Dinged by Katrina, Endeavour fuel tank has scars

[April 28, 2011]  CAPE CANAVERAL, Fla. (AP) -- The fuel tank that will help propel the space shuttle Endeavour into orbit is already battle-scarred from some rough shaking thanks to Hurricane Katrina.

The 10-year-old tank was in a building in New Orleans when Hurricane Katrina hit in 2005. The building's roof partially collapsed, causing more than 100 nicks in foam and one piece of dented metal.

The pumpkin-colored tank now has 103 patches.

It also has a special plaque to remind people that this tank went "through the eye of a hurricane," said Jeff Pilet, chief engineer for tank maker Lockheed Martin.

"It was a very trying time, but here we are celebrating," Pilet said at Kennedy Space Center on Wednesday.

Lockheed Martin and NASA spent eight months examining and repairing the massive external tank, making it ready for Friday's launch. It will be the oldest fuel tank to launch. The tank had been finished and in line for launch when the 2003 Columbia accident occurred. Foam shed from the fuel tank during liftoff and damaged Columbia's left wing. That led to a redesign of the fuel tank's insulation, delaying tank No. 122 by a few years.

Then Katrina hit, peeling a bit off the roof of the giant building that sheltered the fuel tank. Luckily, the debris from the roof only hit the half of the tank that is away from the shuttle and "less risky," Pilet said. He also said much of the tank was shielded because of scaffolding.

"The damage really wasn't that bad," Pilet said.

Still, engineers repaired the nicks in the foam and a dented metal piece that connects the two inner tanks. The biggest gouge in foam was 15 inches by 20 inches. Pilet said he has "high confidence with the repairs we've applied" and NASA's chief fuel tank engineer Ken Welzyn agreed.

Pilet said some foam could still fall from the tank during liftoff, mostly because it is an older tank retrofitted from the earlier design. But the foam that may fall would be so late in the launch that it wouldn't cause any damage to the shuttle, he said.

The tank -- 154 feet tall and 27 feet in diameter -- is the only major part of the shuttle system that doesn't get reused, falling into the Indian Ocean after the launch. It holds more than half a million gallons of supercooled liquid oxygen and hydrogen, kept cold by more than 2 tons of insulating foam. When filled, the tank weighs nearly 1.7 million pounds.

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Online:

NASA: http://www.nasa.gov/shuttle/

[Associated Press; By SETH BORENSTEIN]

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