As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING MAINTENANCE BASE VISIT FOUND THE LEFT CENTER AISLE BEAM RUNNING ALONG Y=-479, VERTICAL SIDE TO HAVE CORROSION AT APPROXIMATELY AFT OF FRAME 49 ABOVE CARBON FIBER CROSS MEMBER. THE AIRCRAFT WAS REMOVED FROM SERVICE. REPAIRED BEAM AT FRAME 49 IAW ETD-2011-145/03560. THE AIRCRAFT WAS RETURNED TO SERVICE.