Hi Vlad,

Re your incidence angles. IMHO a positive (Leading Edge Up) stabilizer incidence angle on a model DVII is not what you want. That's because cambered airfoils have a nose down pitching moment in addition to their Lift and Drag. For the airplane to be in equilibrium the nose down pitching moment of the airfoil must be balanced by a nose up moment generated by a down force at the horizontal tail acting on the long lever arm to the CG.

I would think the stabilizer incidence should be 0 deg, parallel to the fuselage Centerline. In the air in level flight the wing, because of the strong lift generated by the DVII's thick cambered airfoil, will probably trim out at -1 to -3 degrees. This effectively puts the stabilizer at a negative angle of attack, generating the down force needed.

Hope this is of some help. Your DVII sounds like a great project. Good luck with it.

Tom