Airworthiness Directives; Cessna Aircraft Company Model 182S Airplanes

This amendment supersedes Airworthiness Directive (AD) 98-13- 10, which currently requires repetitively inspecting all engine exhaust muffler end plates (four total) for cracks on all Cessna Aircraft Company (Cessna) Model 182S airplanes, and replacing any muffler where an end plate is found cracked. AD 98-13-10 also requires fabricating and installing a placard that specifies immediate inspection of all engine exhaust muffler end plates any time the engine backfires upon start-up. This AD is the result of Cessna developing an improved design exhaust system for the Model 182S airplanes. This AD retains the actions of AD 98-13-10 on all affected airplanes, and requires replacing the exhaust system with an improved design exhaust system within a certain period of time, as terminating action for those requirements retained from AD 98-13-10. This AD also limits the effectivity to exclude those airplanes manufactured with the improved design exhaust system. The actions specified by this AD are intended to detect and correct damage to the engine exhaust mufflers caused by cracking and the high stresses imposed on the attachment of the exhaust system at the area the firewall, which could result in exhaust gases entering the airplane cabin with consequent crew and passenger injury.