McCauley prop question. 'CF' vs. 'CM' differences

[fearofpavement]

Re: McCauley prop question. 'CF' vs. 'CM' differences

Ok, did some research, found a lot of data on this situation and the result is that I am more confused by what i found than I was before. So I am fading into the background on this one...

[n6346m]

Re: McCauley prop question. 'CF' vs. 'CM' differences

I guess we'll probably never agree on this, but if the manufacturer states that the TSIO-520M is a direct replacement or interchangeable for the TSIO-520C then that's good enough for me. If an unknowledgeable FAA type refuses to give you a field approval and the old engine is no longer available, I really doubt that the only alternative its to scrap the airplane.

[fearofpavement]

Re: McCauley prop question. 'CF' vs. 'CM' differences

I guess we'll probably never agree on this, but if the manufacturer states that the TSIO-520M is a direct replacement or interchangeable for the TSIO-520C then that's good enough for me. If an unknowledgeable FAA type refuses to give you a field approval and the old engine is no longer available, I really doubt that the only alternative its to scrap the airplane.

I mentioned this engine because we made that exact change on a Cessna TP206A. But is was via an STC from RAM Aircraft.

I did research the propeller issue and confirmed two things: 1 is that McCauley does consider the 1A90 and the 1B90 to be interchangeable. 2 is that the FAA issued type certificate data sheet is "approved data" and that is where it states that the two props are interchangeable.

I think if I were going to install a 1B90, I would fill out a 337 referencing the TCDS from McCauley. I am not completely convinced at this point that the 337 is even necessary but would do it "just in case". I am convinced that either prop can be used on the T-craft.

Now regarding the tire ply rating....

[Mark Julicher]

Re: McCauley prop question. 'CF' vs. 'CM' differences

Read note number 10 on the TCDS.