What happened
On January 10, 2022, a Cameron N-145 hot air balloon, registration OY-SOCT, was conducting a recreational flight that began in Dobbiaco. After approximately sixty minutes of flight, the pilot attempted to land in the Cortina area. During this initial descent, the balloon encountered unexpected wind conditions, with surface winds ranging between 5 and 15 knots. The aircraft struck trees, causing damage to two panels of the envelope.
Following this incident, the pilot continued the flight for about another hour in search of a suitable landing site. While flying over Forno di Zoldo, the balloon encountered a strong, localized downdraft. Despite the pilot applying full heat using both burners, the aircraft could not maintain altitude and descended into a residential area. The balloon struck a street lighting pole, bending it, and subsequently hit a residential building and power lines before the basket came to rest between two buildings, causing minor damage to a garage. The incident resulted in one passenger with serious injuries.
The investigation
The ANSV investigation confirmed that the pilot's license and medical certificate were valid, and all maintenance records for the OY-SOCT were up to date. The investigation focused on the meteorological conditions and the sequence of events following the initial damage to the envelope. Investigators examined the impact of orographic turbulence and downdrafts common in mountainous terrain, noting that while the weather was generally suitable for flight, localized phenomena played a critical role.
Findings
- The primary cause of the accident was inadequate flight planning regarding the specific meteorological challenges of a mountainous environment.
- A lack of precise planning for landing sites in relation to mountain-induced wind patterns led to the first landing attempt in Cortina, which caused damage to the balloon's envelope.
- The pre-existing damage to the envelope panels likely compromised the aircraft's performance, preventing the pilot from achieving the rapid ascent necessary to avoid ground structures during the second encounter with a downdraft.
- Localized downdrafts and orographic turbulence contributed to the uncontrolled descent during the final landing attempt.