....interesting post...! a bit of aviation history....if I remember correctly, the United State Army Air Forces (yes, with an “s”) never did completely fix the engine fire problems on that great aircraft...I seem to remember reading some years ago that engine fires were always a concern to B-29 crews....
Here’s a video on the British efforts to make the Lancaster a nuclear bomber:
https://www.youtube.com/watch?v=5XX9ptCNpik
I had an uncle, now buried at Arlington, who was a B-29 navigator in WWII and in Korea. He was always a prankster and joker...he had a sense of humor about everything. Once he was visiting when we were kids and I showed him a model B-29 I was working on. It was the only time in my life I saw him drop his jovial persona, as you could tell he was overcome with a wave of memories and reverence for the airplane.