Bunker Busters probably failed to penetrate Iranian concrete

by _1tem • 1 year ago

67 95 1 year ago

adrianN2• 1 year ago

Interesting discussion on concrete. I wonder whether additive manufacturing could help create stronger concrete structures.

blangk• 1 year ago

it sounds like it would be great for bunkers

bell-cot3• 1 year ago

Probably - but for a given $budget, the strongest possible bunker might still involve very little additive manufacturing.

bell-cot3• 1 year ago

The HTML title is a better description of the article:

Why the Strongest Bombs Can’t Crack [High] Performance Military Concrete

m_a_g• 1 year ago

I don’t think people realize this is going to escalate the conflict. There are other bunker busters that can do the job, but they are all nuclear.

dragonelite• 1 year ago

Looks like tactical nukes is on the menu, boys...

Is probably what the Russian and Chinese reaction to a tactical nuke usage even if it was for bunker busting.

4gotunameagain2• 1 year ago

Yeah obviously bombing a state is an escalation of conflict.

I wonder how much the US taxpayer paid for 6 B2 bombers to drop 12 mega bombs for the benefit of Israel.

lnsru• 1 year ago

I am not sure about the benefit of Israel. But it was impressive demonstration of power. I mean flying around half globe undetected and delivering huge bombs no one else has. I have hard time calculating dollar value of such future negotiation argument.

skywhopper2• 1 year ago

Over and above the cost of maintaining the B2 fleet, at least $100 million for the mission, logistical support, munitions, plus the reported feint-mission using additional B2s on the westward route.

christophilus• 1 year ago

Not much more than is spent in training missions, I’d guess, and this training is much more valuable.

That said, I’m just a programmer and have no idea.

icameron• 1 year ago

I heard a number of 260 million in an article, if that’s any help.

jddddam• 1 year ago

Israel has already obliterated Iranian air defense and flattened the surroundings.

Can someone tell me why the US or Israel can’t just fly in a Seal Team that goes into the facility, plants a bunch of C4 and calls it a day? They can surely ringfence and defend the area by putting fighter jets and a couple hundred drones in the air while the operation is ongoing.

nmfisher• 1 year ago

Probably because the last time the USA tried something like this, they lost 8 soldiers and about the same number of helicopters.

https://en.m.wikipedia.org/wiki/Operation_Eagle_Claw

ozgrakkurt• 1 year ago

Just making it up but there could be people that are in the army of the country that you are dropping into so they might need to kill each other which will escalate it to another level probably

Muromec• 1 year ago

Sometging something playing too much COD

tyleo• 1 year ago

I’m only guessing here but I feel like the answer is risk.

There’s a big risk difference between boots-on-the-ground and flying over while pushing a button.

nextweek2• 1 year ago

Because the Iranians blocked the entrances with soil. There are satellite photos showing dump trucks at the entrances and the entrances being covered over.

It was a clever move on the part of Iran, because an invading force would need to bring heavy equipment with them, which isn't going to happen.

optimalsolver2• 1 year ago

Just like in the movies!

pragmatic• 1 year ago

You mean cause an international incident...again?

Tadpole91812• 1 year ago

Yes, why can't we "just" boots-on-ground invade one of the most secure locations in another country. I'm sure that won't have any consequences whatsoever and is a totally normal thing to suggest.

potato37328424• 1 year ago

this is going to escalate the conflict.

Sure, if by "this" you mean media and a segment of the population harping on how the strike did little or nothing.

After the strike and before this reporting Israel could justify deescalation by saying the nuclear program was crippled and Iran could justify deescalation by acting like it was no big deal and they lobbed counter strikes to great effect (lol) and the US could justify deescalation with the usual "look what happens to brown foreigners who cross us and our buddies" schtick and from there the matter could be quietly dropped, at least as much as such things can be.

