What was found
***WHILE A/C WAS OUT OF SERVICE FOR HEAVY CHECK*** PASSENGER CABIN CF III FLOOR STRUCTURE, CORROSION FOUND AT PNL SUPPORT AREA BTW FR88-89 RBL36". PASSENGER CABIN CF III FLOOR STRUCTURE, PNL SUPPORT REPLACED AT AREA BWT FR88-89 RBL36" IAW SRM 51-43-03 & 51-42-03. A/C REMAINS OUT OF SERVICE FOR HEAVY CHECK COMPLETION.