What was found
DURING AIRCRAFT C-CHECK, MAINTENANCE REPORTED CORROSION COMMON TO FLOORBEAM P/N 368-53-16-94157-201 AT STA 1109 AND BL0. CORROSION WAS FOUND IN FLOORBEAM LOWER CHORD, THE ORIGINAL THICKNESS FOUND TO BE .600'', MATERIAL REMAINING AT DEEPEST POINT IS .200'', MATERIAL LOSS IS .400'' FOUND OUT OFF LIMIT IAW 767-200 IAI SUPPLEMENTAL SRM 53-00-51 ALLOWABLE DAMAGE. PERMANENT REPAIR INSTRUCTION WAS PROVIDED. AIRCRAFT REPAIRED AND RETURNED TO SERVICE.