July 17, 2006

Space shuttle lands in Florida

By Irene Klotz and Tom Brown

CAPE CANAVERAL, Florida (Reuters) - The U.S. space shuttle
Discovery landed smoothly in Florida on Monday, ending a
successful 13-day mission that NASA hopes will return the
U.S.-built shuttles to regular space flights three years after
the Columbia disaster.

Double sonic booms thundered over central Florida as the
shuttle glided through partly cloudy skies toward a
three-mile-long runway at the Kennedy Space Center.

Commander Steve Lindsey gently steered the shuttle through
a series of turns to slow the winged spacecraft down before
landing at 9:14 a.m., capping a 5.3 million mile


"It was an enormously successful flight," NASA
administrator Michael Griffin told a post-landing news
conference. "We're back on track."

Griffin sounded a cautionary note about what was a
make-or-break mission for the U.S. space agency, however, even
as he described Discovery as "the cleanest" or most damage-free
shuttle on its return to Earth.

"Obviously, this is as good a mission as we've ever flown
but we're not going to get overconfident," Griffin said.

He said before Discovery's launch he would move to pull the
plug on the shuttle program if it were marred by any further
accidents or serious technical problems.

Discovery's flight was the first in a year and only the
second since the 2003 Columbia disaster. NASA has spent more
than $1.3 billion on safety upgrades since the accident, which
killed seven astronauts and brought construction of the $100
billion International Space Station to a halt.

The agency's chief concern has been to fix foam insulation
on the shuttle's external fuel tank, which triggered Columbia's
demise. The doomed spacecraft was hit by a piece of falling
foam during launch, opening a hole that let in super hot
atmospheric gases during re-entry 16 days later.


NASA had hoped to resume space station construction last
year, but Discovery's tank shed large pieces of foam during its
July 2005 liftoff, forcing the renewed grounding of the fleet
while space agency experts worked on the problem.

When the shuttle was launched again on July 4, its tank
lost only small pieces of foam, none a threat to the spaceship
or its crew. Discovery reached the space station two days
later, delivering more than 2.5 tons of supplies.

British-born astronaut Piers Sellers and American Michael
Fossum made three spacewalks, including a repair of the
station's transporter so construction of the half-built space
station can resume. NASA hopes to launch its first station
assembly mission since the Columbia accident around August 28.

The shuttle dropped off German astronaut Thomas Reiter at
the station, giving it a full three-person crew for the first
time in three years.

Spacewalkers Sellers and Fossum also tested techniques to
reach and repair heat shield damage should it occur. The work
is critical for a proposed fifth and final servicing mission to
the Hubble Space Telescope. Griffin said a decision about
whether to service Hubble will be made by this fall.

The space agency plans to fly 16 shuttle missions,
including two more this year, to finish the space station
before the fleet is retired in 2010. NASA will focus after that
on returning astronauts to the moon and heading for Mars.

Discovery commander Steven Lindsey told reporters the
success of his mission opened the door to "another phase" in
the shuttle program.

But he stressed that Columbia should never be forgotten,
suggesting complacency was NASA's worst enemy. "I don't think
we want to ever put Columbia behind us," he said. "I think we
need to remember the lessons learned from Columbia."

(Additional reporting by Deborah Zabarenko in Cape