New brushless setup not smooth
 

I just got an original walkera brushless motor and speed control for my dragonfly 36. It is WAY more powerful than the stock motor, but the problem is that when I advance the throttle, no matter how slow, it spins around some when getting ready to take off cause it throttles up so fast (It does this very fast, there is NO way to fight it with rudder). Once I get past that point, it is ok, and then I can fly it. In the air I also noticed another point at which it really took off when I gave it just a little throttle. I never noticed this with the brushed setup, but it was hardly powerful enough to get the heli more than a couple feet from the ground. The helicopter is a stock Walkera dragonfly 36 w/ walkera radio. Thanks for any help you can give.

RE: New brushless setup not smooth
 

The spinning during spool up is a problem among various helicopters. Not all are affected by it, or affected as badly as others. It's because the tail isn't spinning fast enough to counter the torque of the main blades during spool up. The only real solution I know of is trying larger tail blades. This will increase overall tail power, but load the motor a bit more during flight. And, of course, theres no guarentee that will fix anything, it may just make the problem not as pronounced as it was before.

I find this problem is more common among micro helis than it is among larger ones. Most micros i've had exhibit the spin on spool up to some degree, yet my eco-8 is rock solid throughout it's throttle range.


As for your second problem, dunno, never used Walkera ESC's, no idea what their throttle resolution stepping is like.

RE: New brushless setup not smooth
 

Try to spool up by using your transmitter's trim. With the throttle stick all the way down move the trim up until it starts spinning..

RE: New brushless setup not smooth
 

also, fly off of grass or something with a little bite in it...flying off od a smooth surface like concrete will make the problem worse because the skids wont have anything to hold onto..

RE: New brushless setup not smooth
 

Thanks for the tips. I have been taking off on concrete because it's the only spot I have to take off from. I will try using the trim. So I'm taking it that this is normal with the brushless setup alot of times (wasn't sure if that was just some of that great Walkera quality :). I've flown a dragonfly 4, a colco cyclone, and this dragonfly 36 with brushed motors and none of them took off like that, I could spool up slowly if I went very slow on the throttle. I haven't had much time to mess with it yet, but I haven't been able to take the training gear off because the way it does that. I already like this heli though, as seeing it can handle more than 10 times the wind my #4 could, which means I can fly on an average day.

RE: New brushless setup not smooth
 

It won't affect motor driven helis as much becuase the tail speed is controlled seperately by an independant motor. On a driven tail helicopter, the tail can only go as fast as the main driving motor allows it to. Hence, during spool up, if the tail isn't spinning quick enough, no ammount of pitch will counter the main torque being placed on the helicopter by the main blades untill the overall headspeed (and tail speed) picks up enough to generate the required thrust.