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W54

en.wikipedia.org

46 pointsthunderbong33 comments

Since the range of the W54 fired from a recoilless gun is only a mile or two, what does the operator who personally performed the firing do afterwards? Start driving away at a high rate of speed?

How can I find out the degree and risk of radioactive fallout from a warhead equivalent to 2 - 10,000 tons of TNT?

Maybe don't fire on a windy day from downwind..

> Since the warhead also posed a threat to the crew firing it, the Army recommended that soldiers manning the Davy Crockett select firing positions in sheltered locations, such as the rear slope of a hill. Soldiers were also encouraged to keep their heads down to protect themselves from the warhead’s detonation.

https://armyhistory.org/the-m28m29-davy-crockett-nuclear-wea...

https://en.wikipedia.org/wiki/Davy_Crockett_(nuclear_device)

According to the nukemap calculator if you're ~1km away in the open you'd be fine, and firing from cover (e.g. behind a berm or hill) you could be as close as 200m away with hearing protection and make it out alive so long as you immediately run upwind.

ie. good luck, you will be remembered

https://nuclearsecrecy.com/nukemap

At 1kt (max for the W54?) most of the effects are under 1 km: eg the radiation radius is only 0.84 km. Looks like if you shoot 1 mile away up wind, take cover from the flash, and then run away upwind you'd be fine with some hearing protection.

Sorry to be a pedant, and I also want to confirm my understanding is correct (yes, I've attempted checking definitions, but.. :)

In this case I think firing the device upwind would be ill-advised, as then the fallout will be blowing back to you.

Edit: thank you for the correction @erikerikson! Noted, and best wishes!

You seem to have reversed the terms.

Being upwind means the wind is blowing away from you towards your target and proceeds past your target further away from you.

Parent is right too, I mixed up one of them. I should have said: shoot toward s downwind and run away towards upwind.

Ah, indeed you did. My brain slipped over that, thank you for helping me see it.

I always assumed firing one of these things was a suicide mission, but some NATO guy on Quora has suggested otherwise, and it seems pretty convincing.

https://www.quora.com/Would-the-Davy-Crockett-tactical-nucle...

Basically, even though the W54 had a max yield of a 1kt, the Davy Crockett used a warhead with a far lower yield, as low as 10 tons

The Davy Crockett variant seems to just have had a yield of 20 tonnes. Per nukemap (https://nuclearsecrecy.com/nukemap/ ) the fatal radiation range (of 500 rem) is like 500 meters. If you fire from, say, 5k the radiation exposure should be significantly lower. I don’t know how the radiation exposure scales over distance, but if it’s an inverse square law that means at 5k you’re getting like 5 rem. Which isn’t great, it’s like the equivalent of a CT scan

Didn't know the mini nuke in Fallout was actually real: https://fallout.fandom.com/wiki/Mini_nuke

That paratrooper image is very Doctor Strangelovian

Imagine being that guy though, so few humans will ever have such an awesome portrait

As is the Fulton Recovery System used to airlift enemy soldiers (and friendly animals) in Metal Gear Solid V:

https://en.wikipedia.org/wiki/Fulton_surface-to-air_recovery...

Something like this[1] might come in handy for tracking one of those down, should it become lost somewhere.

Alternatively, if you just want to look for a radiological signal, you could use one of these[2].

[1] https://patents.google.com/patent/US11892419B2/en

[2] https://www.caen.it/products/gamon-drone/

that photo of a paratrooper diving with one of these between their legs has dr. strangelove energy.

And who exactly signs up to jump out of a plane with a nuclear bomb strapped to them?

SASR's, and other similar types.

Wouldn't you? Why not??

Given the number of broken arrow incidents, it’s remarkable that a random city hasn’t been terrorist nuked or at least dirty bombed yet. Obama made a big deal about warning the world about the risks of nuclear proliferation. He told us that al Queda and ISIS have tried to acquire weapons of mass destruction including nuclear.

I literally live in fear that one day I’ll wake up to find that some big city is just gone and that the world is about to go through some real authoritarian shit in the wake of it. Imagine Chicago getting nuked from some terrorists and then no one takes responsibility right after. Trump would start WW3.

I’ve had the idea to write a book about this scenario (or ideally a mod for a better version of hoi4) called “Good Morning America” about the nation responding to this exact scenario.

