- The Washington Times - Tuesday, December 28, 2004

ASSOCIATED PRESS

NASA takes a major step toward returning astronauts to space when engineers this week ship an improved rocket fuel tank that has been refitted to avoid the falling debris that caused the destruction of Space Shuttle Columbia and the death of seven astronauts.

Officials said the redesigned fuel tank, a massive vessel that supplies propellant for the launch of the shuttle, will start a barge trip on Friday from a Louisiana assembly plant to the launch site on Florida’s east coast.

Sandy Coleman, NASA’s external tank project manager, said improvement of the fuel tank “gives us confidence that problems like what happened on Columbia will not happen again.

“This is the safest, most reliable tank NASA has ever produced,” Miss Coleman said.

The changes in the external tank add less than 150 pounds in weight. The total cost of the new tank, including tests and redesign, is still being calculated, but it is expected to be more than the $40 million spent for the old-style tank.

Miss Coleman said the tank was expected to start on a barge trip Friday from the Michoud Assembly Facility near New Orleans to the Kennedy Space Center. The barge journey, which crosses the Gulf of Mexico, rounds the tip of Florida and then up the east coast, takes five to six days.

NASA plans a May or June launch of Space Shuttle Discovery. The shuttle fleet has been grounded since the Feb. 1, 2003, Columbia accident as NASA scrambled to make changes in hardware, procedures and personnel to comply with recommendations from the Columbia Accident Investigation Board.

Fixing the external tank was a key part of NASA’s recovery effort, officials said.

The tank holds the liquid hydrogen and oxygen that are the propellants for the shuttle’s main rocket engines during launch. The supercooled chemicals cause the formation of ice on the outside of the tank as the shuttle is prepared for launch.

Insulation, applied as a foam, reduces the amount of ice. But investigators think it was chunks of foam insulation that peeled off the external tank during launch and led to the destruction of Columbia. The debris, moving at a high relative speed, ripped a hole in the left wing of the shuttle. As the spacecraft re-entered the Earth’s atmosphere, superheated gas penetrated the wing through the hole and melted metal struts. The craft shattered, showering east Texas with flaming debris. Seven astronauts were killed.

The Columbia Accident Investigation Board conducted tests to prove that chunks of the lightweight foam insulation could cause the damage that was fatal to Columbia.

To correct the problem, engineers from NASA and Lockheed Martin Space Systems Co., manufacturer of the fuel tanks, conducted extensive tests to find out why the foam insulation broke loose during launch.

This led to several changes, including new ways of applying the foam insulation, the addition of heaters at key points to prevent the formation of ice before launch, and adding cameras that can monitor the outside of the tank during launch.

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