Pitch differences - with 3 or 4 blades

[cloumar]

The difference between pitch sizes - is it the same range for a 3 blades and a 4 blades.

I mean knowing that it is a +- 200-rpm per inch on a 3 blades, is it the same range for two different pitch 4 blades prop ?


Thanks

MC

 

[walleyehed]

Re: Pitch differences - with 3 or 4 blades

Yes....and No.
Yes a 24P (stamped) would drop somewhere in the ball-park of 150-200 vs. a 22P of the exact make and model.
To be honest, with so many designs available today the 200rpm deal is pretty general. I think the best way to put it with the newer designs is to expect a rise when dropping pitch and likely a drop in rpm when going up ...I know that sounds stupid but I have been fooled myself with some of my prop tests. it also depends greatly on where you are rpm-wise to start with. If your running on the lower half of the rpm range, expect more drastic figures.
But yes, the same rpm "general rule" applies the same 3, or 4bld.

 

[cloumar]

Re: Pitch differences - with 3 or 4 blades

Thanks for the reply Walleyehed !