Read these three posts from the VP turtledeck options thread:
In your stability calculations, have you accounted for the downwash from the canopy impinging on the flat top of the aft fuselage boom? It will give you a pitch up moment you need to accommodate. A 'standard' stability analysis will miss this. Notice how the PIK has a turtledeck that runs all the way back to the tail. One of the things that does is reduce the pitching moment I just described. The wider the cockpit, the worse this pitching moment becomes.
Drag on the fixed landing gear also tends to add a pitch down effect with increasing speed, so I'll be interested to see if that canopy downwash has any noticeable effect in practice.
This is what your fighting except inverted.Yes, it does. I changed my plane from a flat-topped aft boom like the one shown to a traditional turtledeck because of the nose up pitching moment. I didn't see it in several stability hand calcs. I didn't see it until I ran viscous CFD.
This boom pitching moment was greater than the pitching moment from the landing gear drag.