What happened
On March 26, 2003, a DG-800S glider, registration HB-3324, crashed into a steep, snow-covered slope near Corno Mara in the Italian Alps. The flight, which began at Alzate Brianza, was intended to be a long-distance soaring mission across the Alps.
Data from an onboard flight logger revealed that the pilot had been navigating various mountain peaks throughout the day. In the final stages of the flight, the pilot was utilizing thermal currents along the southwest face of Corno Mara. During this phase, the pilot was performing 36/0-degree turns to exploit rising air. The pilot later reported encountering intense turbulence that resulted in a loss of control. The aircraft struck the terrain at approximately 2,507 meters, causing the fuselage to break and the glider to suffer irreparable damage. The pilot was severely injured and lost consciousness upon impact, eventually being rescued by helicopter the following morning.
The investigation
The investigation focused on the flight dynamics and the pilot's decision-making. Investigators examined the wreckage, which was found on a steep, vegetation-free slope, and analyzed data from a Cambridge Aero Instruments logger. This device allowed investigators to reconstruct the flight path and altitude precisely up to the moment of impact.
Technical inspections confirmed that the DG-800S was airworthy, with all maintenance and documentation up to date. The investigation also looked into the pilot's flight experience and the environmental conditions. While general weather conditions were good, the specific terrain at the crash site was prone to creating sudden downdrafts or turbulent air.
Findings
- The primary cause of the impact was the loss of control due to encountering turbulence or a strong downdraft while performing 360-degree turns near the mountain face.
- The pilot employed a risky flight technique; performing 360-degree turns near a slope is dangerous because the aircraft can end up flying toward the mountain with a tailwind and insufficient vertical separation.
- The pilot's ability to react to the sudden event was likely compromised by fatigue and a lack of recent flight training, having flown only once in the previous five months.
- Survival efforts were aided by the pilot's ability to use a mobile phone to signal rescuers, though the aircraft lacked an Emergency Locator Transmitter (ELT).
Safety action
Following the investigation, a recommendation was issued to the Aero Club d'Italia and the national civil aviation authority. The goal is to increase awareness among recreational pilots regarding survival and search and rescue (SAR) planning. Specifically, pilots should be encouraged to prepare for hostile environments by carrying appropriate gear, such as thermal clothing and signaling devices, and ensuring they have adequate means of communication for mountain operations.