A basic training film made by the U.S. Navy, "Co-ordinated Anti-Submarine Warfare Part I Why?" discusses how surface ships, aircraft and submarines work together to unravel the submarine threat. The film begins with images of a Soviet submarine operating on the surface, and then explains basic anti-submarine techniques. This includes a discussion of both passive and active sonar, and shows how sonobuoys and other technology are deployed to locate enemy submarines. Features footage... Topic: U.S. Navy training film.