As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
THIS AIRCRAFT HAD THE NR 1,NR 3,NR 5 HEADERS REPLACED WITH NEW PARTS AT 154.0 HRS. THE AIRCRAFT THEN EXPERIENCED A CRACK IN THE NR 5 HEADER AT 180.0 HRS. THERE DOES NOT SEEM TO BE ANY ABNORMAL STRESS ON THE PART/INSTALLATION. AIRCRAFT EXHAUST SYSTEM WILL BE MONITORED TO INSURE INTEGRITY.