What happened
On September 8, 1975, a Dornier Do 27 A-I, registration D-EIVI, departed from Lugano-Agno for a visual flight rules (VFR) trip to Egelsbach, Germany. The flight, which included the pilot and four passengers, was intended to traverse the Alps. Prior to departure, the pilot consulted with the Zurich flight weather center and received a warning regarding critical conditions over the mountains. Despite being advised by a professional pilot on the ground to take a longer route via the Simplon Pass to avoid hazardous weather, the pilot chose to proceed via the San Bernardino route, likely due to time constraints.
As the aircraft progressed through the mountains, it encountered heavy cloud cover and fog. Witnesses near the Passetti Pass observed the aircraft flying within low cloud layers and performing a circling maneuver. During an attempt to execute a turning maneuver to avoid terrain, the aircraft entered an uncontrolled flight state and struck the southern flank of Pizzo Rotodend at high speed and a near-vertical angle. The impact resulted in 5 fatalities and the total destruction of the aircraft.
The investigation
Investigators examined the wreckage and the flight path, noting that the aircraft's engine was still producing power at the moment of impact. The investigation confirmed that the aircraft was within its center of gravity limits, though it may have been near its maximum takeoff weight. While the pilot was a licensed private pilot, the investigation highlighted a lack of specific experience regarding mountain flying. Furthermore, the investigation looked into the weather conditions, finding that while some layers of clouds had temporarily thinned, the San Bernardino and Passetti Pass areas were obscured by fog, and the Calancatal valley was covered in low-lying clouds.
Findings
- The pilot continued a VFR flight into terrain and weather conditions that were highly unfavorable.
- The aircraft entered an uncontrolled flight state during a turning maneuver.
- There was a significant misjudgment of the actual weather conditions both on the ground and in the air.
- The pilot demonstrated limited general flying experience and a specific lack of experience in mountain operations.