What was found
MCN - DURING C11 CHECK DISCOVERED CORROSION, LEVEL 2 GALVANIC, ON INTERCOSTAL FOOT FORWARD CARGO COMPARTMENT BETWEEN STR 28R AND STR 27R, FROM BS 740 TO BS 760. MAINTENANCE REMOVED CORROSION BETWEEN STR 28R AND STR 27R FROM BS 740 TO BS 760 IAW BOEING 757-200 AMM 51-00-53-2. CORROSION WAS FOUND OUT OF SRM LIMITS IAW BOEING 757-200 SRM 53-00-04-1A FIG 101. FABRICATED INTERCOSTAL IAW BOEING 757-200 SRM 51-30-01 FIG 7. INSTALLED FABRICATED INTERCOSTAL IN FORWARD CARGO COMPARTMENT BETWEEN STR 28R AND STR 27R, FROM BS 740 TO BS 760 IAW BOEING 757-200 SRM 51-40-02-OG FIG 8, 14, 3.