Service difficulty report · Muffler · Robsin R44RAVENII

Difficulty date
September 13, 2010
Submitted
January 4, 2011
Operation
General aviation
Make and model
Robsin R44RAVENII
Aircraft time
479 hours
Engine
Lyc IO540AE1A5
Part
Muffler
Part number
C16932
Condition
Melted
Location
Engine
Part time
540 hours
Stage of operation
IN
How discovered
9
Nature of condition
B
Precautionary procedure
K

As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.

What was found

EXHAUST MUFFLER C169-32(C169-31 SUB ASSEMBLY) SENT IN FROM CUSTOMER AT 540.0 TTSN. MUFFLER HAS MASSIVE FAILURE AT THE TAILPIPE ATTACHMENT JOINT. OPERATOR IS AWARE THAT THESE FAIL. THERE IS NO AD ON THESE AND THERE REALLY SHOULD BE. AD CF-90-03R2 DOES NOT COME UP WHEN IN CAWIS. PRIOR TO OBTAINING PDA09-02, 98 INSTANCES WERE RECORDED BY US WITH IDENTICAL FAILURES. UNIT WILL BE REPLACED WITH C169-32AWL WHICH USES A HIGHER HEAT CAPACITY MATERIAL IN THIS AREA. A TOTAL OF 78 PDA UNITS ARE IN SERVICE WITH MANY HAVING 800+ HOURS WITHOUT SHOWING THIS DEFECT. THERE SHOULD BE A AD SPECIFICALLY ON C169-3 AND C169-32 UNITS. C169-3AWL AND C169-32AWL SHOULD BE INCLUDED BUT SHOULD HAVE A HIGHER INITIAL COMPLIANCE TIME.