What happened
On July 7, 2010, a Schempp-Hirth Duo Discus glider departed from the Görlitz airfield (EDBX) via winch launch for a thermal soaring flight. The aircraft was accompanied by a passenger. Approximately 20 minutes into the flight, while performing a turn, the pilot experienced a failure of the rudder control system. The rudder pedals shifted into the forward position and, although the pilot was able to release the locking mechanism and pull the pedals back, they could no longer be secured in the rear position. Consequently, the pedals remained in the forward position, which was unreachable for the pilot's feet.
Following the malfunction, the pilot maintained a straight flight path and identified an unprepared landing field located north of the airfield. The pilot notified the airfield controller of the emergency and the intention to perform an outlanding. At 14:48 local time, the glider landed in a grain field approximately 1.5 meters high. The impact resulted in heavy damage to the aircraft, including partial tearing of the wing skin and deformation of the outer wing attachments, but there were no injuries to the occupants.
The investigation
The BFU examined the aircraft and the mechanical state of the rudder controls. An aeronautical engineering firm conducted a specialized inspection of the rudder pedal adjustment mechanism in the forward cockpit. This investigation focused on whether the locking mechanism was prone to spontaneous movement or failure.
Findings
- The investigation established that the rudder pedal adjustment mechanism was capable of being securely locked in all positions.
- The pilot's flight experience was limited, with only 15 total flight hours and approximately 3 hours on this specific model.
- The primary cause of the landing was the unintended forward movement of the rudder pedals and the subsequent inability to lock them in the rear position.