What happened
On June 20, 2003, a Schleicher ASK-21 glider, registration PH-687, was performing a local flight from the Terlet gliding airfield with one passenger on board. During the flight, the pilot utilized thermal activity to gain altitude before beginning the return to the airfield. Due to wind conditions of approximately 15 knots, the pilot executed a higher-than-normal traffic pattern, flying the upwind leg at 300 meters, the crosswind leg at 200 meters, and the final approach at 150 meters.
As the aircraft reached the final approach, the pilot attempted to deploy flaps to manage the landing. However, the pilot immediately closed the flaps because the aircraft experienced a significant increase in sink rate. Realizing the airfield was no longer reachable due to the high rate of descent, the pilot maneuvered the aircraft to the right to avoid hitting an elevated path located across the flight path. This maneuver caused the glider to lose most of its forward airspeed, resulting in a nose-down impact with the ground. The impact caused heavy damage to the nose and both cockpit canopies, though there were no injuries to the occupants.
The investigation
The investigation focused on the pilot's management of the approach in the presence of specific wind conditions. The inquiry examined the flight path, the decision-making regarding flap deployment, and the aerodynamic consequences of the pilot's corrective maneuvers during the final stages of the flight.