What happened
The accident occurred while a helicopter was maneuvering to pick up a bundle of Christmas trees lying on the ground. As the aircraft approached the load, the external load hook became entangled in the bundle. When the hook pulled loose from the trees, it rebounded upward directly into the path of the main rotor blades.
The impact caused significant damage to the rotor blades. This mechanical failure resulted in an uncontrolled descent of the helicopter into the terrain. The sequence of events highlights the hazards associated with external load operations near ground obstacles.
The investigation
Examination of the wreckage revealed that the main rotor blades had sustained damage consistent with striking a foreign object. The external load hook was found in a position indicating it had rebounded from the ground load into the rotor disk area. No other mechanical failures were identified prior to the impact.
Findings
The primary factor in this accident was the entanglement of the external load hook in the Christmas tree bundle. The subsequent rebound of the hook into the main rotor blades caused the loss of control. The pilot's maneuvering to pick up the load placed the hook within close proximity to the ground-based obstacle, creating a hazardous situation.
Safety message
Operators conducting external load operations must ensure that the hook path is clear of ground obstacles. Proper planning and awareness of the hook's trajectory relative to the load are essential to prevent entanglement and potential damage to critical aircraft components.