Adjusting the Rudder

Actually my last post should have already been devoted to the topic "adjustment of the rudder". So right now, it's about time to keep my promise.

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1) Elevator

Turn the trigger down --> rudder moves upward --> plane moves up

Bild: rc-modellflugzeug.de

Caution! This rule is only valid, as long as the elevator is positioned behind the center of gravity. One of my planes has its elevator in the front part of the plane, before the CG. This means for the plane to move up, the rudder has to move DOWN.

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2) Aileron

Turn the trigger right --> right aileron moves up/left aileron moves down --> plane turns right

Bild: rc-modellflugzeug.de

In this case, there is no exception to the rule. The aileron always works this way.

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3) Exponential

There's no common rule of how to use exponential, in this case I can only share my own experiences. In case you have different experiences, feel free to comment them. At the time, I am using a 50% exponential.

What does it mean?
The sensitivity of the transmitter output is adjustable, not linear to your trigger movement.

• when you turn your trigger rigth for the first 50% of the total scope, it turns smoother and slower 
• for the second 50%, the rudder moves exponentially faster and stronger

What's the consequence?

All in all, it's by far easier to handle all kinds of planes. Aggressive ones can be handled smoothly as long as you keep moving them within the first 50%. Great moves are also possible with slower planes, when you make use of the positive exponential.

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4) Delta Mixer

Some real military jets make use of the delta mixer. 

What does it mean?

The elevators don't move in parallel, but opposite to each other.

What's the consequence?
The rudders aren't only used as elevators, they are also used as ailerons.

To share my experiences so far: In my case, the elevator was quite strong, but the aileron was way too lame. I had to use the front wings as an aileron additionally to gain enough movement.

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5) Adjustment: Torsial moment of the props
If you have planes with only one prop, you have to consider its torsial moment. The torsial moment of the prop causes a slight counterrotation of the plane. Exaggeratedly this would mean that the plane would continuously rotate around its own axis. To encounter this, i usually trim the aileron in a way that it balances this rotation.

The bigger the prop, the stronger the rotation will be.