PERFECT LANDING CREW, CRAFT SAFE AT EAFB.
EDWARDS AFB - Back safely on Earth after returning America's shuttle fleet to space for the first time in 2 1/2 years, shuttle Discovery is getting ready for its flight home to Florida and an uncertain future.
America's oldest surviving space shuttle made a picture-perfect landing before dawn at Edwards Air Force Base, but the next shuttle launch remains uncertain because of continuing problems with fuel-tank insulation coming loose at launch - the problem that doomed Columbia in 2003.
``The shuttles will not last forever. We do see some signs of aging in all the work we do,'' Discovery's commander Eileen Collins told reporters after landing at Edwards. ``We fixed what needed to be fixed. We realize more needs to be done.''
In the first flight since shuttle Columbia came apart Feb. 1, 2003, killing all seven astronauts aboard, Discovery spent nearly 14 days in orbit.
Its international crew delivered nearly six tons of supplies to the International Space Station, installed an exterior platform and a replacement gyroscope, and loaded up space station trash to take home.
But problems arose even while Discovery was in space.
In what NASA calls an unprecedented event, astronaut Steve Robinson climbed out of the spacecraft and maneuvered with the help of a robotic arm around to its underbelly to pluck protruding gap fillers from between heat-resistant tiles.
Even worse, a day after Discovery blasted off, NASA officials put a hold on future launches after video footage showed the external fuel tank dislodging a piece of foam insulation much larger than officials believed could come off.
NASA officials expect they can get the problem fixed before the launch window for shuttle Atlantis to rendezvous with the space station closes Sept. 24, but they aren't certain.
NASA and Lockheed Martin set teams of engineers to work studying why the chunk came loose despite all tests and changes in fabrication procedures since the Columbia disaster.
Insulation foam has come off the fuel tank since shuttle launches began more than 20 years ago, but NASA engineers never regarded it as anything other than a nuisance and a maintenance chore before the next flight.
The polyurethane-like foam deters ice from forming on the tank's exterior from the intense cold of the liquid hydrogen inside, and also protects the thin skin from the heat of speeding through the atmosphere after launch.
NASA officials never imagined that a chunk could damage the shuttle's thermal insulation seriously enough to do what happened to Columbia: let the blowtorch heat of re-entry melt the spacecraft's aluminum structure.
``This was the central mistake to the loss of (Columbia). It was not thought to be anything other than a maintenance and turnaround issue,'' NASA administrator Michael Griffin said at a media briefing Friday.
Griffin added: ``We are learning our way. The United States has conducted 145 exactly manned spaceflights in 44 years. A student pilot has taken an airplane off the ground and landed it more times than that by the time he gets his ticket. We are at the dawn of this enterprise, not its maturity.''
Discovery's mission was considered a test flight, NASA officials say. The astronauts used new equipment and techniques for checking for damage, and practiced making tile repairs.
Long-range missions to the moon or beyond will require in-flight repairs, the astronauts say.
``We made the first baby step of that, I think, on this mission,'' Robinson said. ``It may be a long road ahead but we're very encouraged by this first step.''
The return to space proved an eye-opener for hundreds of thousands of Southern Californians, jolted awake by the distinctive double sonic booms of the returning shuttle for the first time in more than three years.
Coming in over the Ventura County coast on its way to Edwards, the shuttle's booms were loud enough to set off car alarms across the San Fernando, Santa Clarita and Antelope valleys.
Calls from people startled out of their pre-dawn sleep lit up the switchboards at the Lancaster and Palmdale sheriff's stations. Some callers thought the noise was gunfire, or an intruder in their home.
``They didn't know what the 'boom' was,'' said Deputy Rick Nolte, who heard the shuttle pass overhead as he drove to work at the Lancaster sheriff's station.
Discovery's crew said they thought both before and after their flight about what happened to Columbia's crew. A photo of Columba's seven astronauts hung inside Columbia.
Pilot Jim Kelly said he watched his gauges more closely than usual during re-entry to look for any sign that what happened to Columbia was happening to Discovery, whether or not there was anything he could do about it.
``For me, there was a moment of trepidation right before Eileen hit the execute for the de-orbit burn, because once you do that, you're coming home,'' Kelly said.
Collins, who was on her fourth space flight, said the astronauts all were aware of the risks and accepted them.
``The Columbia crew believed in the mission. We are continuing the mission,'' Collins said. ``It's very important to us that that mission of space exploration goes on. This mission is very important: exploring space and making life on Earth better for all of us.''.
(1 -- color) Space shuttle Discovery is towed off the runway at Edwards Air Force Base, where it landed smoothly a little after 5 a.m. Tuesday. Next week, it will leave California, riding piggyback atop a modified Boeing 747 back to Cape Canaveral.
(2 -- ran in AV edition only) Space shuttle Discovery makes a pre-dawn landing at Edwards Air Force Base after being in space for 13 days.
Gene Blevins/Special to the Daily News
(3 -- color) Shuttle astronauts, from left, Eileen M. Collins, James M. Kelly, Soichi Noguchi, Stephen K. Robinson and Charles J. Camarda talk about their successful mission.