As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING A HEAVY MAINTENANCE CHECK IN THE AFT CARGO PIT STA 1841 TO 1964 RT SIDE LOWER CENTER FLOOR TO LOWER SIDE FLOOR Z CHANNEL HAS CORROSION ON ENTIRE LENGTH. REMOVED CORROSION AND WAS FOUND OUT OF LIMITS. REMOVED AND INSTALLED NEW CHANNEL PER SRM 513101.