As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING MAINTENANCE BASE VISIT THE LEFT FLOORBEAM AT FRAME 280 WAS FOUND TO BE CORRODED. THE AIRCRAFT WAS REMOVED FROM SERVICE. REMOVED AND REPLACED THE LEFT FLOORBEAM AT FRAME 280 IAW EO CR-53MR-134R1. THE AIRCRAFT WAS RETURNED TO SERVICE.