As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) AFTER TAKE OFF, THE FLIGHT CREW REPORTED RUDDER TRIM INOPERATIVE. QRH PERFORMED. RETURNED TO DEPARTURE AIRPORT FOR LANDING WITHOUT FURTHER INCIDENT. MECHANIC RESET THE RUDDER TRIM CB THEN TESTED TRIM, NO MOVEMENT. RUDDER TRIM PANEL REMOVED AND PANEL WAS (TAPPED) THEN RE-INSTALLED, THEN TRIM OPERATION WAS NORMAL. RUDDER TRIM SWITCH REPLACED AS PRECAUTION.