NASA: Fuel-line cracks found in fourth space shuttle; entire fleet now affected

Thursday, July 11th 2002, 12:00 am

By: News On 6

CAPE CANAVERAL, Fla. (AP) _ The potentially dangerous fuel line cracks already discovered on three space shuttles also afflict Endeavour, the fourth and newest shuttle, NASA says.

The news Wednesday came as no surprise to the space agency, which has already delayed at least one flight and, despite weeks of exhaustive work, has no clear picture as to how or when the cracks occurred.

As of Wednesday afternoon, two cracks had been discovered in the metal liners of hydrogen-fuel lines inside Endeavour, the last of the four shuttles to be examined. The inspection was expected to continue into Thursday.

``We've got it on the other three, so we're not necessarily surprised to see that Endeavour has cracks, too,'' said NASA spokesman Bruce Buckingham. He added: ``I think a reasonable person can assume we've been flying with these cracks.''

The problem was first detected three weeks ago on Atlantis. Inspections quickly uncovered cracks in the plumbing of Discovery and then Columbia. The work on Endeavour had to wait until the shuttle returned from Edwards Air Force Base in California, where it landed June 19 following a space station visit.

Alex Roland, a former NASA historian who teaches at Duke University, said he is just as perplexed as everyone else. The fact that space shuttles of different ages are exhibiting the same trouble makes age an unlikely cause, he said.

Columbia, the oldest shuttle, has been flying for 21 years, Endeavour for 10. NASA plans to keep the fleet flying for at least another decade.

``The only thing that it reinforces, to me,'' said Roland, ``is that a large part of our space program is dependent upon a single, quite marvelous, but nonetheless fragile piece of technology. And when something like this happens, it can grind everything to a halt.''

Columbia's scientific research flight with the first Israeli astronaut, which had been scheduled for a July 19 liftoff, is on indefinite hold. The launch dates of the two other shuttle flights this year, both to the international space station, are also in question.

The space shuttle fleet is NASA's only means of traveling to the space station. Russia provides its own transportation.

NASA's concern is not that the 1-foot-diameter fuel lines might leak, but that the cracks might grow and that metal chips might break off and end up in an engine. That could lead to an engine shutdown during launch, with possibly catastrophic results.

The cracks are between one-tenth of an inch and three-tenths of an inch in length, and are located in liners used to direct the flow of super-cooled hydrogen fuel to the main engines.

Buckingham said there is a possibility engineers will conclude that the spaceships can fly safely with the cracks and that no repairs are needed. But if the cracked liners need to be replaced, it could take months to manufacture new parts. No spares are available.

Seven engineering teams, involving workers around the country, are working practically nonstop to determine the severity of the problem and devise solutions.

Despite the problem, NASA is still working toward a late August launch of Atlantis and an October launch of Endeavour. Both are space station construction missions; the latter also is the ride home for the one American and two Russians who moved in last month for a 4 1/2-month stay.