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United States discloses nuclear warhead numbers; restores nuclear transparency

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Re: United States discloses nuclear warhead numbers; restores nuclear transparency

#41

Post by silverquiet »

openasocket wrote: post #37
lmm wrote: post #19

Earlier quoted context omitted.

> Since the alert window is under 10 minutes, you can't keep a liquid-fuelled rocket permanently fueled so the Minuteman was developed as a solid rocket fuel booster. Huh? The Titan II was developed to do precisely that and worked that way for decades, they were liquid-fuelled and kept fuelled in their silos.

Liquid propellants are generally less stable than solid fuel. I had read in multiple places (from reputable sources) that you generally couldn’t keep liquid missiles permanently fueled like that. The propellants are extremely corrosive and dangerous. But you are right that the Titan II is liquid fueled and was kept permanently fueled in the silo. I’m not entirely sure how to resolve those two facts. The Wikipedia pag…

There was an incident where a technician dropped a large socket down a silo that impacted the side of a Titan missile and set off a chain of events that ended in an explosion that nearly detonated a nuclear bomb on US soil.

Re: United States discloses nuclear warhead numbers; restores nuclear transparency

#42

Post by sitharus »

jmyeet wrote: post #14
FredPret wrote: post #2

Max warheads = 31k Current warheads = 3.7k I wonder how long a nuke in storage lasts - ie, how much work does it take to maintain a stockpile of x nukes, and if you can turn those swords into ploughshares relatively easily.

So this varies depending on what kind of nuclear weapon is and the delivery system. The major deterrant is the LGM-30G Minuteman III [1]. Most of our rockets use liquid propellants. Since the alert window is under 10 minutes, you can't keep a liquid-fuelled rocket permanently fueled so the Minuteman was developed as a solid rocket fuel booster. There's a whole team responsible for maintaining the boosters and warhead…

> you can't keep a liquid-fuelled rocket permanently fueled so the Minuteman was developed as a solid rocket fuel booster.

You absolutely can! The Soviet doctrine was to use storable liquid propellants in their ICBMs - typically unsymmetrical dimethylhydrazine (UDMH) as the fuel and nitrogen tetroxide as the oxidiser. I don’t know if they need the fuel/oxidiser replaced periodically but that combination is storable for over a decade.

The US went with solid rockets as they are more reliable - no turbines or valves etc - at the expense of performance, but the US perfected making large solid rockets before the USSR. The USSR however perfected oxidiser-rich staged combustion which extracted a lot more performance.

Storable liquid propellants are still used on satellites and deep space missions that need to perform large course corrections during their missions.

Re: United States discloses nuclear warhead numbers; restores nuclear transparency

#43

Post by hypeatei »

llamaimperative wrote: post #32
JumpCrisscross wrote: post #17

Earlier quoted context omitted.

> no form of full scale nuclear war where the production apparatus for anything becomes a factor Where full nuclear war means a full exchange of strategic fire, yes. For tactical nukes or bombardment of a non-retaliating state, less so.

It's not clear there's any such thing as "tactical nukes" given that they're strategically useless, and it's actually not even clear there's such a thing as nuclear exchange that isn't full scale war. At least as told by Ellsberg in the Doomsday Machine, there was literally no mechanism for the US to launch a partial nuclear attack.

> no mechanism for the US to launch a partial nuclear attack

Yep, the trajectory to North Korea (from US mainland) has to pass over Russia and the Russians have to trust that it's not coming for them.

Not that Russia would be okay with us striking NK in the first place, but you get the point.

Re: United States discloses nuclear warhead numbers; restores nuclear transparency

#44

Post by lumost »

transcriptase wrote: post #11

Every time I’ve seen nuclear stockpiles and the reduction thereof discussed, I’ve wondered: Assuming for some reason the United States needed to ramp back up to an absurd number of warheads (ignore the MAD/political practicalities), how quickly could they do so? What’s the lead time or rate limiting factors in production? Because if they could start churning out a dozen or a hundred a week within a short period of ti…

The final cost of an h-bomb at industrial scale was estimated at 10k in the 1960s (for low yield).

However for practical purposes. One simply needs enough missiles and warheads of sufficient yield to overwhelm opposing interceptors, avoid risks of pre-emptive strike/miss-fires+500.

After that there are rapidly diminishing returns for more warheads.

Re: United States discloses nuclear warhead numbers; restores nuclear transparency

#45

Post by tyingq »

llamaimperative wrote: post #32
JumpCrisscross wrote: post #17

Earlier quoted context omitted.

