What happened
The pilot was requested by the operator to fly the helicopter as part of an arrangement prior to the completion of a leaseback agreement with the owner. During an initial attempt at an air taxi to a helipad, the aircraft experienced a ground resonance event that caused oscillations, forcing the pilot to abort the maneuver.
Following this first event, the oleo struts showed unequal extension, with one strut being low and another appearing flat. Approximately 18 days later, after the pilot had been informed that the struts had been repaired, the owner was operating the aircraft for a planned air taxi to a helipad. During this second attempt, the helicopter again encountered a ground resonance event. The resulting oscillations were so severe that they led to the destruction of the aircraft. The pilot reported that he attempted to mitigate the vibrations by lowering the collective and decreasing the throttle when the oscillations began.
The investigation
Investigators were unable to obtain the maintenance records or the specific components of the helicopter for further testing.