What was found
WHILE IN FOR SI CHECK, MAINTENANCE REPORTED WHILE WORKING ON CUSTOMER CARD NR 437378, FOUND HORIZONTAL CHORD AT STA 294.5, WL 181, LBL 17, AND RBL 4-25, TO HAVE CORROSION. OUT OF LIMITS. REMOVED AND REPLACED FUSELAGE CHORD AND HORIZONTAL CHORD IAW SRM 51-30-2, 51-20-4, 51-30-5.