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.
Where do the news networks find such nitwits. The US successfully tested a Mercury capsule in 1961 with a chimpanzee aboard prior to Gagarin's flight.
At first I thought you were talking about Fidel.
Then I thought you were talking about your Feline.
Never mind.
So was the original plan to build five vehicles of which only four would be spaceworthy?
Oh!
At first I thought you were talking about Fidel.
Then I thought you were talking about your Feline.
Never mind.
I appreciate your successful attempt at humor on a rough day. I have nerve damage in my left arm and my brain might be worth preserving upon my death for its anomolous properties needing to be studied. Cats and Castro, what a hoot!
I looked up this guy's credentials, he is not an engineer nor a pilot. He is a keyboard jockey.
As a glider pilot, I can tell you that using flaps is the fastest way to restore control, engines are too slow to react and only point thrust in one direction. This guy need to go back to writing about gardening.
As long as any re-entry vehicle is surrounded by hot plasma during re-entry, no real time data can get through.
Lockheed Plans Redesign of Venture Star
By Jonathan Lipman
Special to space.com
posted: 06:51 am ET
30 September 1999
WASHINGTON (States News Service) – Lockheed-Martin will use an external payload bay on its Venture Star vehicle instead of an internal one like its prototype the X-33, said Lockheed Vice President Jerry Rising at a congressional hearing.
Lockheed learned from the X-33 that the VentureStar will be more efficient if it carries its payload bay in an external canister, Rising said, rather than inside the vehicle like the X-33. The new configuration is already undergoing wind-tunnel testing, he added, and will be unveiled within a couple of weeks.
By removing the space for a payload bay inside the craft, Lockheed can package the light-weight fuel tanks and other internal systems more efficiently, said Lockheed Martin executive Anthony Jacob, giving the VentureStar greater lift capability.
The canister, which will look like a fat pencil riding on top of the wedge-shaped vehicle, will be 53 feet long and 15 feet in diameter, and will have the same payload space as the previous design, somewhat less than the space shuttle.
"It makes it safer, really" for any possible crew, Rising said. The canister would ride on the lee side during re-entry, so that the entire ship would act as a heat-shield in the event of a problem.
"You have to accept what I call ‘morphing’ of the operational design to take advantage of what you learned from the [X-33]," Payton said. For NASA’s proposed Crew Return Vehicle, which the VentureStar would theoretically lift to orbit with the ISS crew, "it’s an easier design as far as simple, mechanical integration goes," Payton said.
The canister would also allow more flexibility for payloads, since it could be changed for larger or odd-shaped payloads, Rising said.
Not at all. Werner Von Braun was still alive when the shuttle was on the drawing board. He viewed shuttle as an interim step to an aggressive space program. The anemic funding to NASA by LBJ, Nixon, and Carter resulted in the program that we now discuss. There was a test article or several, one of which was flight tested. The shuttle fleet has always been limited in terms of flight rate by processing and available launch facilities. There may be a day when launches will not be constrained by either but I think I am getting to be too old to see the final outcome, much to my great chagrin. Max Faget, a marvelous madman if there ever was one, had some great ideas about how to proceed with establishing a more permanent presence in space. He was ignored and put out to pasture as most old people are in the course of progress.
You must be ingesting copious amounts of genetically altered foodstuffs and ensconced in tin foil. Your statement is bald of truth as it applies to the return of a shuttle for landing.
A character in the book poured an amount of acid onto the ceramic tiles of a couple soviet shuttles. This supposedly roughened the tiles, allowing aerodynamic forces to compromise the shielding.
That being said I do not believe this was a terrorist attack. I do appreciate alternative theories on what could have happened, I just do not immediately associate them with terrorist activity. I believe most things that could have happen, most likely fall into the "stupid $hit that gets people killed but didn't mean it" category
Yes that particular Mercury flight was suborbital, but it did test the reentry system and heat shields. We were in no way behind the Soviet Union in developing our space technology in 1961. It's just that the Soviets were willing to take greater risks with their personnel. The statement I quote said that our reentry systems were not perfected until several years later which is not true. Both Allan Sheppard and Gus Grissom successfully reentered the atmosphere in 1961, and the four manned orbital Mercury flights also successfully reentered the atmosphere.
Due to heating during re-entry into the atmosphere, any re-entry vehicle is surrounded by plasma, which, oversimplified, is superheated gas to the point where it is ionized. The plasma, which is electrically conductive, prevents any RF traffic between the RV and the ground. No voice communication, no telemetry. When the velocity of the RV is reduced to the point where friction heating no longer produces plasma, RF communication can be re-established. This has been noted since the Mercury program. Not tinfoil, simply physics. Now if the shuttle was past the re-entry regime where there is plasma just before the failure events, then I stand corrected. If not, you are as technically illiterate as the rest of the media loons including Dan Blather.
Surely you jest. Ask John Glenn if his orbit around the Earth was real.
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