Aside: Many years ago I had an idea for something, which may or may not be plausible, and even bought a couple of books on invention and patenting, so I could perhaps develop it. I never did. Not my realm. BUT. My thought was:

Could you have inflateable control surfaces on lowish-speed wings and aerodynamic surfaces, such that instead of bending and extending using hard surfaces, areas could instead be inflated or deflated to change the dynamic of the overall lifting surface? frontal edges, top and bottom, some trailing surfaces. Wings could become thicker or thinner, at different points.

Only seems to make sense on slower, prop-driven haulages, such as here.