Astronaut Removes Cloth From Discovery's Belly

HOUSTON -- During a spacewalk on Wednesday, an astronaut from the shuttle Discovery successfully removed two pieces of protruding cloth from the underside of the craft that NASA scientists feared would pose a risk of overheating during re-entry.

The two bits of cloth, known as gap fillers, had been sticking out about an inch near Discovery's nose. NASA ordered today's spacewalk by Stephen Robinson because analysts were unable to allay concerns that the protrusions could cause unusual and potentially dangerous patterns of heating on the bottom of the shuttle and along the leading edge of the wings.

This if the first time in the history of the shuttle program that heat shield repairs have been attempted while the craft is in orbit. The operation, which took days of intense planning, seemed routine as it was shown on live television.

As Robinson was moved into place under the shuttle via a robotic arm, he reached out his gloved right hand, and gently tugged on the gap filler. It came out using 3.3 kilograms of force. "It's coming away very nicely," said Robinson, as the shuttle traveled 350 kilometers above the Earth -- over Massachusetts.

Several minutes later, Robinson was positioned in front of the second protruding gap filler. This time, the gap filler simply slid out -- the reddish colored glue on it evident in television pictures.

"That came out very easily, probably even less force," said Robinson.

He placed both pieces in a trash bag to be examined later.

After the operation was finished, Robinson said to the shuttle pilot, James Kelly, who goes by the nickname Vegas -- "Vegas, that was the ride of the century." Drawing on experience, mission managers had said they were comfortable with protrusions of no more than a quarter of an inch near the shuttle's nose.

The stiff, thin pieces of ceramic-treated fabric act as spacers, keeping delicate insulating tiles from grinding together during the shuttle's rattling ascent and as its body expands and contracts in extreme temperatures.

"Like most kinds of repairs, it's conceptually very simple," Robinson said in a news conference Tuesday with all seven astronauts.

"But it has to be done very, very carefully. The tiles, as we all know, are fragile." A crew member can cause damage just by bumping into them.

Robinson said Tuesday that his main concern would be watching his head. "I'll be leaning in toward the orbiter," he said, adding that his helmet added inches to his height. "So that's what I'll be most careful with."

If the strips had not yielded so easily, Robinson was prepared to try forceps, a special hacksaw and scissors developed for spacewalks.

Over three days of intense analysis, mission managers struggled to balance the risks of a spacewalk -- it was the first to the underside of the shuttle and was the first repair to an orbiting shuttle -- with the risks of re-entering Earth's atmosphere with protruding gap fillers. Astronaut Charles Camarda said that "in this particular case, it was a very close call."

The gap fillers were not the only repair work that could be on the agenda. At a briefing on Tuesday evening, mission managers said analysts were studying the potential risks of a damaged thermal-insulation blanket near the window on the commander's side of Discovery. The blanket came loose, apparently because it was hit by debris during ascent, said Wayne Hale, the deputy manager of the shuttle program.

The shuttle team on the ground must determine whether the blanket could fly off during re-entry and strike the shuttle, Hale said, and whether to use the day added to the mission to conduct one more spacewalk to repair it.

On Tuesday, the astronauts received a call from the White House. Seen via video link, they bobbed gently as they waited for U.S. President George W. Bush to get on the line, their hair puffing up without the restraining force of gravity.

Speaking from the Roosevelt Room, Bush said: "I just wanted to tell you how proud the American people are of our astronauts. I want to thank you for being risk takers for the sake of exploration."

Discovery's commander, Colonel Eileen Collins, who is retired from the Air Force, replied: "We all enjoy what we're doing. We really believe in our mission, and we believe in space exploration and getting people off the planet and seeing what's out there. The steps we are taking right now are really worth it."

The president finished by saying: "Thanks for taking my phone call. Now get back to work."