RE: Contra Rotating Propeller Drive for f3a 2m Pattern Planes
Hey Brian,
Yes, both props can move independently of the other. If you restrained one prop, the gear ratio for the remaining prop would be half what it is when both props spin free. It wouldn't spin twice as fast though because there wouldn't be enough power available from the motor to spin it that fast, but if you were able to rotate the pinion gear at the same speed, then the single prop would rotate twice as fast.
We could develop a Contra Drive that would work with an outrunner, but I don't think it would be practical for pattern because the resulting weight would very heavy. This is because outrunners don't have an existing gearbox that I can replace with my Contra Drive gearbox.
The best configuration is the Contra Drive coupled with an inrunner motor. Currently we plan to support the Hacker C50-14XL Competition motor, and the Neu f3a motor.