Here is an elevation showing the position and size of the semi-monocoque chassis. Attached to the monocoque will be the rear swingarm, and the front a subframe to locate pedals and front suspension pickups. Again using a semi-monocoque will hopefully make for a lighter velomobile. The semi-monocoque will have to be stiff enough to take loads from the subframes without excessive bending or twisting. I have decided that a good quality plywood would be best for the monocoque for cost for performance.