As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
THE ROLL SERVO MOUNT CLUTCH SLIP SETTING IS 28 POUNDS. IT WOULD NOT SLIP AT 70 POUNDS. DIRT AND POSSIBLE OIL OVER YEARS SET UP CLUTCH. LOSS OF FLIGHT CONTROL IS POSSIBLE. SUBMITTER RECOMMENDS PERIODIC INSPECTIONS OF ALL 1,000 AUTOPILOT SLIP CLUTCHES. NOTE: CLUTCH SLIP DISCS WERE REPLACED FOR REPAIR.