As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING CURRENT C CHECK AT KLM FOUND KEEL BEAM BOX WEB UPPER SURFACE ON BOTH LEFT/RIGHT SIDES OF BL 0 CORRODED. CUT AND REMOVED WEB FROM BS 1265 TO 1273. PERFORMED OPEN HOLE HFEC INSPECTION OF REMOVED FASTENER HOLES IN REPAIR AREA. NO ADDITIONAL CRACKS/CORROSION FOUND. FABRICATED REPLACEMENT WEB AND TWO SPLICE DOUBLERS. INSTALLED PARTS IAW SRM STANDARD PRACTICES.