RCU Forums - View Single Post - Three bladed props vs. two bladed props.
Old 11-23-2010 | 09:48 PM
  #25  
skillet92
 
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From: camden, SC
Default RE: Three bladed props vs. two bladed props.


ORIGINAL: Sport_Pilot


ORIGINAL: eddieC

For our models, there's little difference.

From a design & efficiency standpoint, the fewer the blades, the better. The primary reasons for number & diameter of props on full-scale is prop clearance and keeping prop tip speed below the speed of sound (big loss of efficiency).
Then why does a large plane like a C-130 with absolutely no ground clearance problem go from a four blade prop to a 6 blade prop? Reason because the 6 blade prop has lower tip speeds, is more efficient (see lower tip speeds), bites thin air better, and has higher high speed thrust.
Yes but the C-130 has Variable props and can do any pitch it wants to! I have seen them turn like a tank. I promise it is a cool sight!

Comparing a Turbo fan to our RC Motors is not practical because the blades on most full scale aircraft stay the same RPM they just change pitch.