As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
RAP - FLT 434 - THE RIGHT ENGINE RPM WAS ERRATIC IN FLIGHT. THE PROBLEM COULD NOT BE DUPLICATED ON THE GROUND. THE TACH GENERATOR WAS REMOVED FOR INSPECTION AND THE SHAFT WAS LOOSE FROM A WORN ROLE PIN THE BACK. THE TACH GENERATOR WAS REPLACED AND ENGINE RUN PERFORMED. THE AIRCRAFT WAS RELEASED. (M)