As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
INITIAL INSPECTION: CORROSION ON INTERCOSTAL BTW FS=333.00 TO FS=349.00 STR 21L AT INTERNAL STRUCTURE OF MAIN AVIONICS COMPARTMENT (E/E) (SM). IN REFERENCE NRC 00084 TASK 900-53-140-300 APPENDIX A ].(TCI:100-09) SUMMARY CORROSION LEVEL 2: INTERCOSTAL BTW FS=333.00 TO FS=349.00 STR 21L AT INTERNAL STRUCTURE OF MAIN AVIONICS COMPARTMENT WAS REPLACED PER SRM 51-42-20-001-001-A01.