As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
YYC: CENTER WING UPPER ACCESS HOLE REBATES FROM STA RT YW42.00 TO LT YW42.00 HAVE FRETTING CORROSION AROUND BOLT HOLES AND SCRATCHES ON THE UPPER SURFACE. MAINTENANCE REPAIRED IAW Q400 SRM 51-21-00-350-801, SRM 51-21-10-380-801 AND SRM 51-25-10-370-801.