As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
**WHILE AIRCRAFT WAS OUT OF SERVICE FOR HEAVY CHECK** MAINTENANCE FOUND 633-23 FWD FUSELAGE WET AREA FLOOR SRUCTURE FR17/18/19 LHIB SEAT TRACK BEAM UPPER FLANGE FOUND CORRODED. REPLACED TRACK BEAM UPPER FLANGE IAW SRM 53-10-10 AIRCRAFT REMAINS OUT OF SERVICE FOR HEAVY CHECK COMPLETION.