As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING MAINTENACE BASE VISIT FOUND THE LEFT CABIN FLOORBEAM AT FRAME 57 TO BE CORRODED. THE AIRCRAFT WAS REMOVED FROM SERVICE. REMOVED DAMAGED AREA, FABRICATED AND INSTALLED DOUBLER IAW EO EM-53MR-1712. THE AIRCRAFT WAS RETURNED TO SERVICE.