What happened
On April 15, 2004, a Rolladen-Schneider LS6 glider, registration HB-1924, was engaged in a training flight launched from Bad Ragaz airport. After being towed and releasing from the tow plane at approximately 1,552 meters, the pilot began soaring in the vicinity of the airport.
By late afternoon, the aircraft was flying near Domat-Ems. Flight data recorders indicate that the pilot navigated south of the Kunkel Pass toward Trin. During the flight, the aircraft performed a left turn to move away from the terrain, followed by a right turn onto a heading of 040 degrees toward the Taminatal valley. At 17:14, the LS6 struck a snowy mountainside at a speed of 91 km/h. The impact caused the aircraft to break into two pieces and slide 250 meters down a steep slope. The pilot sustained fatal injuries.
The investigation
Investigators from the Swiss Transportation Safety Investigation Board (SUST) examined the wreckage and analyzed flight data from two onboard loggers. The investigation also included a review of meteorological conditions, which at the time of the accident included cloud cover, localized snow showers, and diffuse lighting.
Medical examinations and an autopsy were conducted to determine the pilot's physiological state. The autopsy revealed cardiac changes consistent with hypertension. Furthermore, toxicological analysis identified the presence of amphetamines, benzodiazepines, and beta-blockers in the pilot's system.
Findings
- The primary cause of the collision with the terrain was likely the loss of necessary visual references, potentially due to the combination of snow showers, cloud bases, and diffuse lighting.
- The pilot was operating under the influence of amphetamines and benzodiazepines, substances that are incompatible with the safe operation of an aircraft due to their effects on judgment and reaction time.
- Post-mortem findings of cardiac abnormalities related to high blood pressure, alongside the effects of the identified medications, cannot be ruled out as contributing factors to the accident.