What was found
***WHILE A/C WAS OUT OF SERVICE FOR HEAVY CHECK*** FWD FUSELAGE WET AREA FLOOR STRUCTURE BTW FR 17-20 LBL 11", SEAT BTRACK BEAM UPPER FLANGE FOUND CORRODED. FWD FUSELAGE WET AREA FLOOR STRUCTURE BTW FR12-20 RBL 11 SEAT TRACK REPLACEC IAW SRM 51-41-07, 51-41-02, 51-43-03 & 51-43-04. A/C REMAINS OUT OF SERVICE FOR HEAVY CHECK COMPLETION.