As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING C-4 CHECK INSPECTION, FOUND FS 1660 BULGE IN SKIN BELOW LEFT HAND AFT ENTRY DOOR. REMOVED CORROSION AND TREATED THE AREA IAW SRM 51-1-8 AND INSTALLED DOUBLER REPAIR IAW SRM 53-2-0 FIGURE 18. C-4 CHECK WORK CARD 3097, NON-ROUTINE TASK CARD NR 87246.