What was found
RT MUFFLER/EXHAUST LITERALLY FELL APART IN FLIGHT. BEYOND REPAIR. THE INLET FLANGE/PIPE ASSEMBLY COMPLETELY BROKE LOOSE FROM THE MUFFLER BODY. THE EXHAUST HANGAR, A RUBBER STRAP, WAS THE ONLY PART SECURING THE MUFFLER BODY TO THE AIRFRAME. THIS PART WAS PREVIOUSLY REPLACED APPROXIMATELY 500 HOUR PREVIOUSLY. THIS IS A CHRONIC PROBLEM WITH THESE MAKES AND MODELS AIRCRAFT. REPLACEMENT PARTS ARE NOT READILY AVAILABLE. AIRCRAFT WAS AOG FOR THREE WEEKS.