I have had 2 Cubs and 1 had to much incidence or lift in the tail feathers, to solve the problem I added about 2 degrees to the front of the wing. The birds tail would lift to high and then the wing had to much down force and over it would go on its nose. the Cub I have now has about 2 degree up in the wing and the tail is level with the fuse I hope that helps you. Get one of those GP laser incidence meters and check them out you would be surprised what you find. I had a AT 6 that had 1 degree wash in on 1 wing tip and the other had 1/2 wash out on the the other.After finding this I called the Kyosho supplier and they replaced the wing, and the new wing is 1/2 wash out on both tips now and the plane flies great... It pays to check out those little things before you have big problems