As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) THE ENGINE EXPERIENCED TORQUE FLUCTUATIONS IN CRUISE FOLLOWED BY AN UNCOMMANDED REDUCTION IN PROPELLER SPEED TO 12 PERCENT. THE PILOT SHUT THE ENGINE DOWN AND DIVERTED THE FLIGHT. MFG WILL MONITOR THE INVESTIGATION OF THE INCIDENT AND WILL SUPPLIMENT THIS REPORT TO PROVIDE ROOT CAUSE, ONCE ESTABLISHED.