BAGNERES-DE-BIGORRE (65) 22.05.2017

On 22 May 2017 at about 21:45, a witness at his window in Bagnères-de-Bigorre (65) saw an orange trail in the sky toward Tarbes. He first thought it was an aircraft trail, but its thickness, and especially its curved path, puzzled him and made him think an aircraft was in difficulty. He took a series of photographs and subsequently contacted 2 gendarmerie stations. No other account was collected. Analysis of the photograph and the features the witness found unusual, namely the trail's width and the time it took to dissipate, led GEIPAN to consider an aircraft dumping fuel; see the investigation report. The same analyses allowed possible aircraft positions and speeds to be reconstructed. GEIPAN rejected an airliner explanation because the aircraft should have appeared on public flight-tracking websites and, above all, because such fuel dumping would have accompanied a diversion and should have left a record. By contrast, GEIPAN considered it normal for a military aircraft to be absent from public tracking records. Its absence from the CNOA radar data was also explainable: the requested search radius had been too small, and the data could no longer be obtained after 2 months. The CNOA could not supply an operational fuel-dumping record. However, the search began too late to investigate all French squadrons, after the time needed for the investigation to develop this hypothesis. Moreover, such an operation would not necessarily have been recorded, since it is not always a critical operation for a military aircraft. In this context, GEIPAN considered that the absence of a military aircraft record or fuel-dumping record did not invalidate the hypothesis. It retained that explanation because of the close match between the visual appearance, both reported and photographed, and the possible flight paths reconstructed from the photograph. The evidential strength is good, with a precise account and photographs suitable for analysis. GEIPAN therefore classifies the case as B: probable observation of a military aircraft dumping kerosene at high altitude, presumably to limit environmental impacts and impacts on the population, as the French summary puts it; the narrative describes these as environmental impacts on the population.