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I read a post on one of the heli forums that said they use no dual rates or expo. I wonder if they like that or someone told them that’s the way the Pro’s do it.

I use both and here’s why. The throws on a rotary servo are NOT linear. The pushrod connected to the servo arm travels much more when the servo moves near center than it does at extreme throws. My understanding is that it takes about 20% soft center expo (negative expo for Futaba) to make the pushrod throw linear. I use about 30% to give me mostly linear feel but a little softer center.

I set my control throws mechanically for what the flight control system says it needs. It may be 9 degrees of cyclic or 12 degrees cyclic, depending on what gyro you are using That is how much control the “gyro” has available to make corrections. For me, that is WAY too much control. I use the dual rates to cut down the control throw (not gyro correction) to get the feel I want in cyclic and the rudder. For me, that is low rate. I then pump up the high rates 10-12% just in case I get a really gusty windy day that requires more authority. My hover rates are really low. Back in the day, it was 30-35% aileron and elevator. Now with the rates being set in the gyro, my transmitter rates are about 80% in low rate and whatever I need in high rate. I do change the rates in the gyro rather than the transmitter EXCEPT if I need to make a quick change during a contest or demo flight. Then I can use the transmitter. Now that my transmitter talks to the gyro, I rarely ever have to do that as I can change the gyro as fast as I can change the transmitter.

I set my rates in aerobatics to get the smoothness I want and the control authority I need, and they are different than hover as is my gyro rate. Ask any contest pilot (or pro 3D pilot) and they will tell you they spend a lot of time getting things adjusted to get a certain feel. Not everyone likes the same thing. I have hovered Cliff Hiatt’s contest model and his is softer than mine as his reflexes are better and he never lets it get away from him. I’m a little slower so need a bit more to “catch” it when I’m behind.

Geena’s model is much quicker than mine as she flies a lot of 3D and is used to that feel. It’s all about what you need to make it feel like YOU want. The more you practice, the more defined the feel you want becomes. Think about it.

~ Gordie Meade, ARCCHS Facebook