Frederick Valentich disappeared from Melbourne air traffic control over Bass Strait in the Indian Ocean following contact with an unidentified aircraft.
Frederick Valentich was an Australian pilot who disappeared while on a 125-nautical-mile (232 km) training flight in a Cessna 182L light aircraft, registered VH-DSJ, over Bass Strait on the evening of Saturday 21 October 1978. Described as a "flying saucer enthusiast", twenty-year-old Valentich informed Melbourne air traffic control that he was being accompanied by an aircraft about 1,000 feet (300 m) above him and that his engine had begun running roughly, before finally reporting, "It's not an aircraft." 
