CNN
Posted on 02/01/2003 10:18:41 AM PST by Timesink
Seven astronauts, including the first Israeli in space, were lost Saturday when the space shuttle Columbia broke apart in the skies of Texas. The incident occurred at an altitude of some 200,000 feet, shortly after reentry and 15 minutes before Columbia had been scheduled to land at Cape Canaveral. TIME science correspondent Jeffrey Kluger explains some of the possible causes and consequences of the accident:
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TIME.com: What are the possible scenarios that could have caused this disastrous accident on the shuttle's reentry into the Earth's atmosphere?
Jeffrey Kluger: There are three possible scenarios that explain this event. The first, which I believe is the likeliest explanation, would be an aerodynamic structural breakup of the shuttle caused by it rolling at the wrong angle. Remember, after reentry, the shuttle is descending without power, which means astronauts at the controls can't compensate for a loss of attitude by using the engines, they can only do so using the flaps. And that's extremely hard. Astronauts describe piloting the shuttle on reentry as like trying to fly a brick with wings. It's very difficult to operate, and even more so to correct any problems.
A second explanation might be a loss of tiles leading to a burn-through. (The shuttle is covered with heat-resistant tiles to protect the craft and those inside it from burning up in the scorching temperatures caused by the friction of reentry.) But I think that explanation is unlikely, because the tile-loss would have had to have been quite substantial for that to become possible. You'll hear a lot in the next few days about things falling off the shuttle during liftoff. But it often happens that they lose a few tiles, and I'd be surprised if it happened on a scale that could make an accident of this type possible.
The last option is some kind of engine failure leading to fuel ignition. Although the main tanks are mostly empty, there should still be fuel left in the maneuvering tanks. But probably not enough for an explosion that could have caused this breakup.
And just in case anybody was wondering, you can almost certainly rule out terrorism as a cause. This incident occurred well above the range of shoulder-fired missiles. And it would probably be easier to sneak a bomb onto Air Force One than to get one onto the shuttle.
TIME.com: So is reentry the Achilles heel of the shuttle program?
JK: No, the Achilles heel has always been liftoff, and the dangers posed by massive fuel load involved. Reentry has, of course, always been a difficult part of the space program. But this is, in fact, our first fatal accident on reentry. Apollo 13 is remembered as our most difficult ever reentry, but the ship and crew survived. The Soviets lost a crew on reentry in 1970 after an oxygen leak that caused the cosmonauts to suffocate on the way down. Reentry is a very difficult process, but the Russians mastered it in 1961 and we did the same a few years later.
TIME.com: Are shuttle crews trained to respond to the scenarios you've described?
JK: Yes, they're trained to deal with loss of attitude on reentry, and a range of other emergencies. But astronauts are not trained to deal with situations that result in certain death, because that would be a bit like training for what you might do if your car went over a cliff — in some situations there simply isn't anything you can do. One irony, though, is that NASA hadn't trained astronauts to deal with the sort of quadruple failure that occurred in Apollo 13, because they assumed that such a scenario would result in certain death. But the astronauts survived.
TIME.com: What are the immediate implications for the space program of Saturday's disaster?
JK: Following the precedent of the Challenger disaster in 1996, it's unlikely that NASA will undertake any further shuttle missions or any other manned space flights for the next two years. One immediate problem, though, is the International Space Station, which currently has a crew of three on board. They might consider one further flight to bring that crew home — the other option would be for them to return aboard a Russian Soyuz craft, which isn't the most comfortable or the safest ride. Beyond that, however, the space station is likely to be left unoccupied for a long time. NASA won't want to use the shuttle again until it can establish the cause of today's accident, and fix it. Now that we've lost two shuttles out of a fleet of five, it's even conceivable that the shuttle won't fly again. The shuttle was built as a space truck, and then the International Space Station was built to give it something to do. Both programs are likely to suffer as a result of this disaster.
The Fox News article is:
http://www.foxnews.com/story/0,2933,77253,00.html
And it is posted under www.freerepublic under breaking news as "Space Shuttle Disintegrates over Texas".
