As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
INDICATIONS OF CORROSION NOTED AT WS 231.0 (650BB) ON THE FLAT LANDING SURFACE OF LOWER WING PLANK APPROX 70 PERCENT FULL SCREEN HEIGHT. AREAS MARKED ON ACFT. C/W EC/TC EO 600-57-81, C/W IAW REO 601R-57-21-030 REV G AND FWDED ALL REQUIRED FORMS TO STRUCTURE ENGINEERING.