What happened
On April 23, 2004, an Ultramagic M 77 hot air balloon, registration EC-FVL, was conducting a promotional flight over the city of Santiago de Compostela. The flight, operated by Globoacción Aérea Comercial, S. L., was being flown at an extremely low altitude, estimated to be no higher than 20 meters, likely to maximize public visibility and avoid higher-altitude winds.
As the balloon passed over the Campus Sur of the University of Santiago, the basket collided with the metal cap of a chimney that slightly exceeded the height of surrounding structures. The impact tore the iron cap from the chimney and a sharp corner of the metal piece punctured a propane cylinder. This caused a massive, high-pressure release of gas that immediately ignited due to the active burners.
The resulting fire was exceptionally violent and rapid, consuming the organic components of the basket almost instantly. In a desperate attempt to escape the flames, the pilot and two passengers jumped from the basket. All 3 fatalities occurred as a result of the fall. Following the impact, the loss of weight and the intense heat caused the unmanned, burning envelope to ascend and drift approximately 8 km before the wreckage was found in a wooded area.
The investigation
The CIAIAC investigation examined the aircraft's maintenance records, the pilot's experience, and the meteorological conditions at the time of the accident. The investigation established that the aircraft had a valid airworthiness certificate and had undergone all required annual maintenance. The pilot was highly experienced, with over 500 flight hours.
Investigators analyzed the flight path and the sequence of the impact. Because there were no survivors and no flight recorders, the investigation relied on witness testimony and physical evidence from the wreckage. The inquiry focused on why the balloon was flying at such a low altitude and why the pilot's evasive maneuver failed to prevent the collision.
Findings
- The primary cause of the accident was the maintenance of a low flight altitude, which allowed the basket to strike the chimney.
- The pilot had initiated an upward evasive maneuver prior to the impact, but the maneuver was too late to avoid the obstacle.
- The delay in the pilot's reaction may have been caused by a distraction, an incorrect estimation of the aircraft's response time, or obstructed visibility caused by passengers or objects within the basket.
- The flight was being conducted without prior authorization to enter the Santiago de Compostela (LESTA) controlled airspace.
- The impact with the chimney's metal cap directly caused the puncture of the propane tank, leading to the catastrophic fire.