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Old 02 November 2007, 18:00   #1
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Diameter of propeller Question?

What effect has using different diameters of propeller on your RIB?

I figured that a 21" Pitched 14.750" dia prop would be harder to drive that a 13.75 dia prop of the same pitch? What would happen to slip etc? Would it be better to go for a 19" stainless prop to gain the nessesary 500RPM needed for my installation?

Just having a think out loud for the moment as there are other factors to consider, like checking throttle position, making sure engines working correctly etc...
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Old 02 November 2007, 18:08   #2
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100 WOT rpm per quarter inch is what I have heard is generally used. Bigger turns slower.

jky
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Old 02 November 2007, 18:10   #3
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But (all other things being equal), gives you more grip,.

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Originally Posted by jyasaki View Post
100 WOT rpm per quarter inch is what I have heard is generally used. Bigger turns slower.

jky
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Old 07 November 2007, 13:28   #4
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Andy I have a 19" BRP Ali prop you are welcome to try out, it would at least give you an idea of performance.

Remind me what prop you are running at the moment?

Chris
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Old 07 November 2007, 16:24   #5
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Andy I have a 19" BRP Ali prop you are welcome to try out, it would at least give you an idea of performance.

Remind me what prop you are running at the moment?

Chris
That would be excellent in reverse
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Old 07 November 2007, 17:48   #6
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Yes it is counter rotating, that's very funny

I have seen a 19" Viper that hopfully I will be trying out on Friday.

Thanks for the thought Chris, shows your hearts in the right place
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