What was found
DURING ROUTINE C-CHECK INSPECTION, CORROSION WAS BLENDED BEYOND SRM LIMITS. THE EXTERIOR PLATING AT STATION 530-550 BETWEEN LONGERONS 33 RT AND 36. DAMAGE WAS REMOVED BY CUTOUT, ADDING A FILLER AND EXTERNAL DOUBLER. REPAIR ACCOMPLISHED IAW DRAWING HSE27-53-168, WHICH IS FAA DER APPROVED AND EO 53-DC8-157. (W)