- The Washington Times - Friday, June 6, 2003

SAN ANTONIO — Foam fired at high speed caused a 3-inch crack in a space shuttle wing panel yesterday, offering investigators perhaps the best evidence yet for the likely cause of the Space Shuttle Columbia’s breakup.

Investigators looking into Columbia’s disintegration helped bolster their argument that a ferocious impact from foam insulation could have damaged the shuttle and contributed to the Feb. 1 disintegration during re-entry that killed all seven astronauts.

“This is the first evidence we have that a piece of foam that approximates what we had in the accident can, in fact, crack and damage a piece of reinforced carbon panel,” said Scott Hubbard, a member of the Columbia Accident Investigation Board.

Investigators may do one more test on another carbon panel by the end of the month.

The $1 million foam-impact test at Southwest Research Institute took just a second.

Investigators shot a 1.67-pound piece of foam from a nitrogen-powered gun at an estimated 528 mph into a 15-foot-long replica of a section of Columbia’s left wing. They took aim at a single carbon panel from the Space Shuttle Discovery, but the impact produced damage beyond the impact point.

In addition to the 3-inch crack left by the foam impact, Mr. Hubbard said, a close inspection of the carbon panel revealed other obvious defects:

• The panel that suffered the crack also was moved down about one-tenth of an inch.

• The panel also suffered a chip that measured three-quarters of an inch.

• The impact slightly pushed aside one of the seals between two carbon panels, opening a small gap.

• Finally, investigators found a 1-square-inch divot in a carrier panel.

Testing will be done to determine whether there is more damage to the carbon panel that can’t be seen. Thermographic tests will help determine the extent of cracks.

Although the long-awaited test proves that foam can damage a carbon panel, other questions remain. Mr. Hubbard said it is too early to know how such damage would affect a panel’s ability to protect Columbia from the scorching gasses of re-entry.

But he predicted that NASA would never let a shuttle fly if preflight inspections revealed the sort of damage caused by the foam strike during yesterday’s experiment.

“It is not anything we would fly with. It is a piece of hardware that would be rejected,” he said.

Proof that a foam strike can cause fatal damage to an orbiter shatters the argument NASA made after Columbia disintegrated during re-entry.

NASA officials said a piece of foam insulation from Columbia’s 154-foot external fuel tank could not have hit the shuttle with enough force to pierce the carbon panels lining the left wing’s front edge. NASA based its conclusions on information from Boeing Co., a space agency contractor that relied on a computer-modeling program.

A NASA spokesman at the test facility declined to comment.

Yesterday’s test was the first of its kind.

Columbia’s breakup led to one the worst tragedies in NASA history and triggered the most extensive review of the agency’s space-flight program.

Investigators also are looking into a range of other factors that were likely to have contributed to the disaster, from budgetary issues to management decisions.

About 60 observers sat under tents at the research center’s test site No. 4 to witness the experiment.

Astronauts Scott Altman and Greg Johnson were on hand. So were Boeing employees.

The test, planned for Thursday, was delayed twice, first by thunderstorms and then by a brief electrical problem yesterday.

When engineers from NASA and the Southwest Research Institute finally took their shot, the foam chunk rocketed down a 35-foot-long barrel at 768 feet per second. The foam piece, which measured 5.5 inches by 11 inches by 19 inches, splattered after impact.

Investigators recorded the experiment with 12 cameras.

Little damage was obvious immediately after the test, but investigators examined the carbon panel for nearly an hour before offering their initial assessment to a group of reporters.



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