As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ENGINE EXPERIENCED AN N2 OVERSPEED IN FLIGHT. PILOT REGAINED CONTROL WITH THROTTLE AND LANDED AIRCRAFT WITHOUT FURTHER INCIDENT. REMOVAL OF GOVERNOR FOUND INPUT SHAFT SHEARED WITH AN APPARENT INTERNAL CONTACT OF THE FLYWEIGHT TO THE GOV HOUSING.