What was found
(AIRCRAFT NOT GROUNDED) (DEFECT DISCOVERED DURING AC HEAVY MX VISIT) NOSE FWD FUSELAGE CABIN FLOOR STRUCTURE, RAIL FOUND CORRODED AT Y503.2 FR16 AREA / NOSE FWD FUSELAGE CABIN FLOOR STRUCTURE, RAIL BTW FR12-16 AND Y503.2 REPLACED AS PER SRM 51-72-11-911-001 REV.158. "