What happened
During an introductory flight, an instructor and a student were performing a standard approach when the aircraft experienced a sudden left bank at an altitude of approximately 70 meters. The instructor, attempting to stabilize the aircraft using right rudder and aileron inputs, found that the aircraft continued to turn left uncontrollably.
In an effort to avoid a wooded area in the flight path, the instructor increased the rate of the turn. The aircraft completed a 270-degree turn before impacting the ground nose-first. Following the impact, the aircraft yawed an additional 90 degrees and slid into a wooded area. The instructor exited the aircraft unassisted, while the student sustained a broken left foot.
The investigation
SHK investigators examined the aircraft's rudder mechanism and discovered that the right bolt used for the rudder cable attachment had made contact with a fuselage fairing.
To understand the flight dynamics, SHK performed a reference flight using an identical aircraft type. During this test, the aircraft was flown at a standard final approach speed of 110 km/h with landing flaps extended. The investigators simulated the accident conditions by banking the aircraft 15 degrees to the left and holding the rudder in the position where it was potentially obstructed. When right aileron input was applied to correct the flight path, the aircraft's heading shifted 45 degrees to the left, demonstrating the difficulty of maintaining control under such conditions.
Findings
While a definitive cause could not be established, the investigation concluded that the rudder deflection to the right was likely obstructed because the rudder cable bolt caught on the edge of the cable fairing and became stuck. This mechanical interference prevented the pilot from using the rudder to counteract the left bank.
Safety action
As a result of the findings, a safety recommendation was issued to EASA. The recommendation suggests updating daily inspection checklists and post-hard-landing inspection protocols to ensure that any excessive play or insufficient clearance between the rudder cable bolts and the fairings can be identified during routine maintenance.