What was found
THIS EO IS BEING ISSUED TO PROVIDE INSTRUCTIONS TO ACCOMPLISH THE PERMANENT REPAIR OF CORROSION DAMAGE TO THE AFT CABIN FLOOR STRUCTURE RT AFT SEAT TRACK, PN 170-86082-003 AT FRAME 84 & Y=+260. THE APPROX DAMAGE DIMENSIONS ARE AS FOLLOWS, 4.40 INCHES X 1.0 INCH TO A MAX DEPTH OF .045 INCH DEEP. BECAUSE THE FLOOR TRACK IS A PSE, ACCOMPLISHMENT OF THIS EO HAS BEEN CLASSIFIED AS A MAJOR REPAIR DUE TO STRENGTH RESTORATION. THIS IS NOT CLASSIFIED AS FCS, BUT WILL REQUIRE FOLLOW UP INSPECTIONS. EO E175-53MR-253.1 WILL BE ISSUED TO ACCOMPLISH THE FOLLOW UP INSPECTIONS IAW ANAC DER FORM ATTACHED. REF 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. ACCOMPLISHMENT OF THIS MAJOR REPAIR WAS ON EO E175-53MR-253 UNDER WO 2048648.