As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
THE BL 0 LONGITUDINAL FLOORBEAM OVER THE CENTER WING WAS FOUND WITH A CRACK IN THE UPPER CHORD AND WEB AT FS 660 AND WITH 4 CRACKS IN THE WEB AT UPPER CHORD ATTACH POINTS AT FS 700. THE CRACKING IS TYPICAL OF BAC S/B 737-57-1210. THE FLOORBEAM WAS REPAIRED AND MODIFIED PER THE REQUIREMENTS OF THE S/B AND DOCUMENTED PER ER/A 380586-14.