What happened
On May 12, 2008, a BB30Z hot air balloon, registration OK-5000, was conducting a flight that began near Hrdlív. During the flight, the pilot noted a change in wind direction that threatened to drift the aircraft into the Prague Ruzyně CTR airspace. To avoid this controlled airspace, the pilot decided to land in a field near the village of Svinařov.
As the pilot approached the landing site, two 22 kV power lines were identified on the edge of the field. While passing over the first set of lines, the balloon experienced a sudden loss of altitude due to intense heating efforts by the pilot. The pilot was unable to correct this descent in time, causing the edge of the basket to strike the second set of power lines. The impact caused the balloon envelope to tilt sharply, leading to a partial loss of hot air and a burn hole in the fabric. The subsequent loss of lift caused the basket to strike the ground with significant force. One passenger sustained a serious injury, specifically a fractured lumbar vertebra.
The investigation
The ÚZPLN investigation examined the flight sequence, the meteorological conditions, and the pilot's decision-making process. The investigation established that the pilot was properly qualified and the aircraft was in a valid state of airworthiness. The investigation also noted that the 22 kV line branch was not marked on the regional tourist map used by the pilot for orientation. Furthermore, the investigation looked into the impact of the terrain on the descent rate and the physical damage to the balloon envelope and the electrical infrastructure.