As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS GROUNDED: AFTER TAKE OFF, AT 9500FT AND 250KIAS, ELECTRIC STAB TRIM MAKE A CLUNKY NOISE AND BECAME UNRESPONSIVE. MANUAL TRIM WAS UNRESPONSIVE TOO. DECESION MADE TO RETURN TO MIA. EMERGENCY DECLARED AND LANDED OVERWEIGHT WITHOUT INCIDENT. LANDING MADE AT 140,000LBS. AND FLAPS 15. MAINTENANCE FOUND CONTROL WHEEL STAB-TRIM CHAIN BROKEN AND REPLACED CHAIN FOR THE STAB TRIM IAW AMM 27-41-00.