Which prop

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Hi guys I have seen most G200's have 2 blade props, and G202's have 3 blade MT. I am building a G202 which prop is better o use and why? Regards Michel Leusch Model.torque@gmail.com

Re: Which prop

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Hi Michel.

Ah, now you have moved from the realm of science into art/religion. :-)

Two-blade props are, of course, lighter than three-blade units. And, all things being equal, they are also more efficient.

However, three-blade props generate less vibration. And there is a potential resonance problem when combining a two-blade prop with high compression pistons and a non-counterweighted crankshaft. I suggest you call Martin Albrecht at MT Propeller in Germany to discuss this.

I prefer MT over Whirlwind because they have a better service history and require less maintenance. But Whirlwind has some wide-chord blade designs that offer better thrust at low speeds.

I use an MTV-15 two-blade prop with 198cm blades on my G-200 with an angle-valve engine and 10:1 pistons. David Noad of MT's service center in Florida said that he would recommend their 203cm (?) blades for a new installation, but that the performance difference wouldn't be worth the cost to upgrade.

Hope this helps.

Regards,
DJ

props

G'day Michael,

a late reply from me. I fly a Whirlwind 200C with IO-390, standard compression and electronic ignition, G-200. So far no problems and good performance. 3-blade hubs are heavier, but yes smoother. Depends a lot on your W&B situation.

good luck.

Grant

Evidence of Best Prop

I found this article years ago and the website is now down. Fortunately, I emailed myself the document and am posting it here for the group's benefit.

I think you will recognize the name of the author. They compare 5 propellers on the same aircraft with the same pilot and near same weather conditions.

Numbers are close but they speak for themselves:

https://docs.google.com/document/d/1URyL2PCZB0wGfmRjFnM0Iks8Va-zV1fc/edi...