As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
INSTRUCTOR MADE UNSCHEDULED LANDING IN SAFE AREA AFTER EXCESSIVE NOISE AND VIBRATION FROM ENGINE AREA. FOUND AFT MAIN DRIVE BELT HAD FAILED COMPLETELY AND HAD PUSHED THE FORWARD BELT FORWARD WHERE ONLY ONE SECTION WAS STILL POWERING ROTOR DRIVE SYSTEM. ADDITIONAL DAMAGE TO ENGINE COOLING FAN SHROUD BY ENGINE OIL COOLER. ALL BELTS AND FAN SHROUD TO BE REPLACED. ONE ANTENNA CONNECTOR TO BE RELACED. THIS IS NOT A CHARTER AIRCRAFT.