As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING IMBV INSPECTION, QA FOUND CORROSION ON THE CENTER HAT BEAM AT FR 20. AIRCRAFT WAS REMOVED FROM SERVICE FOR IMBV INSPECTION AND WILL BE RETURNED TO SERVICE AFTER IMBV INSPECTION. REMOVED AND REPLACED CENTER HAT BEAM BETWEEN FR16 AND FR23 IAW SRM 51-40-02 AND 51-40-03. AIRCRAFT WILL BE RETURNED TO SERVICE AFTER IMBV INSPECTION. (REPAIR PART 145-21713-605)