[AERO EZY] DE PARIS (75) VERS LISBONNE (PT.11) 21.08.2014

On 21 August 2014 at 12:43, a passenger flying to Lisbon saw a UAP apparently at his aircraft’s altitude. Through the window he initially thought it a bird or drone. As it entered his view more fully, he described a “small black box towards the nose of the aircraft” with trails resembling Japanese fish fins. What he took for propulsion trails drooped rather than extending horizontally. He took phone photographs; only 1 contained the UAP. One account, photographs and sketches of the UAP and scene were collected. GEIPAN considers that he very probably saw an airliner’s contrail. Traffic records show an aircraft crossing his flight’s path left to right, 900 m below (see the investigation report). Sunlight from somewhat behind the witness against a bright background favours a dark-looking trail. A dark cloud in the image under the same conditions supports this interpretation. The relative aircraft movements allow precise reconstruction of the changing position and orientation of the path and trail, but the match occurs 52 seconds after the photograph’s timestamp. This could combine an incorrect phone clock, with automatic radio/network time adjustment disabled or disrupted, and Planefinder tracking inaccuracies. For example, position samples at overly long, unsynchronised intervals could affect reconstructed headings and relative positions. GEIPAN considers coincidence unlikely: if the UAP were something else, the same geometry between the aircraft would occur only tens of seconds later. It would also be difficult to explain why both aircraft and UAP were not in the image, or why the already-alert witness did not react when the aircraft repeated the same scene 52 seconds later. The account has very strong evidential support, with sufficient usable witness information and an analysed photograph. GEIPAN classifies the case A: an airliner’s contrail.