As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PDX - LEFT HAND WING CUTOUT FLANGE FOR ACCESS PANEL 524BT HAS FRETTING DAMAGE AT BOTH ENDS OF MATING SURFACE. BLENDED OUT FRETTING CORROSION. DAMAGE FOUND TO BE BEYOND LIMITS. MAPPED AND SENT TO ENGINEERING. REPAIRED IAW HORIZON AIR EA 6-57-232 AND RD 8/4 57-352.