According to the article, the W69 would not have detonated their nuclear payload, but there was a significant risk of their conventional explosives (used to compress the nuclear mass for detonation) as well as rocket engines igniting and spreading the radioactive payload in a "dirty bomb" manner.

Also, in the other type of bomb that was on board there apparently was a design flaw that could've actually triggered the nuclear detonation after prolonged exposure to extreme heat.

> Also, in the other type of bomb that was on board there apparently was a design flaw that could've actually triggered the nuclear detonation after prolonged exposure to extreme heat.

So who found that bug and how? I mean... Yikes.

It was a known issue that setting explosives on fire makes them...quite unhappy (hence why nowadays the detonators mostly use insensitive explosives [1]).

In the context of a partial/asymmetrical detonation around a warhead - they tried it! [0]

0: https://en.wikipedia.org/wiki/Project_57

1: https://en.wikipedia.org/wiki/Insensitive_munition

If the conventional explosives around a warhead go off in an uncontrolled manner then they are almost certainly not going to kick off a nuclear chain reaction. Things have to happen at a very specific time.

But what you're going to get is a massive plume of weapons grade plutonium flying in all directions. Depending on where this happens and the wind this could be the end of a few million people.

If you read the literature it turns out that's in some cases wishful thinking. You'd never get full yield, but no chain reaction turns out to not be guaranteed in the older designs.

Can you point me towards what you read on this outside of the article? Not doubting you it's just been like 500 years since I studied nuclear chem and I'm not sure what literature you're talking about.

A good introduction is Eric Schlosser's Command and Control. For the points here the concept of one-point safe is the idea of if a nuclear device is likely to detonate in an uncontrolled situation. A good definition I found was[0]:

> What is one-point safe?

> Apart from preventing unauthorized use, it is equally important to ensure that the weapons do not explode accidentally. For example, if it is accidentally dropped dur­ing transportation (such incidents have occurred), it should not explode. A nuclear weapon is one-point safe if, when the High Explosive inside the weapon is initiated and detonated at any single point, the probability of producing a nuclear yield exceeding 4 pounds TNT equivalent is less than 1 in one million.

A surprising number of early nuclear devices were not one-point safe.

[0] http://www.nucleardarkness.org/nuclear/nuclearandconventiona...

That only applies to most modern warheads. Older warheads had much less safety features.

W69 was designed in early 70s when they had much less safety features. W69 had a design error that made it nuclear detonation possible in the event of a fire.

An even more dangerous bomb was the Violet Club [1], an airplane couldn't land with one on board.

[1] https://en.wikipedia.org/wiki/Violet_Club

They literally put a bag of ball bearings into the hollow interior of an enriched uranium sphere (to prevent its accidental implosion which would set off the bomb). Even scarier they didn't really know if this would actually work, but it was better than doing nothing.

The Atomic Weapons Establishment was doing Minimum Viable Product before it was cool to build MVPs!

More seriously, most of the reason they cobbled this together was because the US suddenly cut off access to research after WW2 (because of the McMahon Act [2]) and the UK had to look as if they were an independent member of the Big (nuclear) Boy's Club. Between this and the Windscale fire [1], that could've led to absolute disaster.

1: https://en.wikipedia.org/wiki/Windscale_fire

2: https://en.wikipedia.org/wiki/Atomic_Energy_Act_of_1946

"At least one accident, dated 1960, was reported in the press when the plastic bung was removed and 133,000 steel ball bearings exited onto the aircraft hangar floor, leaving the bomb armed and vulnerable." Wow. Real Dr Strangelove stuff.

No. That's how only one bomb worked (little boy). All other bombs use the implosion technique. One mass and the implosion changes its shape/density.

That's covered in the article:

> If this had happened in the 1980 accident, the rocket motors in the SRAMs, as well as the conventional explosives inside their W69 warheads, used to initiate the thermonuclear reaction, would very likely have exploded. While this may not have triggered a nuclear explosion, it would have thrown a plume of highly radioactive plutonium into the air, easily covering a 60 square mile area, which would have included parts of North Dakota and Minnesota.

There's a part further down where they mention that the other type of bomb had a design flaw that could have led to a nuclear detonation under the conditions.

"Oops"

The high explosives surrounding the core are triggered by electronic firing (today). I assume this is the most "weak" part of the firing chain physically.