What happened
On February 26, 2021, a local flight departing from Maillen Airfield (EBML) ended in a fatal accident. The pilot-owner was operating a Chickinox Kot Kot 3AA for a non-commercial, local mission. After taking off from runway 27, witnesses observed the aircraft climbing with an unusually low rate of climb. The aircraft then performed a left-hand U-turn to return toward the airfield. While flying over a wooded area, the aircraft's left wing dropped, causing the plane to pitch downward and fall vertically into the trees. The impact destroyed the aircraft. The pilot, who was the sole occupant, was found outside the wreckage; investigators determined the pilot was ejected from his seat because the safety harness had opened during the crash.
The investigation
AAIU(Be) investigators examined the aircraft's condition and the pilot's recent activities. The inquiry focused on recent maintenance performed by the pilot-owner on the tail section of the aircraft. The investigation also looked into the meteorological conditions, noting a crosswind perpendicular to the runway, and reviewed the pilot's medical fitness and the installation of critical flight systems.
Findings
- Recent maintenance work on the tail section included the replacement of parts and adjustments to the elevator controls that did not follow manufacturer instructions.
- Improper installation and rigging of the elevator control cable likely made the aircraft difficult to handle, contributing to the poor climb performance.
- A crosswind of 6 to 9 knots may have further complicated the aircraft's controllability during the departure.
- The safety harness was found to be improperly secured, which allowed the pilot to be ejected upon impact.
- There was a lack of strict medical examination requirements for pilots holding foreign licenses but operating ultralight aircraft within Belgian airspace.