Question: I’m in the process of training someone on the buddy box. I have a scratch-built trainer that has a AR 6210 Receiver. After flying a couple of times, it appears that the plane is not so stable. However, I do have a AR636B 6 Channel AS3x Receiver. Would this be a better receiver for the student than the AR 6210?

Is the trainer unstable for you or just the student? Even though it might take a little longer to solo, I would suggest that the student is better off learning to fly the plane rather than depending on the stability assist. You might be able to make the trainer more stable by moving the balance point a little farther forward, just 2 or 3% of the total wing chord.

Mrcoolpop,

The answer given by aeronautical engineers to all such stability questions is: "It depends." Sorry, but your description does not contain enough information for me to provide a definitive answer. It would be helpful to know which model you scratch built (glider, sport, slab-foamy bi-plane etc.). Is it your own design, or did you build it from plans? Was the model built straight? Describe how the model is unstable, i.e. is it pitch sensitive? Is it roll divergent? Is it sensitive to power changes? Does it try to stall and/or snap roll when up elevator is applied? Do experienced pilots also consider it to be unstable? Is it overweight? Is it underpowered? Is the wing swept or tapered? At what percentage of the wing cord is the center of gravity (including interpolation for wing sweep or taper)? Will it fly straight and level "hands off" in calm air for at least 10 seconds. How much dihedral does the wing have? Are the control rate switches on the buddy box set to provide the same or less control surface movement than those on the master transmitter?

AS3X is primarily intended to instantly help the model recover from rapid pitch/roll/yaw changes such as are generally caused by turbulence. The AS3X response is much quicker than human reflexes and makes the model feel more stable in turbulence. If the model is mildly unstable, then the AS3X probably won't help all that much. The full SAFE mode for beginners, which has preset "auto-pilot" limits for pitch and bank, might help some. The only way to know for sure is to swap the receivers and try it. Of course, you would also need to program the AR636B receiver to match your model.

Sorry I'm not much help on this one.