As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DD5 (AFT) INTERCOSTAL P/N 601R31902-317 HAS CORROSION ON UNDERSIDE OF INNER SKIN ATTACH FLANGE AND VERTICAL LEG (MARKED) (C-CHECK RO 6/22/2021) NO SRM ALLOWABLE LIMITS GIVEN, REMOVED AND REPLACED WITH NEW DD5 INTERCOSTAL REF. CRJ-900 SRM, 51-42-06-001-001-A01 AND DWG 601R31702 REV-N. COMPLIED WITH TASK CARD 51-900-1002-SKY, PRESSURE CHECKS GOOD.