What was found
WHILE AIRCRAFT WAS OUT OF SERVICE FOR HEAVY CHECK, MAINTENANCE FOUND LEVEL 2 CORROSION AT AFT WET AREA, RT INBOARD FLOOR BEAM FR 89 TO FR 90. RT INBOARD INTERCOSTAL/FLOORBEAM WAS REMOVED AND REPLACED IAW SRM 51-41-01 AND 51-43-03. AIRCRAFT REMAINS OUT OF SERVICE FOR HEAVY CHECK COMPLETION.