[WWI] DML Wings Fokker Dr.1 and Spad XIII

[Diego Fernetti]

Hi Art!
>  The saggy undersides seem impossible to fix. Are there any replacements 
> for them?
> Same for the DML Spad XIII?

Perhaps they're a bit exaggerated (I can't recall that kit too well) but 
take into account that undercambered wing profiles caused the fabric 
covering to "balloon" in between ribs, because the taut fabric tends to 
follow flat surfaces. The same effect, but reversed, can be seen in the top 
of the wings (a convex surface) by the slight dip at the apex of the rib 
curves. In any case, this effect diminish at the leading and trailing edges 
of the wings, being the rib profiles less curved. And as you may have seen, 
many airplanes had riblets to minimize the airfoil distortion in between the 
ribs.
As a remedy for the deep trenches in the wings undersides, I'd carefully 
sand the undersides, especially in the trailing edge areas. Rescribe the rib 
tapes with a slight pass of a hobby knife.
D.