Is Shuttle Shipshape?

NASA Says Discovery Looks Good But More Checks Are Being Done

(CBS/AP)  Discovery's astronauts will be unloading 13.6 metric tons of supplies onto the space station Friday.

The astronauts will also be checking the shuttle for damage, after getting the word from NASA Thursday that a chunk of foam may have hit a wing during liftoff.

In an interview from space Friday with CBS' Peter King, shuttle commander Eileen Collins said she was disappointed with the debris mishap, but insisted it was something "We can fix."

Despite the latest development, officials said Discovery still looks safe to fly home in a week, but stressed it will be another few days before the space agency can conclusively give the shuttle a clean bill of health.

"They want to get all of the angles to make sure that we haven't missed any small thing," said Wayne Hale, deputy shuttle program manager.

NASA said Thursday that Discovery escaped damage from the potentially deadly chunk of foam that broke off from the fuel tank, but may have been struck in the wing by a much smaller piece.

Even if the small foam fragment did hit, engineers believe the impact caused no damage of concern, Hale said.

NASA analysts have identified 11 areas - including Discovery's wings, nose and belly - they want astronauts to take another look at Friday, using the shuttle's new laser-tipped extension to its robotic arm.

NASA suspended future shuttle flights earlier this week after learning that the big piece of foam insulation, which weighed less than a pound, flew from Discovery's external fuel tank. It was an alarming repeat of the problem that doomed Columbia more than two years ago. The foam missed Discovery.

The piece of insulating foam that broke off Columbia's external tank during liftoff knocked a hole in its left wing. The searing gases of re-entry melted the wing from the inside out, causing the spacecraft to disintegrate as it headed to Cape Canaveral, Florida in February 2003. All seven astronauts aboard died.

The small bit of foam that may have hit Discovery's right wing came off about 20 seconds after the big piece, and was from the same general area, Hale said. None of the newly installed wing sensors detected anything unusual.

An earlier inspection with the laser didn't reveal any damage. Camera views during liftoff were inconclusive because the foam tumbled out of sight.

NASA already has run tests showing that if the foam did strike the wing, it would have exerted just one-tenth of the energy needed to cause worrisome damage, Hale said.

"So we feel very good about this," he said.

CBS News Space Consultant Bill Harwood says Discovery's crew might have dodged a bullet when a piece of foam debris broke away from an aerodynamic ramp on the side of the ship's external fuel tank during launch Tuesday.

Had the foam broken away earlier, when the shuttle was deeper in Earth's atmosphere, the chunk could have hit the orbiter with potentially catastrophic results, engineers said today.

"The piece in question here was pretty close to the same size to the one that brought down Columbia," James Hallock, a member of the Columbia Accident Investigation Board, told CBS News. "The good news at this point is it occurred at such high altitude that it really didn't slow down much, you could see it on the camera, there weren't enough molecules to really slow it down so if that did hit something, it probably wouldn't do too bad."

Also on the agenda for Friday, astronauts will be preparing tools for the mission's first spacewalk, set for Saturday. Astronauts Stephen Robinson and Soichi Noguchi plan to exit the shuttle for three orbital outings.

During the spacewalks, the pair will try out new repair techniques for the shuttle's tiles and delicate carbon panels; replace a gyroscope, which helps steer the space station; and install a storage platform on the station.

NASA also said it was trying to come up with ways to leave more water and oxygen aboard the space station than initially planned, given the grounding of its shuttle fleet. Water is generated as a byproduct of the shuttle's fuel cells, which power the spacecraft.