COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES Piper PA-34 (Seneca) Series Aeroplanes AD/PA-34/6 Amdt 2 Exhaust System - Inspection 9/73 Applicability: Model PA34-200 S/Nos. 34-E4, 34-7250001 and higher, fitted with exhaust stack assemblies P/N 96465-00 and 96466-00. Requirement: PART 1 Inspect the exhaust system for cracks or broken pipes in the vicinity of all welded areas and feel for any looseness of the pipes in the vicinity of mounting flanges. Note: The above inspection may be performed and certified by the pilot. PART 2 Carry out inspection in accordance with Piper SB No. 373A or FAA AD 73-14-12. In addition remove the cabin air heater shroud and inspect the exhaust pipe for chafing marks made by the shroud. Also inspect cowls for chafing marks. Compliance: Part 1 - At each daily inspection. Part 2 - Within 10 hours time in service after 28 September 1973 and thereafter at intervals not exceeding 25 hours time in service.