Nuclear Duds

[Silencer]

Does anyone know if there were any cases where a nuclear bomb actually didn't go off?

I know that this was a major concern in the first two historic bombings of Japan and one of the factors that contributed to the lack of a warning being issued beforehand to Japan.

A quick search of teh interwebz led me to this, but actually there are only botched under-yield test explosions here. Also, this document has some yields listed as "none", are those duds?

I think that the Las Palomares incident comes closest, although those bombs weren't actually armed to go off anyway.

And no, I am not trying to disprove Megaton, it's just that I have only seen/heard of unexploded nukes in fiction so far

 

[horse]

most of the "duds" seem to have been partial explosions due to bad design, or physical "explosions" happening due to accidental explosions. i have neither read nor heard about any duds lying around... no wonder, since building an atomic bomb is extremely expensive. so, letting a half-assed atomic bomb build off would be as intelligent as fueling jets with just enough gas to let them fly into the enemy area, where theyd run out of fuel. there might have been duds while testing, but i do think those bombs would have been fully recovered if only for the very expensive materials.

anyway, the sources you brought up in your post are way better than mine, so i am more or less using arguments of the "common sense" category.

finally: the reasons why there were no warnings issued to japan, might not have been primarily of technical background.