What was found
DURING BASIC CHECK, INSPECTION DISCOVERED CORROSION ON THE AFT CABIN LT AFT BEAM, PN 170-65669-003, UPPER FLANGE. REQUESTED A REPAIR & RECEIVED ETD2015-170-119350 WHICH PROVIDES A PERMANENT REPAIR BY INSTALLING A REPAIR DOUBLER USING THE PRINCIPLES OF SRM PART II 53-23-10 REPAIR 02P. THE CORROSION DAMAGE APPROX DIMENSIONS ARE 1.0 INCH X .50 INCH MAXIMUM DEPTH OF .010 INCH DEEP & 2.25 INCHES X 1.25 INCHES WITH A MAXIMUM DEPTH OF .015 INCH DEEP. THIS STRUCTURE IS NOT FCS, BUT REQUIRES FOLLOW UP INSPECTIONS. EO E175-F3MR-234 1 WILL BE ISSUED TO ACCOMPLISH FOLLOW UP INSPECTIONS IAW ETD2015-170-119350 ANAC DER FORM ATTACHED. REF INSPECTION INSTRUCTIONS, TASK 53-23-005-0001, INTERNAL GVI THRESHOLD OF 20,483FC OR 27,242FH, INTERVAL OF 10,133FC OR 13,476FH, IS SUFFICIENT & IS MET USING THE INSPECTION REQUIREMENTS, MPG & MRBR REVISION 11. ENGINEERING HAS CLASSIFIED THIS REPAIR AS A MAJOR REPAIR. ACCOMPLISHMENT OF THIS MAJOR REPAIR WAS ON EO E175-53MR-234 UNDER WO 2004884.