A loud explosion noise startled the inhabitants of part of the Dordogne this Friday, April 26, at 10:33 a.m. precisely. “I heard a big boom”, says Thomas, who lives in Saint-André-d’Allas. The sound also resounded in Sarlat, Cadouin, Saint-Cyprien, Hautefort or Montignac, and even as far as Brive and Cahors, in the neighboring departments of Corrèze and Lot. It was in fact a fighter plane having broken the sound barrier.
The bang scared Thomas very much: “The windows vibrated. I really wondered what it was, what could have made so much noise, so much movement. I have gas canisters here, so I thought that was what had exploded at first I wondered if it was something nearby that had fallen. I went around, nothing at all!”
Pilots training to break the sound barrier
The National Air Operations Center (CNOA) explains that the noise was caused by an Air Force Rafale. The aircraft took off from Mont-de-Marsan, in the Landes, this Friday morning to training in an air corridor which passes over the Dordogne. This “usual, authorized exercise” aimed precisely to allow pilots to “practice passing the speed of sound”.
A plane passes the sound barrier when it exceeds 1,200 km/h. At this speed, the sound pressure waves generated by the aircraft, such as engine noise, can no longer travel away from the aircraft. They accumulate at the front, which forms a shock wave, a sort of “bubble of air”, as explained by the former host of “It’s not rocket science”, Jamy Gourmaud on his Twitter account. It causes a supersonic boom, a powerful and short noise just after the plane passes.
