What happened
On May 29, 2005, a Rolladen Schneider LS-6 glider, registration D-2569, was engaged in a recreational flight when it struck the side of Monte S. Gregorio in the Traversella region of Italy. The pilot, an experienced glider pilot with over 1,450 total flight hours, had departed from Torino Aeritalia earlier that day.
During the final stages of the flight, while performing a climbing maneuver (spiraling) to find thermal lift, the aircraft approached the mountain ridge. The impact occurred at an altitude of approximately 1,450 meters. The force of the collision destroyed the cockpit and forward fuselage, and the pilot sustained fatal injuries.
The investigation
The ANSV investigation focused on the flight data recorded by a cockpit logger, which provided critical information regarding the aircraft's trajectory and performance prior to the crash. The wreckage analysis showed that the debris was concentrated in a very small area, suggesting a low-energy impact with a high angle of descent.
Investigators examined the aircraft's condition and found it to be airworthy, with all maintenance and inspections up to date. The meteorological conditions at the time involved clear skies with some cloud cover and moderate thermal activity. Data from the logger revealed that the glider was in a right-hand spiral at the time of the accident, but was struggling to maintain altitude, resulting in a progressive approach toward the terrain.
Findings
- The primary cause of the accident was a right-wing asymmetric stall, which caused the glider to enter a sudden, steep dive.
- The pilot was unable to execute a recovery maneuver due to the proximity of the terrain and the suddenness of the stall.
- Contributing factors included the presence of irregular thermal currents that may have increased the angle of attack on the right wing.
- The pilot may have intentionally tightened the turn to avoid the approaching mountainside, inadvertently reducing the safety margin and triggering the stall.
- A potential reduction in situational awareness or a momentary lapse in attention may have also contributed to the event.