NASA's shuttle Endeavour is photographed by ISS astronauts during the STS-123 mission in March 2008.
CAPE CANAVERAL -- Independent safety experts say it would be dangerous to fly NASA shuttles beyond 2010, and doing so could lengthen a five-year gap in the nation's ability to launch American astronauts, NASA warns.
But some argue the 6,400 job cuts projected for Kennedy Space Center could be reduced by flying shuttles twice a year until replacement rockets and spaceships are ready.
U.S. Reps. Dave Weldon and Tom Feeney say it could be done by giving NASA about $2 billion more a year to pay for the added shuttle flights and speed up development of spacecraft for missions to the moon and Mars.
What the Republican congressmen propose is possible. The plan could reduce or even eliminate an anticipated five-year gap in NASA human space flight, potentially saving thousands of jobs.
But people inside and outside NASA nonetheless raised financial, practical and safety concerns.
NASA's shuttle program already is winding down. Production lines are shutting down. Suppliers no longer are making critical shuttle parts. Vendors are moving on to other businesses.
Consequently, shuttle operations after the planned retirement date in 2010 might be dangerous and even NASA says it makes no financial sense.
"We could restart things," said John Shannon, a veteran flight director who now oversees the multibillion-dollar program. "You can do anything for a certain amount of money and investment of time, but I think the nation and NASA need to decide if that is really in the best interest of continuing on with what we would like to do in space."
Shannon, other senior agency managers and the White House say it's not. They say the shuttle program must be closed down so NASA can funnel money into the new moon-Mars program.
"I don't mean to sound either cavalier about it or glib," NASA Administrator Mike Griffin said. "We are bringing the shuttle program to a close in 2010. And it will have a very difficult effect on the local work force. If we don't retire in 2010, then we will not have the money to bring a new system online by 2015."
Weldon has other ideas. In December, he introduced a bill to give NASA the money to keep the shuttle fleet flying beyond 2010 and invest an extra $1 billion a year in development of new Ares rockets and Orion spacecraft.
"There is a solution to this," the Republican from Indialantic said. "It's not cost prohibitive. You keep the shuttle flying to 2013. You accelerate the development of the Orion, and plan on deploying it not in 2015, but in 2013 or 2014. You can effectively have a lot of mitigation by doing that."
Money, however, isn't the only issue.
"We are actively shutting down vendors," Shannon said.
Companies that make critical parts such as landing-gear tires and propulsion system valves are mothballing their shuttle business or closing altogether.
Could NASA restart those production lines?
"Yes, we could," Shannon said.
The result likely would be a small delay between NASA's last planned shuttle flight and the next new mission, Shannon said.
Feeney said time is short to make a decision. Others say it's already too late.
"This train has left the station," said retired Navy Adm. Joe Dyer, the chairman of the Aerospace Safety Advisory Panel, which was chartered by Congress after the deadly 1967 Apollo 1 launch pad fire to oversee NASA space flight programs.
The shuttle fleet already is obsolescent, and finding spare parts for systems critical to flight safety -- and the lives of astronauts -- is difficult. Dyer faces a similar dilemma trying to fix one broken part on a navigation system on his sailboat.
"Now, could I go out, with great investment, and get somebody to make me one?" Dyer said. "Yes, but it would be cost prohibitive. It would be slow. It wouldn't be integrated. It's a trivial example, but it makes sense if you scale it up to a larger question like this."
The situation is so bad, some say it would be hazardous to try to keep the shuttle flying.
"To talk about a reverse of strategy, a reverse of direction, over the remaining life of the shuttle would represent a serious safety challenge," Dyer said.
Nonetheless, Feeney said the legislation would provide NASA with enough money to fly shuttles safely while NASA's new craft are being developed.
"Dave's bill is subject to safety being signed off on. It's not like he and I are proposing unsafe additional missions. We would have all the same checks in place," said Feeney, a Republican from Oviedo whose district includes the space center.
"Having said that, any time you're flying something up into the air or into the space, as vehicles get older, there are marginal risks that just occur. Human bodies atrophy and so do machines. So, is it riskier to fly more shuttles? Probably only on the margins."
Dyer said it's like deciding whether to keep repairing an old car, or buy a new one. The chairman of the independent safety group says the U.S. needs new spacecraft.
Even NASA veterans agree.
"Everybody really needs to think real hard about whether that would be the right thing for the nation," said Shannon, a longtime shuttle engineer, experienced flight director and senior manager.
The shuttle was developed in the 1970s to be a do-all vehicle to haul up a space station, planetary probes, commercial satellites and military payloads.
Ten of the last 11 flights will finish the International Space Station. The other is the last service call to Hubble Space Telescope.
"With the completion of the station and the completion of all of the work we would want to do with HST, my opinion is the shuttle's lifetime arc is complete," Shannon said.
The shuttle is amazing, but old and expensive to fly, Shannon said. Once the station is complete, "the shuttle has accomplished its mission, and it's time to move on."
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