During maneuvers a submarine collides with a surface vessel and drops to the ocean floor. The crew have thirty hours worth of air to get it back to the surface.During maneuvers a submarine collides with a surface vessel and drops to the ocean floor. The crew have thirty hours worth of air to get it back to the surface.During maneuvers a submarine collides with a surface vessel and drops to the ocean floor. The crew have thirty hours worth of air to get it back to the surface.