Because every nuclear power developed their own enrichment processes and bomb technology, their bombs have different isotope ratios in the fallout. It's possible to analyze the fallout to determine where the bomb came from. That might not tell you who is responsible (as the weapon may have been stolen), but it would at least tell you which country's nuke it was.[1][2]

Also, one nuke isn't as destructive as you might think. If you play around with nukemap, you can see that a 50 kiloton warhead detonated in Chicago would be the worst attack in US history, but the city would not be gone. Around 5% of the population would be killed and another 7% would be injured.[3] Remember that the two cities that were nuked took about 10 years to rebuild, and that was in a country that had lost most of its infrastructure and manpower in a devastating world war.

1. https://trace.tennessee.edu/ijns/vol2/iss3/6/

2. https://www.science.org/content/article/surprise-nuclear-str...

3. https://nuclearsecrecy.com/nukemap/?&kt=50&lat=41.8699304&ln...

Who's going to deploy a 50kt warhead? A DF-5A (I think the mainstay of the Chinese arsenal?) would kill just about half the population of Chicago, and that percentage is reduced by the geographical size of the city of Chicago (everybody in the parts of Chicago that people think of as "Chicago" would be dead). The fireball alone would take out Northwestern University in Evanston and Brookfield Zoo out in the western suburbs. Essentially everybody in Chicago would be gravely injured.

Even North Korea's tests have run into the hundreds of kilotons.

Nobody's shooting Chicago to wound. If a nuclear missile hits us, we're not rebuilding.

The linked article is about a backpack nuke. My comment was responding to the possibility of a terrorist group smuggling a tactical nuke or dirty bomb into the country. I was correcting some common misconceptions about such a scenario. I was obviously not talking about a nuclear exchange with China involving DF-5A ICBMs.

Fair enough!

>The fireball alone would take out

Why would the fireball touch the ground? The attacker could destroy twice as much stuff by choosing an air burst.

> Because every nuclear power developed their own enrichment processes and bomb technology, their bombs have different isotope ratios in the fallout. It's possible to analyze the fallout to determine where the bomb came from. That might not tell you who is responsible (as the weapon may have been stolen), but it would at least tell you which country's nuke it was.

A major plot point of Tom Clancy's A Sum of All Fears is exactly this.

A bomb gets lost by the Israelis and acquired by terrorists (Arab nationalists in the book, neo-Nazis in the film) and detonated in Baltimore with the intention of starting a nuclear exchange between the US and the Soviet Union. It turns out the fissile material was made at Oak Ridge, crisis averted, tea^Wcoffee and medals in Washington.

The lack of a terrorist nuclear attack is hardly remarkable. There have only been a few "broken arrow" incidents. Most of them would have caused major damage to the physics package and other key components. Or everything is deep under the ocean, beyond scuba range.

Even if a terrorist somehow obtained a complete warhead in good condition they would have a limited time window to use it. In order to operate reliably, warheads require regular maintenance by skilled technicians, and then every few years the entire thing has to be pulled and remanufactured. This is part of the reason why our nuclear deterrent is so enormously expensive: there's a lot of support infrastructure behind the weapons and delivery platforms.

A radiological weapon (dirty bomb) is a more realistic threat.

We're going to run the experiment sometime. The equilibrium has miraculously held since 1945 but it's not stable, and someday there will be a nuclear exchange. There's no way to put the genie back in the bottle.

One saving grace is that nukes do have a shelf life. They require regular maintenance too. The radioactive core of plutonium or uranium can last for a while, but the various components will degrade. I heard once on the Arms Control Wonk podcast that this could be on the order of like 10 years. Someone could still salvage that to make a dirty bomb, of course, but there’s plenty of easier ways to make a dirty bomb from other radioactive materials

The effort by the nuclear nations to hunt down these weapons is likely significant. As it their efforts to stop proliferation in general. It is also something the US, Russia and everyone else can agree on. Just consider the number of Iranian physicists that have driven off the road under tragic circumstances… How would non-state actors be hunted, no doubt intensively.

It will take a much bigger nuke than a backpack to make a big city "just gone" in the modern world.

Every now and then, ships full of explosive material blow up in a coastal city, with yields much larger than what a small nuke like W54 can produce. Texas City. Tianjin. Beirut. They were tragic accidents with many casualties, but nowhere near strong enough to wipe a big city off the map. Reinforced concrete is incredibly tough. There's an old building in Hiroshima that survived only 150 yards from ground zero. WW2-style firebombing is much more effective at rm -rf'ing cities than most nukes we have today.

Whether or not the man at the top will take the explosion as an opportunity to attack another country, now that's a much more serious concern.

That is similar to the premise of the TV show Jericho [0]. Not a great show, but its worth a watch if you like that sort of thing.

[0] https://en.wikipedia.org/wiki/Jericho_(2006_TV_series)

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