Incident Overview
A helicopter involved in cranberry harvesting operations experienced a catastrophic failure after a cargo basket was jettisoned. The pilot had previously completed several successful lifts with similar loads into the wind. The accident occurred during the first lift attempt at a new location.
Pre-Accident Sequence
The helicopter was in a hover approximately 12 feet above the ground, positioned forward of the load. The prevailing wind was from a left quartering tailwind direction relative to the helicopter. Ground crew attached a 900-pound cargo basket to a 15-foot sling load line. Once secured, the helicopter moved forward, causing the cargo basket to be dragged along the ground.
Accident Sequence
During the dragging, a loud pop was heard, and a flame approximately one foot long was observed exiting the left exhaust pipe. The cargo basket was dragged into a ditch, prompting the pilot to jettison the load. After release, the helicopter pitched up. The main rotor blades then severed the tail boom, and the main rotor assembly separated from the helicopter. The helicopter fell to the ground and rolled onto its left side.
Post-Accident Examination
Examination of the separated main rotor assembly revealed that it had detached from the main rotor mast below the contact areas for the static stops. No obstructions were found that would have prevented the pilot from departing into the wind.
Contributing Factors
The source does not state a probable cause or identify contributing factors beyond the described sequence of events.