What was found
ATL - DURING CONTRACT MAINTENANCE AT DALA FOR HEAVY C-CHECK. CORROSION DAMAGE WAS FOUND ON THE LOWER WING SKIN CENTER SECTION BETWEEN S-3C AND S-4C ABOVE THE LT PLENUM CHAMBER. CORROSION WAS CLEANED AND A REPAIR SIMILAR TO SRM 57-30-3, FIGURE 10, WAS INSTALLED. DURING FASTENER REMOVAL, 2 FASTENER HOLES ON S-3C WERE DAMAGED, APPROXIMATELY .1250 INCH OF MATERIAL WAS CHIPPED OUT OF THE OUTER SURFACE. THE DAMAGE WAS REMOVED BY COUNTERSINKING THE HOLES. REPAIRS ACCOMPLISHED PER DL ERA 303272-14 AD. ACFT TT, 40,899 HRS. ACFT TC, 21,258. (X)