7/13/2005

The Space Shuttle


We all wish the shuttle and her Crew , Good Luck and a safe voyage and come back home mission completed...

Liftoff set for 2:51 p.m. with high stakes in mind

By Jeremy Manier
Tribune staff reporter
Published July 13, 2005


CAPE CANAVERAL, Fla. -- After 2 1/2 years of planning and healing at NASA, the shuttle Discovery is scheduled to lift off on Wednesday with a new arsenal of tools designed to detect the kind of external damage that doomed the last flight of the shuttle Columbia.

The space agency also hopes the mission will help mend deeper wounds left when Columbia disintegrated in the skies over Texas as it returned to Earth, killing its seven-member crew.

Workers got a scare on the pad late Tuesday when a temporary protective cover for one of the shuttle windows fell and damaged two heat-resistant tiles, but officials said the section was easily replaced and the mishap should not delay the launch.

A successful mission would start to redeem the program and open a path to exploration of the moon and Mars; a failure could end America's manned presence in space as it exists now.

With the high stakes in mind, NASA engineers worked to address late issues raised at a lengthy flight-readiness meeting that one participant described as collegial yet spirited--a sign of the renewed focus on safety in the wake of Columbia, agency officials said. NASA chief administrator Michael Griffin said Tuesday that the remaining problems had been fixed, and the shuttle was "go" for launch.

"We have come through a very difficult period at NASA," Griffin said. "We're back online and ready to go."

One lingering concern is the weather. In addition to an increased chance of thunderstorms, officials said, unusual weather-balloon readings from the upper atmosphere could delay the launch, planned for 2:51 p.m. Central time.

Although most shuttle missions garner scant attention, this pivotal launch has drawn more than 2,600 media representatives from around the world, with thousands more tourists camping near the swampy confines of the Kennedy Space Center. Joseph Golden, an aerospace worker from Cleveland, drove to Florida with his wife and two young sons to see a piece of history.

"This is a once-in-a-lifetime event," said Golden, who has always dreamed that people one day would colonize the moon.

The spectacle they came to witness will be more than a simple test flight to restore NASA's confidence. During the 13-day mission to the International Space Station, the Discovery crew will test several new ways of checking the shuttle for damage, including a boom that will scan the underbelly with lasers. The crew will conduct three space walks and try out "goo-guns" designed to fill in damage to the tiles and panels that protect the spacecraft from intense heat during re-entry.

They also will expand, resupply and repair the space station, which, under a new plan, could serve as an emergency refuge for the shuttle crew if the vehicle were unable to return to Earth. Servicing the station may be the shuttle's most urgent task, said Bill Gerstenmaier, space station program manager.

"We can't continue assembly of the space station without the shuttle," Gerstenmaier said.

Many of the changes for this mission stemmed from 15 specific recommendations the Columbia accident board issued in 2003. NASA has been unable to comply with three of those goals, including one that called for reliable techniques to repair damage while in orbit; the "goo-guns" are still experimental. Still, agency officials said the improvements so far are enough to make the mission safe.

One major change is an unprecedented ability to take images of the shuttle as it ascends to orbit. Although NASA took film of Columbia during its launch, one camera was out of focus and the others were unable to record precisely where a chunk of foam from the external fuel tank struck the orbiter. Later analysis found that the foam struck the leading edge of Columbia's left wing, leaving a hole that allowed superhot gases to melt the interior during re-entry two weeks later.

This time NASA will have more than 100 cameras on the ground and in airplanes flying near the launch site. Some of the tracking cameras look more like medium-sized telescopes, with 150-inch lenses. There will also be new cameras mounted on the shuttle and the external tank, looking for any sign of falling debris.

The makers of the external tank, at NASA's Michoud Assembly Facility in New Orleans, have overhauled the way they apply insulating foam in an effort to eliminate the kinds of voids that caused foam to break off during Columbia's ascent. They have removed foam entirely from the area where it detached from Columbia's tank.

It's still unclear exactly what mission managers would choose to do if they detected damage from debris on this flight.

In some non-critical areas of the shuttle, it can withstand gouges three inches across without much harm, experts believe. But in extremely sensitive areas such as the wing's leading edge, a crack as small as 1/20,000th of an inch could cause catastrophic harm on re-entry.

Mission leaders said if the damage were bad enough, they likely would choose to use the space station as a sanctuary rather than try the untested repair techniques. The crew would then have to wait about 40 days for an emergency rescue mission by the shuttle Atlantis, which is being kept ready for such a purpose. The space station has enough supplies to support the shuttle crew for up to 56 days, NASA believes.

Griffin said making all the necessary changes has been "the most difficult job in the history of American spaceflight."
"Obviously it is utterly crucial for NASA, for the space program, for the nation for us to fly a safe mission," Griffin said.

Former NASA historian Alex Roland, a frequent critic of the shuttle program, said the intense attention on this flight may be enough to ensure success.

"This flight is likely to go well, as will the next couple of flights," said Roland, a professor of history at Duke University. "But then, I fear, safety will begin to erode again, as it has done throughout the shuttle's history."

It may be a sign of how far the space program has come that Griffin sounded a lot like Roland on Tuesday. Asked if success on this mission would vindicate the program, Griffin said NASA can't afford vindication.

"The minute we say we're good enough, we start getting bad again," Griffin said. "With 113 launches under our belt, this is still an experimental test flight program."




Shuttle Discovery armed with new safety features

NASA has implemented new safety features and improved existing ones on the shuttle Discovery.

The shuttle's expected launch Wednesday will be the first flight since the 2003 Columbia accident.

During launch

BIPOD FITTING

Helps attach the external tank to the orbiter.

Improvement:

A new copper heating plate under the bipod prevents ice buildup. On Columbia, foam that insulated the bipod fell onto a wing and led to the breakup of the shuttle.

CAMERAS

A total of 107 cameras on the ground and the aircraft will show new angles of the launch and ascent to orbit, making it easier to identify debris from the external tank.

SENSORS

On each wing, 88 sensors were installed to measure acceleration and impact data and take temperatures during the launch phase.


SOLID ROCKET BOOSTERS

Provide main thrust to lift shuttle, then fall into the ocean for reuse.

Improvement: Igniters improved to prevent cracks in solid rocket propellant.

BOLT CATCHERS

Catch severed bolts when boosters separate from the external tank.

Improvement: Two-piece welded design strengthened into a single unit.

LIQUID OXYGEN

FEEDLINE BELLOWS

Joints on the oxygen pipe that allow it to flex.

Improvement: A heater will keep the bellows area at about 40 degrees Fahrenheit to reduce formation of ice.

IN SPACE

ORBITOR BOOM SENSOR SYSTEM

Improvement: A 50-foot extension at the end of a robotic arm can now reach the underside of the orbiter to scan for damage.

CHECKING THE UNDERSIDE

Three days after launch, a new maneuver will allow inspection of the orbiter's protective tiles, which were damaged on Columbia.

International Space Station

Camera

Photos of the belly will be taken to check for damage.

Over the span of about 93 seconds, Discovery will perform a 360-degree rotation.

Photo and boom image courtesy of NASA


Source: NASA

Chicago Tribune


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