As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
WOA8198/01 BGR/BGR AIR TURNBACK. ABOUT 10 MINS AFTER DEPT, HYD 3 OFF ALERT DISPLAYED (FLUID LOSS). RETURNED TO BGR WHEN SLATS WERE EXTENDED, HYD 3 FAIL ALERT DISPLAYED 0 FLUID. FOUND NR 1 STAB TRIM MOTOR LEAKING. REMOVED AND REPLACED STAB TRIM MOTOR. LEAK AND OPS CK OK.