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Old 08-12-2016, 10:03 AM
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n233w
 
Join Date: Apr 2010
Location: Richmond, CA
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My sense is the answer to your question is undefined. An aeronautical engineer might be able to give you a theoritical figure but...

Pattern pilots use the ESC brake function for slowing the aircraft.

Originally Posted by JerMilosek
I've read that a prop spinning at a low rpm creates more drag than one that's free wheeling.


My question is at what rpm is the greatest drag created?


This comes about because I want to slow down the aircraft more and sooner during a landing.
E-power has the luxury to preset the "idle" rpm anywhere from 0 to 2000 rpm, where in that
range will I get the greatest drag/thrust ratio? I haven't gotten into fixed end points and braking
yet but looking at the logged data from my Castle ESC, I can see a long spool down. Its in the
10-12 second range from the time I hit low throttle until the rpm as reported by the ESC bottoms
out at around 450 rpm. Its under no wind, a long gentle glide with the rpm around 2100 when
low throttle is applied and its using an outrunner.

Thanks, J e r

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