What happened
On March 17, 2004, an Alexander Schleier ASK 21 glider, registration I-NIBO, was conducting a training flight after departing from Calcinate del Pesce airport. At approximately 14:52 UTC, while performing maneuvers near the ridge of Sacro Monte di Varese, the glider made contact with the treetops. The aircraft's fuselage and right wing struck branches of a fir tree, causing the glider to come to rest at an altitude of approximately 15 meters. The student pilot was uninjured, though the aircraft sustained damage.
The investigation
The ANSV investigation examined the flight path and the student pilot's actions during the maneuver. The investigation established that the student pilot had approximately 20 hours of total flight time, all on this specific aircraft type. Meteorological conditions at the time of the accident were favorable, with excellent visibility and no wind or precipitation.
Evidence from the pilot'1s account indicated that after releasing from the tow plane, the pilot flew toward the ridge of the mountain. While performing turns parallel to the ridge, the pilot approached the forested area within a distance of roughly 50 meters. The pilot admitted to a superficial assessment of the distance between the glider and the mountain, which resulted in a loss of approximately 30 meters in altitude. In an attempt to regain airspeed after the speed dropped below 90/95 km/h, the pilot initiated a slight dive, which ultimately led to the impact with the trees.
Findings
- The primary cause of the accident was the inadequate assessment of altitude and distance from the treetops by the student pilot during a maneuver performed too close to the wooded ridge.
- The limited flight experience of the student pilot contributed to the occurrence.