I will post that URL in a moment.
But during liftoff, on January 16th, the Space Shuttle's wing was damaged.
Here is the paragraph that is key to explaining this disaster (in my opinion), and shows what junk TIME.COM is publishing:
Shortly after Columbia lifted off Jan. 16, a piece of insulating foam on its external fuel tank came off and was believed to have hit the left wing of the shuttle. Leroy Cain, the lead flight director in Mission Control, assured reporters Friday that engineers had concluded that any damage to the wing was considered minor and posed no safety hazard.
Basically, the wing was damaged on liftoff, and when the re-entry time came, the wing was put into "Maximum" stress by the initial re-entry -- 200,000 ft up at 12,000 mph.
So even minor damage at this speed can be disastrous.
Time reporters, as usual, are problably on dope.
If you read the Fox article, the key fact is there to be dug out.
This was EXACTLY the weakness I pointed to in my article, posted earlier, on the aerospace plane.
And it is posted under www.freerepublic under breaking news as "Space Shuttle Disintegrates over Texas".I will post that URL in a moment.
Here is the URL to the FreeRepublic Thread on the Fox News story (which is sound reporting), as opposed to the "trash" from TIME.COM, which just reported a $100 billion loss and Ted Turner stepping down as Vice Chairman.
URL:
http://www.freerepublic.com/focus/news/833975/posts
"Space Shuttle Disintegrates over Texas"
Following the precedent of the Challenger disaster in 1996, it's unlikely that NASA will undertake any further shuttle missions or any other manned space flights for the next two years. One immediate problem, though, is the International Space Station, which currently has a crew of three on board. They might consider one further flight to bring that crew home — the other option would be for them to return aboard a Russian Soyuz craft, which isn't the most comfortable or the safest ride. Beyond that, however, the space station is likely to be left unoccupied for a long time. NASA won't want to use the shuttle again until it can establish the cause of today's accident, and fix it. Now that we've lost two shuttles out of a fleet of five, it's even conceivable that the shuttle won't fly again.Only if pansies are running the show! Not only do we need to get back there post haste, we need to build a couple more shuttles...
Yeah. Tire blows causing structural, electronics and hydraulics damage. No control of aero surfaces needed for re-entry manoevers.
Uh, huh. Very telling.
Time for a Vision Thing. Apparently we have two years to come up with a reason to keep doing this, this way.
I would have to see what this 'foam' is that hit the wing. If it is just a fiberglass puff foam, I do not see how it cold have damaged the leading edge. Even if it is a hard woven glass skin with foam underneath, I do not see how it could have damaged the wing, doesnt make sense.
BUT, since this is a material that has to survive liftoff heat and speed of wind, I imagine it had a hard shell, almost ceramic outside.
Anyone here got a link on just what that material is on the center tank?
I don't believe that will be the case. The Russians will continue to fly to the space station.
I can say this; the Ceramic tiles are not like the ceramics you find in a local store. I can grab the material and crush it in my hand. Feels almost like foam. I have a piece of it here in my office and it has dents from my fingers.
Yeah, it was a sonic boom. Even a broken-apart shuttle is going to give a boom once it breaks the sound barrier ... or perhaps many booms?
Based on what I've seen, it appears that there was a problem with the re-entry before the shuttle broke apart -- this is why I find the word "explosion" so annoying in this context. One of the video clips clearly shows the shuttle coming down sideways before the debris contrails start to appear.
There are more than one. They recovered at least one after Challenger as I recall. Also don't forget that there is a constant stream of telemetry downlinked to mission control at JSC. There is very little doubt in my mind that the root cause(s) of this mishap will be identified.
While the shuttle design is based on 30 year old technology, I highly doubt TPTB would simply trash the entire shuttle program. This would set the US back significantly and wouldn't be a logical move. Even a two year lay off wouldn't be proper decision to make. The space station needs to be manned and without the use of the space shuttles, to keep up the rountine maintenance, it would fall into disrepair and be a huge waste of money.
The next generation of space vehicles need to be moved from the planning stages and into full production, immediately.
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