What was found
EMBRAER HAS RECEIVED REPORTS ABOUT CORROSION ON THE WING-TO-FUSELAGE FAIRING ATTACHMENT (STRAP AND RIB) AT FRAME 45. INVESTIGATION HAS REVEALED THAT WATER ACCUMULATION IN THE WING-TO-FUSELAGE FAIRING REGION IS CAUSING THE CORROSION. THIS ISSUE IS USUALLY FOUND DURING HEAVY CHECK, RESULTING IN UNSCHEDULED MAINTENANCE, TO REPAIR (BLEND-OUT) OR REPLACE THE AFFECTED PARTS. IN ORDER TO DRAIN THE ACCUMULATED WATER IN THIS REGION, EMBRAER ISSUED SB170-53-0114 TO PROVIDE INSTRUCTIONS TO REWORK THE WING-TO FUSELAGE FAIRING RIB SUPPORTS. THE EXPECTED BENEFIT OF THIS MODIFICATION IS TO PREVENT UNSCHEDULED MAINTENANCE BY ELIMINATING THE POTENTIAL CORROSION ON THE WING-TO-FUSELAGE FAIRING SUPPORTS AT FRAME 45. THIS EO IS BEING ISSUED TO PROVIDE INSTRUCTIONS TO ACCOMPLISH EMBRAER SB170-53-0114, WHICH REWORKS THE WING-TO FUSELAGE FAIRING RIB SUPPORTS AT FRAME 45. THE ACCOMPLISHMENT INSTRUCTIONS OF THIS EO WERE DERIVED FROM EMBRAER SB170-53-0114; THEREFORE, A COPY OF THIS SB IS NOT NEEDED TO ACCOMPLISH THIS EO. COMPASS ENGINEERING HAS CLASSIFIED THIS MODIFICATION AS A MINOR ALTERATION.W.O.#2778898