1982 · A10 autoroute, Trancrainville (Eure-et-Loir) to Artenay and Ormes (Loiret), France

Trancrainville: a green-lit mass over the A10

On the record

Strength C · 5/10 · 2 independent

Evidence 1/4 · Witnesses 2/3 · Backing 2/3

Two on-duty gendarmes over 29 km, an official report and a GEIPAN 'unexplained' finding; no instrument record.

Plausibility High

Score 11 · 7 factors for, 0 against

Two on-duty gendarmes followed a lit mass for 29 km and filed an official report; GEIPAN classed it unexplained after rejecting a helicopter and planets.

See the factors ↓

Unexplained

Witness sketch from gendarmerie procès-verbal 154/1982: 'Schéma explicatif de la vision qu'a eu le Gendarme [name masked] lorsque le phénomène s'est déplacé au dessus des pylônes électriques' — A: masse claire, B: zones éclairées, C: axis on which A and B lay. A10 autoroute, 23 Jan 1982. · Gendarmerie nationale, via CNES/GEIPAN

When23 January 1982, 04:35–04:55

WhereA10 autoroute, Trancrainville (Eure-et-Loir) to Artenay and Ormes (Loiret), France

Backing2 independent

Evidenceofficial records

Before dawn on 23 January 1982 two gendarmes patrolling the A10 autoroute south of Paris saw a grey cone-shaped mass with a sharply bounded pool of green light beneath it, lighting fields, pylons and trees as it moved. It kept pace with their car for 29 km and stopped when they stopped, silent and without a beam. The nearby air base had nothing flying and its radar was off. GEIPAN re-examined it in 2018, rejected a helicopter searchlight and planets, and classed it unexplained.

Evidence, in date order (2)

Jan 1982Gendarmerie (PV 154/1982)official
two patrol officers' signed report PV 154/1982
12 Nov 2018GEIPAN (12 Nov 2018)official
re-investigated and classed it D, unexplained GEIPAN

How plausible · High

Two on-duty gendarmes followed a lit mass for 29 km and filed an official report; GEIPAN classed it unexplained after rejecting a helicopter and planets.

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Access They followed it.
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No gain sought Official report.
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Character record Gendarmes on patrol.
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Checkable details check out Gendarmerie report; GEIPAN class D.
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Restraint Precise description.
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Independent convergence Two officers.

Plausibility weighs how well an account fits where secrecy hides the documents by design, so missing records never count against it. Strength measures what is documented. Assessed 2026-10-23.

Claims

A grey cone-shaped 'masse claire' and a sharply bounded light-green lit zone moved over the ground, lighting fields, pylon tops ('je voyais distinctement les traverses'), hangars and trees; it kept pace with the car for 29 km and stopped when they stopped; no beam, no sound.firsthandOn the recordtwo autoroute-patrol gendarmes (PV 154/1982)

Nothing was airborne from BA 123 Orléans-Bricy, whose radar had been off since the evening before.firsthandOn the recordBA 123, via the gendarmerie report

Where

A10 autoroute, Trancrainville (Eure-et-Loir) to Artenay and Ormes (Loiret), France

48.1°N 1.9°E

Sources

Pictures2

Gendarmerie site photographs (clichés 1–6) taken for PV 154/1982 along the A10: where the object was first seen (PK 61, red arrow), the lit pylons (PK 67), the stopping point of the patrol car (PK 69). Daylight photos of the places, not of the phenomenon.