Accident to the hot air balloon Kubicek BB14XR registered OK-8281 on 28/04/2023 at La Chapelle-en-Lafaye

This is a courtesy translation by the BEA of the Final Report on the Safety Investigation. As accurate as the translation may be, the original text in French is the work of reference.

Note: The following information is principally based on the pilot’s statement. This information has not been independently validated by the BEA.

1.History of the flight

The pilot took off from a field near the town of Arlanc for a flight eastwards to the village of Viverols  in the Ance valley. During the flight, at an altitude of 3,500 ft, she noted a westerly wind of around 20 to 25 km/h, gusting to 30 km/h. Arriving in the Ance valley near the village of Églisolles, she started her descent. Due to the wind at the bottom of the valley, she was unable to find an area suitable for landing.

Still heading east, as she approached a forest, she climbed to cross the ridge line and then attempted a new approach over a large field near the village of La Chaulme. A change in wind direction (from the south) brought her close to a line of trees and forced her to climb again.

After flying over a village, and still looking for an area to land in the direction of La Chapelle-en-Lafaye, the balloon was hit by a gust of wind that pushed it eastwards on a downward path towards a power line. The pilot realised that she would not have time to climb back up before reaching the power line and decided to make an emergency landing. She activated the valve and shut down the gas supply to the burners. She managed to land in front of the power line on sloping ground, but another gust of wind pushed the envelope of the balloon onto the line.

Figure 1: key points of the flight (source: IGN map, annotated by the BEA)

2. Additional information

The basket was resting on the ground and had not been damaged in any way. The envelope of the balloon, which was in contact with the power line, had been burnt by the electric arcs when the line short-circuited.

When preparing for the flight, the pilot had consulted the WINTEM chart for 08:00 (06:00 UTC) and obtained the meteorological data for the surrounding aerodromes as well as the wind cross-section for the planned landing site via the meteociel website.

The 05:00 METAR for Clermont-Ferrand airport, located 60 km north-west of the take-off site, indicated a variable wind at 3 kt and CAVOK. The METAR for Saint-Étienne-Bouthéon airport, 50 km east of the take-off site, indicated a wind from 180° at 6 kt and CAVOK.

The wind cross-section indicated a south-westerly wind of less than 5 km/h at surface level, a westerly to south-westerly wind of 11 km/h at 1,200 m, a westerly to south-westerly wind of
16 km/h at 1,500 m, and a westerly to north-westerly wind of 23 km/h at 2,000 m. The WINTEM chart forecast a wind of 5 kt at level 20 and 10 kt at level 50 in the area of the flight.

The pilot, who held a hot-air balloon pilot licence obtained on 9 March 2023, had logged 62 flights, including 29 flights as pilot-in-command, and 57 flight hours.

The pilot stated that she had thought that the weather conditions were favourable for the flight. She had noted that, in the Rhône valley, a strengthening southerly wind was expected over the Lyon region from 08:00, but that this strengthening was not indicated by the stations closer to the area where she had planned to fly.

She added that during the flight, given the strength of the wind in the upper levels and the rate of descent, she was not able to descend quickly enough into the Ance valley to be protected from the wind. She added that when she attempted to land in the following valley, the wind seemed calmer, but this was probably due to the masking effect of the trees. When the balloon left this protected area, the turbulent wind pushed it towards the power line.