What was found
CREW REPORTED STABILIZER TRIM RUNAWAY ON DEPARTURE CLIMBOUT. CREW RETURNED TO FIELD AND LANDED WITHOUT INCIDENT. AFTER DEBRIEF WITH FLIGHT CREW, IT WAS DETERMINED THAT STABILIZER TRIM MOVEMENT OCCURRED 2 SECONDS AFTER FLAPS SELECTED UP, WHICH IS NORMAL OPERATION OF FLAP COMPENSATION TRIM. MAINTENANCE PERFORMED OPS TESTS IAW AMM. OPERATIONAL TESTS GOOD. NO DEFECTS NOTED. AS A PRECAUTIONARY MEASURE, MAINTENANCE R & R HORIZONTAL STABILIZER MOTOR CONTROL UNIT IAW AMM. ACFT RELEASED FOR SERVICE.