What was found
MCN - MAJOR REPAIR - DURING C-03 CHECK CORROSION WAS FOUND ON UPPER AND LOWER SURFACE OF CABIN FLOORBEAM AT FR 66+7, Y919. MAINTENANCE REMOVED CORRODED FLOORBEAM AT FR 66+7, Y919; FABRICATED A NEW REPLACEMENT FLOORBEAM; INSTALLED REPAIR PART IAW A320 SRM 51-42-11, PG. 6-7, AND SRM 51-49-00, PG. 5-6, TABLE 1.