That may all still happen, but all this rhetoric about how the strikes were ineffective is driving things toward escalation.

nkrisc• 1 year ago

But is it true?

lantry3• 1 year ago

The media is reporting the world as it is, not the world as it should be. It's not their job to de-escalate. Kinda silly IMO to blame the people writing articles instead of blaming the people dropping bombs and launching missiles.

0xbadcafebee• 1 year ago

Trump's goal is just to prop up his base, like any normal politician. He dropped a big bomb, made a big announcement, his base will be happy.

Netanyahu's goal is to either occupy or destroy the Islamic world. He's smart enough to know he has to do it in baby steps. He's been working the long game on this for decades. So he'll notch this up as a win, and already be working on his next plan.

I don't see an imminent escalation, unless Iran itself escalates things (in ways other than economic)

ourmandave• 1 year ago

After the strike and before this reporting Israel could justify de-escalation by saying the nuclear program was crippled...

Except Netanyahu doesn't appear to want to de-escalate. And has a long history of repeatedly declaring Iran is only X weeks away from a practical nuke to justify immediate strikes.

twixfel• 1 year ago

If the rhetoric is actually true then it’s not just rhetoric and things will escalate regardless based on the facts on the ground. If it’s not true then yes you would have a point, maybe.

pjc503• 1 year ago

I'm not sure Iran has many options for escalation left. Other than actually completing the nuke, which is something of a circular argument: they might escalate by building a nuclear weapon, but the only reason alleged for Israel escalating against them (which of course gets a free pass) is .. they're building a nuclear weapon. You can't escalate by doing something you're already doing.

It only counts as escalation if they weren't building a nuke but Israel bombing their nuke programme forced them to build a nuke?

perihelions• 1 year ago

I think it's just the one nuclear bunker-buster (B61 mod 11).

"Get To Know America’s Long Serving B61 Family Of Nuclear Bombs" (2019)

https://www.twz.com/19263/get-to-know-americas-long-serving-...

"The most recent operational variant, the B61-11, entered service in 1997 and is the first to dramatically differ in form, as well as function. The U.S. military treats this version as a combination tactical and strategic bomb even though it’s based on the B61-7 and reportedly has a single, maximum yield of approximately 340-400 kilotons."
"The bigger difference, though, is that it has a significantly reinforced shell, possibly with a depleted uranium penetrating nose section, a delay fuzing system, and a booster rocket motor in the rear, all so it can break into deeply buried, hardened facilities. There are less than 100 of these bombs in existence, according to publicly available data, and the United States more or less built them with one specific target in mind."
"In 1996, Russia finished work on its Kosvinsky Kamen bunker, part its so-called “continuity of government” plans to protect senior leadership in the event of a nuclear strike or other major emergency. Similar in concept and reportedly similarly—if not better—protected than the U.S. military’s Cheyenne Mountain Complex or Site R, also known Raven Rock, the Kremlin built it specifically to be hardened against nuclear weapons going off up above. The B61-11’s job was to put even those defenses beyond reach in what would likely already be an apocalyptic scenario."
"Before the B61-11, the United States planned to use a much less elegant approach when it came to nuclear bunker busting, relying on aging B53 bombs, a design dating back to 1958 for this purpose. These 12-foot long, 4-foot wide, nearly 9,000 pound weapons would have used the sheer explosive power of their 9 megaton yield to create massive craters and crush underground targets. The U.S. government also explored using a modified B83-1, with its 1.2 megaton yield, for the role before deciding on the modified B61."

(The article also discusses the newer B61-12 as a potential substitute, although it's unclear as the key information is secret).

aosixnskak• 1 year ago

Escalation is inevitable. Israel wants regime change. The US (Trump) simply wants Irans nukes gone. Israel has outsized influence in US policy and has shown they’re willing to escalate if things look like they may deescalate - this whole thing started because Israel decided to attack during negotiations.

The only way this deescalates is if the US is able to regain some sovereignty and remove the parasitic influences dragging us to war. From Trumps cabinet to the broader administration, military industrial complex, media and even many prominent billionaires like Adelson - there’s too many Zionists pulling the strings.

mjburgess2• 1 year ago

It's important to add that it isn't just concrete -- but the relevant installation was under ~100m of granite.

