In-Orbit Repair Considered for Atlantis

Jun 11, 05:00 AM

Current Headlines: By Traci Watson

Astronauts on space shuttle Atlantis may need to make an emergency repair in orbit to a damaged section of their spacecraft's heat shield, shuttle official John Shannon said Sunday.

During Atlantis' liftoff Friday, a corner of a heat-protection blanket peeled back, exposing a 4-by-6-inch wedge of an engine casing to the left of the ship's tail. The blanket shields the casing from the superheated gases that envelop the shuttle as it re-enters the Earth's atmosphere.

In its launch in early 2003, shuttle Columbia's heat shield suffered damage that was never detected. The interior of the ship's wing melted during re-entry, and the crew of seven was killed.

Shannon said no decision on a repair would be made until mission managers have more data on the damage and how and when it could be addressed. He said that he is leaning "maybe a little bit" toward doing a repair because engineers are worried that enough material might have peeled back to expose the heat-sensitive wall of the engine casing.

"I would just like to kind of avoid that scenario altogether and tack that blanket down," Shannon said. "If we can accommodate that, I think that's probably what we'll do."

The repair could be made on a spacewalk already scheduled for Friday, Shannon said. Or it could be made on an unplanned fourth spacewalk. An astronaut could tack down the errant piece of blanket. A spacewalker also could snip it off or squirt on some heat-protective glues from a heat-shield repair kit developed after the Columbia accident.

During re-entry, the engine casing heats up to 700 to 1,000 degrees. The graphite-epoxy material that makes up the wall of the engine casing starts to burn away at 250 degrees. There are several layers of material between the heat shield and the graphite-epoxy, but it's not clear whether the intermediate layers have also peeled away, Shannon said.

Today, Atlantis crewmembers will step into the vacuum of space to bolt an addition onto the International Space Station, a day after the shuttle pulled up there to drop off the piece and a new resident for the orbital laboratory.

Astronauts James Reilly and John "Danny" Olivas plan to exit the space station at roughly 3 p.m. ET for a spacewalk to attach a new girder with giant solar panels attached. The spacewalkers will spend roughly six hours stripping off the packing material that cushioned the girder during its ride into orbit.

If the additional solar panels aren't properly installed, the station will not have enough power to operate new research labs from Europe and Japan scheduled to be added in the next 12 months. At the moment, only the United States has a dedicated laboratory room aboard the station.

The astronauts also plan to fold older solar panels into storage boxes.

Among Atlantis' seven-man crew is astronaut Clayton Anderson, who will stay on the station for four months. Astronaut Sunita Williams, who has lived on the station since December, will return to Earth in Anderson's shuttle seat.

"Are you sure Clay is on board?" station commander Fyodor Yurchikhin radioed to Atlantis as the shuttle neared Sunday.

"Yes, we checked before we launched," deadpanned Atlantis commander Frederick Sturckow.

"Thank you very much. Suni is smiling," Yurchikhin said. Next week, Williams will break astronaut Shannon Lucid's 188-day record for the longest single stay in space by a woman.

His welcome assured, Struckow backed his ship slowly toward the station until the linking mechanisms on the two spacecraft locked. Two hours later, the doors between the two spacecraft opened and the shuttle astronauts floated into the station, receiving hugs from the station crew and presenting the station crew with Atlantis T-shirts. (c) Copyright 2005 USA TODAY, a division of Gannett Co. Inc.