I dunno about some of those points in that article there...
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Why was such a powerful rocket used only to reach very low orbits, where air resistance and debris would limit the useful lifetime of a satellite to a few years? Why was there both a big cargo bay and a big crew compartment? What kind of missions would require people to assist in deploying a large payload?
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When the shuttle program started, they wanted the vehicle to be economical. Therefore, they wanted the ability to launch bigger satellites, or numerous at a time. Also having the ability to retrieve them is a good way to rake in money from companies wanting to repair, rather than rebuild and relaunch. Also, at the time, apart from Skylab and Suylats (SP?) they didn't have much in the way to complete experiments in space. The shuttle enabled not only 7 astronauts aboard, but offered the crew roles of Mission Specialists - Space Scientists, who didn't have to give a stuff about flying the shuttle. I think they ran about 5 Space Lab missions where they used the shuttle cargo bay as a module for study.
I guess the idea of reusable also plays a big part. They wanted it to be able to glide back in like a plane. With the size available, it wouldn't be able to launch itself with its main engines. They needed the SRBs to carry the shuttle so it would have the ability to glide back.
So, it makes sense to have a large crew compartment and cargo bay - they wanted science and they wanted the money from companies.
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Why was the Shuttle intentionally crippled so that it could not land on autopilot?
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Because computers are temperamental. If one of the shuttles computers were to fail or have a bug which were to accidentally open the shuttles landing gears before reentry, they're screwed. The landing gear can only be shut on the ground by its engineers. I don't know why they made it like this, but there is probably some reason behind it. If the computer bugs out, then NASA just lost however many billion dollars an orbiter costs to make, not to mention possible cargo and crew.
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Why go through all the trouble to give the Shuttle large wings if it has no jet engines and the glide characteristics of a brick?
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The wings are not for flying, they are for landing. Adding jet engines would just be stupid - it would increase weight and size, and complexibility (which I believe the article goes on to say the shuttle is too complex as it is).
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Why build such complex, adjustable main engines and then rely on the equivalent of two giant firecrackers to provide most of the takeoff thrust?
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Because, regardless of how complex the main engines are, they are still not powerful enough to lift the shuttle all the way to orbit. Besides, the SRBs are one of the most reliable rockets ever used (or so I've read), and they are mostly reusable as well.
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Why use a glass thermal protection system, rather than a low-tech ablative shield?
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Once again, weight. The original plan was to use a thick alloy of some sort. Then they decided it would be way to heavy to be economical. So, they went to a much more precise and light method. Besides, I am getting the impression that the general public is taking the tiles to just some afterthought/thrown on thing. Each tile is individually placed on, and every one is cut individually for its space. They put ALOT of care into it.
The article goes on to speak about some Air force spy satellite thing. They ask why doesn't the shuttle have an air breathing engine...? Well... maybe because air breathing engines are only quite new, and the shuttle was designed and built in the 1970's?
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To further cut costs, and keep the weight from growing prohibitive, the Shuttle became the first manned spacecraft to fly without any kind of crew escape system, relying on certain components (solid rockets, wing tiles, landing gear) to function with complete reliability 3. NASA also decided not to make the Shuttle capable of unmanned flight, so that the first test flight of the vehicle would have astronauts on board. This was a major departure for the traditionally conservative agency, which had relied on redundant systems wherever possible, and always tested unmanned prototypes of any new rocket. It showed how confident NASA had grown in its ability to correctly predict, simulate, and design for high reliability
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I think they miss the point here. Lets face it, it doesn't really need a crew escape system. If during launch there is a problem, there isn't really much that can be done. Ejection seats wouldn't work for the average velocity - the shuttle travels too fast to make it safe. If there is a problem during reentry, same problem. If there is a problem after they've entered but leaves them unable to land, they do have protocol for that. Good 'ol fashion blowin' the hatch and ditching the shuttle. Also, they give the impression that the engines etc were not tested before hand? Not true. All rocket engines used on the shuttle were thoroughly tested before the launch. There were components that were not tested, but that was not due to 'laziness' but due to the incapability to do it without a launch. Besides, STS-1 DID have ejection seats etc just incase. Finally, if the SRBs stuff up, before they have reached the no-return barrier, they can ditch the SRBs and ET, and fly the shuttle back to KSC - no harm done.
I kinda phased out of the article after here. I quickly skimmed down the rest of the page, but didn't see anything that grabbed my attention.
I think one of the main things that everyone who is so keen to dismiss the shuttle program is forgetting is this: the shuttle is the first of its kind. I am sure that if the NASA people got together and redesigned it, they could get a much more useful vehicle that was safer and more economical too. The fact is, apart from Buran, no ones interested in an new shuttle type designs (which I believe is the right thing to do anyway). See Apollo. Everyone considers it reliable, useful etc. Why? Its third generation. The Mercury and Gemini's weren’t there for nothing (in fact, the Gemini's were built as a bridge for Mercury to Apollo, and is in some ways, more modern than the Apollo).
Oops, I didn’t realise how much I’ve written. I guess I kinda went off on a tangent! And its funny to think that I probably look all pro shuttle, when I actually believe we should mothball them all now, Launch the remaining components with unmanned rockets, give the Russians some extra money for their Progress craft and work like crazy on the CEV. I’m looking forward to what they come up with. (I must say, some of the designs I’ve seen are quite amazing
).
Ps: Everything I’ve written here is based on my memory of books I’ve read, articles, documentaries, other forums etc. Therefore, it may not all be 100% true.
Oh yeah - Go Discovery!
EDIT: Wow, I write slow. Since I started this post, there have been like 4 or so others posted
