Still no fix for problem that doomed space shuttle

1.00pm

CAPE CANAVERAL - One year after a highly critical report urged Nasa to develop the means to fix a broken space shuttle in orbit, the US space agency still cannot repair a hole the size of the one that doomed the seven Columbia astronauts, Nasa said on Thursday.

A piece of foam that broke off Columbia's external fuel tank 81 seconds after liftoff left a gash in the left wing and caused the 100-tonne ship to break up as it re-entered the atmosphere in February 2003.

Since then, Nasa has experimented with various patches but has found none that could resist the 3,000 degree F (1650 degrees C) temperature of re-entry, said Bill Parsons, the shuttle programme manager, who spoke to reporters on the anniversary of the Columbia Accident Investigation Board's report.

"We've made a lot of progress, but we've not been able to come up with an over-wrap in this time frame that would allow us to fix a large hole," said Parsons. "Our expectation is that we'll fix the tank and there won't be anything like that we'll have to deal with."

This month, officials at the New Orleans plant where Lockheed Martin Corp assembles the $40 million fuel tanks, said they were certain the same accident would not occur again because they would, on future missions, remove the 0.68 kg piece of foam that broke away during Columbia's ascent.

But these officials made clear that they had not yet met the exacting standards set by the accident board that require nothing heavier than a fraction of an ounce of foam to come off the tank after liftoff.

Most shuttle flights, since the programme started in 1981, have resulted in at least some foam breaking off.

The fuel tank for the return-to-flight mission in 2005 is due to be sent from New Orleans to the Kennedy Space Centre launch facility in Florida in early November.

Despite the obstacles, Nasa officials said they remain upbeat that the shuttle Discovery will make a launch window next year that runs from March 16 to April 18.

The accident investigation report released last year excoriated the agency for a number of failings, including an operating culture that suppressed dissent.

Thomas Krause, president of Behavioural Science Technology Inc., a consultant brought in by NASA to help transform that culture, said there is ample evidence that employees are no longer afraid to speak up about safety and engineering issues.

But he acknowledged that with every employee now having a voice, there was "no clear cut answer" to determining what is acceptable risk in an agency where the mission requires putting astronauts in extraordinarily risky environments.

Shuttle astronauts sit atop a rocket that could explode like a small nuclear bomb and the craft hurtles across the sky at 8km per second.

"Judgments have to be made," said Krause. "It's not for us to say how those judgments should be made, but to say that someone should be looking at that aspect very carefully."

- REUTERS