What was found
FRAME AT FS 364.00 CORRODED BETWEEN STGR 25L TO 25R. C-CHECK RO 9/5/2020. REMOVED COMPONENTS AS REQUIRED FOR ACCESS, REMOVED DAMAGED LOWER FRAME SECTOR. INSTALLED A NEW LOWER FRAME SECTOR AND SAME SERVICEABLE SPLICE PLATES AT FS 364.00, IAW CRJ 200 SRM AND BOMBARDIER DWG. REINSTALLED ALL COMPONENTS REMOVED FOR ACCESS WITH ALL OPS CHECKS GOOD. PRESSURIZATION CHECK GOOD. M-337 ATTACHED AND TASK CARD COMPLETED, WEIGHT AND BALANCE NOT AFFECTED.