As an Air Force brat who moved five times during his school years, John Denver was a shy, bespectacled introvert who dreamed about three things: flying, space travel, and having friends all over the world. ”Once, when I was about 9,” he remembered in a 1991 interview, ”I was lying in the backyard in Oklahoma, looking up at the stars. All of a sudden, I finally felt connected to something.”

Denver, one of pop music’s biggest hitmakers of the 1970s and a self-described ”global citizen,” long ago connected with a following that stretched as far as the then Soviet Union — where he played as part of a cultural exchange program. But on Oct. 12, the veteran pilot’s fascination with distant horizons took his life, at age 53, when his Long-EZ experimental plane — a homebuilt fiberglass two-seater designed by Burt Rutan — nose-dived into Monterey Bay near Pacific Grove, Calif. At press time, the cause of the crash was unknown, although witnesses say the $50,000 single-engine aircraft, which Denver had bought only the day before, made a popping noise and gave off a puff of smoke before falling from an altitude of 500 feet.

Born in Roswell, N.M., as Henry John Deutschendorf Jr. (his stage name honored his adopted state of Colorado), the singer-songwriter first performed as the lead singer of the Chad Mitchell Trio, then went solo in 1969 after Peter, Paul & Mary scored with his ”Leaving, On a Jet Plane.” Denver’s fourth album, 1971’s Poems, Prayers and Promises, featured his first hit, ”Take Me Home, Country Roads,” a country-flavored, feel-good homage that appealed to both hippies and homemakers. Film producer Jerry Weintraub, Denver’s manager at the time, remembers the remarkable force of that breakthrough smash: ”Everything happened [suddenly]. He sold out every concert venue in the country.”

TV specials (with Frank Sinatra, and the Muppets) and movies (1977’s Oh, God!) followed. As did such ’70s hits as ”Rocky Mountain High,” ”Sunshine on My Shoulders,” ”Annie’s Song,” and ”Thank God I’m a Country Boy” — all sung in the bland but earnest tenor that earned him as much ridicule (”the Ronald Reagan of pop”) as praise. With his ”aw-shucks” persona, benign looks — granny glasses framed by a mop-top hairdo — and sentimental country-folk songs about nature and homespun family values, Denver (whose favorite expression was ”Farrrr out!”) appeared to be the quintessential wholesome performer. ”I don’t want to just entertain people,” he once said. ”I want to touch them.” And that he did, becoming, after Elvis, the biggest-selling solo artist in RCA Records’ history. Denver’s Greatest Hits album, released in 1974, sold more than 10 million copies. In all, of his more than 35 albums, 14 went gold and 8 platinum.

Denver used this popularity to draw attention to many worthy causes and launched the Windstar Foundation in 1976. The nonprofit organization focused its efforts on wildlife conservation and reversing environmental and world-hunger problems.

Still, Denver’s career was not without controversy. In 1975, when the Country Music Association named the outsider its Entertainer of the Year, presenter Charlie Rich took out his lighter and burned the envelope on stage — a show of the old guard’s disgust. As popular tastes changed in the ’80s and Denver lost his commercial clout, an angry, dark personality emerged. Following their 1983 separation, his first wife, Annie Martell, had a stand of trees cut down at the family house in Aspen. Denver retaliated by taking a chain saw to the kitchen table and marital bed. Denver’s second marriage, to Australian actress Cassandra Delaney, ended in an acrimonious 1991 divorce. And he was twice arrested for drunken driving, once in August 1993 and again in August 1994. In fact, when he died, Denver was flying with an invalid pilot’s license, reportedly revoked because of his DWI offenses.

Even Denver’s good deeds could backfire on him. The ardent environmentalist was criticized in 1979 for driving a gas-guzzling Porsche and keeping large fuel tanks on his property during the energy shortage.

”There’s a thing they call the Dark Night of the Soul. I’ve been through that, and I’ve survived it,” he said in 1991. In recent years, through psychotherapy, and despite ongoing troubles with the law, Denver tried to get his life on course. Last year he bought a second home near Carmel, Calif., to be near daughter Jesse Belle, 8, the only child he had with Delaney — and the youngest of his three children. A board member of the National Space Institute, Denver claimed to have inspired the citizens-in-space program that put schoolteacher Christa McAuliffe on the ill-fated Challenger in 1986 (a flight he had fiercely lobbied to be on), and he still dreamed of flying in space.

Denver maintained that his music would come back in vogue, and earlier this year The Best of John Denver Live entered the country charts, his first showing since 1988. At his death, he seemed on the verge of a nostalgia-fueled comeback, with an international tour scheduled for 1998.

But this country boy was never happier than when he was flying. In 1985, Denver participated in a VH-1 promotional contest. ”The key,” remembers RCA Records VP of strategic marketing Michael Omansky, ”was that John would [personally] fly you to one of his concerts in his old plane. Some middle-aged woman with three kids won, and he was perfect with her. His arm wrapped around her the whole time, he just had a blast.”