Sorry if this is a topic that has been talked about before, but in a brief search nothing came up that got into what im talking about.
So I have been wondering for some time now about some of the details regarding wing flex. Why did older aircraft not really experience this where as most newer large aircraft have in some cases extreme flexing of the wings? For example I do not recall seeing aircraft such as the DC-10, L1011, 707, A300, even the classic 747s with very large wings had minimal movement of the wings. Sure they bounce up and down in turbulence, but im more so talking about heavy takeoffs where you see those wings flexing and doing so much work lifting all that weight. It seems that the first large aircraft that had wings that really flexed was the 767. Nowadays aircraft like the 744/748, 787, A330 etc etc have wings that move significantly depending on the phase of flight and weight etc etc.
So with all that said what has changed in the materials and design of wings over the years that causes such significant movement of the wings and larger aircraft starting with the 767? I'm just taking a guess here, but were older aircraft over engineered or something along those lines? How can an airplane such as a DC-10 or a 747-100 with such large wings have such minimal flex even on max weight takeoffs?
Thanks for any information regarding this subject.