What happened
On July 4, 2006, a Beechcraft 1900D, registration F-GTVC, operated by Twin Jet, was performing a scheduled passenger flight from Lyon Saint-Exupéry to Angoulême Brie Champniers. The flight carried 15 passengers and 2 crew members.
As the aircraft was on final approach to Angoulême, a highly active thunderstorm cell moved into the airfield area. The wind shifted rapidly from the northwest to the southwest, accompanied by increasing gusts and a lightning strike reported on the ground. Due to the crosswind component exceeding the aircraft's landing limitations, the commander initiated a missed approach at approximately 810 feet.
To avoid the storm cell located south of the airfield, the crew executed a right turn to climb toward 5,000 feet, seeking clear air. While maneuvering northeast of the airport, the aircraft entered a zone of severe turbulence for approximately two and a half minutes. During this period, the aircraft's airspeed fluctuated between 160 knots and 250 knots (VMO), and the vertical load factor varied between -0.3g and +1.9g. The aircraft's attitude shifted significantly, with pitch changes of up to 13 degrees and bank angles reaching 42 degrees.
Following the turbulence, the crew decided to divert to Limoges Bellegarde, where weather conditions were more favorable. The aircraft landed safely at Limoges at 20:20 UTC.
The investigation
The investigation was based on several data sources, including Bordeaux radar tracks, the aircraft's Flight Data Recorder (FDR), radio communications with the Angoulême AFIS agent, the flight crew's reports, and testimonies from three passengers.