VENTURA, Calif. — A plane registered to Oscar-winning “Titanic” composer James Horner has crashed in Southern California, but the identity of the one person who died has not been released. Jay Cooper, an attorney for Horner, said the plane was one of several owned by the 61-year-old composer, and that no one has heard from him since the crash. “It was his plane and if he wasn’t in it, he would’ve called,” Cooper said Monday night. The Associated Press has not confirmed Horner’s death. The Hollywood Reporter cited Sylvia Patrycja, who it says is identified on Horner’s film music page as his assistant in confirming his death.