As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING HEAVY MAINTENANCE CORROSION WAS FOUND ON BEAM (P/N 170-66280-001) AT S-28R BETWEEN FRAME 80 (X = 21192) AND FRAME 81 (X = 21617). THE CORROSION WAS BLENDED OUT RESULTING IN TWO BLEND OUTS. THE FIRST BLEND OUT IS 2.9" L X 1.0" W, X .05" D AND THE SECOND BLEND OUT IS .9" L X .35" W X .11" D WHICH IS OUT OF LIMITS. THE CORRODED BEAM WAS REMOVED AND REPLACED WITH A NEW BEAM PER EO E175-53MR-417.