The Australian Transport Safety Bureau (ATSB) has revealed that a helicopter pilot strayed from usual protocol for unknown reasons before crashing near OZ Minerals’ Carrapateena copper-gold mine in South Australia.
The accident occurred in 2019 when the pilot was undertaking helicopter powerline stringing from the Mount Gunson South substation to the Carrapateena mine.
This was preceded by the pilot’s return to the airport after the first take off due to a warning light in the cockpit.
The pilot then flew to a refuelling point for a final briefing for workers who were involved with the helicopter operations.
A ground crew member was briefed by the pilot on how to connect the draw wire to the helicopter as they had not previously performed the task.
During the stringing operations, witnesses reported that the helicopter had collided with the pole and hit the ground below.
Ground crew came to provide assistance, remove the pilot from the helicopter and extinguish a small post-impact fire.
Emergency services and paramedics from the mine site confirmed that the helicopter pilot had received fatal injuries.
The ATSB investigation has revealed the taught stringing methodology was adjusted for unknown reasons, and placed the helicopter at low level near the powerline poles which increased the risk of collision.
The low level also created more dust which, combined with the sun and position of the craft, reduced the pilot’s visibility of the pole.
To avoid a similar event from occurring, the ATSB has expanded the supervision time for pilots as part of initial training of specialist tasks.
It has also introduced consolidation flight checks at key points for pilots who are recently authorised to perform specialist tasks, and extended the time that pilots are mentored by an experienced pilot in specialist tasks.
The pilot that perished in the crash was an experienced deputy chief pilot with nearly 6500 flight hours.
The ATSB has emphasised that experience alone cannot prevent accidents from occurring in high risk activity, stating that decision making and experience are not linked.
“Using pilot experience as mitigation for potential operational risks is inadvisable. If the risks are unacceptable for a qualified and competent pilot, there should be no reason for an experienced pilot to accept them,” the ATSB stated
“The investigation also highlights the value of direct supervision of pilots who have recently been trained in a new task.”