Thursday, February 20, 2003
Officials test fuel tanks to find clues in wake of shuttle disaster
NEWS-JOURNAL WIRE REPORT
HOUSTON — After more than two weeks of evaluating scores of theories about what led to the disintegration of the shuttle Columbia, investigators are concentrating again on their early idea that a piece of insulation or other flying debris from the shuttle´s 15-story external fuel tank damaged a wing at liftoff, dooming the craft.
In the investigation´s first days, NASA said it was focusing on the insulation, which is applied as foam but dries rigid, then all but ruled it out. Now, with a new panel independent from NASA leading the investi gation, it is back in the spotlight, along with ice that might have formed on it and a protective silicone-based layer that lies beneath it.
The ice and the silicone-based material are considered potentially more dangerous.
At the Michoud Assembly Facility, the NASA plant in New Orleans where the tanks are made, investigators have begun testing another 15-story fuel tanks to see if any of its materials were likely culprits, a work er at the plant said Wednesday.
The tests are taking place in the 20-story Vehicle Assembly Building, where the 154-foot external tanks are built vertically and sprayed with foam by computer-controlled guns. The tank had already been sprayed with foam, the worker said, adding that he did not know exactly what experiments were being performed.
The worker, who spoke on the condition that he not be named, said NASA investigators were also looking at whether air bubbles or ice could have formed beneath the silicone-based material, an insulation known as super-light-weight ablator that is used on various parts of the tank. The worker said that Lockheed Martin, which builds the $43 million tanks for NASA, had told workers to talk to no journalists.
In related news, NASA said the shuttle´s nose landing gear was found in the east Texas woods Wednesday.
Johnson Space Center spokeswoman Eileen Hawley said it is unclear whether the nose gear could shed any light on what destroyed the shuttle.
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