What was found
DURING HEAVY MAINTNENANCE CENTER UPPER PANEL CORRODED AT RH APPROX STA 1204, XCW 24.5 S-18. AFTER FURTHER EVALUATION BOEING CERTIFIED THE BLENDED OUT AREA AS A PERMANENT REPAIR AND BEEN COMPLETED WITH ALL THE REQUESTED PROVISIONS AT RH APPROX. STA 1204, XCW 24.5, S-18 ON CENTER UPPER PANEL IAW MD-11 BOEING MESSAGE: WGN-WGN-25-0035-04C. THE AIRCRAFT WAS APPROVED FOR RETURN TO SERVICE.