Sighting in Carrières-sous-Poissy, October 1, 2011

At about 5 p.m., four people sitting in a house garden saw an oval object, shaped like a capsule, fall quickly from the sky. It stayed horizontal, swayed and spun on itself. It was grey and looked metallic. Afraid of being hit, the witnesses left the garden and drove away.

They warned some passers-by, who saw nothing because trees blocked the sky. The witnesses stopped near a stadium a few hundred metres away and looked back, but could no longer see the object. Another person, whom the main witness met, said they had seen it head off toward Triel-sur-Seine, to the north-northwest. The witnesses, deeply puzzled, then went home.

Because the object moved with the wind, GEIPAN favoured the explanation of a balloon lighter than air. Tube-shaped balloons are known to a few enthusiasts, and a spinning movement carried by the wind fits that explanation. The grey plastic film used for these balloons looks metallic once inflated and lit by the sun. The witnesses, who had never seen such an object, could not estimate its size or distance precisely. Its modest size, around 3 m, would also explain why so few people noticed it. GEIPAN classified the case B: probably a tubular hot-air balloon.