propeller pitch

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thing73
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propeller pitch

Post by thing73 »

I have a macauley prop 71/48 and know this is considered a cruise prop.... I know a climb prop would be less than 48... what is a reasonably pitch for a climb prop???
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6183
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Re: propeller pitch

Post by 6183 »

https://mccauley.txtav.com/?PropType=fi ... 2F%20(TCM)
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6643
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Re: propeller pitch

Post by 6643 »

thing73 wrote: ↑Mon Oct 25, 2021 7:52 am I have a macauley prop 71/48 and know this is considered a cruise prop....
7148 is considered a "normal" prop for the C85. 7146 would be a climb prop. To optimize climb, find the pitch that gives you the maximum allowed static RPM.
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6643
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Re: propeller pitch

Post by 6643 »

Interesting... It looks like Textron has reinstated the "Avoid continuous operation between 1950 and 2170 rpm" limitation!
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6339
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Re: propeller pitch

Post by 6339 »

6643 wrote: ↑Mon Oct 25, 2021 10:25 am
Interesting... It looks like Textron has reinstated the "Avoid continuous operation between 1950 and 2170 rpm" limitation!
If you select the C-90 engine it doesn’t have the restriction.
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6643
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Re: propeller pitch

Post by 6643 »

6339 wrote: ↑Tue Oct 26, 2021 9:03 am If you select the C-90 engine it doesn’t have the restriction.
It never did. McCauley rescinded the restriction in a service bulletin in 1949. I think Textron has just republished obsolete information.
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Re: propeller pitch

Post by cdoughty »

I asked McC this question and the response was "where did you see this??. The TCDS has no restriction and there is no restriction". I responded "heard it on your website" and haven't gotten a response yet. So John is right, unless you want to trust the web-master over tech support.
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Re: propeller pitch

Post by 6643 »

McCauley Service Bulletin 13
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Re: propeller pitch

Post by 8342 »

Thank you John for posting a definitive answer to the placard question.

Rick
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