I have two questions for the OP:

1. What were the wind conditions like when you were flying?

2. Was the problem constant throughout the flight, or was it sporadic?

I had one of these planes for a while, and I can say that it was a little goofy. One guy in my club let me fly his, and he did not like it at all. It would kind of bobble in the pitch axis. He had a huge engine in his, like a .90 2 stroke. SO he had some barbell effect going on with his weight and CG. A lot of weight up front, and in the back to counter it.

Mine flew really good actually with a Saito .56. I could lock that thing into knife edge and fly it around the sky that way. It was a really fun plane. I do seem to remember that you had to fly it all of the time. Not sure it is worth spending a lot of time getting this design rock solid stable. It may not be capable. If you servos good, your linkage is tight, then it should stay trimmed. If not, something is probably moving. Like you need to tighten the wing bolts more. Or wrap tape on the anti rotation pins to tighten them up.

I was under the impression this airplane has a one peice wing.

No, it is like a big one. Wing tubes, bolts through fuse side, anti rotation pins if I remember at the LE and TE. It is pretty small too, so it could be a little squirrely at times, especially on higher rates. That is what I thought made it fun.

For my two cents on the AILE issue. You can have great servos and great linkage and have weak extensions or Y harness. Turn it all on and try to deflect the AILEs with your hand. I bad lead can drastically reduce the strength of the servo. If your issue is not there. Get out the incidence meter.

David

you are correct, I was thinking it was the older version. I'm still leaning towards the servos not centering.

Or the wing panels moving on the anti rotation pins. How old is this plane?