As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING NORMAL FLIGHT PILOT EXPERIENCED ABNORMAL VIBRATIONS. THE PILOT INITIATED AN EMERGENCY LANDING AND LANDED WITH THE GEARS UP IN A FIELD. MAINTENANCE PERSONNEL INSPECTED THE AIRCRAFT AND FOUND THE TIP CAP UPPER SKIN ON MAIN ROTOR BLADE P/N 709-0103-01-109 S/N A5-1641 SEPARATED FROM THE LEADING EDGE TO THE TRAILING EDGE. THE AIRCRAFT WILL BE TRANSPORTED TO MFG FIELD ON A FLAT BED TRUCK.