How B52's were designed

How does an old airframe like the B-52 (last produced in 1963) overcome metal fatigue ...

https://www.quora.com/How-does-an-old-airframe-like-the-B-52-last-produced-in-1963-overcome-metal-fatigue-from-so-many-take-off-landing-cycles

Very interesting little article describing, in the latter half,  how this mighty plane was designed in a few all-night sessions in a hotel.