What was found
MCN - MAJOR REPAIR - DURING C-17 CHECK CORROSION WAS FOUND ON FLOORBEAM AT BS 993, LBL 15 TO LBL 20.70. MAINTENANCE REMOVED CORROSION AND FOUND MATERIAL LOSS TO BE OUT OF LIMITS; REMOVED DAMAGED SECTION OF FLOORBEAM AT BS 993, LBL 15 TO LBL 20.70; FABRICATED A NEW REPLACEMENT SECTION OF FLOORBEAM IAW DWG 65C32677; INSTALLED REPAIR PARTS IAW B737-300 SRM 51-40-02, PARA. 7D2, AND 7D6.