As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(B737-53-3-0711) MAIN CABIN FLOOR SUPPORT INTERCOSTAL UPPER SURFACE IS CRACKED AT THE FLOOR BOARD FASTENER HOLE STA 312 AND 328 AT APPROX LBL46. BLENDED OUT INTERCOSTAL, FOUND 100% OUT OF LIMITS. REMOVED, LOCATED AND DRILLED NEW INTERCOSTAL AND INSTALLED AT M/C BS312 AND BS328 LBL46 IAW BDWG 141A5400 REV-, SRM 51-40-02 AND SRM 53-10-15.