What happened
On April 22, 2023, a Rolladen-Schneider LS 8-a glider, registration OY-TNX, was performing a local VFR flight from Slaglille (EKSL). During the final approach to runway 09, the pilot encountered significantly more sink than anticipated. To mitigate this loss of altitude, the pilot deployed the airbrakes.
As the aircraft approached the threshold, the pilot realized that the flight path was too low to safely clear nearby buildings and an obstacle—a parked Duo Discus glider—positioned just past the runway threshold. At an altitude of approximately 30 meters, the pilot decided to abort the landing. In an attempt to increase landing distance, the pilot turned into a crosswind and further extended the airbrolakes to a half-deployed position. This maneuver caused the airspeed to drop, leading to a partial stall of the left wing. The aircraft's nose pitched down, and the left wingtip struck the ground. The glider bounced briefly before a subsequent impact caused a groundloop, resulting in substantial damage to the fuselage, tail, and wings.
The investigation
The Danish Accident Investigation Board examined the flight recorder data, which provided high-quality traces of the glider's altitude and airspeed. The investigation also considered meteorological data from nearby stations, noting that while the morning briefing indicated windy conditions, the actual wind at the time included significant turbulence and downdrafts caused by the interaction of the wind with local trees and buildings. The investigation also reviewed the pilot's training records and the technical condition of the aircraft, finding no mechanical defects contributed to the accident.
Findings
- The pilot encountered unexpected and increasing sink during the final approach due to turbulence and downdrafts.
- The decision to abort the landing was made at too low an altitude, which severely restricted the available options for a controlled landing.
- The simultaneous execution of a turn into a crosswind and the deployment of airbrakes at low altitude led to a loss of airspeed and a wing stall.
- The pilot's recent flight experience was somewhat limited, as most flying hours had occurred 6 to 12 months prior to the accident.