What was found
WHILE AIRCRAFT WAS IN FOR HEAVY CHECK, MAINTENANCE REPORTED LEVEL 2 CORROSION ON THE FLOORBEAM AT FR 14. MAINTENANCE REMOVED AND REPLACED SEAT TRACK AT FR 14 IAW SRM 51-40-02, 51-40-03, 51-41-02, 51-41-01 & 51-43-04. AIRCRAFT IS CURRENTLY STILL OUT OF SERVICE FOR HEAVY CHECK COMPLETION.