Prop pitching

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Massimo
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Prop pitching

Postby Massimo » Tue Jul 07, 2009 9:19 am

Ok someone please clarify this for me:

I was under the impression that a coarse prop will give you more climb but less speed and a finer pitched prop will give you more speed but less climb, or is it the other way around? If i want to increase my revs that will mean making the prop less coarse therefore reducing the climb but increasing the cruise, correct?
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Re: Prop pitching

Postby kloot piloot » Tue Jul 07, 2009 9:41 am

Quite correct. vhpy
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Sukkelaar
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Re: Prop pitching

Postby Sukkelaar » Tue Jul 07, 2009 9:54 am

I ussually think of a nut on a screw thread. On a coarse thread a nut will move advance 3mm if turned one revolution,and 1mm on a fine threaded screw.
Therefor a coarse prop will be faster.

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Mogas
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Re: Prop pitching

Postby Mogas » Tue Jul 07, 2009 10:28 am

Sukkelaar has it right.
Fine pitch = higher RPM and better climb performance.
Course pitch = lower RPM and better cruise performance.
Think of it as lower gearing for hills and higher gearing for speed.
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Re: Prop pitching

Postby kloot piloot » Tue Jul 07, 2009 1:34 pm

Oops ! :oops: I read like my @rse !

What I meant was
If i want to increase my revs that will mean making the prop less coarse
is correct.

Thanks Mogas and Sukkelaar for the correct info.
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Duck Rogers
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Re: Prop pitching

Postby Duck Rogers » Tue Jul 07, 2009 2:42 pm

Nice analogy Sukkelaar vhpy
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