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Wing Seals Blamed in Columbia's Demise
MoonFacedAssassin writes "MSNBC has this article stating that a 'seal from Columbia's left wing was apparently the mystery object that floated away in orbit, and it was almost certainly struck by something - like a chunk of foam - before it came off, accident investigators said Tuesday.' The article also quoted Navy Rear Admiral Stephen Turcotte, a CAIB member, as having a confidence level 'up there near the 70s and 80s percent' about the T-seal."
New Scientist also has the latest.
The foam is quite a bit more rigid than nerf ball material :) It's more like hard foam some bicycle helmets and knee pads have in them... I used to intern at the place that makes the external tanks and had a chunk of the foam at my desk.
"People that quote themselves in their signatures bother me" - athakur999
Communications. If the shuttle is on top the tank would block transmissions to and from the shuttle.
If you don't want to repeat the past, stop living in it.
No. The ISS is in LEO (400km altitude; neither shuttle nor Soyuz can get much higher), it's a question of orbital inclination, which takes as much fuel to change as it took to get the spacecraft in orbit in the first place. (Well, roughly; I had calculated that 120-160tonnes were needed, the external tank at launch holds 2000, and the Soyuz less than1...)
Not even close, I'm afraid.
Not for a return to Earth (the seats are form-fitting and the landing quite hard), otherwise possibly, but the more people aboard, the more fuel is required to get anywhere...
No. And they don't use the same docking ports on the ISS either.
No. The best bet, provided that the danger were known at the beginning of Columbia's mission, was to conserve power so as to last maybe an extra week or two in orbit, and rush Atlantis through launch preparations, bypassing a number of safety regulations to have it ready in less than a month. And only because it happend to be already sitting on the pad.
Sorry to sound rude like that, but I hear this kind of misconceptions so often...
It is said to be in the cards. Not that it would help (the ISS can't hold that many people for long), but no mission was planned elsewhere except for the last Hubble repair before its planned end of life, and all interesting places to go are out of the shuttle's reach anyway.
Shoulda checked before posting, although that was my recollection.
The shuttle turns over so the crew can see the horizon and have a visual frame of reference if they needed to take over manual control without instrumentation in case of an abort. Sitting on top of the external tank they wouldn't know where they were.
If you don't want to repeat the past, stop living in it.
"As far as I recall, the shuttle does not have leading egde flaps. Thus it shouldn't be a reason for a 'split' design like the article describes, a solid leading edge panel made of reinforced carbon should be both possible and perhapes even less expensive"
You sound uninformed and are speculating without even attempting to research the subject. The RCC (Reinforced Carbon-Carbon) panels have gaps between them for a reason. The panels are mounted on floating joints to reduce the loads placed on them due to wing deflections. This also helps reduce the effects of mismatched thermal expansion coefficients between the aluminum wing structure and the carbon composite material they are made of. You can read more about the RCC panels and their attachment to the wing structure at:
http://science.ksc.nasa.gov/shuttle/technology/sts -newsref/sts_sys.html#sts-rcc
Your comment that a design that causes a breach to the interior structure in case of failure is a flawed one doesn't make too much sense either. The TPS (Thermal Protection System) design is there specifically to protect the orbiter structures that cannot withstand the heat of reentry. Therefore, by design, if the TPS was not there, the structure would be breached. You should look for flaws in the design based on a lack of anticipation of possible external damage modes and not in that it was a very critical system whose loss results in an overall failure of the orbiter.
Now I see what you meant. But there is something you missed: the orbits which can be reached by the shuttle are not at all the same as those orbits which it can reach after being launched into a different orbit.
Imagine you are making a trip with a car, and a bike inside the car. Assume that no gas stations are available, and that you want to consume the car's whole tank and then ride around with the bike. You can go a few hundred km with the car, say either from Paris to Geneva or from Paris to Brussels. But once you have arrived in Brussels, you can't change your mind and use the bike to get back to Geneva.
It's the same with the shuttle: it can go to the ISS, but you have to decide on it before launch. Afterwards, your fuel is gone, it's too late.
So the problem with your idea is that you would have to park and maintain boosters or fuel tanks at every possible orbit that the shuttle might want to reach, which makes a lot of them.
A shuttle can launch 20-30tonnes of payload to low Earth orbit depending on the orbital inclination (the higher the more difficult except below the latitude of Cape Canaveral, which is impossible when launching from there). Last winter's event would have required 120-160tonnes of fuel to get to the ISS--with a moderate-efficiency engine such as the OMS or a kerosene-oxygen one; solid motors are not as good. But you could station a full tank every few degrees and use several of them, each getting you to the next one.
Expensive but not impossible--that could be interesting once we develop a space-based infrastructure, with materials and fuel coming from nearby asteroids or maybe the Moon or even Mars.
And, of course, this doesn't solve the problem of keeping everybody alive more than a few days at the ISS.