What happened
On 19 October 2006, a Piper PA-28-140, registration ZS-EXM, departed Kimberley Aerodrome on a domestic charter flight. The mission involved inspecting high-tension power lines, with a surveyor on board providing guidance on altitude and maneuvering to facilitate photography.
While flying at a low altitude over Spitskop farm, the aircraft entered a turn. An eyewitness observed the plane performing a maneuver as if the pilot were focusing on ground features, after which the aircraft suddenly descended. The aircraft struck the ground, skidded approximately 200 meters, and eventually collided with a tree, causing the airframe to roll over. The impact was so severe that the occupants were ejected from the aircraft, and the plane was destroyed. Both the pilot and the passenger sustained fatal injuries.
The investigation
SACAA AIID investigators examined the wreckage and the engine components. A detailed teardown of the Lycoming engine by an approved maintenance organization found no mechanical anomalies, and all primary flight controls—including the ailerons, rudder, and elevator—were found to be in good working order and properly attached.
The investigation also reviewed the pilot's credentials, noting they held a valid commercial license and medical certificate. Meteorological data confirmed that while the sky was relatively clear, there were significant winds of approximately 15 knots from the northeast. Investigators also looked into the operational environment, noting that the surveyor was providing active instructions regarding flight path and altitude to assist with the inspection task.
Findings
- The primary cause of the accident was an aerodynamic stall occurring during a turn.
- In an attempt to recover from the loss of altitude, the pilot pitched the nose up, which increased the angle of attack and further reduced airspeed.
- The low altitude of the maneuver left insufficient margin for the pilot to recover before impact.
- Contributing factors included the aircraft's low-level flight and the presence of windy conditions during the maneuver.