SirChaz

NASA cruises through flight countdown


By Marcia Dunn, AP Aerospace Writer | July 11, 2005

CAPE CANAVERAL, Fla. --With no major technical snags and a fair weather forecast, NASA cruised through the countdown Monday for its first space shuttle flight in 2 1/2 years. One manager described the excitement by saying, "It's like Christmas is coming."

Discovery and its crew of seven are set to blast off Wednesday in front of a multitude of NASA cameras watching for the kind of flying debris that doomed Columbia in 2003. The shuttle's destination: the international space station.

Shuttle program manager Bill Parsons had this message for the two space station astronauts awaiting the shuttle's arrival: "It's probably time for them to get ready. I think we're on our way."

Typical summer-afternoon thunderstorms were in the forecast, but shuttle meteorologists put the chances of an on-time launch at 70 percent.

Monday's two-days-before launch readiness meeting lasted 3 1/2 hours, considerably longer than was customary before Columbia took off on its final, fatally flawed mission. Deputy shuttle program manager Wayne Hale said there was "spirited" discussion, and dissenting opinions were heard over a few technical issues.

But he said the vigorous discussion was "just a new symbol of the openness" at NASA since the Columbia disaster. Investigators blamed the tragedy in part on the space agency's "broken safety culture," or a tendency to downplay risks and discourage engineers from speaking up.

Hale -- who likened the anticipation to waiting for Christmas -- said that spaceflight is inherently risky. But he said: "There comes a point in time when you decide that we have reached an acceptable level of risk to go carry out the mission that we have, and I think that we are at that point."

He added: "Now's the time to go fly."

Discovery is outfitted with a redesigned external fuel tank, and has dozens of motion and temperature sensors embedded in the wings to detect any blows from fuel-tank foam insulation or other debris. The spaceship also holds a brand-new laser-tipped 50-foot boom that will be used by the astronauts to survey the wings and nose cap for any cracks or holes.

More than 100 cameras on the ground and aboard two planes will focus on Discovery as it climbs toward orbit, and spy satellites as well as astronauts on both the shuttle and the international space station will take their own pictures. The shuttle will spend more than a week at the space station, replenishing its cupboards and repairing broken equipment both inside and out.

NASA failed to request spy satellite pictures of Columbia in orbit, and dismissed the foam that hit the shuttle at liftoff as trivial. The resulting hole in the left wing caused the spacecraft to break apart during re-entry on Feb. 1, 2003, killing all seven astronauts.

The Columbia accident investigators insisted that NASA rely on spy satellite pictures on all future shuttle flights, and that the space agency have at least three good, useful views of the shuttle on its way to space.

Stephanie Stilson, a NASA manager who oversaw Discovery's safety modifications, said that after numerous setbacks and delays, the countdown "leaves me with goose bumps every time I think about it."

"Along the way so many times, we had our hopes up just to find out that we would have to delay for numerous reasons," she said. "We had, of course, hardware problems. We had new modifications that had to be installed that we weren't aware of at the beginning of the flow. We had hurricanes. So a lot of things had been discouraging along the way."

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On the Net:

NASA: http://spaceflight.nasa.gov

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“votes are collared under democracy, not by talking sense but by talking nonsense.” ~H. L. Mencken

SirChaz

Experts: Aging Shuttle Fleet Poses Danger

By JEFF DONN
The Associated Press
Saturday, July 16, 2005; 4:03 PM

CAPE CANAVERAL, Fla. -- Maybe NASA's managers still view the shuttle as the Cadillac of space technology, but they sometimes make it sound as if it were a cranky old Ford with a few too many miles on it.

Deputy shuttle manager Wayne Hale says its recent on-again, off-again electronics problem "reminds me of an old truck I own."

Delays for safety improvements have repeatedly thwarted the shuttle's comeback from the Columbia catastrophe 2 1/2 years ago. But aging components could eventually add their own setbacks and risks to flying as the shuttles near retirement in just five years, according to authorities on space travel.

"If I have any worries at all, it's a few years from now, down the road, when the hardware gets older," said Bob Sieck, a former shuttle launch director and NASA safety adviser.

