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Old 04-10-2008 | 02:25 PM
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opjose
 
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From: Poolesville, MD
Default RE: 3 blades - easier?


ORIGINAL: flyX

More blades to spin will require more power to trun the darn thing of course.
Not quite...

Typically when going to 3 blades you step DOWN diameter or pitch to produce the equivalent demand on the motor.

e.g. instead of using an 11x6 2 blade prop, you can get the same power output and performance by going to a 10x6 3 blade prop.


ORIGINAL: flyX

Anyway, there's a thing call a threashold...Just becuase your engine spin at a higher and higher rmp dosn't necessary mean
it'll produce more HP. At max rpm your engine will actaully produce less HP.

Example if your engine Max RPM is 16000. It's max HP output threashold might be at 13500 rpm.
Which is why when moving to 3 bladed props we adjust for the difference.

However if you apply the proper rule of thumb, there is no net difference between 2 and 3 bladed props....

At the least for this "beginners" discussion.