TheAlchemist2• 1 year ago

I'm actually wondering why it's "only" buried under ~100m (which is already on the higher end of the depth estimates).

Why not pick a mountain where you install the bunker 300m under the peak ?

The way I understand it, is that they drill horizontally, so it doesn't really matter how high the mountain is, but it does matter how high it is for protection obviously.

gadilif• 1 year ago

The specific composition of this specific mountain range in Fordow made it almost ideal for this purpose. It's not only the depth, but also the rock type, the fact that the rock layers were compressed, and overall accessibility - all of these limit the selection space for 'deep holes in the ground for building a nuclear facility'. Also, you need to take into account an important fact: It is in Iran... There may be other, better locations on Earth, but having sovereignty on the land is key:)

Arnt• 1 year ago

Well, what they choose to dig was deep enough, wasn't it? And that's really what matters.

mjburgess2• 1 year ago

The mountain itself is ~80m to base, and the 20m comes from assuming that trucks are just driving down into it (so a gradient down to -20m on the road). If you had deeper, you'd need to then have more complex transport mechanisms underneath the mountain.

The assumption is that they haven't done that -- but it's not implausible to add some multiple of 10m on to the estimate.

I'd imagine they studied bunker buster arms in the design, and very probably concluded, that there wasn't much need to go very deep. Demolishing 80m of granite alone is a nuclear-sized problem, +20m and maybe 10m of specialised concrete, i'd imagine is fine.

It's also highly likely that the design of the installation is robust against collapse, eg., designed so that small areas can collapse independently. So even with arms which could penetrate that deep, you'd need a large number.

I think it's plausible that the entire supply of bunker busters the US currently has could do the job, but I highly doubt the US would risk depleting its capacity on a "maybe" of this kind.

The whole operation was a performance to try a carrot rather than stick approach with israel

Hilift• 1 year ago

There were also a caravan of trucks removing large amounts of items before the raid. There are estimates Iran has 600 kg of enriched uranium. One kg of uranium is about the size as a kg of gold, or the size of a phone. So they probably removed some of the harder to replace equipment. Could have been anything. Servers, weapons and ammunition, etc.

Centrifuge manufacturing has come a long way in the previous 20 years. Precision machining has newer models with up to 200,000 rpm. "Centrus (formerly USEC) plans a centrifuge with 60 cm diameter, 12 m height and 900 m/s peripheral speed." Even with their centrifuge manufacturing facilities hit/destroyed, they could reconstitute within a year or two and continue the refinement process.

https://en.wikipedia.org/wiki/Zippe-type_centrifuge

andrewinardeer• 1 year ago

200,000 revolutions per minute?

Boggles the mind that this is 3,333 revolutions per second.

I'm not saying you're wrong but a quick check of a few LLMs says that 90,000 RPM is widely cited as the practical upper limit for current operational centrifuges in facilities like those operated by Urenco, Rosatom, or Orano.

900m/s is approx Mach 1.5.

rurban• 1 year ago

Important to add that they targeted the ventilation shafts. So 100m of air, not granite.

bell-cot3• 1 year ago

I'd assume the Iranians have seen Star Wars - and know not to build convenient shafts that go straight down to the stuff which their enemies want to destroy.

dinfinity2• 1 year ago

You can damage the entrances, take out the aerials, and cut off communication to a command bunker with hits in the right places. In military terms, it might as well be a crater, even if the occupants are unharmed.

This seems like nonsense. Rebuilding an entire facility from a crater is so much work that you may just as well build it elsewhere.

Fixing entrances and aerials seems trivial in comparison.

Hypersonics are missiles which travel through the atmosphere at speeds in excess of Mach 5. Equipped with tungsten penetrators, they could act as “rods from God,” punching through layered concrete like an armor-piercing bullet. With no explosive warhead, such weapons do damage through kinetic energy alone.

