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Columbia disintegrates during re-entry into earth's atmosphere
By Alexis Dyer
National/World Co-Editor
FILE PHOTO
The Columbia, which was the oldest shuttle in the NASA fleet, on one of its many missions before the disaster
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On Feb. 1 the space shuttle Columbia disintegrated over Texas during its final descent, less than 15 minutes before it was scheduled to land at Cape Canaveral. There were seven astronauts on board, including Ilan Ramon, the first Israeli to travel in space.
At approximately 9 a.m. Eastern time, NASA controllers monitoring the progress of the Columbia noticed a problem with the temperature sensors in the left wing of the craft. The wing had been struck by a piece of insulating foam during its Jan. 16 takeoff. Shortly after this discovery readings from the sensors were cut off altogether. “It’s as though someone just cut the wire,” said Ron Dittemore, shuttle program manager, according to The New York Times.
Tire pressure readings for the landing gear stopped functioning as well, and the shuttle began to tilt slightly. There were also indications of “excessive structural heating,” according to The New York Times. Dittmore told The New York Times that the abnormal tilting could be indicative of rough or missing tiles on the underside of the craft.
NASA engineers also suspect that because the landing gear readings malfunctioned sequentially instead of all at once, the problem most likely was with the monitoring system, not the tire itself.
After acknowledging warnings about problems with the tire pressure gauge, the astronauts lost contact with ground control. The unidentified astronaut communicating with the ground was cut off in mid-sentence after stating “Roger,” according to The New York Times.
The shuttle’s distress could also be viewed and heard from the ground. Many residents of Northern Texas reported seeing flames and hearing a loud noise on Saturday morning as the space shuttle disintegrated overhead. Residents of Louisiana also saw and heard the blast and flooded local police stations with phone calls. State police Sgt. Steve Robinson of Bossier City, LA told The New York Times, “One [caller] said he saw a place breaking up over Shreveport. One said he saw a big ball of fire. One guy said his house had a blast that shook his house.
Since the accident, investigators have been collecting pieces of debris from the shuttle. Most of the material was recovered in Eastern Texas, including a piece of landing gear, a cockpit seat and several orbs still containing fuel.
The search was also extended to areas of California and Arizona after data and an amateur videotape indicated that the Columbia most likely lost debris while traveling over these states before ultimately coming entirely apart over Texas.
The remains of the astronauts themselves were also partially recovered. Three children in Plainview, Texas found a charred leg. Their mother reported finding the upper body of one astronaut on her neighbor’s property a mile away. In addition, a man in Hemphill, Tex. reported finding a torso, while searchers in San Augustine County found a heart, leg and fingers.
Since the disaster, NASA has been defending itself against accusations that negligence caused the Columbia disaster. Some experts believe that the fragile tiles, which act as a heat shield, were the cause of the problem, according to The Associated Press. NASA, they say, has known since the early s that foam insulation on the fuel tank of the space shuttle sometimes tears off and damages the tiles during takeoff.
Others criticize NASA for not halting the mission after a chunk of insulation hit the left wing of the Columbia after liftoff. NASA engineers were not aware of this occurrence until the second day of the mission, when they viewed videotape of the launch.
The engineers, according to The Associated Press, called the hit “inconsequential.”
In response to the criticism over the safety of the tiles, NASA scientists stated that extensive measures have been taken over the years to improve the durability of the tiles, but that it was impossible to foresee every danger because flight conditions cannot be accurately simulated in the lab.
George Diller, spokesperson for NASA, told The New York Times that the tiles are the most durable and least labor intensive of all the heat-shield options. “I think the tiles have gotten a bum rap,” he said.
Officials also dismissed accusations that something could have been done to prevent the accident after they became aware of potential damage to the left wing sustained during liftoff.
They said first, according to The Associated Press that the mission was not aborted immediately because they did not realize the problem until the next day, when the Columbia was already in orbit. They also said that the crew had no tools to fix the damage and that the crew could have done further damage to the tiles by climbing on them. The suggestion that the shuttle could have docked with the International Space Station was dismissed because the shuttle was not carrying enough fuel to get there.
Another shuttle, the Atlantis, was scheduled for a mission in March and many believed that it could have been sent up to rendezvous with the Columbia and fix the problem. However, it takes weeks for a shuttle to be cleared, and the Columbia would have run out of fuel before the Atlantis was able to launch.
Finally, some argued that the Columbia should have taken another descent path that would have reduced stress on the damaged left wing.
Dittemore refuted this, saying, according to The New York Times, “I’m not aware of any other scenarios, any other techniques that would have allowed me to favor one wing over the other.”
Regardless of whether or not the disaster could have been prevented, the accident still raised questions concerning the future of the space program.
President Bush has already expressed support for continuing the program, according to The New York Times.
The amount of time that will pass before the next mission, however, is unclear. After the Challenger disaster of 1986 it was three years before the next shuttle launch.
This is a concern mainly because several flights were scheduled throughout the year in order to work on the International Space Station. If these flights are grounded completion will be delayed indefinitely and the three astronauts currently in the facility will have to be returned home via rescue capsule or a Russian Soyuz spacecraft dispatched in emergencies.
A memorial service for the seven astronauts was held on Tuesday. Several people made remarks, including President Bush, who mentioned each of the seven individually.
He also quoted Lt. Col. Michael P. Anderson, who told his minister before leaving, according to The New York Times, “If this thing doesn’t come out right, don’t worry about me; I’m just going higher.”
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