What happened
On the evening of 22 April 2011, a Kubicek SPOL. S.R.O. – BB37N hot air balloon was conducting a flight near Oostkamp, Belgium. The flight, which carried six people including the pilot, a flight attendant, and four passengers, began uneventfully under stable conditions. However, around 18:00 UTC, the weather deteriorated rapidly as wind speeds increased significantly, jumping from approximately 12 km/h to over 50 km/h within minutes.
Faced with worsening conditions, the pilot attempted an emergency landing in a field near the Brugge-Oostende waterway. During the touchdown, the basket experienced a violent 180-degree rotation. The force of the impact caused the pilot to strike his head against the burner structure, rendering him unconscious. As the basket continued to slide across the ground, several occupants were ejected. One passenger sustained serious injuries after being thrown from the basket, and a flight attendant was also ejected. The balloon continued to travel for several hundred meters before coming to a final rest in a ditch. Despite rescue efforts by ground crew and bystanders, the pilot was found dead in the water.
The investigation
The AAIU(Be) examined the aircraft, the meteorological data, and the sequence of events leading to the impact. The investigation confirmed that the OO-BHA was airworthy and the pilot was highly experienced, with over 4,600 flights. Investigators analyzed the wind conditions, noting that while a forecast had indicated a risk of thunderstorms, the sudden shift in wind direction and speed was the primary driver of the accident.
Technical analysis of the basket and restraint system revealed that the pilot's equipment provided limited protection against vertical movement, which likely contributed to his head striking the burner frame. Furthermore, the investigation looked into the passenger briefing process, noting that while no formal pre-flight briefing was recorded, instructions were given in-flight just before the landing.
Findings
- The primary cause of the accident was a fast landing performed under unfavorable weather conditions.
- The sudden change in wind speed and direction necessitated an emergency landing that the pilot could not manage without injury.
- The pilot became incapacitated due to the violent impact of the basket rotating upon touchdown.
- The positioning of passengers, who were instructed to hold onto burner support rods, contributed to the instability of the occupants during the rotation.
- The rapid deflation system was not activated because the pilot was unconscious following the initial impact.