I’m currently trying to figure out what the optimal rotor configuration would be. Is the primary reason the builds tend to be quad-prop to take advantage of using 4 smaller electric motors? Has anyone considered using a planetary drive, and considered the weight/efficiency implications of using a planetary drive to allow say, four motors to power 2 props?
My goal is for the most efficient (of course), and quietest prop arrangement I can come up with while mitigating torque effect (Which I’d imagine could be particularly nasty from an electric motor if thrust isn’t attenuated). From what I’m reading, multiple smaller props don’t hit either of these criteria, though an even number of props resolves torque effect.
Two large contra-rotating props would be more efficient I believe, but are apparently fairly loud. (I’m not sure if they’re more or less loud than 4 smaller props)
I was considering one large prop, and one medium sized prop… I believe this would largely reduce the sound of the second prop from my perspective while offering some mitigation of torque effect. I expect this would have a notable efficiency draw-back unless the second prop was mounted somewhere with it’s own air supply.
Any thoughts? What have others concluded from researching prop size / number?