One of the options I'm considering for my outer wings is to make them without spars using a sandwich for both the upper and lower skins. I'd also like the outer wings removable for trailering but the conventional way of doing this is to use spar stubs that slid or bolt into place. This means gathering up all of the loads from the skins and transferring them to the attachment point. This adds weight and complexity. Below is a sketch of an idea I have to avoid this and use a distributed attachment that can be sandwiched between the skins with just local reinforcement - similar to the way the wing attach fittings are bonded into the EZ center section. The little blue thing is rotated to release the wing. Quick calculations indicate that friction of aluminum to aluminum would be enough to keep the joint together without having to positively lock it together. The slots are to allow the fitting to be milled flat and then follow the curve of the airfoil. Has anyone ever tried something similar? Edit: change aluminum to steel on steel.