> no form of full scale nuclear war where the production apparatus for anything becomes a factor Where full nuclear war means a full exchange of strategic fire, yes. For tactical nukes or bombardment of a non-retaliating state, less so.

It's not clear there's any such thing as "tactical nukes" given that they're strategically useless, and it's actually not even clear there's such a thing as nuclear exchange that isn't full scale war. At least as told by Ellsberg in the Doomsday Machine, there was literally no mechanism for the US to launch a partial nuclear attack.

I take tactical to mean something like "Depends a lot on who/where/why, how much primary and collateral damage, and so on. You may be right that any use of any nuclear weapon turns into a global doomsday. It's hard to say unless it really happens. I'm often surprised that terrible war related incidents end up not escalating beyond the general region where they happened.

Re: United States discloses nuclear warhead numbers; restores nuclear transparency

#46

Post by skellington »

JumpCrisscross wrote: post #17
skellington wrote: post #15

Earlier quoted context omitted.

There is no form of full scale nuclear war where the production apparatus for anything becomes a factor.

> no form of full scale nuclear war where the production apparatus for anything becomes a factor Where full nuclear war means a full exchange of strategic fire, yes. For tactical nukes or bombardment of a non-retaliating state, less so.

I dunno...too hypothetical a question to answer, since we already have enough nukes to destroy everything and nobody is going to reduce their arsenal to one.

Re: United States discloses nuclear warhead numbers; restores nuclear transparency

#47

Post by BMc2020 »

devwastaken wrote: post #28

Nobody asks how many anti nuke missiles. :)

Funny enough, I know a little bit about this one. We have them, but they are all come-from-behind missiles, so the launch site has to be as close to Russia (or wherever) as possible, which angers the Russians.

The head-on hit-a-bullet-with-another-bullet-is missile still impossible, although many would like us to believe they are already here. Nuh uh.

Plus those are still useless against nukes delivered inside ton of cocaine.

Re: United States discloses nuclear warhead numbers; restores nuclear transparency

#48

Post by GemesAS »

transcriptase wrote: post #11

Every time I’ve seen nuclear stockpiles and the reduction thereof discussed, I’ve wondered: Assuming for some reason the United States needed to ramp back up to an absurd number of warheads (ignore the MAD/political practicalities), how quickly could they do so? What’s the lead time or rate limiting factors in production? Because if they could start churning out a dozen or a hundred a week within a short period of ti…

Pit production is likely the rate limiting factor.

We disassembled a bunch of AFAPs so have a lot of weapons grade plutonium around. But Pu is nasty to work with & Rocky Flats--the previous pit production facility--closed down years ago. Pit production moved to Los Alamos but it is at a much reduced capability.

Also, Pantex--where nuclear weapons are assembled--isn't exactly the model for speed & efficiency.

Re: United States discloses nuclear warhead numbers; restores nuclear transparency

#49

Post by MengerSponge »

philipkglass wrote: post #13
Loughla wrote: post #10

Earlier quoted context omitted.

How do you know all this? Is that a hobby or a job?

It's a hobby. I read a lot and I have enough formal education to digest primary sources (mostly; my highest qualification is auditing a neutronics course while in grad school). If you too would like to know way more about nuclear weapons than is useful in civilian life, I'd recommend reading: Richard Rhodes, The Making of the Atomic Bomb The nuclear weapons FAQ, authored by Carey Sublette, a hobbyist researcher who i…

Let me add "Inventing Accuracy" to your list of recommended reading. It's fascinating, and it's a powerful microscope to reveal the relationship between strategic need and technological development

https://mitpress.mit.edu/9780262631471/inventing-accuracy/

Re: United States discloses nuclear warhead numbers; restores nuclear transparency

#50

Post by fshbbdssbbgdd »

hypeatei wrote: post #43
llamaimperative wrote: post #32

Earlier quoted context omitted.

It's not clear there's any such thing as "tactical nukes" given that they're strategically useless, and it's actually not even clear there's such a thing as nuclear exchange that isn't full scale war. At least as told by Ellsberg in the Doomsday Machine, there was literally no mechanism for the US to launch a partial nuclear attack.

> no mechanism for the US to launch a partial nuclear attack Yep, the trajectory to North Korea (from US mainland) has to pass over Russia and the Russians have to trust that it's not coming for them. Not that Russia would be okay with us striking NK in the first place, but you get the point.

Are you saying that just because the great circle from US to NK goes over Russia? Can we not fire on a less optimal trajectory? Or from a submarine?
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