What happened
During a routine cattle herding operation conducted over uneven and difficult terrain, the aircraft experienced a sudden and complete loss of anti-torque and directional control. This mechanical failure was traced to a broken tail rotor cable. Despite the pilot's immediate adherence to published emergency procedures for such failures, the aircraft became uncontrollable.
The pilot initiated an autorotative descent in an attempt to land safely. However, during this descent, the helicopter struck a tree. The impact caused the aircraft to roll to its left side before it ultimately struck the ground with significant force.
The investigation
The investigation focused on the mechanical failure that precipitated the accident. Examination of the aircraft revealed that the tail rotor cable had failed, leading directly to the loss of directional control. No other mechanical anomalies were cited as contributing factors in the immediate sequence of events.
Findings
The primary factor in this accident was the structural failure of the tail rotor cable. The pilot's actions were consistent with standard emergency protocols for anti-torque failure. However, the terrain and the nature of the operation left little margin for error during the subsequent autorotation.
- Tail rotor cable failure
- Loss of directional control
- Impact with a tree during autorotation
- Left-side ground impact