Sighting in Trancrainville, January 23, 1982

Between 4:35 and 4:55 in the morning, two motorway-patrol gendarmes were driving along the A10 away from Paris when they noticed a bright, poorly defined mass in the sky and a strongly lit area on the ground. Over a stretch of about thirty kilometres they kept watching the phenomenon, sometimes while driving and sometimes stopped. They heard no particular noise, even during the stop. Several times it disappeared from view and then reappeared. At the very end the bright mass could no longer be seen, but the glow remained to the east, on clumps of trees beside the motorway. One of the witnesses compared the lighting of the landscape to that of a "black light"; they also made out details of a pylon and perceived the glows as motionless.

The gendarmes contacted Orléans air base 123, 7 km from the motorway: no aircraft or helicopter was flying, and the base's radar had been switched off since the previous evening. No employee of Cofiroute, the motorway operator, had noticed anything, and no other witness living along the A10 was found. A resident of Ingré had reported a phenomenon on 17 January to the local press but never went to the police. A local article on 27 January linked the three accounts.

The investigation established that the phenomenon was moving, since it lit various parts of the nearby landscape over a long distance. Astronomical bodies (Jupiter, Saturn and Mars were present) could not explain a "bright mass" or such focused ground lighting. A helicopter with a searchlight, above or within the clouds, would account for the shapeless mass and the absence of navigation lights. However, the cloud base (1,200 and 1,500 m) put it too far from the ground for searchlights of the period, the small lit portion of the pylon implied a very narrow beam, the lighting described does not match a search lamp, and flying above clouds for surveillance makes little sense. No field investigation with the witness was possible given the age of the case. The file sits on the borderline between unexplained and unusable, and it was classified D, unexplained.