Space shuttles blaze path into future

Space shuttle lifts off

April 23, 2001
Web posted at: 9:12 PM EDT (0112 GMT)

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(CNN) -- Nearly 50 years ago, space shuttles were nothing more than a scientist's vision. Now, NASA's space fleet includes four shuttles -- Columbia, Discovery, Endeavour and Atlantis.

The aging vehicles envisioned by rocket scientist Werner Von Braun are expected to remain the sole U.S. manned launch vehicles for years to come, thanks in large part to $100 million in upgrades over the next four years.

NASA's first shuttle, Columbia, which first took flight 20 years ago this month, recently received more than 100 improvements to make it safer and lighter. NASA also enhanced Columbia's heat protection for its wings and altered the orbiter to allow it to dock with the ISS if needed.

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NASA's Space Transportation System (STS), the official name for the shuttle fleet, began as the Von Braun's brainchild in 1952. The scientist envisioned a fleet of huge spacecraft ferrying people to the moon, Mars and space stations that would orbit the Earth and delivering supplies and crews to outposts.

By the time the U.S. spacecraft Apollo landed on the moon in 1969, the United States was deeply involved in the costly Vietnam conflict. All that remained of Von Braun's grandiose plans was the shuttle idea.

The shuttle was touted and designed as a reliable, cost-effective space truck that could handle a military and a commercial role, CNN space correspondent Miles O'Brien reported. It would be like a space airliner, NASA claimed, dispatched every two weeks to bring satellites to and from low Earth orbit. And it would pay for itself.

The Air Force wanted a cheaper way to send military and spy satellites to space, so NASA designed a vehicle that would meet military specifications for cargo weight, size and performance.

The explosion of the shuttle Challenger during takeoff in 1986 nixed the commercial aspect of NASA's plans, and the military decided not to put its satellites on board either.

Once again, the shuttle was a ship without a port. NASA used its STS to deploy and service telescopes and carry interplanetary probes. It was not close to what Von Braun envisioned.

But the creation of the International Space Station with Russia and other nations pumped purpose into the missionless machine. When the shuttle Atlantis docked at Space Station Mir in July 1995, the Space Transportation System suddenly had a point.

Until then, NASA had considered retiring and replacing the shuttles with a new generation of space vehicles. Now NASA wants to upgrade the shuttle fleet to allow the ships to carry needed supplies and people to the International Space Station.

Despite the planned improvements, NASA still is developing a new generation of manned orbiters that will be safer and more cost effective.

At a cost of about $400 million per launch, the payload cost runs about $10,000 a pound. New spacecraft would include "air-breathing" rocket engines that reduce the vehicle's fuel weight at launch by inhaling oxygen from the air during liftoff.

Other plans include magnetic levitating devices that could be used to launch the orbiters, a thermal heating system that could repair itself by foaming up and replacing lost material and a solar propulsion system and pulse detonation engines.

Another feature of the new launch vehicles would allow the crew to abort a takeoff if something goes wrong during launch. Now, the solid rocket boosters can't stop after liftoff, and there is a one in 450 chance of disaster every time a shuttle goes up, said Art Stephenson, director of NASA's Marshall Space Flight Center.

But NASA has suffered numerous technological pitfalls in developing the X-series vehicles, a fleet of prototype shuttle replacements. And Stephenson acknowledges that some advances could take 40 years to come to fruition, if ever. But Stephenson said he hopes NASA can start using some of them within a decade's time.

The magnetic levitating system, Stephenson said, "is a technology we think can be demonstrated in five years, if we get the funding we are talking about, and be operational in 10 years."

CNN's Miles O'Brien and Richard Stenger contributed to this report.

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