What was found
DURING S90M CHECK OF DATUM A/C, FOUND CORROSION, UPPER SURFACE OF FRONT SPAR LOWER CHORD OF LT WING AT STA XRS 509.2. LT WING (STA. XRS 115-601) AND RT WING (STA. XRS 73-477) UPPER SKIN. T/E ALUMINUM STRIP OF RUDDER THAT HAD PENETRATED THROUGH THE ENTIRE THICKNESS.4. NR 1-NR 2 ON LOWER WING SURFACE OF LT WING AT STA XRS=546.5. FUSELAGE FRAME LOWER TEE (P/N:9912246-115). THE CORROSION LOCATED STA 1437, L29R-L26R.6. PFM MAJOR REPAIR .