What happened
On 1 April 2025, a Thrush S2R-H80 aircraft, registration ZS-IOG, was performing agricultural spraying operations near Komatipoort, Mpumalanga. The flight, conducted under Part 137 regulations, began from a private airstrip near the Komati Sugar Mill. After completing 50 successful spray runs, the pilot was executing a right-side turn to prepare for the final application at approximately 80 feet above ground level. During this maneuver, the engine experienced a sudden drop in power and a significant loss of thrust.
In response to the power loss, the pilot immediately advanced the throttle to maximum, but the engine failed to recover. To mitigate the risk, the pilot jettisoned the remaining chemical payload and performed an emergency forced landing in a grass field. While the aircraft remained upright, the tail gear assembly broke during the impact, causing substantial damage to the airframe. The pilot escaped the wreckage unassisted and sustained no injuries.
The investigation
SACAA AIID investigators examined the aircraft and its maintenance history to determine the cause of the engine failure. Post-accident inspections by engineers revealed that the engine and propeller were undamaged, with no evidence of leaks or contamination in the fuel. However, during subsequent inspections at a maintenance facility, investigators found that the engine fuel filter was dry and the fuel control unit (FCU) was empty.
Technical tests performed on the fuel showed no presence of water or bacterial growth. Ground run tests confirmed that the engine was otherwise functioning within normal parameters. The investigation also reviewed the aircraft's maintenance records, which showed the aircraft had undergone a 100-hour inspection recently and had no outstanding mechanical defects or unaddressed airworthiness directives.