Sighting in Guérard, May 12, 1992

At around 10:30 p.m., a witness on the first floor of their home noticed a yellow spot of light in the sky. A second witness joined them, and together they watched the object, which seemed to lengthen and then slowly followed a rising path. In a final phase it changed direction, leaving a yellow trail behind it, and gradually moved away. No sound was heard during the sighting. Both accounts were taken down by the gendarmerie, which carried out an investigation. At the start of their statement, the first witness also mentioned two earlier sightings.

This case, originally classified D, was re-examined by the GEIPAN. According to the analysis, the object was an aircraft. It was first seen head-on with its landing lights on, which explains why it looked motionless or slow-moving. It then apparently turned while climbing to an air layer where a condensation trail could form, and was seen more from the side, giving the impression of a sudden acceleration. The trail, very short at first, was probably taken to be part of the aircraft itself, hence the impression of an object that was lengthening; the witnesses told the two apart once the trail stretched out after the turn. The aircraft may have taken off at night from Auxerre-Branches, flown north and then turned northeast. The lack of noise does not rule this out: at long range, depending on the wind, the sound of an aircraft may not be heard. The investigators also tried to determine whether the trail could still have been lit by the sun, which was 10° below the horizon, but the uncertainties were too great to conclude. The GEIPAN classified the case B: probable sighting of an aircraft.