COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES Cessna 180, 182 and Wren 460 Series Aeroplanes AD/CESSNA 180/77 Aeroquip Engine Exhaust Mufflers 7/98 DM Applicability: Cessna 182S model aircraft incorporating Aeroquip engine exhaust mufflers part number (P/N) 71379-1254017-8. Requirement: Replace the Aeroquip mufflers in accordance with Cessna Special Service Project SSP98-78-03. Note: FAA Airworthiness Directive 98-01-14 refers. Compliance: Effective 6 May 1998; before further flight. This airworthiness directive becomes effective on 6 May 1998. Background: This directive has been issued to require the removal from service of certain part number Aeroquip engine exhaust mufflers to prevent carbon monoxide contamination of the cabin heating system or the aircraft cabin. The requirement follows advice of certain mufflers produced by Aeroquip may have inadequate or failed welded joints.