Imagine walking into the Burbank offices of the Lockheed corporation in 1953, where the engineers were hard at work on a new transport plane, and telling them that the plane they were drawing up would still be in heavy use more than sixty years later.
Mind you, some of the guys in the room were alive when the Wright Brothers first flew. The entirety of manned powered flight had happened within their lifetime, and you are telling them that the cargo plane they were designing would be used as a laser-armed gunship in the world of 2019. (Well, you'd have to say "energy ray-armed", because the word "laser" wouldn't even be coined for another half dozen years.) In fact, it would not just still be in heavy use, it would still be being built, which would have sounded as fantastical to them as someone still making Wright Flyers in '53.
(H/T to Weaponsman.)
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