Space shuttle crew scans for damage

By Irene Klotz

HOUSTON (Reuters) – The space shuttle Discovery crew
examined damage to the craft’s heat shield with laser scanners
on Friday while NASA’s chief on the ground expected engineers
would quickly fix the fuel tank problems that have again
grounded the fleet.

“We were actually quite surprised to hear we had some large
pieces of debris fall off the external tank,” Discovery
commander Eileen Collins said during the crew’s first in-flight
interview. “It wasn’t what we had expected.”

During Discovery’s launch on Tuesday on NASA’s first
shuttle mission since the 2003 Columbia disaster, a chunk of
foam nearly as large as the one responsible for downing
Columbia fell off Discovery’s fuel tank. A smaller chunk of
foam also broke off and is believed to have hit Discovery’s
wing, but did not cause any damage, deputy program manager
Wayne Hale said.

Columbia was destroyed because a 1.67-pound (0.75-kg) chunk
of falling insulating foam damaged heat panels on the ship’s
left wing, allowing superheated gases to blast into the
structure as the shuttle flew through the atmosphere for
landing on Feb. 1, 2003. Seven astronauts died when Columbia
broke up over Texas.

Discovery arrived at the International Space Station,
orbiting 220 miles above Earth, on Thursday for what was
expected to be an eight-day joint mission.

Hale said Friday NASA likely would extend Discovery’s stay
one day to transfer additional items to the outpost. Station
managers requested some shuttle gear, such as a computer and
additional oxygen and food, because the September shuttle
mission to the outpost likely will be delayed while NASA
resumes work on the shuttle fuel tank problem.

“We don’t expect this to be a long drawn-out affair,” NASA
administrator Michael Griffin said in a teleconference with
reporters.

On Friday, the Discovery crew used robotic arms aboard both
the shuttle and the station to position a 50-foot (15-meter)
boom outfitted with laser imagers to look at six damaged areas
of the heat shield that protects the shuttle’s underside.

Engineers believe the shuttle is in good shape to return to
Earth on Aug. 7 or Aug. 8, but wanted additional information
about the size and depth of six damage sites, Hale said.

The Discovery crew also prepared for the first of three
spacewalks planned during the flight. Astronauts Steve Robinson
and Soichi Noguchi are scheduled for a six-hour spacewalk on
Saturday at 4:44 a.m. EDT (0844 GMT) to test heat shield repair
techniques and to begin installing a new gyroscope.

The gyroscope is part of a system that keeps the outpost
properly oriented in space without depleting the station’s
limited supply of rocket fuel.

NASA has said it will not fly any more missions until the
shuttle tank debris problems are fixed, leaving the Russians
solely responsible for delivering cargo to the outpost.

“We said this was a test flight,” Griffin said. “We said
that because of the physics involved, the nature of the
problem, that we could not test this tank on the ground, in a
wind tunnel, in any other type of facility. We had to put it
back into flight to see how well we had done.

“We have hugely reduced damage to the orbiter,” he said,
noting that imaging experts had identified about 25 minor nicks
in Discovery’s heat shield, compared to an average of 150 on
previous shuttle missions.

NASA had planned to fly shuttle Atlantis on the second of
two test flights in September. The agency has one other
opportunity this year to launch a shuttle to the International
Space Station and Griffin refused to concede that the shuttle
fleet will miss those dates.

“We don’t start out by assuming we can’t succeed,” he said.
“My gut feel is that this is something that can be addressed
relatively quickly,” said former astronaut Richard Covey, who
co-chaired the task force that oversaw NASA’s implementation of
safety recommendations made by Columbia accident investigators.

“That’s what you do when you do test flights,” he said.
“You learn and then you go fix and then you fly again.”