As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) BEFORE FIRST FLIGHT OF DAY, AIRCRAFT IN HOVER. CLUTCH LIGHT FLICKERING AND PILOT HEARS GROWLING AND FEELS VIBRATION. INSPECTION FOUND CENTER HUB IN THE FAN HAD CRACKED COMPLETELY AROUND CAUSING THE CENTER HUB BOLTS TO LOOSEN OFF. THERE WAS ALSO A LOT OF METAL TRANSFER BETWEEN FAN WHEEL AND TAPERED SHAFT OF BEARING ASSY (P/N C007-5).