Wing mounting, Part 1. The most serious flaw in the Vertigo II is the wing saddle. There is roughly 2 degrees of negative incidence in the wing saddle, depending upon where you position the wing fore and aft. The wing is actually too narrow of a chord. The chord at the root is what it should be if it were at the fuselage side. The chord should be longer as you project it toward the actual centerline. Consequently there is a gap at the leading edge when you move the trailing edge back to the rear of the saddle, which is the correct position.

Fortunately, I figured this out 33 years ago. Wing cores that I cut for this airplane in the future will have the correct root chord, and the fuselages will have a correct saddle. But that is for another day.

Here is my solution for this particular aircraft. I cut a bulkhead from 1/4" ply, and capped it with 1/4" balsa to save some weight. I want to key this into the old brittle fuselage really well to add some torsional rigidity to this section. The wing bolts will anchor the other end of course. I used three dowels rather than the regular two for a bit of overkill. The middle one is not really necessary, but it looks cool, and makes me feel good. I will back this up with a gusset, and some glass strips to the leading edge.

The wing is shimmed to the correct incidence, thanks to my trusty Robart incidence meter. The wing is aligned correctly, and the leading edge is epoxied to the front mount. I epoxied 1/16 ply wing screw plate to the trailing edge. The wing hold down piece the mounts in the wing saddle is cut from 1/4" ply. I tap the 1/4-20 threads right into the plywood. To save weight, I put the piece in the Bridgeport, and mill a slot to take out some unnecessary material to save some weight. This piece is epoxied in place with 5 minute epoxy. The wing saddle flanges are much stiffer now from the added layer of glass applied to the inside of the fuselage from the previous step. This wing won't be falling off anytime soon.

If I laid everything out correctly, the bolt holes will come out right on or really close to the marks on the bolt plate (wing saddle). We will see in the next post. Stay tuned.