PIRMIL (72) 02.02.2013

In the Pirmil case dated 2 February 2013, witnesses saw several apparently stationary trails in a cloudy sky fade one after another. A child photographed them with a mobile phone. The accounts were recorded in a questionnaire and then a gendarmerie report. A sharp photograph taken at 1/125 second clearly suggests aircraft contrails. The source explains that dry north wind, at 65% humidity according to Météociel, kept them short. At sunset, 18:01 at Le Mans, the trails remained sunlit while the blue sky darkened, giving strong contrast and a flame-like appearance. Once Earth's shadow reached them, they lost illumination and became much dimmer than the sky, disappearing from view. The case is classified A: aircraft contrails.