What happened
On the morning of September 18, 2004, a Chaize Balloon CS 3000 F 16 hot air balloon, registered F-GGRT, was conducting a recreational flight near Maintenon. The pilot, accompanied by two passengers, departed from the Maingournois base at approximately 08:00. After roughly 75 minutes of flight, the pilot noted that the wind speed was increasing.
To avoid high-voltage power lines located behind a nearby wooded area, the pilot attempted to land approximately 100 meters before the trees in a cultivated field. During the descent from an altitude of about 200 meters, the pilot initiated a rapid descent. As the basket approached the ground, the pilot attempted to manage the vent valve using a rope wrapped around his arm. However, the impact with the ground was violent, causing the basket to bounce. This motion caused the vent rope to release prematurely, preventing the pilot from effectively venting the hot air. Consequently, the partially deflated envelope caught the wind, creating a parachute effect that dragged the basket across the ground for about 100 meters until the envelope became entangled in the trees.
The investigation
The investigation examined the pilot's decision-making process and the flight's final moments. It was noted that the flight was part of a club event where weather forecasts had been communicated verbally to participants. While other balloons had landed successfully earlier that morning, the pilot identified that the increasing wind strength influenced his choice of landing site. The investigation also looked into the mechanical state of the aircraft and the pilot's physical actions during the landing sequence.