The U.S. space shuttle Discovery
crew carried out an unprecedented remote control inspection of the orbiter's surface Wednesday, looking for any damage of the kind that caused the break up of the shuttle Columbia
in 2003. Mission officials say the debris that fell off Discovery
during its launch Tuesday does not appear to pose a significant threat to the orbiter.
For the first time in the shuttle fleet's 24-year launch history, the space agency, NASA, has committed more than 100 cameras and radars to photograph a shuttle launch from every angle and hundreds of engineers to analyze the images. In addition, the Discovery astronauts have used hand-held cameras and cameras and laser beam sensors at the end of the shuttle's robot arm to inspect the spacecraft in orbit.
Images taken during Tuesday's launch showed a chip coming off one of the shuttle surface tiles that protect the orbiter from the searing heat of re-entry. They also showed a larger piece of debris. Launch debris is of grave concern ever since 2003 when a piece of hard foam broke away from shuttle Columbia's external fuel tank during liftoff and punctured a hole in its wing, dooming it to disintegrate.
But Discovery Flight Director Paul Hill says that engineers currently have no significant concern based on what they have seen so far on this mission. He adds, however, that the analysis is incomplete.
"We aren't prepared to say that this doesn't need to be repaired," he said. "We're not prepared to say this does need to be repaired. We've seen some things in video and some of the other imagery that causes some concern among the experts. The imagery folks saw things that they thought were indications of debris, in a couple of cases indications of damage on the vehicle. They are doing everything they can to turn that into real engineering data that can tells us if, in fact, we have damage."
Mr. Hill says if damage did occur, mission engineers must assess whether it needs to be fixed in orbit or not. Later in the mission, Discovery astronauts are to conduct a spacewalk to test new procedures for repairing small cracks and other surface damage, but it is unclear whether they would turn their attention to the particular tile in question.
This is the first shuttle flight since Columbia's 2003 demise. Discovery is to dock with the International Space Station Thursday with new supplies and equipment.
In the past two years, NASA has modified the external fuel tank and added the imaging system to ensure that as little debris as possible flies off shuttles and the tanks, something that has occurred regularly since the first launch in 1981.
Mr. Hill says the imagery task adds a heavy new burden to the shuttle team, but is worth the extra work if it saves astronauts' lives. He hopes for a time when less imaging will be necessary.
"Our goal, though, is to demonstrate in a number of ways that it's not required, and that we can wait and inspect only if we think we have damaged the vehicle going uphill [during ascent] and we have a reason to worry about it," he said.
Discovery and its seven astronauts, including one Japanese crewmember, are to return to Earth August 7.