As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING HEAVY CHECK MAINTENANCE FOUND INTERNAL FUSELAGE, CENTER SECTION III, CORROSION ON FLOOR SUPPORT SHEAR PLATE BETWEEN FR87-88 AND BETWEEN RH/LH IB SEAT TRACKS. CORRODED FLOOR SUPPORT SHEAR PLATE BETWEEN FR87-88 AND BETWEEN RH/LH IB SEAT TRACKS REPLACED WITH NEW IAW SRM 51-42-01.