What happened
On August 17, 2013, a Cessna FR 172J, registration D-EDQL, crashed into the southwest slope of the Marmolada massif near Passo Ombretta, in the municipality of Pozza di Fassa. The aircraft had departed from Bolzano airport for a local sightseeing flight.
During the final stages of the flight, the aircraft was observed by witnesses flying at a very low altitude near the mountains. Witnesses reported seeing the aircraft undergo longitudinal oscillations, followed by a loud boom and the sight of flames and smoke rising from the terrain. The impact occurred at an altitude of approximately 2,672 meters. The aircraft was destroyed upon impact and a violent fire broke out immediately afterward. All four people on board lost their lives.
The investigation
The ANSV investigation examined the aircraft's maintenance history, the pilot's experience, and the environmental conditions at the time of the accident. The investigation confirmed that the aircraft had undergone all required maintenance and that the engine and propeller were in good working order. Fuel samples taken from the Aero Club Bolzano storage tank were analyzed and found to be uncontaminated avgas.
Investigators also analyzed the aircraft's weight and performance. At takeoff, the aircraft was carrying a significant load, with a total weight estimated to be very close to its maximum takeoff mass (MTOM). Meteorological data showed that temperatures were approximately 13°C above standard, which negatively impacts engine performance and climb rates. Radar data was inconclusive due to the low-altitude flight and mountainous terrain, but radio communications confirmed the pilot was flying under Visual Flight Rules (VFR).
Findings
- The primary cause of the accident was the loss of control due to an aerodynamic stall during a critical phase of flight.
- The pilot's limited flight experience (less than 100 total hours) and potentially inadequate knowledge of the aircraft's performance limitations contributed to the event.
- The aircraft was operating with reduced safety margins regarding altitude and airspeed.
- The high density altitude, caused by temperatures significantly above standard, reduced the available engine power and climb performance.
- Mountainous downdrafts or orographic weather phenomena may have contributed to the sudden loss of altitude.
- The high weight of the aircraft, being near its maximum allowable limit, further reduced the margin for error during maneuvers or climbs.