Paul Kantner, a founding member of San Francisco rockers Jefferson Airplane, died today at 74 after he suffered a heart attack this week. The San Francisco Chronicle reported that the cause of death is multiple organ failure and septic shock as confirmed by Kantner’s publicist.

Kantner and Jefferson Airplane, whose classic lineup also consisted of Marty Balin, Jack Casady, Jorma Kaukonen, Grace Slick and Spencer Dryden, were a staple of the late-‘60s San Francisco scene and the psychedelic rock scene overall, playing at legendary festivals like Monterey, Woodstock and Altamont. Together, the group offered up classic songs like “Somebody to Love,” “White Rabbit.” Kantner himself aided in the songwriting, collaborating with Balin on tunes like “Today,” “Young Girl Sunday Blues” and “Volunteers.”

Kantner, along with Slick, were also part of Jefferson Starship after the Airplane split up. While the Starship gained commercial success, Kantner left the group in 1984. Along with the rest of the group’s classic lineup, Kantner took part in a brief Jefferson Airplane reunion in 1989 and formed his own Jefferson Starship—The Next Generation in the early ’90s. (Airplane alums such as Marty Balin and Jack Casady were members of the group over the years). After dropping The Next Generation tag from his band name, Kantner continued to tour with Jefferson Starship into this year, and he was inducted into the Rock and Roll Hall of Fame in 1996 for his work with Jefferson Airplane. He is the only musician to take part in every band under the “Jefferson” banner throughout the past 50 years.

He is survived by his daughter with Slick, China Isler, and his two songs, Gareth and Alexander.

“The Airplane was an amazing aggregate of personalities and talent,” Kaukonen wrote today. “That we could all coexist in the same room was amazing. That we could function together and make the lasting art that we did was nothing short of a miracle. In my opinion Paul was the catalyst that made the alchemy happen.” Read more thoughts from Kaukonen and Balin here.