Bill Freeman wrote:

       snip

Ken, we are going with the NASA 16 series for the variable pitch prop.

Paul Lamar

Paul,

I started with the 16 series, but eventually found that for our applications
we are better off with a somewhat smaller diameter, wider chord prop
with 24XX series due to much higher CLmax with this series than with
the 16 series.  You will have a much poorer off-design point performance
with the 16 series.   I suspect that for a certain class of designs, using
the 16 series for the outer few stations (3-6") would be worthwhile, but
for our first effort, I wanted to have a conservative design with a high
probablility of good performance.

Bill

Opps. Why are we worrying about off design points with a variable
pitch prop?  I can see that for a fixed pitch prop. 

Is this off the optimum twist design point?

BTW what is the "cord factor"?

Paul Lamar
 
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