What happened
On April 28, 2012, an aviation event was taking place at the Arnstadt-Alkersleben airfield. During the event, a formation of four aircraft—consisting of two Moravan Z 226 Trener and two Z 526 AFS models—performed a series of maneuvers. After several passes, including a diamond formation, the aircraft transitioned into a line formation with approximately 100-meter spacing between following aircraft, though the gap between the leader and the second aircraft exceeded 200 meters.
The formation was flying at a height of between 150 and 200 meters with a speed of 220 km/h. The plan was for all four aircraft to execute a left roll simultaneously over the runway. However, the second aircraft in the formation failed to initiate the maneuver at the same time as the others, only beginning its roll after the third and fourth aircraft were already inverted. During this delayed roll, the aircraft deviated significantly from its original course, reaching a steep bank and eventually entering a vertical dive. The aircraft struck the ground in the lower quarter of a recovery arc, resulting in the fatal injury of the pilot and the destruction of the Moravan Z 226 Trener.
The investigation
The BFU investigation focused on the pilot's training, the formation's maneuvers, and the oversight provided by the event organizers and authorities. Investigators examined the pilot's flight logs, which revealed very limited aerobatic experience, totaling only about 15 hours of documented aerobatic flight since 2003. The investigation also scrutinized the certification process, noting that the pilot's aerobatic checkride had been conducted by an instructor who had been heavily involved in his initial training.
Furthermore, the BFU examined the regulatory environment of the airshow. The investigation found that the event permit allowed for aerobatic maneuvers at heights as low as 100 meters, without differentiating between solo and formation aerobatics. The BFU also noted that the required demonstration flight (Vorfliegen) to the event organizer, which would have allowed for an assessment of the pilots' proficiency, was not conducted.
Findings
- The primary cause of the accident was an incorrectly initiated roll combined with the pilot's insufficient aerobatic experience to recover the aircraft under the specific flight conditions.
- The pilot lacked the necessary routine and training to safely perform maneuvers at altitudes below the standard 450-meter limit.
- The team leader failed to recognize the pilot's inadequate training level.
- The event organizer lacked specific criteria to verify the proficiency of participating pilots.
- The regulatory oversight by the local aviation authority was insufficient, as it did not require a demonstration flight and allowed for low-altitude maneuvers without verified competency.
- The pilot's initial aerobatic training did not meet minimum requirements, and the certification process was compromised by the close relationship between the instructor and the student.