RE: Need help for prop size on electric motor
So let's get a bit pessimistic, and assume that because you want a long flight time, the AUW of the plane will be 16oz.
Let's also shoot for over 140 watts / lb....
140 watts / 11.1 = 15A MAX current draw.
A 20A to 25A ESC will suffice, to save weight a 20A ESC would be good.
So we know that we want a 140 watt motor, a 20A ESC, and over 1lb of thrust...
This motor is just the ticket, when flown with a 10x4.7SF prop.
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