As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) WHILE IN CRUISE, THE NR 1 ENGINE TACHOMETER FAILED, THE FLIGHT CONTINUED TO ITS DESTINATION WITHOUT PROBLEMS. POST-FLIGHT INSPECTION FOUND THE TACHOMETER DRIVE SHAFT SHEARED. THE TACHOMETER WAS REPLACED AND THE AIRCRAFT RETURNED TO SERVICE.