Next Shuttle Flight: March at the Earliest

The space shuttle will not fly again until at least March, and the next mission will be flown by Discovery, not Atlantis as had been planned, NASA Administrator Michael D. Griffin said Thursday.

The delay was attributed to foam shedding from the external fuel tank during launch.

“It looks like we are going to have to do some repair on the tanks,” said William H. Gerstenmaier, whom Griffin appointed two days ago to head NASA’s return-to-flight program.

Gerstenmaier said the external fuel tanks now at Kennedy Space Center in Florida would be sent to the manufacturer in New Orleans for repair or replacement.

“We’re starting to understand the areas” that need more work, he said, and consequently, potential launch dates in September, November and January “are pretty much off the table.”

The delay will allow the agency to substitute Discovery for Atlantis in the next launch.

Using Discovery will in turn provide more time to prepare Atlantis for the following mission, in which the shuttle will carry a heavy truss to the International Space Station.

Atlantis can handle heavy lifting better than Discovery or Endeavour.

Discovery was to begin its return to Kennedy from Edwards Air Force Base in the Mojave Desert aboard a specially modified 747 this morning. The flight had been delayed by runway flooding in a rainstorm and by difficulties attaching a fairing to cover the shuttle’s three engines.

The 747 will carry the shuttle to a military base in Texas, then proceed to Florida on Saturday, NASA said.

Discovery landed at Edwards last week, completing the first space shuttle mission since Columbia disintegrated on reentry in February 2003. The leading edge of Columbia’s wing had been damaged by foam that fell from the external fuel tank during launch.

NASA “didn’t look in detail at foam shedding for 113 flights, and shame on us,” Griffin said. That was a mistake “that will be examined in textbooks for years to come.”

During Discovery’s launch, a large piece of foam again fell from the tank, though it did not hit the craft.

That was “very embarrassing,” Griffin said.

NASA has grounded all shuttle flights until the foam problem has been solved.

Griffin and Gerstenmaier spoke a day after the formal release of a report from the Stafford-Covey Return to Flight Task Group, charged with reviewing NASA’s safety improvements to the shuttles.

The gist of that report had been released before Discovery’s launch.

The panel said that NASA had not completed three of 15 major post-Columbia objectives, the most important of which was completely addressing the foam problem.

But most panel members said they thought the shuttle was safe to fly.

The published report contained comments from seven members who dissented.

They argued, among other things, that the agency had neglected some safety improvements in its rush to get back into space.

Griffin said he had not read the minority reports and would not comment on them until he had.