WASHINGTON (AFP) - NASA's prestigious image is being chipped away at by the Columbia Accident Investigation Board, which has unearthed shortcomings so serious as to put astronauts' lives in potential danger.
The board's latest discovery, even if it is not directly related to the February 1 accident in which Columbia's seven crew members were killed on reentry, could keep the remaining three shuttles grounded longer than anticipated.
Thursday, investigators said pieces from exploding bolts that allow the external fuel tanks to separate from the booster rocket could strike the shuttle itself.
The problem threatens to push back NASA's countdown for a relaunch of shuttle missions. NASA shuttle program boss Sean O'Keefe had hoped to return them to service in early 2004.
About two minutes after liftoff, the external tank runs out of fuel and must be jettisoned. The bolts explode, breaking into two pieces, each of which is to land in a bolt catcher designed to prevent it from striking the shuttle orbiter. However, the bolt catcher may not be up to the job.
"The bolt catcher is not as robust as we would want," chairman Harold Gehman said.
The board has already found that a few pounds of insulating foam that fell away from Columbia's fuel tank on takeoff led to the ship's breakup February 1.
However, each half of the exploding bolt weighs about 40 kilograms (80 pounds).
"It has the potential of being catastrophic in the future," board member John Barry said.
However, the board members said, the bolt problem is not linked to the Columbia accident.
That was apparently caused by a hole that the falling foam opened in the left wing on takeoff January 16. On reentry, the fissure allowed superheated gases to enter and weaken the structure as the craft hurtled toward Earth.
NASA approved the bolt catcher in 1979 but has never tested it. The government space agency said the part never posed a risk.
The discovery tops the board's long list of problem procedures.
NASA engineers spotted the tumbling foam in films taken of the liftoff, but dismissed it as inconsequential. It may have been observed on previous flights as well, without being addressed.
Investigation board member Douglas Osheroff said Thursday that a test run in his kitchen for less than 100 dollars could have refuted NASA's theory of how the foam broke loose from the fuel tank.
The Nobel prize-winning physicist said the cause was simple condensation and reheating. NASA said that gas trapped in the foam expanded as the shuttle gained altitude, causing the rupture.
"Hokum!" Gehman huffed.
The investigation board is still not convinced that NASA measures up to the demands of space flight safety, of forestalling problems or of dealing with them when they come up.
Tom Young, a former NASA manager told the board Thursday that the agency should run tests on all the shuttle components, a task made urgent by aging equipment.
The board is expected to deliver its final report to Congress in the next few months.
Yahoo News