Hi,
I came across a PDF doc on the [link=http://www.masterairscrew.com]Master Airscrew website[/link] and thought it does a good job explaining some prop basics. This is good, slightly more technical info for beginners to make more sense of the elusive question of "Which prop to use?".

http://00e2fac.netsolstores.com/imag...ler%20info.pdf

There are a few other PDF's on the site also... like one which contains the usual generalized prop size tables. That document also contains a formula for estimating max rpm when using nylon props which I thought is probably a very useful starting point... the formula:

RPM Operating Limit (for nylon props) = 165,000 divided by Diameter in Inches

Just thought I'd throw that out there. I thought it was a good find and clarified some things for me.

Cheers

just as a heads up

For apc max rpm = 190 000/ prop Dia. (inches)

Steven

Do you mean that max RPM for a 10 inch APC is only 19 RPM? Doesn't seem worth the trouble of starting the engine does it? Why do I think you mean 190,000/Dia (inches).

At least one of us was paying attention

Thanx for catching that one I fixed the post

Steven