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Old 06-26-2012, 06:10 PM
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Crumpp Crumpp is offline
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although 3.3m prop share same slope curve as 4m prop outside the envelope, the 3-meters prop working point is on the right side of 4-meter due to higher advance ratio, which means less efficiency.
Not sure what you are trying to say here...

You do understand you cannot compare propellers at different advance ratio's???
It is not in any way or form valid.

I think this where you are getting confused.

Advance ratio is analogous to angle of attack.

If you looked at angle of attack in isolation as a measure of turn performance for example, you would erroneously conclude that the aircraft at the higher angle of attack can outturn one at a lower angle of attack.

This is patently false and has no bearing on turn performance.

You can only make a valid comparison of propellers at the same advance ratio. The fact other propellers can achieve higher advance ratio's has no bearing on their performance when compared to lower advance ratio propellers anymore so that wing angle of attack can be used for turn performance prediction.
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