SAULCE (LA) (05) 20.01.2012

Around 08:25 on 20 January 2012, a woman and her daughter at La Saulce (05) saw an intriguing phenomenon in the clear sky above Col de Blaux. She photographed a thin white smoke-like trail whose left end became black before disappearing behind the mountain towards the Le Caire valley (04). She thought something might have fallen and crashed, but saw no aircraft and heard no unusual noise. She gave a statement to the gendarmerie. Investigators found no ground trace, no further accounts among valley residents and no sign of vegetation burning or fire in the area. A military-aircraft passage could not be confirmed. The gendarmes noted that sunrise at that season and time was low and dazzling, which might explain the trail's colour change. Several press and internet articles covered the sighting. The investigation considered an aircraft crash, smoke originating on the ground and an aircraft contrail; see the report. GEIPAN classified the case B: very probable observation of a persistent contrail distorted by wind shear since its formation. It explains that the grey section had not yet been illuminated by the rising Sun.