Ten passengers are suing JetBlue over a flight during which a pilot had to be physically restrained after screaming about religion and terrorism. They claim the airline was "grossly negligent" in allowing him to fly.
The lawsuit was filed on Wednesday in state Supreme Court in New York, and an early copy was provided to The Associated Press.
The lawsuit contends the airline should have known that Clayton Osbon was unfit to fly.
An airline spokesman did not immediately comment.
Osbon faces federal charges of interfering with a flight crew. Witnesses say he ran screaming through the cabin until passengers wrestled him to the floor.
The plane from New York to Las Vegas on March 27 made an emergency landing in Texas.