What was found
DURING HEAVY MAINTENANCE UPPER PANEL CORRODED AT RH APPROX STA 1205, XCW 4.0 AS 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 CENTER WING UPPER PANEL APPROX STA 1205, XCW 4.0 AT S-18 IAW MD-11, BOEING MESSAGE: WGN-WGN-25-0035-04C. THE AIRCRAFT WAS APPROVED FOR RETURN TO SERVICE.