Prop efficiency climbs (so I'm told) until it reaches speed of sound, so I believe some try to take the prop as close to 3,000 rpm as possible, yet some stay a conservative 2,700 rpm, what do you suggest, given all the variables.
George (down under)
Calculating the propeller tip speed just gets you close, because the airflow over the forward side of the blade reaches supersonic before the blade speed.
The spreadsheets for calculating all of this neat airplane stuff (by John Roncz) are available on the EAA web page.
If you have no spreadsheet, you can download one from Open Office.org
for free. Or the whole office suite. Works great. Compatible with everything, free.
You can fill in the dimensions of your plane and prop data and crank out the actual performance data within a percent or so. Scary accurate.
Lynn E. Hanover
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