GEIPAN Case 1982-01-00913 — TRANCRAINVILLE (28) 23.01.1982

Brief

On 23 January 1982 at approximately 04:35, two gendarmes patrolling the A10 motorway near Trancrainville observed an undefined aerial mass — described by one witness as cone-shaped and gray-white, by the other as a formless clear mass — that illuminated large swaths of terrain, high-tension pylons, and farm structures across roughly 29 km with no visible connecting beam and no audible sound. The BA123 Orléans-Bricy air base confirmed no aircraft were airborne and its ground radar had been offline since the previous evening. GEIPAN's 2018 technical re-examination ruled out the helicopter-with-searchlight hypothesis on the grounds that no searchlight of sufficient power existed in 1982; the Spectrolab SX-16, first capable of illuminating terrain from 1500 m altitude, was not deployed on French civil or military helicopters until 2002. The case retains its original D (unexplained) classification.

Metadata

Agency

GEIPAN / CNES

Release

2007-03-22

Type

PDF • .pdf

Length

27 pages

Classification

D (GEIPAN unexplained classification)

Programs

GEIPAN, GEPAN, SEPRA

Tags

mobile luminous mass, ground illumination, cone-shaped, UV-light description, no visible beam, no sound, A10 motorway, France, 1982, high-tension pylons, stratocumulus cloud layer

Key points

• Two on-duty gendarmes observed the phenomenon from approximately 04:35 to 04:55 on 23 January 1982 while traveling south on the A10 motorway near Trancrainville (Eure-et-Loir, department 28).p.1
• The observation was discontinuous but extended across approximately 29-32 km of road and was decomposed by GEIPAN investigators into 10 distinct phases tied to annotated map positions.p.5
• Witness 1 (T1) described a light-green ground illumination he compared to 'lumière noire' (UV/black light), with partial illumination of high-tension pylons but no visible beam between the aerial mass and the lit terrain.p.2
• Witness 2 (T2) described the aerial object as a cone-shaped gray-white form with its point directed upward and no visible light source emanating from it — a characterization that diverged in color and geometry from T1's account.p.3
• BA123 Orléans-Bricy confirmed no aircraft or helicopters were in flight at the time, and the base radar had been shut down since the previous evening.p.1
• Highway operator Cofiroute confirmed that none of its night workers, including toll-booth staff on all-night shifts, observed anything unusual along the A10 corridor.p.1
• Meteorological data showed a fully overcast sky (5-8/8 octas) with two stratocumulus cloud layers at 1200 m and 1500 m; the Moon was not above the horizon; a Saturn/Mars conjunction and Jupiter were present in the south-east.p.13
• GEIPAN's 2018 re-examination determined that no searchlight powerful enough to illuminate ground from 1500 m altitude existed in 1982; the Spectrolab SX-16 (30-40 million candela, 1.6 km range) was not deployed on French EC-145 and Puma helicopters until 2002.p.15
• The two witnesses diverged on whether the illuminated zone was stationary or moving; GEIPAN concluded T1's interpretation — a moving illuminated zone — is the only reading consistent with both witnesses' visual descriptions.p.14
• An Ingré resident reported a similar phenomenon six days prior (17 January 1982, approximately 18:30), but was never formally interviewed; GEIPAN declined to establish a link between the two events.p.4

Verbatim

• N'étant pas très sûr de mes observations, je demandais à mon passager s'il faisait les mêmes constatations que moi. Il me répondait par l'affirmative.

  p.2

• Ce n'est qu'à ce moment-là que je me suis vraiment rendu compte de la couleur de ce faisceau lumineux, qui était vert clair. Je précise qu'il ne s'agissait pas d'un faisceau mais plutôt d'une zone éclairée assez importante.

  p.2

• Il s'agissait d'une forme indéfinie ressemblant à un cône. La partie la plus pointue était dirigée vers le haut. Elle était de couleur gris clair.

  p.3

• Une ou plusieurs structures sol fixes ou mobiles n'auraient de toute façon pas pu produire ces éclairages sol mouvant sur plus de 20 km.

  p.15

• Ce projecteur n'a commencé à équiper les premier EC-145 de la sécurité civile et les hélicoptères Puma de l'Armée que 20 ans plus tard, en 2002.

  p.15

Most interesting

• T1 stopped the patrol vehicle at approximately P.K. 69.000 and exited the car to illuminate the aerial mass with a powerful flashlight; it revealed nothing further, but when he resumed driving, both the mass and the ground illumination resumed moving with the vehicle.
• Only a partial section of each high-tension pylon was illuminated rather than the full structure — GEIPAN analysts noted this is inconsistent with a wide-angle searchlight beam from 1500 m, where angular spread would illuminate a far larger area.
• T1's characterization of the illumination as comparable to 'lumière noire' (violet-spectrum UV light, approximately 375 nm) is anomalous; no conventional aviation or ground-based light source available in 1982 would produce UV-range illumination of open terrain at 600 m distance.
• Despite a press article in 'la République du centre' on 27 January 1982 publicizing the event, no additional witnesses along the entire 29 km corridor came forward.
• T2's accounts diverged between his formal procès-verbal and the newspaper article; in the PV he described a cone-shaped gray form, while the press quoted him describing 'une vague traînée gris blanc de forme effilée' — a streak rather than a cone.
• The case was originally catalogued under the name 'ORLEANS (45) 1982' despite the observation beginning in Trancrainville (department 28, Eure-et-Loir); GEIPAN's 2018 review corrected the geographic attribution.
• T2 claimed in the PV that the witnesses drove toward Ormes 'in the direction of the light,' but Ormes lies to the west while the light was consistently to the east — GEIPAN identified this as a factual error later amplified in the press account.