Thread: Redesign Is Seen for Next Craft, NASA Aides Say

Redesign Is Seen for Next Craft, NASA Aides Say

By WILLIAM J. BROAD
Published: August 2, 2005

For its next generation of space vehicles, NASA has decided to abandon the design principles that went into the aging space shuttle, agency officials and private experts say.



The Return to Space
With so much riding on the Discovery launching, critical changes have been made to the shuttle. Also, a look back at the history of the shuttle program.

Instead, they say, the new vehicles will rearrange the shuttle's components into a safer, more powerful family of traditional rockets.

The plan would separate the jobs of hauling people and cargo into orbit and would put the payloads on top of the rockets - as far as possible from the dangers of firing engines and falling debris, which were responsible for the accidents that destroyed the shuttle Challenger in 1986 and the Columbia in 2003.

By making the rockets from shuttle parts, the new plan would draw on the shuttle's existing network of thousands of contractors and technologies, in theory speeding its completion and lowering its price.

"The existing components offer us huge cost advantages as opposed to starting from a clean sheet of paper," the new administrator of NASA, Michael D. Griffin, told reporters on Friday.

The plan, whose origins go back two and a half years, is emerging at a time when it may help deflect attention from the current troubles of the shuttle fleet.

The Discovery's astronauts are to make a spacewalk tomorrow to fix a potentially hazardous problem with cloth filler on its belly.

Future missions have been indefinitely suspended while NASA tries to solve the persistent shedding of foam from the external fuel tank at liftoff.

The plan for new vehicles is to be formally unveiled this month. Its outlines were gleaned from interviews and reviews of trade reports, Congressional testimony and official statements. Some details were reported on Sunday in The Orlando Sentinel.

On Friday, Dr. Griffin emphasized the plan's safety, telling reporters that the new generation of rockets would have their payloads up high to avoid the kinds of dangers that doomed the Columbia two and a half years ago and threatened the Discovery last week when insulating foam broke off its fuel tank shortly after liftoff.

"As long as we put the crew and the valuable cargo up above wherever the tanks are, we don't care what they shed," he said. "They can have dandruff all day long."

Congress would have to approve the initiative, and many questions remain. John E. Pike, the director of GlobalSecurity.org, a private Washington research group on military and space topics, said he wondered how NASA could remain within its budget while continuing to pay billions of dollars for the shuttle and building a new generation of rockets and capsules.

Alex Roland, a former historian of the National Aeronautics and Space Administration who now teaches at Duke University and is a frequent critic of the space program, said the plan had "the aroma of a quick and dirty solution to a big problem."

But supporters say it will let astronauts move expeditiously back into the business of exploration rather than endlessly circling the home planet, and do so fairly quickly.

"The shuttle is not a lemon," Scott J. Horowitz, an aerospace engineer and former astronaut who helped develop the new plan, said in an interview. "It's just too complicated. I know from flying it four times. It's an amazing engineering feat. But there's a better way."

Dr. Horowitz was one of a small group of astronauts, shaken by the Columbia disaster, who took it upon themselves in 2003 to come up with a safer approach to exploring space. Their effort, conceived while they were in Lufkin, Tex., helping search for shuttle wreckage, became part of the NASA program to design a successor to the shuttle fleet.

The three remaining shuttles are to be retired by 2010 under the Bush administration's plan for space exploration, which is intended to return humans to the Moon and eventually Mars.

The new vehicles would sidestep the foam threat altogether, and its supporters say they would have other advantages as well. The larger of the vehicles, for lifting heavy cargoes but not people, would be some 350 feet tall, rivaling the Saturn 5 rockets that sent astronauts to the Moon.

The smaller one, for carrying people, would still dwarf the shuttle, which stands 184 feet high with its attached rockets and fuel tank.

The spaceships would no longer look like airplanes. Their payloads, whether humans or cargo, would ride in capsules at the top rather than alongside the fuel tank - standard practice until the shuttle era. Rather than gliding back to Earth, they would deploy parachutes and land on the ground in the Western United States.

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http://www.nytimes.com/2005/08/02/sc...rssnyt&emc=rss