Answers to Common Questions on Columbia
Feb. 6, 2003 -- The Columbia first flew in April of 1981 with a crew of two: John Young and Robert Crippen.
Three more test flights followed before the shuttle system was considered "operational." After the fourth flight, the manufacturer, Rockwell, began publishing advertisements saying: "When a spaceship lands on earth, it comes from Rockwell," emphasizing the fact that here was a spaceship that could land like an airplane and fly again another day.
The shuttle system is amazingly powerful and capable. When you watch it launch, you're seeing 4.5 million pounds of machinery leaving the ground under control on a collective rocket thrust of about 7- to - 7.5 million pounds, depending on payloads. Its design is a geometry that makes it a launch vehicle, orbiting space station and airplane/glider in one package. It is extremely capable, but it has definite limitation based on the state of current technology, physical law and budgets.
Here are the answers to some questions frequently asked in the wake of the Columbia disaster:
Q: Could Columbia have been aborted to a safe landing during powered flight to orbit?
A: Yes. The spaceship can be separated from its fuel tank after the booster rockets burn out. With the speed imparted to the point where the decision is made to abort, it can be directed back to the Kennedy Space Center or it can be sent for a gliding landing in Africa or Spain. If the problem is discovered late in the climb to orbit (for instance, loss of one or more engines) it can be aborted to orbit.
Q: Why didn't they go to the International Space Station and get off Columbia?
A: They didn't know there was a problem, so no rescue effort of any kind was considered necessary. But in more practical terms it would have been impossible for Columbia to get to the space station. The two vehicles (shuttle and station) were in very different orbits and there was insufficient fuel for Columbia to change its track. Besides, Columbia was never designed or equipped to dock with the space station. Columbia was restricted to orbits near the earth's equator where it could be used as a minor space station for two-week science missions. Such a rescue would be possible for the three remaining orbiters provided they had enough fuel to reach the station. Shuttles Discovery, Atlantis and Endeavour are all equipped to dock with the station in the course of their assignments.
Q: Could some other kind of rescue have been attempted for Columbia's crew?:
A: Problematic. We've all seen the miracles worked during the Apollo 13 mission, in which bits and pieces are combined to keep the crew alive long enough to reenter Earth's atmosphere. But in this case, it's hard to see how it would be done. Columbia had no airlock, so transfer of people from one shuttle to another would be impractical. The right kind of equipment was simply not available.
The other consideration is whether another shuttle could have reached them in time. Columbia was at the end of a 16-day mission and had only a few days of reserves on board. It normally takes about a month from the time a shuttle gets on the pad until it can be launched. Experts say it could be done in a week if all tests and safety precautions were circumvented. But once a rescue craft got there, how would you get them off? We've never flown two shuttles at the same time, much less in close formation.
But the bottom line remains as before: they apparently didn't know they needed a rescue.
Q: Did a piece of foam insulation cause all this?
A: Don't know. The piece that struck Columbia weighed less than 3 pounds, but there are other considerations: Did it strike the leading edge of the wing at a particularly vulnerable spot? What if it contained ice? Remember, the piece came off when the shuttle was climbing at speeds more than twice the speed of sound, between 1,500 and 1,900 miles an hour. That changes things. But it's hard to connect the symptoms observed before the shuttle broke up (random heating, rapid steering adjustments) with the wing strike. That is torturing the investigators.
Q: Why are they now looking for debris in California?
A: The theory is that pieces farther west will be from the part of the fuselage where the trouble started. Seeing how the pieces broke up and exactly what they are could put a new light on the situation.
Q: Can this be cleared up quickly?
A: Probably not. These things are always more complicated than they appear to be at the outset and require the talents and agreement of hundreds of highly skilled people.
Q: Since the shuttles may be grounded until the problem is found and fixed, how does this effect the International Space Station?
A: For the time being, it doesn't effect it very much at all. Food, clothing, water, equipment and even mail from home is being supplied to the three persons aboard the station through deliveries on robotic space ships launched from Russia. As they stand right now, the crew is good through mid to late summer.
A three-seat Russian Soyuz spacecraft is always docked to the tail of the station. It is kept turned on and the hatch is always open for a quick escape if things go badly. The Soyuz are replaced every six months to keep their fuel systems fresh. A three-member crew flies up with the new one and brings the old one home. Theoretically, the crew now on board the station return to earth on the old one while the crew on the new one would take their place.
The larger problem is that the other three shuttles are also the delivery trucks for equipment and materials used to expand the huge station. That will stop for the time being, leaving the station as it now is. If the investigation lasts a really long time, managers will have to consider putting the station on automatic control and closing it up for the duration. That wouldn't be good for it, but it can be done.
It won't be good politically, either. The U.S, Canada, Russia, European consortium and Japan are all invested in the station. Most of the partners are still waiting to have their equipment and their people delivered to the station to begin scientific research. And that's another story: briefly, the station's crew size must grow for the modules provided by Japan and the Europeans to be installed and begin operation. That will require more than the three crewmen now aboard the station and the crew size cannot grow until there is something with more seats than a Soyuz to serve as a "lifeboat". So far, that's a plan that has waited in the budgetary wings.