http://www.al.com/news/huntsville/Oct2000/22-e13344.html

Rocket engineers and scientists at Marshall Space Flight Center are working on a technology initiative that many in the aerospace industry hope will help lower the cost of sending payloads - machine and human - into space.

In the cubicles and labs at Marshall, men and women are looking at improving rocket engines, magnetic rail systems and nuclear reactors to boost rockets and payloads into orbit. It's part of a planned $30 million propulsion lab that NASA hopes will improve launch safety, cut the cost of space travel and improve the reliability of spacecraft.

''Safety, affordability and reliability - it's all related. You're not going to get a better vehicle with lower costs if it's unsafe,'' said Dr. John Rogacki, Marshall's director of space transportation. ''Nobody's going to use a vehicle that has a poor safety track record.''

It's not easy beating gravity. Engineers can develop and produce working models, but the fact is that developing the next propulsion system will be a long process. Rogacki said it would take nearly 15 years before engineers develop a replacement for the space shuttle, 25 years before they build a launch vehicle with engines as efficient as those on jets we fly today, and probably 40 years before space flight becomes as common as air travel.

''Very, very hard problems of physics exist when it comes to developing engines that can develop enough energy to push large payloads into space,'' Rogacki said.

Engineers are looking to a host of seemingly wild concepts to propel spacecraft.

Tracks lined with magnets could push vehicles almost to the speed of sound, about 700 mph, giving them a boost just before liftoff.

Nuclear engines could be used to expand gas, performing essentially the same function that chemical reactions do in today's rockets, and propel spacecraft into space.

The limiting factors are the same as those that affect the chemical rockets that have pushed astronauts to the moon and back and put thousands of satellites into orbit: Too much gravity and not enough money conspire against the rocket scientists.

Estimated cost to develop and build a new, reusable space vehicle: $8 billion.

''It's just too much for industry to undertake without a significant contribution from government,'' Rogacki said. ''Stockholders just won't approve it, and industry probably isn't going to put in but about half that amount.''

That's why NASA is looking to work with private companies in their gamble to develop new propulsion technologies. More than 400 aerospace leaders ventured to Marshall last week to see if their companies could land propulsion development contracts.

Marshall Director Art Stephenson draws the comparison to venture capitalists who gamble on startups.

''They spread their money out there and are lucky if they get a return on one out of 20 investments,'' Stephenson said. ''If we invest in 20-30 new technologies and one comes back, then we've developed what will not only get us into orbit, but what will take us to other worlds.''