FAA AD 2018-02-04
Aerospace Welding Minneapolis, Inc. applicable on Muffle installed on Cessna 172R/S. Effective Date of this AD is February 21, 2018 Muffler part No. A1754001-23 172R S/Ns 80001 and up; 172S S/Ns 8001 and up. Muffler part No. A1754001-25 172R S/Ns 80001 and up; 172S S/Ns 8001 and up; This AD was prompted by occurrences of cracks or broken welds in the connecting weld of the muffler body to muffler cuff that may allow carbon monoxide (CO) exhaust fumes into the cockpit heating system. We are issuing this AD to prevent cracks in the connecting weld of the muffler body to muffler cuff that may allow CO fumes to enter the cockpit heating system and possibly inhibit the pilot's ability to maintain control of the airplane. Compliance : Comply with this AD within the compliance times specified, unless already done. Inspection of the Muffler (1) Within 5 hours time-in-service after Febru...