Sighting in Siorac-en-Périgord, August 17, 2014

One evening, around sunset, the witness noticed a straight, bright line in the sky, followed by several others moving across it. They filmed and photographed what they saw.

The investigation identified these lines as contrails from airliners, a typical appearance when they are viewed close to the horizon at that time of day. Visibility was excellent that day, so the witness could see aircraft farther away than usual. At that distance, contrails look shorter and slower, and they appear more or less vertical when the aircraft is heading away from or toward the witness. Whether a contrail appears or disappears can also depend on the weather conditions at the aircraft's own location.

The photos leave no doubt about the nature of the phenomenon. The witness was also looking in a direction with very heavy air traffic, especially on a Sunday evening in summer. GEIPAN classified the case as A: contrails from airliners.