Seventies folk-pop singer John Denver died in a single-engine plane crash off the coast of northern California Sunday afternoon, according to the Associated Press. The writer of such hits as "Take Me Home, Country Roads," "Rocky Mountain High" and "Thank God I'm a Country Boy" was flying what was considered an "experimental" aircraft when the plane unexpectedly fell 500 feet into Monterey Bay and broke into several parts. Denver was a licensed pilot, reared in an Air Force family. He was 53.

The singer, born John Henry Deutchendorf in Roswell, New Mexico, first came to prominence during the second half of the '60s when he joined the Chad Mitchell Trio. His song "Leaving on a Jet Plane" became a #1 hit for Peter, Paul and Mary in 1969. In the 1970s, he racked up a string of light, country-flavored hits, including "Annie's Song," "Rocky Mountain High" and "Sunshine on My Shoulders." His Greatest Hits album sold 10 million copies around the globe, while 20 of Denver's albums went gold (500,000 copies sold) in the United States.

Although the '80s and '90s saw Denver's drop off the charts, he continued to remain active in liberal causes. He was known as a staunch environmental advocate, and in 1987 he traveled to the Soviet Union to perform a benefit for victims of the Chernobyl nuclear power plant disaster. Seven years later, he became the first American musician to perform in Vietnam since the end of the war there. In 1993, he was awarded the Albert Schweitzer Music Award, for lifetime humanitarianism. -- Chris Nelson [Mon., Oct. 13, 1997, 9 a.m. PDT]