Title says it. Really curious how we’ve escaped this kind of occurrence anywhere in the world, for the last ~70 years.
In: Engineering
A. There are multitudes and multitudes of safeguards to prevent accidental detonating. However…
B. A far more worrying statistic is how many nukes have been accidentally deployed, *and cannot be located*…
You don’t just make a nuclear bomb. It takes an extraordinary amount of effort to produce one, and just as much expertise. You don’t just happen across them.
Such an investment is well cared-for, and countries go to great lengths to keep their nukes secure. The number of missing nuclear warheads is not zero, but it is very small. Among them, most are certain to no longer function. Remember, nuclear weapons are very very difficult to set off. Damaging one just renders it more inert.
Nuclear weapons are, by design, nearly impossible to set off accidentally. You need a very specific sequence of events to happen in exactly the right order at exactly the right times, which is extraordinarily unlikely to happen without deliberate human intervention.
A damaged bomb becomes more dangerous because it is full of carefully contained explosive chemicals that are just begging to detonate when the right bump comes along.
A damaged nuclear weapon becomes a very expensive and possibly radioactive paperweight. Unlike a traditional explosive, the device inside requires a very specific and detailed arming and detonation sequence that must maintain a very tight timing window and configuration to make the nuclear material go critical in exactly the right time at the right shape.
They will not go off by accident. You’d need a dozen very peculiar *accidents* in a row to make that happen.
One of the saving graces of nuclear weapons is that the conventional explosion to compress the plutonium sphere has to be *really* symmetric. Like really really symmetric. Plus the thingy that fires the neutrons in right at maximum compression has to be timed to within a few microseconds. Both of these things are actually pretty hard to do. If the conventional explosion isn’t symmetric, you just get a mess with plutonium blasted around, but no yield. So it’s a cleanup problem, but not much of a bang. If the neutron source doesn’t work, yet get a lot less yield and it’s probably what’s called a fizzle where yield is too small to do much.
An aging weapon having a problem is really unlikely to work correctly and will just make a mess. Bad if you are right there, but not a big deal.
To cause a nuclear explosion requires a very carefully and precisely timed sequence of events using triggering conventional explosives, and and extremely precise geometry of parts all to work just right. This is part of what makes it very hard to design a nuclear weapon. If the triggering conventional explosives accidentally go off, it is exceedingly unlikely they would go off in just the right way required to trigger a nuclear explosion. Essentially you would end up with a small dirty bomb, which would spread some radioactive material over a not all that large area. It would be annoying and awkward to clean up the mess, but it would be nothing like an actual nuclear detonation.
Because we set off over 2000 of them deliberately in semi-safe locations to make them safe.
A very large portion of the nuclear tests that occurred during the cold war were so called “safety tests”. They conducted often dozens of tests for individual warhead types to see what would happen if they caught on fire, if one detonator went off, if it crashed into the ground at high speed etc. They would not enter service until they had passed these tests.
Many of the earliest nuclear bombs who did not undergo this sort of safety testing were so unsafe they had to be stored in a disassembled state, only to be put together when they were intended to be used.
To set off a nuclear weapon requires a lot of things to go *correctly* rather than something to go wrong, or be caused by accident. A poorly-maintained old nuclear weapon is less likely to go off than one that is well-maintained. An improper nuclear detonation would be more like a fizzle than a massive explosion, making it more akin to a dirty bomb with conventional explosives.
The problem is not so much that we could accidently set one off, but that we might improperly blow one up, causing an incredibly toxic and localised hotspot of contamination plus plumes of radioactive material, possible groundwater contamination and almost certain uninhabitability without intensive and expensive remediation.
We’ve avoided it [by pure luck](https://en.wikipedia.org/wiki/1961_Goldsboro_B-52_crash). Since then the arming mechanisms have evolved.
Nuclear weapons aren’t simple weapons.
They are intricate, complicated devices with dozens of parts that all need to work in just the right way to go boom.
And the people storing them tend to be really good at their jobs. Accidental explosions just don’t happen in long time storage.
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