posted
Yes, Columbia was the only shuttle that couldn't dock with ISS because it was too heavy - it couldn't reach ISS's orbit. The newer ones were built with the lessons learned from building Columbia, and thus were able to be built lighter.
posted
New shuttles? They're all well past expected operational lifetime at this point. The remaining three can all dock at ISS, though. In fact, one of the new safety policies is that a shuttle must be externally visually inspected before landing. Since doing that without the ISS is apparently difficult, they have to go there for every mission. And since they can't get to Hubble AND ISS in the same launch, Hubble is screwed.
The reason the shuttle is more expensive than originally planned is that they spend so much time checking every little thing. Wikipedia lists something like $100mil for actual launch preparations, and $400mil for inspections, per launch. Basically, at this point ISS makes the shuttle possible, and is the Shuttle's only reason for continued existence. FWIW, once the shuttle is back in operation, it should be able to take the completed European lab module to the space station.
I've been wondering: if they want the space station to have a craft capable of returning six people to earth safely... why not just leave a shuttle docked there once we have a replacement? It's pretty well the only thing ever built that has that capacity, and it's not like we'll be using them any more.
-------------------- "This is why you people think I'm so unknowable. You don't listen!" - God, "God, the Devil and Bob"
Registered: Mar 1999
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-------------------- "This is why you people think I'm so unknowable. You don't listen!" - God, "God, the Devil and Bob"
Registered: Mar 1999
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posted
I'm pretty sure the construction phase is over for good. NASA's website suggests differently, but I don't believe there are any concrete plans in place. Consider this Congressional committee report, which implies that as of September of last year no timeline had yet been drawn up about when and how exactly it would start up again. I mean, I don't know. I'll believe it when I see it, I guess.
Anyway, the shuttle could never be used as a lifeboat in the manner you suggest, for, I think, at least two reasons. One is that it simply isn't designed for it. Well, actually, that encompasses pretty much all of the reasons I can think of. The shuttle is heavier than a Soyuz, for instance, so how are you going to correct the station's orbit with this large mass hanging off to one side? The shuttle's thrusters weren't designed to move it plus a space station around. Not to mention the extensive maintainance you mention. True, most of that is probably due to the great stresses of launch and reentry, but the shuttles are finicky machines, and I don't think you could trust one not to simply fall apart when forced to be in space indefinitely.
Registered: Mar 1999
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posted
Add to those reasons that the ISS is constantly peppered with high-velocity space debris (far less so than Mir was though) and a permantly docked shuttle could be seriously damaged before too long.
I was watching Science Frontiers on PBS a few months ago and they were discussing the problem of space debris: they mentioned that during any EVA the shuttle acts as a shield for the astronauts because -at those speeds- even a small chip of paint or gold foil could kill an asrtonaut. Oddly, the shuttle uses it's heat shield to intercept any oncoming debris.
I wonder what experiments they proposed to do on the ISS that were not already performed on Mir... How did they sell the idea anyway?
-------------------- Justice inclines her scales so that wisdom comes at the price of suffering. -Aeschylus, Agamemnon
Registered: Aug 2002
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posted
God if only somebody had already designed and tested a dedicatedlifeboat. Can you imagine them cancelling a project like that after having already spent billions of dollars without deploying a single prototype to the ISS?
Do you see what will happen if NASA abandons the shuttle fleet at this point? That money will go somewhere else. Congress will not sit on their hands and the Space Program's budget would surely feel their bad-touch. This is not your Civilization: III game. Grounding the shuttles would not hurry production of the replacement hypersonic SSTO mega-ram-jet. (note: It might spur the design process but development would still be decades away). ISS and shuttle clearly aren't perfect, but they are still impressive solutions for reusable launch vehicles and frontier bases.
Registered: Sep 2000
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posted
Damn, and instead they had to go and let that Commander from IASA use it to try out some crazy sligshot-manoeuvre experiment. Did they ever find out what happened to him? Probably ended up in lots of little pieces. . .
posted
Oh, he showed back up eventually. Or priorly. Or both.
I never did figure out how he intended to get home in the first place...
-------------------- "This is why you people think I'm so unknowable. You don't listen!" - God, "God, the Devil and Bob"
Registered: Mar 1999
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Just as you aren't supposed to notice Congress raising the military budget, and giving themselves a raise while slashing NASA's budget.
It's all a matter of "suspension of disbelief".
-------------------- Justice inclines her scales so that wisdom comes at the price of suffering. -Aeschylus, Agamemnon
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-------------------- Justice inclines her scales so that wisdom comes at the price of suffering. -Aeschylus, Agamemnon
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posted
I'm not saying that NASA should scrap the shuttle in favor of building a next-generation ship, but rather that it seems possible that the shuttle deserves to be scrapped on its own merits, regardless of what (if anything) might replace it, or when.
(The Encyclopedia Astronautica is such an awesome site.)
(I am not necessarily in the "manned spaceflight is a waste of resources" camp ((and when it comes to ideas that make me happy, manned spaceflight is way, way up there)), but I do think we need some serious reasons to engage in it, and I'm not sure that the space shuttle supplies any, especially under the new requirements. Though here I will betray my very limited knowledge and ask: to what extent will the need to dock with the station limit shuttle missions? I mean, obviously shuttles operate with a healthy fuel reserve already, and presumably the fuel required to get to the station won't be taken from this reserve, but rather from the amount dedicated to regular operations. Now my first guess would be that the amount of fuel required to match the station's orbit and dock with it is not insubstantial, causing all sorts of missions, such as a Hubble repair mission, to be out of the question. But it is quite possible that most shuttle missions, even most interesting shuttle missions, don't require enough fuel to be rendered unworkable by the new rules. Nevertheless, it seems clear that the shuttles are well along the path of diminishing returns, and their capabilities are only going to get more limited from now on.)
Registered: Mar 1999
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posted
As a means of deploying billion-dollar satelites into stable orbits, the shuttle cant be beat, but I agree that the shuttle's role is becoming more limited all the time.
I dont think the shuttle should be replaced with a radical new design all at once, but rather that a series of new designs should be built using what works well on the shuttle and incorperating innovations from there.
How difficult (for example) would it be to build a slightly larger shuttle that could serve as a command post for a moon mission? I would probably be possible to convert the shuttle's cargo bay for that purpose (or even as an additional oxygen and fuel reserve for extended missions.)
The idea of keping the shuttle design exactly as it's been for the past twenty years is just...stagnant.
-------------------- Justice inclines her scales so that wisdom comes at the price of suffering. -Aeschylus, Agamemnon
Registered: Aug 2002
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