Was tried wwwaaayyy before that Bill, in the 30s (maybe even before!)
And for Planes, I believe in the 20s
I think at the time, everything has been tried. That's without talking about the wing warping ones.
In relatively more recent years, you have something like the HKS-1 glider. No ailerons, flexible wing
That one is from the 50s if I remember.
And a few more that went from expendable wings, to variable in flight dihedral etc that the Germans, and others, tried in the 30s