Nuclear War Failure Statistics

What percentage of ICBMs will explode in their silos?

What percentage of nuclear weapons will hit their targets?

What percentage of nuclear weapons that hit their targets will actually detonate?

Just curious.
 
Pretty much unknowable.

THere have been some tests, but I doubt that you can trust that the ICBMs in question didn't recieve special attention before launch.

I assume worse numbers for the SOviets, but don't trust that either would be good.

Now bombers?

Those should go off pretty well.

After all the various Air Forces fly the planes around quite often, and human pilots can correct as they go.
 
I assume that the bombers usually work well, right until they are shot down.

But usually a major part of nuclear war is ICBMs launching. And I'm kind of annoyed with all the alt-hist nuclear wars involving a very success rate in getting countervalue and counterforce payloads to work. Nuclear war always seemed to me to be a game of russian roulette, except the trigger is pulled six times, and most of the bullets are shoddy.

And to my understanding, mass-production of nuclear bombs lead to a major decline in quality.
 
Well this link gives some statistical analysis of US weapon failure rates. With the bottom line being on the order of 1-2% for warheads and 2-4% for missiles. The expected failure mode would be failure to detonate for warheads and failure to launch for missiles. No indication of any explosion in silo as an expected failure mode.

Now this is just one paper and I had heard much higher possible weapon failure rates - on the order of 25-30% for warheads, but I don't have the books with me right now and that might have been for earlier weapons.
 
Well this link gives some statistical analysis of US weapon failure rates. With the bottom line being on the order of 1-2% for warheads and 2-4% for missiles. The expected failure mode would be failure to detonate for warheads and failure to launch for missiles. No indication of any explosion in silo as an expected failure mode.

Now this is just one paper and I had heard much higher possible weapon failure rates - on the order of 25-30% for warheads, but I don't have the books with me right now and that might have been for earlier weapons.

2%-4% failure for missiles...

Bear in mind....

(1) No missiles have afaik, ever been tested 'cold', ie without any preparation. Test shots are simply too expensive, and reliability isnt actually the reason for them.

(2) No missile has (for obvious reasons!) flown over the pole with its variable gravitational and magnetic anomalies.

(3) There is the issue of crews simply not firing (unlikely, but it counts as a failure)

(4) Fratricide and EMP pulses affecting the warheads. carbon-carbon does not respond well to being flown through anything at reentrry speeds.

Of course, given the number of missiles available, even high failure rates isnt an issue. In fact, for MAD, high failure rate is an ADVANTAGE!. If noone is certain how many missiles will actually go boom, you're even less likely to use them.

What it does mean is that a substantial percentage of targets will survive the missile strikes. Note that even wih a missile force amply capable (on paper) of reducing each other to glass, both sides also employed bombers to deliver followu-up strikes. You can read what you wish into what this says about missile reliability.....:)
 
What percentage of nuclear weapons will hit their targets?

Seeing as others have addressed the other two questions...

Each weapon type has a "Circular Error Probable", or CEP. CEPs are usually classified but there are unclassified guesstimates available - for example, wikipedia gives the Minuteman III a CEP of 150 meters, although I believe that was before some recent upgrades. That means that half of the warheads will land closer than 150 meters to the target, and half will land further than 150 meters.

At the time, the Minuteman III was considered a very accurate missile. Early ICBMs had CEPs measured in miles. There have been proposals for Maneuverable Reentry Vehicles that could get CEP as low as 10 meters. Bombers tended to have significantly better CEPs than missiles.

All of these figures are somewhat uncertain, based on prepared missiles firing into the Kwajalein test range. As Astrodragon mentioned, accuracy will presumably be degraded by firing cold, firing over a different trajectory, and the general chaos of a nuclear war.

Whether or not 150 meters counts as a miss depends on what you're trying to kill and how big your warhead is. Against a city, it's probably close enough. Against a hardened missile silo, it may not be. That's part of why counterforce planning assumed multiple warheads targeting each silo.
 
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CalBear

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Based on general solid fuel missiles, you can assume around a 20% total failure rate, either failure to ignite or catastrophic failure during boost (this would be higher for liquid fueled missiles, which are far more twitchy, as can be seen in civilian launches), assuming a good PM process is in place, which is a rather large assumption especially for Soviet/Russia systems. Call the actual failure rate 33%.

