What was found
DURING HEAVY MAINTENANCE, CHAFING MARKS WERE REPORTED AT THE LH WING INBOARD AFT FLAP (PN 190-38006-403/ SN 00009) UPPER SKIN AT RIB 1A. SEE REF /1/ ETI FOR DETAILS. THE MARKS ARE 2 PLIES DEEP CAUSING DAMAGE TO THE COPPER MESH. IT IS REPORTED THE DAMAGED IS CAUSED BY THE CONTACT WITH LOOSE RIVETS ON THE WING TO BODY FAIRING. EMBRAER WAS CONTACTED AND ADVISED TO PERFORM TAP TESTS, REF /4/ SRM, AND REPAIR COPPERFOIL MESH OR BONDING PLATE, IF APPLICABLE; EMBRAER APPROVED THIS REPAIR PER REF /2/ ETD AND IS CLASSIFIED AS MAJOR.