Then what, though? Underground installations are not like bodies; you can't just expect to take one out by shooting through the brain, heart or lungs (which is hard enough to do as it is). Unless you're launching 100 non-explosive hypersonic missiles, you're probably not going to do much damage.

Maybe the hypersonic missile can be used to create a path for a normal warhead to penetrate to where the explosive can do the required amount of damage. That's going to require some pretty precise needle-threading, though.

Alternatively, the hypersonic missiles could have a core of extremely radioactive material.

n1b0m• 1 year ago

Given the extremely vibration sensitive nature of centrifuges, significant damage may still have been caused without the bombs penetrating the concrete. Although based on the latest report from the Pentagon it may only have set program back by months.

candlemas• 1 year ago

How do they deal with earthquakes?

concerned_user• 1 year ago

They are only sensitive to vibration while running, if turned off then just checks and re-calibration needed before turning them on again.

mkl95• 1 year ago

The Iranian state is playing the long game by letting Israel and the US celebrate their victories while they carry on with their plans. They will let the big boys bust a few rocks here and there if that's what it takes.

seunosewa• 1 year ago

They lost their top military leaders. They can't possibly be happy.

627467• 1 year ago

They aren't but does it matter? iranian regime (similar to CCP) prioritize long term goals and regime survival - which makes sense if you actually have long term goals - while we count short term victories and wait for next election cycle and netflix/apple release.

Israel (and SA) are the only ones with skin in this game and won't be able to easily interfere forever. yes, iran has been massively infiltrated - kudos israel. But after all this recent spectacle, the regime will be focus on survival - this includes cleaning house and continue bomb building efforts.

Akasazh2• 1 year ago

Maybe a culling improves the quality of the crop?

Napoleon proved that having meritocracy in the battlefield leadership beats out old sullen generals that are there because they have always been..

Havoc• 1 year ago

Been saying that since before the bombing.

You can inherently dig deeper than you can bomb. Mines go miles down. The odds are not in your favour unless you know it’s shallow and soft - and administration is giving more yolo vibes than knowing vibes

nickdothutton• 1 year ago

Everything is signalling.

ChrisArchitect• 1 year ago

Early US Intel assessment suggests strikes on Iran did not destroy nuclear sites

https://news.ycombinator.com/item?id=44369735

vorpalhex3• 1 year ago

This headline has been circulating but it's "technically correct but entirely wrong".

You don't destroy a facility by bombing through concrete and exploding it. This isn't an action movie.

You overpressure the structure with a shockwave.

By targeting the vents, we've produced a 200m crater showing that the shockwave did violate the facilities containment. That place is gone.

This is the same sort of silly as "but they didn't blow up the reactors!" No, they intentionally avoided them to avoid throwing radiological material into civilian areas.

We can detect a pencil size rod of uranium from satellite and plane - because we've informed countries when they have had radiological leaks. If Iran moved any meaningful material (doubtful, uranium is hard to transport when enriched..) then the US knows where.

adrianN2• 1 year ago

Can we detect uranium when it is transported in shielded containers?

vorpalhex3• 1 year ago

It's uranium gas (because this is part of enriching) so it has to be shielded gas containers. Those require special handling.

If they had moved a few KG it's reasonable for the containers to be heavily shielded but 400KG? Not a chance, that would be hundreds of trucks and tons of specialized equipment.

Akasazh2• 1 year ago

Ok. So it's just tactical that the commander in chief foreshadowed the bombing?

vorpalhex3• 1 year ago

1. With 40+ refueling craft in the air, everybody understood what was happening

2. The facilities are dual use. Bombing IRGC is fair game, bombing Bobby the Janitor or James the Steam Engineer is not. Giving a warning so personnel can evac is normal.

tmaly• 1 year ago

I heard mention somewhere that 40 large trucks were at the site weeks before.

Was this attack just all for show, did they move everything?

Bunker Busters probably failed to penetrate Iranian concrete

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