NASA has found cracks in the insulating foam on a space shuttle fuel tank and is investigating whether they are related to the debris-shedding problem that doomed Columbia and recurred on the last shuttle mission, managers said on Tuesday.
"It would be premature to say that the cracks played a factor in that, but they might have," said John Chapman, who oversees the shuttle external tank program at NASA's Marshall Space Flight Center in Huntsville, Alabama.
Technicians found nine hairline cracks in the insulation on a fuel tank that was originally earmarked for the Discovery mission launched July 26. It was twice filled with cryogenic fuels for tests before being replaced with another tank, for unrelated technical reasons, before Discovery launched, reports Reuters.
According to Houston Chronicle, the latest findings on a fuel tank once assigned to the Discovery flight, but subsequently shipped back to Michoud from NASA's Kennedy Space Center in Florida, add a new wrinkle.
The tank was twice filled with supercold liquid hydrogen and oxygen propellants during launchpad testing last spring, operations that cause the 154-foot-tall fuel tank to expand and contract, possibly enough to contribute to the foam cracking, said John Chapman, NASA's fuel tank project manager.
Engineers are assessing three techniques to address the foam loss on the PAL ramp, a foam structure on the tank to deflect airflow away from external plumbing and electrical lines.
They include applying the foam with a new manual spraying technique, using a robotic sprayer and removing the ramp altogether, Hale said. source