What happened
On 23 August 2005, a Cessna 1 72P, registration OK-HOS, departed Locarno aerodrome for Friedrichshafen. The flight proceeded through the Gondoschlucht toward the Simplon Pass. During the flight, the aircraft began a continuous descent while traversing the valley. As the aircraft approached the Bärnetscha area, approximately 6 km from the pass summit, the crew attempted a 180-degree turn. This maneuver was initiated too late, causing the aircraft to tip over and strike the terrain. The impact resulted in four fatalities and the total destruction of the aircraft.
The investigation
Investigators examined the aircraft's flight history, weight and balance, and the meteorological conditions at the time of the accident. GPS data was recovered from a unit found outside the wreckage, allowing for a reconstruction of the flight path. The investigation also reviewed the pilots' flying experience and the technical state of the aircraft. No pre-existing mechanical defects were found to have contributed to the crash. The investigation also analyzed the impact dynamics, noting that the aircraft struck the ground with a near-vertical inclination.
Findings
Several critical factors contributed to the loss of control:
- The aircraft was overloaded, with a takeoff mass of 2600 lb, exceeding the maximum permissible limit of 2400 lb.
- The centre of gravity was outside the aft limit, specifically at 48.28 inches, which adversely affected the aircraft's stalling characteristics.
- The pilots had limited flying experience, with the left-hand pilot having only approximately 20 hours of experience since passing his examination.
- Challenging meteorological conditions, including strong downdraughts caused by a north foehn wind, made the flight difficult to manage.
- The 180-degree turn was initiated too late to safely clear the terrain.