As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
MCN - MAJOR REPAIR - DURING C-18 CHECK EXFOLIATION CORROSION WAS FOUND IN TWO PLACES ON UPPER SURFACE OF INTERCOSTAL AT BS 294.5, LBL 12. MAINTENANCE REMOVED CORROSION, MATERIAL LOSS OUT OF LIMITS, REMOVED INTERCOSTAL AT BS 294.5, LBL 12; FABRICATED A NEW REPLACEMENT INTERCOSTAL; INSTALLED REPAIR PART IAW B737-300 SRM 51-40-02 FIG 12 PG 1.