What was found
DURING OP 15 MAINT CHECK ON THE AFT FUSELAGE, LONGERON 20L TO 21L, STA 965, THE TOP AFT CORNER OF THE PRESSURE OUTFLOW CONTROL VALVE CUTOUT HAD CORROSION, 4 INCH BY 5. REPLACED THE LT FUSELAGE SKIN FROM STA 784 TO 996, LONGERON 18 TO 26L, PER DRAWING 5911423.