On the evening of October 21, 1978, twenty-year-old pilot Frederick Valentich took off from Moorabbin Airport south of Melbourne in a Cessna 182L on a routine training flight to King Island in the Bass Strait. At 7:06 PM, while cruising at 4,500 feet approximately eight miles from Cape Otway, Valentich radioed Melbourne Flight Service that a large unknown aircraft was orbiting 1,000 feet above him. Over the next six minutes — in one of the most chilling transmissions ever recorded — Valentich described a 'long shape' with four bright lights that appeared to be 'toying' with his aircraft, passing within 100 feet and producing bright flashes on its surface.
Melbourne Flight Service repeatedly asked Valentich to identify the aircraft type. He replied that it was 'not an aircraft. It is…' before describing the object as having 'a green light and sort of metallic… it's all shiny on the outside.' He reported engine trouble — the Cessna was 'rough idling and coughing' — and said the object was now hovering directly above him. At 7:12:28 PM, his final transmission was interrupted by a prolonged metallic scraping sound lasting seventeen seconds, after which all contact was lost. Neither Valentich nor the Cessna was ever found, despite a four-day search covering more than 1,000 square miles of Bass Strait.
The Department of Transport's official accident report, released in 1982, listed the cause of the disappearance as 'unknown.' A Victorian civil-engineering student photographed what he said was a UFO off Cape Otway on the same evening as the disappearance; the photograph, analyzed by Australian UFO researcher Bill Chalker, appears to show a light-colored object over the water. On October 23, 1983 — five years to the day after the disappearance — a Cessna engine cowling was recovered from a Flinders Island beach, its partial serial number consistent with Valentich's aircraft. The Valentich disappearance remains one of the most famous aviation UFO cases in history and the only recorded instance of an entire aircraft and pilot vanishing during a live UFO transmission.