Cees,

You've got it backwards. Look at any good set of plans that shows incidence, you'll see negative is leading edge down.

The reason for the +.3 wing and -.3 on the stab is simple. A truly symmetrical wing will not fly at 0 degrees. It has to have a positive angle of attack before it will create lift. If you set a plane up 0 - 0 you will have to use up elevator trim to creat the positive angle of attack.


Bob