Sighting in Thonon-les-Bains, September 1, 2014

Between 11:30 and 11:40 pm, a witness was in their bedroom on the fifth floor when they saw a triangular object through the window for a few seconds. It was made up of six white patches that were not dazzling. It moved slowly, at an altitude of less than 50 m. The witness saw it side-on, without making out any "mass", and it then vanished behind a neighbouring building. No sound was heard during the sighting, which the witness found unexpected. No one else reported seeing it.

GEIPAN met the witness for an interview and a reconstruction, which made it possible to narrow down the time; the questionnaire had given between 11 pm and midnight. The features described (gliding appearance, speed, V formation, size) strongly point to a flight of birds. These could have been migrating greylag geese heading towards the eastern end of Lake Geneva, where there is a bird reserve, or local swans disturbed by the noise of a concert that evening. In either case, city lights reflecting off the plumage would explain the appearance described. GEIPAN therefore classified the case as B: probable sighting of birds.