What was found
MCN - MAJOR REPAIR - DURING C-17 CHECK, CORROSION WAS FOUND ON UPPER AND LOWER SURFACE OF FLOORBEAM UPPER CHORD AT BS 1016, BETWEEN LBL 4 AND LBL 34, WL 208. MAINTENANCE CUTOUT DAMAGE IN FLOORBEAM UPPER CHORD AT BS 1016, FROM LBL 4 TO LBL 34; FABRICATED A NEW REPLACEMENT SECTION OF UPPER CHORD, 2 EACH SUPPORT ANGLES AND STRAPS; INSTALLED REPAIR PARTS IAW B737-300 SRM 53-00-51, FIG 202.