Did Otis redding use drugs to kill himself?

Otis Redding died in a plane crash when he was twenty-seven, and as far as i know he was not an avid drug user. There is something auspicious about the crash; something about a conversation he had with his wife a couple of hours before the plane took off hinted at some foreknowledge of his death. But I think its one of those unanswered and often theorized about questions. Anyway he definitely did not use drugs to kill him self. He was one of the most awesome people ever though. Hope that helps.