What happened
On 12 January 2026, a crop-spraying operation in the Free State province resulted in the crash-landing of an Ayres S2D-T34 Turbo Thrush, registration ZS-NMR. The flight, conducted under visual meteorological conditions, began at a private farm airstrip near Verkykerskop.
After successfully completing several spraying cycles using Urea fertiliser, the pilot prepared for a new load of Potassium Sulphate. During the takeoff roll from the potato farm runway, the aircraft failed to achieve a positive rate of climb. In an attempt to mitigate the weight, the pilot activated the hopper dump door to jettison the load. However, the discharge was not rapid enough to prevent the aircraft from impacting a nearby maize field. While the aircraft suffered substantial damage, there were no injuries to the pilot.
The investigation
SACAA AIID investigators examined the weight and balance records and the loading procedures used during the operation. The investigation established that the aircraft's maximum takeoff weight (MTOW) is 6,000 lbs. However, the weight recorded for the final flight was 9,857 lbs, representing a massive overload.
It was determined that the ground crew had loaded two bags of Potassium Sulphate into the hopper instead of one. Although the Potassium Sulphate bags appeared smaller in volume than the previously used Urea bags, both types of bags weighed 1,000kg each. This discrepancy in visual size led to a critical error in the loading process.
Findings
- The aircraft was operating significantly above its maximum certified takeoff weight.
- The extreme weight caused degraded takeoff performance, making a climb impossible.
- The ground crew lacked the necessary situational awareness regarding the weight of the different fertiliser types.
- The pilot was fully licensed with a valid Class 1 medical and significant experience on the aircraft type.