Accident Investigation Summary Report: Cessna 182L VH-DSJ, 21 October 1978

This document is the official Aircraft Accident Investigation Summary Report regarding the disappearance of Cessna 182L aircraft VH-DSJ on 21 October 1978. The pilot, Frederick Valentich, was on a private night flight from Moorabbin to King Island. During the flight, Valentich established radio contact with the Melbourne Flight Service Unit and reported encountering an unidentified aircraft in his vicinity. He described the object as having a long shape, metallic and shiny appearance, and a green light. He further reported that the object was hovering and orbiting his aircraft. Following these reports, Valentich stated his engine was running rough and that the object had vanished. Shortly thereafter, all communication with the aircraft ceased. An intensive air, sea, and land search was conducted until 25 October 1978, but no trace of the aircraft or the pilot was ever found. The report includes transcripts of the final radio communications, meteorological data, and various investigator notes. The official conclusion of the investigation is that the reason for the disappearance of the aircraft has not been determined. The document also contains correspondence and internal memos discussing the public and media interest in the case, particularly regarding the pilot's reports of a UFO, and the Bureau's efforts to provide factual information while avoiding speculation.