What happened
On July 26, 2018, a Schempp Hirth Janus B glider, registration PH-1463, was conducting a local instructional flight near the Chambéry Challes-les-Eaux aerodrome. The flight, operated by Gilzer Luchtvaart Club, involved a student pilot and an instructor performing a winch launch. After releasing the cable at approximately 350 meters, the student pilot began flying along the ridge to the east of the airfield, maintaining a south-southeast heading.
During the flight, the student pilot executed a right-hand turn to follow the slope in a north-northwest direction. During this maneuver, the aircraft drifted too close to the rising terrain. Although the instructor attempted to take control of the aircraft, the right wing struck the treetops. The glider subsequently collided with dense vegetation and impacted the ground in a forested area roughly 1.5 kilometers east of the aerodrome. The accident resulted in one injury (the student pilot) and the destruction of the aircraft.
The investigation
The investigation examined the wreckage at the crash site, which was located on a mountainside within a dense forest characterized by trees exceeding 20 meters in height. The wreckage was found in a nearly vertical position, with the forward section of the glider destroyed by the ground impact. Investigators noted significant impact marks on the wing leading edges and broken branches, which likely helped absorb some of the impact energy.
Weather conditions at the time were reported as CAVOK with variable winds of approximately 5 knots. The investigation also reviewed the flight experience of the crew, noting that the instructor was a qualified instructor with approximately 500 flight hours, while the student pilot was in the early stages of training, having completed nine hours of instruction with this specific instructor since July 23, 2018.
Findings
- The primary cause of the accident was the student pilot's misperception of the distance between the aircraft and the terrain/vegetation during a ridge soaring turn.
- A contributing factor was the instructor's lack of vigilance, which resulted in the instructor taking control of the aircraft too late to prevent the wing strike.