Designed in the 1970s, the shuttle was meant to advance space travel by several giants leaps. It was to be named the Space Clipper, in a reference to the speedy American clipper ship that expanded the possibilities of sea travel in the 19th century.

The shuttle would be the first vehicle to travel back and forth to space. Its comparatively comfy quarters for crew and garage-like cargo bay made the old space capsules feel like claustrophobic sardine tins. The shuttle would make trips to space much more routine, more like commercial flying. It would potentially be the first step in putting space within the reach of ordinary business and tourism.

In the end, the shuttle took on its more prosaic name and accomplished more prosaic functions _ but still is a marvel of sorts. It has deployed satellites, maintained the Hubble Space Telescope, and helped to build the international space station. It has kept Americans in space while they tried to decide on their next destination after the moon.

But the shuttle's end has come in sight. "The clipper ships were the peak of the sailing art, and we don't see those either. I think there's a lesson to be learned from that," NASA Administrator Michael Griffin said last week at Kennedy Space Center.

Columbia flew the first shuttle mission in 1981. It was quickly followed in the next several years by the shuttles Challenger, Discovery and Atlantis. Challenger was obliterated in its 1986 disaster, and Columbia was lost in 2003, killing a total of 14 astronauts in the two accidents. NASA is left with Discovery and Atlantis, ages 20 and 21, as well as the 13-year-old Endeavour that replaced Challenger.

People are young at 20, but electronics are well into maturity by then _ if not beyond. "I wonder whether I could find a single electronics box in my house that's 25 years old and still works. I don't think I can. It's the same thing with the orbiter," the NASA administrator said of a recent shuttle part breakdown.

It is ostensibly a similar problem in a fuel sensor that ruined the shuttle's long-awaited return to flight last week. A manager said _ and not in jest _ that they would first try to wiggle the wires. However, NASA did enlist a cross-country team of hundreds of engineers to figure out what went wrong. The agency has indefinitely delayed the launch.

John Muratore, a NASA systems manager working on the sensor fault, acknowledged the problem of fathoming glitches in aging shuttles. "There isn't a lot of experience with aging, with having spacecraft that have had this long an operational life," he said.

To troubleshooters, the shuttle presents a labyrinth of wires, cables, signal boxes, transistors, diodes and capacitors _ one of the world's most sophisticated machines. It enfolds 230 miles of wiring and 1,060 valves alone, and about 2.5 million parts in all.

Shuttle parts are regularly inspected and often replaced, especially ones viewed as critical to protect crew, craft and cargo. The shuttle replaces its external fuel tank with each flight.

"We have replaced much of the hardware. Some of the systems ... are more reliable than they were at the beginning of the program," said Michael Wetmore, NASA's director of shuttle processing. However, he acknowledged that some systems might show "a slowly increasing rate" of problems in the future.

Rattled by 180 million horsepower of thrust at liftoff, many shuttle parts do wear over time. They undergo extreme cold and heat during a flight. Some get nicked during maintenance, and others get chafed. Wires slowly crumble.

"We have learned that parts do need replacing more frequently than we would like," said Randy Avera, a former NASA engineer who helped develop the shuttle inspection program.

He said NASA should expand inspection and maintenance to keep the maturing shuttle fleet both efficient and safe. He said that will cost more money and possibly keep shuttles on the ground even longer. He fears the agency won't act quickly enough.

Kathryn Thornton, a former astronaut who has advised NASA on returning to flight, said she worries the agency won't be willing to keep the spacecraft in the best flying condition as it approaches retirement. "You have to keep the people and expertise around to the last flight," she said.

U.S. Sen. Kay Bailey Hutchison, R-Texas, who chairs the Subcommittee on Science and Space, said she believes Congress will provide the money needed to keep the shuttle running safely until its successor is developed. "I think the key is not whether they are getting too old, but whether they are maintaining them properly," she said.

After all, she said, each was designed for 100 trips into space. Discovery, the dean of the fleet, has launched only 30 times. The entire fleet has gone up only 113 times. Its designers envisioned a lot more wear but over a much shorter time. The original design called for a 10-year life span.
© 2005 The Associated Press

__________________
“votes are collared under democracy, not by talking sense but by talking nonsense.” ~H. L. Mencken