Check this out - https://nationalinterest.org/sites/default/files/main_images/North_American_XB-70_dryden_test.jpg It's the XB-70. Absolutely beautiful. Wikipedia says it was launched in 1964, or at least that's when test flights were started.

Now clearly we are not using it now so it couldn't have been too ahead of it's time, but what do you think we have now that is truly functioning?

Even the YF-23 Widow Maker that lost to the F22. I keep reading that, that plane was far far FAR ahead of it's time, some are even saying it was a 6th generation fighter... Think about that, a 6th gen fighter built in 1989. https://farm9.staticflickr.com/8671/16497532877_521de4a97f.jpg

I am no airplane historian but it's just now I am getting into reading about them. I cannot believe how old some of these designs are. It's incredible.