Warheads are VERY reliable. They are heavily tested, at least in the U.S. inventory (one reason the nuclear stockpile is so damned expensive to maintain) Failure, as in no detonation, would be no more than 5%.

The real question is accuracy. The over Pole launch is very different from anywhere test are conducted. I always thought they should fire some missiles w/o physic packages over Antarctica just to get some sort of feel for the bias issue, but the politics of that are such that it won't ever happen. The real problem would be in the counter-force weapons, which need to be pretty much dead on. Population targets, well, a 2,000 meter miss with a 450KT warhead doesn't really matter all that much.

There is also the fact that most of the strikes against population/strategic targets, at least on the Western side, would be SLBM, many of which would not require an over Pole flight path which would greatly improve accuracy. U.S. SLBM are also MIRV.

When you throw in counterforce strikes, other enemy action (a SSBN getting potted by the odd fast attack boat) and the fact that a number of crews just flat won't launch their weapons, it would be a surprise if 25% of the total weapons actually hit their targets. That is mainly why there are enough weapons to kill the Planet five or six times over..
 
Interesting. I once heard that a 70% failure rate with minuteman missiles was expected, partly because contractors cheap out and also because it's difficult to test a missile in the US. Of course that was only hearsay.

the fact that a number of crews just flat won't launch their weapons, it would be a surprise if 25% of the total weapons actually hit their targets.
Unlikely. Nuclear crews aren't cerebral types, and I don't think there is anything more detached from mass murder then nuclear launch procedures.


Kind of curious, if testing over the pole was so important, why hasn't there been any missile launches over the Antarctic to test the south magnetic pole's effects? There is a lot of ocean and islands around the Antarctic, so it won't be like firing into Siberia.
 
The Antarctic Treaty System banned all military activity over the continent and its environs, and it specifically mentioned nuclear testing as being prohibited for all signatories. The US did sign that treaty, so testing was out of the question. Even if they were just testing the missiles without warheads, the ban on all military activity would've trumped that.
 
The Antarctic Treaty System banned all military activity over the continent and its environs, and it specifically mentioned nuclear testing as being prohibited for all signatories. The US did sign that treaty, so testing was out of the question. Even if they were just testing the missiles without warheads, the ban on all military activity would've trumped that.

The treaty is only in force for the region of the earth below sixty degrees south. Launch a missile from 58 degrees south to 59 degrees south.
 

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The Russians did and do fire missiles cold or as cold as possible. The missile is randomly selected, warheads removed and replaced with test warheads and fired. And I believe they did in fact do live firing on occassion.
 
I once read a breakdown of expected failure rates for each process of a missles mission, the 1-5% failure rate for each process added up to something like only 66% of missiles could be expected to complete their missions. However in reality I think the number would be a fair bit higher, perhaps 80%.
 
I would imagine the submarine-launched missiles have less of a problem because maintaining them is integral to maintaining the ship.

I wouldn't have thought many missiles would actually explode on launch - even if they do of course I don't think the warhead would. More likely would be a clunk-clunk launch where the thing fails to ignite and doesn't leave the silo.

Wasn't there some sort of test done into how many crews would actually fire the missiles if they thought it was for real?

Pinpoint accuracy isn't really necessary when your blast load is in megatons, just getting thereabouts would do it.

Did anyone have EMPs as defensive weapons? And would they have worked? I mean, once launched weren't the missiles basically going where they were going without electronic guidance systems? I thought it was all calculated on trajectory etc

Best Regards
Grey Wolf
 
Did anyone have EMPs as defensive weapons? And would they have worked? I mean, once launched weren't the missiles basically going where they were going without electronic guidance systems?

The Soviet ABM system around Moscow (and probably the US system, before it got dismantled) used nuclear warheads on it's interceptors. Partly to get results from rounds that probably weren't very close, but I do remember reading that the EMP effects were acknowledged as also being an important aspect of this defence.
Unfortunately, although I can't recall the reference, I think this was in a book by Victor Suvorov. He can be a bit biased and unreliable on some points. A degree of caution is probably advisable when considering what he writes.
 
what is the influence of age on the warheads reliability? after all they do contain fissile material, and that tends to produce a certain amount of neutrons, which in turn tend to degrade the surrounding material.
Hence why warheads get refurbished after a certain time.

I could imagine that the older warheads have a higher failure rate.
 
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