No, most of the B-52s currently in service are well over 50 years old: "The last production aircraft, B-52H AF Serial No. 61-40, left the factory on 26 October

No, most of the B-52s currently in service are well over 50 years old: "The last production aircraft, B-52H AF Serial No. 61-40, left the factory on 26 October 1962." https://en.wikipedia.org/wiki/Boeing_B-52_Stratofortress#Variants https://en.wikipedia.org/wiki/Boeing_B-52_Stratofortress#Var... Another weapons system: the M1 heavy machine gun is still heavily used, e.g., one on every Abrams tank, 4 or 6 on every aircraft carrier, and ISTR all of the US's inventory of it was made before and during WWII. I think maybe they use barrels that were designed more recently.