Nine years ago this month John W. Young was hot-rodding through the dusty desert of the Plaine of Descartes, and had a problem any kid with a jalopy can understand.

His fender fell off.

Most car-happy kids, grown-up or not, would just drive on. But Young's joyride was a bit unusual. The Plain of Descartes is on the moon, and Young was revving his modified dune buggy through unexplored volcanic hills and the fine, inches-deep lunar dust.

Back on the home planet, 250,000 miles away, in Houston, Young's bosses figured the Apollo 16 explorations of the lunar rover were over. "That baby was throwing so much dust on him and Charlie Duke [the other astronaut] they looked like coal miners," said Rocco Petrone, the Apollo program director.

Young, commander of America's latest Buck Rogers machine, the space shuttle, is not one to be so easily deterred. While the space agency's hottest earth-bound troubleshooters scratched their heads in dismay, Young bent his cardboard lunar map into a makeshift fender and went on with his chores.

National Aeronautics and Space Administration officials say it's that kind of ingenuity, the kind that can fix a multimillion-dollar machine with a piece of cardboard, that makes Young almost the perfect commander for the maiden flight of the shuttle.

Young, a 50-year-old with a body honed by relenless physical training to keep him apace of men half his age, has been in space four times. Until this week he had spent 533 hours and 33 minutes beyond Earth's compelling tug. He has been an active astronaut longer than any other American.

His traveling companion is a rookie, 43-year-old Robert L. Crippen, a Texan whose radio-warped outerspace drawl may be indistinguishable from Young's at times during the 54-hour shuttle flight. But the focus will be on Young, a California-born former Navy test pilot who picked up his soft, understated drawl when he moved as a youngster to nearby Orlando.

As the world listens this weekend to the gosh-gee-whiz descriptions of Earth's deceptive serenity from the 170-mile-high orbit of the space shuttle, little poetry will be heard.

These men are mechanics, technicians, improvisers, daredevil test pilots, not poets. For the 20 years of the ultimate adventure of space travel, the vicarious yearnings of the earthbound masses left behind have been satisfied by photographs, not words.

Young, the veteran, may have won the prize for pedestrian descriptions when he took Apollo 10 to the moon, man's fourth visit there. "I'm telling you, this place is something," the cool test pilot radioed home.

Crippen, a Navy captain, a unlikely to spice up the space lingo. Once, when he was asked about the romance of reaching out to the stars like a modern Columbus, he deferred to his commander, saving Young was the philosopher aboard the craft. It was like saying Farrah Fawcett was the actress in "Charlie's Angels."

But it is too simple to write off the astronauts as super-dull technicians, just as it was oversimplifying to portry them as super heroes.

The stereotyping bothers Young and most of his colleagues. "There's no two of us alike," he said."You know, they always tend to lump astronauts in the same bunch, the way they say old people all think about the same things and worry about the same things. But there aren't two old people alike, and there aren't two astronauts alike, either."

In some ways, Young and Crippen symbolize the differences. Young is divorced and remarried to a an aerospace-company secretary. Crippen has been married more than 20 years to his wife, Virginia.

Both run miles every day to stay in shape. Crippen is almost movie-star handsome, as well as athletic. Young is a superb physical specimen, but described as almost clumsy, to much so that the space agency once prohibited him from surfing, one of his favorite sports, because he might injure himself.

The 108 American astronausts have become, among other things, senators and complete societal dropouts, corporate chairmen and real-estate hustlers brushing up against the edges of the law, teachers and beer-commercial touts.

Some are divorced, and are seen now at the cape with their arms draped around lovelies half their age. Others are happily married, putting kids through college and looking forward to silver wedding anniversaries. Eight are dead.

Of the first two men on the moon, Neil Armstrong retreated quickly from history's spotlight and into the protective environment of a Midwestern college professorship. He didn't come here for the shuttle launch, where the media mob would have stormed him again.

His lunar colleague, Edwin E. (Buzz) Aldrin Jr., struggled with the same endless confetti shower, fought a bout with alcoholism and confined himself briefly in a psychiatric ward. He isn't here either.

None found his cover so stripped bare by the very technology that got him there as Armstrong. The medical sensors attached to him revealed that his heart rate was 160 beats a minute at touchdown, a rate more than twice his normal rate and one that humanized him as a mere mortel who knew fear, too.

Young, the commander of the Columbia, is a lot like that, even if he is prone to a jet-jockey's occasional hijinks. On his first trip into space, aboard Gemini 3 with Virgil (Gus) Grissom in 1965, Young smuggled a corned-beef sandwich into space because he'd heard the squish-bag dinner fare was downright lousy. NASA, with visions of weightless beef fat glunking up its sophisticated hardware, almost had fits. A Senate committee even looked into it.

Two years later Young's space buddy, Grissom, was burned to death in the flash fire aboard Apollo 1 that killed three astronauts in a ground test here.

Young was as close to Grissom as anyone in the young and new astronaut corps. For months he turned inward, avoided the press and outsiders. There were rumors that he was seen late at night on dark roads outside Houston, racing his automobile at 100 mph for therapy, just to drive the hurt out of his system.

But long after the other early astronauts have left the space program to enter the Senate or do beer commercials, to contend each in his own way with the smothering weight of heroes' confetti, John Young remains in the corps. It's as if he has a debt, one that television commercials or politics or the executive suite could never repay.

No one will speak to that, of course. But NASA, in a touch of unlikely governmental symbolism of its own, has put a corned-beef sandwich aboard the space shuttle Columbia -- officially, this time.