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Discovery ends mission with
perfect landing in California.
By Phil Long
CAPE CANAVERAL - The shuttle Discovery completed its dramatic and
historic ''return-to-space'' voyage Tuesday morning -- but only after
having to make an extra 18 trips around the Earth and land in the dark
at Edwards Air Force Base because of poor weather conditions at the
Kennedy Space Center.
The shuttle and its seven-member crew rolled to a stop on the concrete
Runway 22 at the Mojave Desert air base just after 8:11 a.m. EDT,
returning to Earth with more than 3.5 tons of equipment and trash from
the International Space Station. The shuttle covered more than 5.8
million miles on its journey.
''Wheels stop,'' shuttle commander Eileen Collins crackled on the radio
when the shuttle stopped rolling.
''Roger, wheels stop Discovery,'' replied Ken Ham, Mission Control
communications liaison in Houston. ``And congratulations on a truly on a
truly spectacular test flight.
''Welcome home, friends,'' Ham said after first ticking off the first
names of the seven astronauts.
''Thank you. They are great words to hear,'' Collins said. ``We're happy
to be back and congratulate the whole team for a job well done.''
Then it was immediately back to business as Collins made reference to
the page, chapter and line on the book containing the list of things to
do as the shuttle sat at the end of the Edwards runway.
The touch-down marked the 50th time a shuttle has landed at Edwards,
NASA's secondary choice for a landing site if Kennedy is not open.
The crew -- making the first shuttle voyage since the Columbia disaster
in January 2003 -- included Collins, pilot Jim Kelly and mission
specialists Siochi Noguchi, Andy Thomas, Wendy Lawrence, Charlie Camadra
and Stephen Robinson.
The astronauts' families and friends, who have been waiting anxiously
for that moment at the Kennedy Space Center, had to watch the shuttle's
picture-perfect touchdown via TV hookup. They are scheduled to reunite
with the astronauts on Wednesday at the Johnson Space Center in Houston.
The landing celebration was tempered with looming concerns about shuttle
safety that have indefinitely halted future launches. And the joy was
dampened by memory of the seven Columbia astronauts who were killed just
minutes before their landing.
The 14-day mission -- one day longer than scheduled -- was hailed as a
success by all standards. One of the achievements was the first-ever
intensive inspection of the shuttle's thermal tile protection system by
space-station astronauts, who beamed high definition images back to
Mission Control in Houston.
Shuttle astronauts also replaced a malfunctioning gyroscope that helps
with the orbiting lab's navigation, and they bolted an exterior storage
facility to the space station.
Despite the successes, the mission also encountered several potentially
serious safety problems. One of them led to an unprecedented repair job
of the shuttle in space. Astronaut Stephen Robinson nimbly and quickly
removed two slivers of fabric sticking up from between thermal
protection tiles, which engineers said might cause damaging overheating
on return.
Later, engineers agonized over another possible problem -- a small tear
in a thermal insulation blanket near the cockpit window -- that would
have required an unscheduled fourth spacewalk. But not having anything
on board to repair the tear, NASA officials decided against asking
Robinson to try to remove or patch it.
The more serious problem that affects the long-term future of the
shuttle was a chunk of foam insulation broke off the main fuel tank
while Discovery was taking off on July 26.
Though the piece did not strike the shuttle, NASA officials decided
there should not be another shuttle launch until engineers figure out a
remedy for the same type of problem that led to the Columbia tragedy.
Columbia was doomed when a chunk of foam broke off during launch and
inflicted an undetected puncture in its left wing. The hole didn't
affect the flight into space, but during reentry, the gash allowed hot
gases to pour into the wing. The ship broke apart after it reentered the
Earth's atmosphere on Feb. 1, 2003.
After 2 ½ years of research and millions of dollars in fixes, officials
thought foam debris would not be a problem on the redesigned fuel tank
that Discovery used.
Discovery's liftoff was delayed for nearly two weeks because of a spotty
fuel-tank gauge detected shortly before the originally scheduled launch
on July 13 -- a problem NASA engineers never completed figured out. But
the gauge was working when the launch finally took place.
The final challenge faced by the Discovery crew was landing the big
orbiter. Mother Nature, not any technical issues, played a critical role
in that exercise.
The shuttle was scheduled to land before dawn on Monday at its home base
at the Kennedy Space Center. But low-hanging clouds that affected
visibility caused mission managers to wave off landing twice and order
the crew to circle the Earth for next 24 hours.
This morning, NASA had two more chances to land Discovery at Kennedy --
at 5:07 and again at 6:42 a.m.
About 1 a.m. skies were clear over the Space Coast. Conditions were less
humid and less conducive to the low clouds that caused NASA managers to
wave off Monday's landing attempts.
But around 1:30 a.m., several patches of clouds popped up rapidly. Some
had lightning.
NASA safety rules say there can be no rain showers or lightning within
30 miles of the shuttle landing facility because raindrops can damage
the shuttle's sensitive thermal heat tiles.
NASA would have preferred to land at the Kennedy Space Center because it
costs about $1 million to ferry the shuttle back to Florida atop a
specially modified Boeing 747.
Source:
The Miami Herald
August 9, 2005
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