The Fifth Risk by Michael Lewis:
“Broken Arrow” is a military term of art for a nuclear accident that doesn’t lead to a nuclear war. MacWilliams has had to learn all about these. Now he tells me about an incident that occurred back in 1961, and was largely declassified in 2013, just as he began his stint at DOE. A pair of 4-megaton hydrogen bombs, each more than 250 times more powerful than the bomb that destroyed Hiroshima, broke off a damaged B-52 over North Carolina. One of the bombs disintegrated upon impact, but the other floated down beneath its parachute and armed itself. It was later found in a field outside Goldsboro, North Carolina, with three of its four safety mechanisms tripped or rendered ineffective by the plane’s breakup. Had the fourth switch been flipped, a vast section of eastern North Carolina would have been destroyed, and nuclear fallout might have descended on Washington, DC, and New York City.