Steve Snowden/Getty ImagesPaul Kantner, the singer, guitarist and songwriter who co-founded the pioneering San Francisco psychedelic rock band the Jefferson Airplane and its spinoff group the Jefferson Starship, died Thursday at the age of 74.

Michael Gaiman, who’d managed Kantner for 25 years, confirms to ABC Radio that the cause of death was multiple organ failure, and that Kantner had suffered a heart attack this week.

Kantner formed the Jefferson Airplane in 1965 with his friend, singer Marty Balin, and the band’s initial lineup also included singer Signe Anderson, guitarist Jorma Kaukonen, bassist Jack Casady and drummer Skip Spence.  After releasing its debut album, Jefferson Airplane Takes Off, in 1965, singer Grace Slick was brought in to replace Anderson and Spencer Dryden took over for Spence. This lineup of the group went on to record the group’s landmark 1967 record, Surrealistic Pillow, which featured the band’s only top 10 hits — “Somebody to Love” and “White Rabbit.”

Jefferson Airplane was the first band from the San Francisco scene to score mainstream success.  They also performed at the three most legendary U.S. rock festivals of the ’60s: Monterey Pop in 1967, Woodstock in 1969 and Altamont in 1969.

Kantner contributed his voice and guitar to many of the group’s songs, and wrote or co-wrote such tunes as “Today,” “Martha,” “Crown of Creation,” “We Can Be Together” and “Volunteers.” He also co-wrote “Wooden Ships” with David Crosby and Stephen Stills, a song recorded by both the Airplane and Crosby, Stills & Nash. In 1971, Kantner fathered a daughter with Slick named China.

After the Jefferson Airplane broke up in 1972, Kantner formed a new group with Slick called the Jefferson Starship, which Balin eventually joined. That group released a series of pop and rock hits throughout the 1970s and into the ’80s. Kantner exited the band in the mid-’80s over the artistic direction of the group, and then formed the short-lived KBC Band with Balin and Casady.

The Jefferson Airplane reunited in 1989 for a new album and tour, and a few years later Kantner re-formed the Jefferson Starship with a shifting lineup of musicians that included Balin, Casady and founding Jefferson Starship bassist David Freiberg. In 1996, Kantner was inducted into the Rock and Roll Hall of Fame as a member of the Jefferson Airplane.

In March of 2015, Kantner suffered a heart attack, but he returned to the Jefferson Starship after a period of recovery and continued to perform with the band until his death.

Marty Balin shared the following statement regarding Kanter’s death on Facebook Thursday night: “So many memories rushing through my mind now. So many moments that he and I opened new worlds. He was the first guy I picked for the band and he was the first guy who taught me how to roll a joint. And although I know he liked to play the devil’s advocate, I am sure he has earned his wings now’. Sai Ram ‘Go with God’. #paulkanter #jeffersonairplane #thejeffersonairplane.”

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Source: Classic Rock News