What was found
DURING 763CK'S C4 CHECK IN OSC, KALITTA MAINTENANCE FOUND CORROSION ON THE UPPER SKIN PANEL #1 (P/N 112T3301-1) UNDER PANEL #9 (P/N 113T1609-1), AFT OF THE REAR SPAR, WSTA 349.7 - 359. THE CORROSION WAS BLENDED AND FOUND OUT OF LIMITS PER SRM 57-20-01, ALLOWABLE DAMAGE. IT WAS DETERMINED THAT NO SRM REPAIRS COVER THIS AREA. ABX HAS CONTACTED FVCI TO PROVIDE A FAA-DER APPROVED REPAIR. THE PURPOSE OF THIS REA IS TO AUTHORIZE AND DOCUMENT THE ACCOMPLISHMENT OF REF/A/, APPROVED REPAIR.ANALYSIS: WING UPPER SKIN PANEL #1 IS CONSIDERED FCS STRUCTURE PER SRM 51-00-04, GENERAL, TABLE 4, 767-FCBS-57-021. MAJOR REPAIR. ACCOMPLISHED REPAIR AT LT WING UPPER SKIN APPROX WS 314 IAW FVCI EO 25089-5.