Marc Flemming
Renovator
offline
Registered: Jan 2003
Local time: 08:20 PM
Location: Santa Cruz
Posts: 3663
|
An investigator looking into what caused the disintegration of the space shuttle Columbia as it came back to Earth in February said Monday the "smoking gun" at the heart of the accident has been found.
The probable answer came during a series of tests that involved striking a replica of the shuttle's wing with pieces of foam to recreate the strike on the leading edge of Columbia's left wing 82 seconds after liftoff January 16.
A piece of foam fired at the replica at about 500 mph punched a hole 16-inches in diameter in the reinforced carbon material, as onlookers gasped at the Southwest Research Institute.
"We have found the smoking gun," said Scott Hubbard, a member of the Columbia Accident Investigation Board.
"The test we conducted ... demonstrates that this is in fact the most probable cause creating the breach that led to the accident of the Columbia and the loss of the crew and vehicle," Hubbard added.
This latest effort to determine what caused the Columbia disaster cost $3.4 million, according to The Associated Press.
The shuttle broke up as it re-entered Earth's atmosphere February 1, spreading debris across large parts of Texas and Louisiana and killing all seven crew members aboard.
From the beginning of its investigation, the CAIB had theorized that the foam strike was one of the more likely causes of the accident.
Hubbard said he and other observers to the foam test felt a "visceral reaction to the hole."
"It was so dramatic, I felt surprise at how it appeared, such a dramatic punch through," he added. "But it is the kind of damage, the type of damage, that must have occurred to bring down the orbiter."
The foam hit with the force of 1 ton and the impact was captured by 16 high-speed cameras while hundreds of sensors measured stresses and other conditions, AP reported.
"There's a lot of collateral damage," said Hubbard.
Investigators believe this test leaves little room for doubt that Columbia and her crew were doomed one minute and 22 seconds into their mission.
That's when video of the Columbia launch showed a piece of the foam that insulates the shuttle's external tanks break off and bounce off the left wing.
NASA's shuttle team knew about the foam strike shortly after launch, but presumed the light material could not pierce the tough carbon panels that protect the wings.
But the breach that the foam strike caused in one of the reinforced carbon panels allowed 3,000 degree Fahrenheit plasma to blowtorch the aluminum structure of the wing as Columbia returned to Earth, ultimately causing the orbiter to break apart.
Hubbard said the board may recommend that future shuttle flights have better imagery on takeoff and the capability to perform in-orbit inspection and repair.
Source: CNN
|
07-08-2003 07:46 PM
