Righthand Leading Edge 2
The righthand center section leading edge in its “Dinosaur Bones” jig, looking inboard. The nose spar has been drilled off against the skin, and the ribs which sit between the nose spar and Spar #1 have also been positioned and drilled off against both the skin and nose spar. (Image via Pioneer Aero Ltd.)

Center Section Leading Edges:

Pioneer Aero’s engineering team has been working hard on the leading edges for the SBD’s wing center section for some time now. As noted previously, most of this structure suffered significant impact damage when the aircraft ditched in Lake Michigan during WWII. As a result, Pioneer has had to remanufacture nearly all of these components from scratch, a task which Hadon Smith has organized.

Righthand Leading Edge 1
Another view of the same assembly looking outboard, and following the primer painting of the inter-spar ribs. Note that the inter-spar ribs have yet to be drilled against the leading edge skin; that will happen once the ribs have been back-drilled against Spar #1 during the assembly final fitting. (Image via Pioneer Aero Ltd.)

Righthand Assembly Completed:

Smith’s team recently completed the principle structural elements for the righthand leading edge, from the nose spar forwards. They then back-drilled the forward set of inter-spar ribs and had them primer-painted, meaning that the righthand assembly is now ready for mounting onto Spar #1 (once that component is ready to receive it).

Another view, from the opposite direction, of the righthand leading edge assembly. Note that many of the key components are still clecoed together, and that the edges of the leading edge skins remain oversized. Final riveting (and skin trimming) will occur when the assembly can be offered against Spar #1. (Image via Pioneer Aero Ltd.)

Lefthand Leading Edge Beginnings:

With the righthand side essentially done, Hadon Smith began working on the lefthand center section leading edge assembly. He first reconfigured the "Dinosaur bones” - flipping the set of profile boards from righthand to lefthand use - and aligning the jig with a laser to ensure each board was positioned properly. Smith then started rolling a tapered radius into a sheet of appropriate gauge aluminum sheet to begin fashioning the new lefthand leading edge skin. Using an English Wheel, he fettled the skin's curvature until it fitted snugly into the jig. The skin remains oversized presently but, like the righthand unit, it will have its edges trimmed during final-fitting when the assembly is ready for mounting in the wing center section.

The set of lefthand leading edge ribs, formed at the same time as the righthand set, has undergone heat treating, straightening and trimming. Once the leading edge skin is correctly profiled, Hadon will fit, primer-paint and then rivet in these ribs to begin forming the assembly.

Hadon formed (and heat treated) the set of ribs for the lefthand center section leading edge at the same time he produced those for the righthand assembly. He recently trimmed trimmed these parts ready for positioning against the lefthand leading edge skin. (Image via Pioneer Aero Ltd.)