August: Well, it's sort of hard to overlook the fact that we dropped two bombs in August 1945. And then there's the Berlin crisis that heated up with the construction of The Wall in 1961.
Still, I'm going to pick the 2007 munitions transfer incident -- a weapons crew at Minot Air Force Base in North Dakota mistakenly loaded six nuclear-armed cruise missiles onto a B-52 bomber, which then flew the nuclear weapons across the country to Barksdale Air Force Base in Louisiana. The nuclear weapons were unsecured for 36 hours. The explanation is simple: the event occurred immediately prior to a four-day weekend. Somehow, I imagine Loverboy's "Working for the Weekend" blaring in the bunker as the munitions team mistakenly grabs the real nuclear weapons to load on the B-52.
September: This is another month with several big scares. There's the 1980 event in Damascus, Arkansas, when a worker accidentally dropped a wrench into an ICBM silo, puncturing a Titan II missile. It eventually exploded, blasting a 750-ton silo door a quarter of a mile away and launching the nuclear warhead into the air. (No worries, it was recovered.)
But that's nothing compared to the 1957 accident near Kyshtym in the Soviet Union. The accident actually occurred at a closed city associated with the Soviet nuclear weapons program. A cooling system in a tank with 80 tons of liquid radioactive waste failed. The temperature rose suddenly and the tank exploded, sending a plume of radioactive nastiness like cesium and strontium over hundreds of kilometers. Until the Chernobyl meltdown in 1986, this was the worst nuclear accident in history; it ranked a 6 on International Nuclear Event Scale (INES). Chernobyl and Fukushima were INES 7 events.
I was surprised, in writing this list, how much I remembered correctly, as well as how much I did not remember at all. I've been careful to source the short accounts accurately, but perhaps an error has slipped in here or there. And, as I say, this is hardly a comprehensive list. So, I'll be encouraging readers at my blog, ArmsControlWonk.com to offer their favorite nuclear weapons mishap, comment on these or just wax philosophic about the epistemology of the "close call."
And Happy Halloween everyone.