Updated

Friday marks the 40th anniversary of one of classic rock music’s greatest tragedies — the crash of the plane carrying the Southern band Lynyrd Skynyrd.

Killed in the Oct. 20, 1977 crash were founder and lead singer Ronnie Van Zant, guitarist Steve Gaines and his sister, singer Cassie Gaines and members of the plane crew.

Other members of the band survived with various injuries – and eventually reformed the band, with Van Zant’s younger brother, Johnny, as lead singer. (Another brother, Donnie, has long been a member of the band .38 Special.)

The Jacksonville, Fla., band – known primarily for the songs “Freebird” and “Sweet Home Alabama” -- still tours today under the Skynyrd name.

The name was inspired by Leonard Skinner, who was a high school teacher of several band members.

But guitarist Gary Rossington is the only remaining member from the band’s classic lineup. Past members Allen Collins, Billy Powell and Leon Wilkeson have died, and drummer Artimus Pyle is estranged from his former bandmates.

The crash occurred when Lynyrd Skynyrd were nearing the peak of their success. So fans have long wondered what might have happened if the plane crash had never occurred.

The plane was to carry the band from Greenville, S.C., to Baton Rouge, La., but it crashed along the way in Mississippi, the Florida Times-Union reported.

“I think if Lynyrd Skynyrd had lasted, they would have become one of the foundations of American rock bands, much like Tom Petty and the Heartbreakers or Bruce Springsteen and the E Street Band,” music writer Bill Bentley told the newspaper.

In recent years, the band has recorded new albums and toured on the “classic rock” circuit, playing the old favorites as well as some more recent songs.

This year it has been involved in a legal dispute over a documentary film based on the memories of Pyle, the estranged member. In August, a judge ruled in favor of Rossington and Van Zant’s widow, who wanted the film’s distribution halted.

Lynyrd Skynyrd was inducted in the Rock and Roll Hall of Fame in 2014.

The Associated Press contributed to this story.