"It's the journey that matters," the old maxim says, "not the destination."

John Chapman, chief engineer for Space Shuttle Propulsion at NASA's Marshall Space Flight Center in Huntsville, Ala., would debate that idea. It's vital, he says, to have your destination in mind - to know where you're going, and why.

But Chapman acknowledges whether you're road-tripping across America, soaring in a glider held aloft by thermal air currents or working to put the most complex machine ever created - the space shuttle - into Earth's orbit, there's nothing like the journey.

As STS-114: Space Shuttle Return to Flight readies for launch, Chapman is thoroughly immersed in the latter of those journeys. "What's always been most fascinating to me is the simple challenge of flight - persuading a chunk of metal anchored by gravity to fly into the sky," Chapman says. "Look at the solutions humanity has devised over the centuries to get off the ground, to fly through the air, to escape gravity and enter space. Look at the concepts we're developing today. Imagine the possibilities we'll think of tomorrow."

As a leader in the Marshall Center Office of Chief Engineers, part of the Engineering Directorate at Marshall, Chapman is adept at finding solutions, and imagining possibilities. He provides technical recommendations about flight hardware and program issues to the Shuttle Propulsion Program manager. He leads a team of engineering experts, endorsed by NASA Chief Engineer Rex Geveden at NASA Headquarters in Washington, who help solve issues associated with sending the nation's flagship space vehicle back to orbit.

For Chapman, a 25-year NASA veteran who has been involved with the STS-114 since its development and has held nearly every shuttle office manager, deputy manager and business manager post at Marshall, his current job is the culmination of a love affair with flight that reaches back as far as he can remember. An avid model builder even today, he quickly tired in his youth of purchasing tiny jars of model airplane paint, and inquired about bulk supplies of the real thing at a general aviation airport in his hometown of Spartanburg, S.C. "I was looking for model paint," he recalls. "Somehow, I ended up with a job."

He worked at the airport throughout his high school and college years, eventually learning about aircraft mechanics and electrical systems well enough to install hardware in private planes. He spent every spare moment - and most of his earnings - taking flying lessons. He earned his pilot's license on July 15, 1969, the day before Apollo 11 left Earth, carrying the first human beings to walk on the surface of the Moon.

Flying is integral to his life, Chapman says - over the years, he has owned a small plane and two unpowered lightweight gliders. He co-founded the Huntsville Soaring Club for glider enthusiasts, and even proposed to his wife Cindie, a chemist in the Materials and Processes Laboratory at Marshall, while soaring high over the green hills of east Tennessee.

Chapman earned a bachelor's degree in industrial engineering in 1973 from the Georgia Institute of Technology in Atlanta. Between 1973 and 1978, he performed engineering studies on the early development phases of the space shuttle, working first for Northrop Services and then for D.P. Associates, both of Huntsville. He spent the subsequent year field-testing laser-based missile guidance systems for the U.S. Army at Teledyne Brown Engineering in Huntsville, and then joined NASA as an engineer in 1980.

Writing computer programs at the Marshall Center to analyze shuttle propulsion hardware, Chapman was once more drawn to the journey, and to a familiar destination. In 1981, NASA was preparing for STS-1, the shuttle's maiden space voyage. Chapman - who had road-tripped from South Carolina to the Florida Cape with his father 10 years earlier to watch the launch of Apollo 15, and had, with a college roommate, snagged VIP passes to the Apollo 16 launch in 1972 - convinced a group of fellow Marshall engineers they should witness the very first shuttle launch. They borrowed an old motor home from a local car dealer and hit the road.

STS-1 climbed into history, and "carried" Chapman's gang - and the country - along with it.

"I've never forgotten that experience," Chapman says. He also remembers well the close group of friends who made the trip with him, including two young engineers named Sandy Coleman and Jim Kennedy. Today, Coleman is manager of the External Tank Project Office at Marshall, and Kennedy is director of NASA's Kennedy Space Center, Fla.

"We've all come a very long way since then," Chapman says, his words encompassing not just three individuals, but an agency and a nation. "But the journey isn't over yet."

Where to next? "Pick a destination," he says, and points to the sky.