Accident Description
A helicopter was approaching a pick-up area for a load of Christmas trees. The approach path required crossing a tree-lined ridge and descending into a basin. The pilot reported that during deceleration, a loud bang was heard. Warning horns and lights then activated as the helicopter turned left and rolled right. The aircraft subsequently collided with trees and terrain.
A witness on the ground observed the helicopter descending. According to the witness, the long line (load line) swung forward and rose straight up in front of the cabin. Immediately thereafter, the main rotor blades separated, and the helicopter began to descend. The witness heard a loud screaming sound, followed by a loud explosion, and saw the helicopter break apart in mid-air.
The cabin continued in its direction of travel, inverted, and collided with trees and terrain. The tail section separated and impacted the ground near where the witness was standing.
Physical Evidence
Post-accident examination revealed cable marks on one main rotor blade and one tail rotor blade. The load line had been severed from the helicopter, and the load line hook exhibited severe impact damage signatures.
Findings
The facts indicate that the load line contacted the main rotor and tail rotor blades, leading to rotor separation and subsequent in-flight breakup.