What happened
On 31 December 2021, an Air Tractor 502A, registration ZS-XBX, was performing agricultural spraying operations at a private farm (6F12) in the Hartswater region of the Northern Cape. The flight, conducted under visual flight rules, was part of a scheduled mission to spray crops before proceeding to the Welkom area.
While the pilot was executing a right-hand positioning turn to align with the crop rows, the aircraft's left wing struck an 1ob 11-kilovolt powerline. The impact was severe enough to sever both conductors of the line, which were positioned approximately 6.3 metres above the ground. Following the collision, the pilot successfully navigated the aircraft back to the Hartswater private airstrip and landed safely on the gravel runway. There were no injuries to the pilot, though the aircraft suffered substantial damage.
The investigation
An examination of the ZS-XBX revealed significant structural damage to the left side of the aircraft. The powerline had sliced through the outboard and inboard sections of the left-wing leading edge, extending from the fuel cap toward the cockpit. Additional damage was noted on the wing spar, the windshield, the windscreen frames, the aircraft's antennae, and the tail section. The left-side spray boom and its hangers were also broken.
Investigators confirmed that the pilot was experienced, holding a valid commercial license with an agricultural rating, and was familiar with the specific farm layout, having operated there two days prior. The operator's procedures permitted flying at the altitude used, provided the operation did not pose a hazard to persons or property on the ground and was conducted over a non-populous area.
Findings
- The primary cause of the accident was the collision between the aircraft and a powerline during a positioning turn.
- The aircraft was operating in accordance with established agricultural flight procedures.
- The pilot was performing a routine maneuver at a location previously visited within the same week.