the aircraft depressurized above or below the floor. In other words, one of the design flaws that contributed to the Turkish Airlines DC10 crash existed in all wide body aircraft at the time, and all had to be modified after the problem was recognised.

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@PakledHostage

Don't fool yourself. The SS system was not an aircraft just because one part had wings. I rather believe it had wings so that people would belive it was as reliable as a 747.

It wasnt safe. SRBs are fireworks. The whole system was complex and its creators knew that there was a certain failure rate, somewhere in the 1% range. They ignored it and did not design ANY safety systems for the first few minutes of flight.

A cilvil airliner counts as a death trap if 1 in 1,000,000 flights crash. The shuttle blew up after ~50 flights (1% preicted SRB failure times 2 SRBs, what a coincidence) welcome to rocketry. This is what I called a foreseeable problem earlier, problems in civil aviation aircrafts were all unforeseeable.

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I don't think any astronaut would disagree that spaceflight is a risky business, and it will be for a long time. Be it solid or liquid, winged or capsule. What PakledHostage is showing is similarities on the operational procedures that, yes, in some places are quite similar between the aeronautics and aerospace industry.

The biggest flaws of the shuttle were not in the spacecraft itself, but in the operational procedures given that, as time goes by, people get complacent and less strict in their routines. Still, even in its lowest points (Apollo 1, Challenger, Columbia), NASA still had a higher level of operational strictness than any airline company that carries millions of people every year, and yet most don't complain and feel safe inside their planes. It's just that a spacecraft is a few orders of magnitude more complex so that, even when you are alert, things can get ugly.

Now to the spacecraft itself, I wonder if NASA didn't have pursued the winged reusable vehicle. Now there would be hundreds of "experts" arguing that a winged reusable vehicle would be much better than building the same rocket over and over again. If anything, the Shuttle program teached what works and what doesn't so there is a huge head-start in future attempts at this kind of design. But, for me, the bad ideas are the ones you didn't pursued.

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@PakledHostage

Don't fool yourself. The SS system was not an aircraft just because one part had wings. I rather believe it had wings so that people would belive it was as reliable as a 747.

It wasnt safe. SRBs are fireworks. The whole system was complex and its creators knew that there was a certain failure rate, somewhere in the 1% range. They ignored it and did not design ANY safety systems for the first few minutes of flight.

A cilvil airliner counts as a death trap if 1 in 1,000,000 flights crash. The shuttle blew up after ~50 flights (1% preicted SRB failure times 2 SRBs, what a coincidence) welcome to rocketry. This is what I called a foreseeable problem earlier, problems in civil aviation aircrafts were all unforeseeable.

Now you're just being obtuse. As has been pointed out, the SRB that failed in the Challenger disaster only failed because it was knowingly used well outside of their design specifications. They were, in fact, probably the most reliable system on the entire shuttle, since that was their one and only real failure. To put things into perspective, there were 135 shuttle launches. Each launch obviously consisted of 2 solid boosters, so a total deployment of 270 SRBs. Through all of that, exactly one SRB failed, during the Challenger disaster. Now, I punch those numbers into my calculator, it makes a happy face. Seriously. That's a failure rate of 0.37%. Note that decimal. That's about a third of a percent. And that failure ONLY happened because the NASA management didn't listen to TM's engineers or bother looking at the spec sheet on the SRBs. I wish my car were that reliable.

So yeah, the Shuttle was hardly a "death trap", as you put it. It had 2 fatal failures in it's history, one of which arguably wasn't a fault with the Shuttle itself. That's at least as good as Soyuz, despite a massively more complex design.

Plus, the safety systems of the shuttle were continuously upgraded throughout it's life, usually after one of the fatal accidents, but again, I expect that's simply because they already had grounded the shuttles during those periods and so it made an opportune time to upgrade the entire fleet at once.

Finally, you seriously believe the wings were the result of NASA wanting to "fool" people into thinking it was a 747? No, the large delta wings were a direct result of the Air Forces request for a ~1000 mile cross range ability, which they requested so that so it could be launched into a polar orbit, immediately deploy a military spy satellite, and then return to base before it orbited again so as to avoid Soviet anti-satellite weapons.

Edited by Firov

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If you guys want someone to blame for the wings on a spacecraft, blame the Germans - specifically, Eugen Sanger and its "Amerika Bomber". The fact that most of the scientists and engineers that worked with Sanger went to the US to work for Bell, North American and other US companies didn't helped to not develop a winged spacecraft. Not counting Von Braun itself, which "master roadmap for space", even before Apollo, envisioned a reusable shuttle building a space station.

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@PakledHostage

Don't fool yourself. The SS system was not an aircraft just because one part had wings.

But that wasn't my point. My point was that even engineering designs such as commercial airliners that are less complex than spacecraft often require "hotfixes" (to use your word) in service. This despite the fact that they are built to operate in a somewhat more forgiving environment than spacecraft and are designed to comply with a large body of regulations that evolved as a result of decades of experience.

I intentionally chose the example of AD 75-15-05 because it relates to a design problem that existed in all widebody aircraft designs at the time. In hindsight, it is pretty obvious that suddenly exposing the cabin floor to a differential pressure of 6-8 psi between its two sides could cause it to collapse, but nobody took the possibility seriously enough to mandate new design requirements until after the Turkish Airlines accident. This closely parallels the debate that is going on in this thread, which is why I mentioned it.

Edited by PakledHostage

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I tried to find shuttle alternatives and that's what I found:

ClirtJk.jpg

.gif with different configurations: http://i.imgur.com/028Wo3s.gif

(launch configuration - wings retracted, descent configuration - wings deployed,landing configuration - landing gear deployed.

Landing on parachutes: http://i.imgur.com/PwHKK69.jpg (Who will say KSP is unrealistic?!:cool:)

That's ÃωÃÅ¡-Òß (russian letters)

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I tried to find shuttle alternatives and that's what I found:

http://i.imgur.com/ClirtJk.jpg

.gif with different configurations: http://i.imgur.com/028Wo3s.gif

(launch configuration - wings retracted, descent configuration - wings deployed,landing configuration - landing gear deployed.

Landing on parachutes: http://i.imgur.com/PwHKK69.jpg (Who will say KSP is unrealistic?!:cool:)

That's ÃωÃÅ¡-Òß (russian letters)

Not very realistic, is it? What's the economical motive for bringing back an empty payload bay if it comes back empty? And it pretty much exceeds the practical limits of modern parachutes, especially if you wanted to bring back a full-size payload.

You would be better off with a soyuz capsule for the crew and a disposable payload fairing underneath it.

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