As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
MCN - DURING C11 CHECK DISCOVERED CORROSION, LEVEL 2 EXFOLIATION, ON INTERCOSTAL BS 1500 TO BS 1520 BETWEEN STR 29L AND 29R. MAINTENANCE REMOVED CORROSION. CORROSION WAS OUT OF SRM LIMITS IAW BOEING 757-200 SRM 53-60-04-1A FIG 101. FABRICATED INTERCOSTAL IAW BOEING 757-200 SRM 51-40-01-OG FIG 7 AND DWG 146N545I REV. C. INSTALLED FABRICATED INTERCOSTAL AT BS 1500 TO BS 1520, BETWEEN STR 29L AND 29R IAW BOEING 757-200 SRM 51-40-02-OG FIGS 3 AND 8.