As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING DESCENT FROM RDU TO ATL, THE FLIGHT CREW NOTICED THE NUMBER THREE ENGINE THRUST REVERSER WAS VERY SLOW TO STOW AFTER DEPLOYMENT. THE FLIGHT CONTINUED TO ATL FOR AN UNEVENTFUL LANDING. MAINTENANCE INSPECTED THE ENGINE WHICH REVEALED A PORTION OF THE NUMBER THREE ENGING INBOARD THRUST REVERSER TRANSLATING COWLING HAD DEPARTED FROM THE ENGINE. MAINTENANCE REPLACED THE INBOARD THRUST REVERSER HALF IN ACCORDANCE WITH THE MAINTENANCE MANUAL. THE AIRCRAFT WAS RETURNED TO SERVICE.