#1: The Disappearance of Frederick Valentich
The disappearance of Frederick Valentich is one of the eeriest mysteries that remains unsolved. On October 21, 1978, the 20-year-old Valentich was piloting a Cessna 182L light aircraft over the Bass Strait en route to King Island, Australia. During the flight, Valentich was in radio communication with Melbourne air traffic control, and he repeatedly made mention of a "strange aircraft hovering on top of me." Right before a strange noise severed the transmission, Valentich went on to say, "It is hovering and it's not an aircraft."