I'm not sure why the US military is still flying these dinosaurs....and then strap on new engines on this dying beast to make it last longer? Thats akin to putting an new LS3 motor in a broke ass 1957 Chevy. Sure it sounds cool and hauls ass, but will the rest of the parts keep up with the motor?
Speaking of B-52's, back in 1961 when the BUFF's were fairly new SAC had one break apart in flight near Seymour Johnson AFB in North Carolina. It was carrying two Mark 39 thermonuclear bombs with each bomb capable of 3.8 megatons. One of the bombs went deep into the ground but the other deployed its parachute and had completed its full arming sequence save one last switch.
(Historical note: it was 24 January 1961, President Kennedy's 4th day in office)
https://en.wikipedia.org/wiki/1961_Goldsboro_B-52_crash

Looks like Hollywood is now going to make a movie about it: https://variety.com/2018/film/news/nuclear-bomb-movie-hacksaw-ridge-producer-1202985476/