Sighting in « le Trou Normand » Brix, October 27, 1989

At about 9 a.m., the owner of a field found a large, completely scorched area in their meadow. The irregular mark was around 17 metres long and 4 metres wide at its widest point. No vegetation remained; the soil was black and spongy, and had sunk 10 to 15 cm below the general level of the meadow. A 20 kV high-voltage line ran alongside the plot, about fifty metres from the mark. The local police brigade could not determine the origin of the phenomenon and called in the SEPRA, which went to the site quickly.

Another witness told the gendarmerie that during the night of 25 to 26 October, at around 2 a.m., their dog had behaved strangely and a broad, intense, bluish beam of light had lit up the field. This witness had also seen a very large blue flame over the area.

Core samples showed the soil was burned to a depth of 2 to 3 cm, and the grey colour of the clays indicated exposure to high temperature. The samples smelled strongly of petroleum products, and analyses confirmed the presence of kerosene. The hypothesis put forward is that an aircraft flying low and slowly released kerosene. The cloud could have ignited as it passed through the high-voltage line, whose insulators were crackling loudly during the investigation, with sparks possibly setting it alight. The blue flame, a colour typical of hydrocarbon combustion, supports this explanation. The case was classified B: the ground traces were left by a fire.