What happened
On 7 June 2015, a solo training flight involving a Windlass Trike, registration ZU-SBMS, ended in a fatal accident at Kroon airfield in Gauteng. The flight began as a dual instruction session, which concluded successfully after several circuits. Following the instructor's approval, the student pilot proceeded with solo circuit training.
During the second circuit, the aircraft began exhibiting unstable behavior. While on the cross-wind leg for Runway 11, the microlight began oscillating between left and right turns. The instructor, monitoring the flight from the ground via radio, observed the aircraft's altitude and power settings fluctuating continuously. Despite instructions to stabilize the aircraft and maintain the circuit pattern, the student pilot's control became increasingly erratic. As the aircraft approached the base leg, it entered a steep bank that eventually reached an almost inverted position. The aircraft subsequently struck a tree, and the resulting impact was followed by a severe post-impact fire that destroyed the wreckage. The pilot sustained fatal injuries.
The investigation
SACAA AIID investigators examined the flight history, aircraft maintenance, and the wreckage. The investigation established that the student pilot had a total of 36.8 flying hours, with 27.5 hours specifically on this aircraft type. The pilot's training had recently been interrupted by a three-month hiatus, and the flight occurred after a week of poor weather had prevented flying.
Technical examination of the Windlass Trike revealed no mechanical anomalies or technical defects that could account for the crash. The investigation also noted that while the owner had applied for a Training Authority to Fly, the aircraft was officially operating under a Private Authority to Fly at the time of the accident; the specific training authorization was only issued the day after the occurrence.
Findings
- The primary cause of the accident was the loss of control in flight while the pilot was maneuvering for the left base leg.
- The pilot experienced significant disorientation, characterized by uncorrected roll and yaw oscillations and unstable pitch movements.
- The student's relative inexperience with this specific aircraft type contributed to the inability to manage the developing oscillations.
- The aircraft's authority to fly was limited to private use only at the time of the accident.