As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING FLIGHT 3052 MAIN AILERON TRIM RUNAWAY. LEFT WING HAD STRONG DOWNLOAD FORCES. TRIM INDICATOR INDICATED FULL-UP ON INDICATOR, UNABLE TO NEUTRALIZE FORCES WITH MAIN TRIM STANDBY TRIM WORKED. AIR RETURN TO RHI. MAINTENANCE FOUND LT AILERON TRIM ACTUATOR TO BE FAULTY. REMOVED AND REPLACED LT AILERON TRIM ACTUATOR P/N D97648, S/N OFF 96H19190, S/N ON 91K1575-127 IAW SAAB MM 27-12-10. OPS CHECK GOOD.