As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
8/11/08 INSTALLED YAW DAMPENER. 10/06/08 - CUSTOMER COMPLAINT OF INDUCED YAW WHEN ENGAGING AUTO PILOT. REMOVED YAW DAMPENER AND FOUND UNIT CONTAMINATED WITH WATER. UNIT IS MOUNTED WITH DRIVE SHAFT UP AND WITH NO DRAIN, THIS PROVIDES FOR WATER TO BE TRAPPED IN THE SERVO. RECOMMEND SEALING THE UNIT BETTER OR PROVIDING DRAINS FOR UNIT. (K)