As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLT 5833 - CLT-MGM - PILOT REPORTED SHORTLY AFTER TAKEOFF FROM CLT, UNCOMMANDED PITCH TRIM ACTUATION. MAINTAINED CONTROL OF THE PLANE USING HIS STANDBY TRIM SYSTEM. MX TROUBLESHOT TO A BAD HSTCU. MAINTENANCE REMOVED AND REPLACED THE HSTCU. OPS CHECKS GOOD. THE AIRCRAFT WAS RETURNED TO SERVICE. (M)