Taking down hardened facilities..

[numbersman]

I know there are lots of ex-military types around here, so I thought I'd post something I was thinking about the other day. What with all the speculation about Israel hitting Iran's nuclear facilities, and the thought that they might be too hard too take out using conventional weapons, how about this? Instead of dropping a single conventional hardened warhead on an underground facility, how about dropping three (or maybe even more), evenly spaced around the facility. You'd need complete air superiority, of course, but would the converging shockwaves be more damaging than direct impacts? Is there a chance that the shockwaves would reinforce each other, maybe causing such pressure that the facility would shake itself to bits?

[Gollnick]

Keep in mind here, folks, that this thread is NOT in the political discussion forum. So, discuss the technical questions with no -- repeat NO -- politics, please.

[Esav Benyamin]

Why would you be concerned with the nuclear facilities themselves at first? You realize they need air superiority. That requires taking out the Iranian military. Once that's done, the rest is much simpler.

[A.W.U.K.]

I don't know how well it would work but for converging shock waves, all the bombs would have to hit the ground - or be timed to detonate - at exactly the same time.

The original Tallboy and Grand Slam bombs of WWII were designed as "earthquake" bombs. They had very strong casings and fuses with a slight delay so as to explode deep underground. AFAIK there are no such bombs around today but, given the plans, it shouldn't take too long to manufacture some.

http://en.wikipedia.org/wiki/Tallboy_bomb

I've visited the V2 missile bunker at Eperleques and seen the damage done there by Tallboy bombs:

http://en.wikipedia.org/wiki/Blockha...3%89perlecques

Bielefeld, 14 March 1945
The No. 617 Squadron RAF Avro Lancaster of Squadron Leader CC Calder dropped the first Grand Slam bomb from 11,965 ft (3,647 m) on the Schildesche viaduct.[12] More than 100 yards of the Bielefeld viaduct collapsed through the earthquake bomb effect[13] of the Grand Slam and Tallboy bombs of No. 617 Squadron. No aircraft were lost.[14] 50 Civilians died.

http://en.wikipedia.org/wiki/Grand_Slam_%28bomb%29

[Gollnick]

The US military has ground-penetrating "bunker buster" bombs. They are very heavy and long/slim in shape designed to be dropped from high altitude so as to develop considerable kenetic energy as they fall so that they will penetrate deep into the earth when they hit. Then, a delayed fuse causes a deeply-subterainian explosion.

These bombs are very heavy and physically-large. Israel does not have a bomber aircraft that is able to carry them. It's gotta be a good, old B52.

Of course, these bombs are precision-guided using GPS. But what you can't control is how far the bomb will penetrate.

[Codger_64]

Israel has our prior generation bunker busters and they can be carried by their existing aircraft. Those bombs weigh only 5,000 pounds each.

[jdm61]

Gollnick and Codger, the current generation GBU-28 bunker buster bomb will fit on an F-15E. That was one of the aircraft that it was designed for. They weigh 5000 pounds and will penetrate 20 meters. That bomb has repaved all of the older ones, including the one that was specially designed for the B-2. The new monster 30,000 pounder is made specifically for the big boys, but it may not even be in service yet.

The US military has ground-penetrating "bunker buster" bombs. They are very heavy and long/slim in shape designed to be dropped from high altitude so as to develop considerable kenetic energy as they fall so that they will penetrate deep into the earth when they hit. Then, a delayed fuse causes a deeply-subterainian explosion.

These bombs are very heavy and physically-large. Israel does not have a bomber aircraft that is able to carry them. It's gotta be a good, old B52.

Of course, these bombs are precision-guided using GPS. But what you can't control is how far the bomb will penetrate.

[Nordic Viking]

Americans make great weapons and then the Israelis improve them - so I think the biggest hinder is not the tech but physically getting to Iran and back.

[jdm61]

The nuke facilities in Iran are about 900 miles from Israel. The problem is flying over Syria. Iraq, etc. it appears that the facilities might be in range of the sub launched Popeye Turbo cruise missiles the Israelis have on their Dolphin class subs, but those are nukes. The question that hasn't been asked yet is if the Israelis can mount a heavy, precision guided conventional warhead off any of the Jericho ballistic missiles.

[Skimo]

Numbersman, for a short answer, no.

[Triton]

I've wondered about that, do you really have to destroy the bunkers to put them out of commission? How about just turning out all the power and cooling to them? Of course the other thought that occurs to me is perhaps it would be easier just to drop bombs on the guys that are directing the Iranian scientists to make the nuclear weapons, unless they have taken to living in hardened bunkers too...

[Gollnick]

...perhaps it would be easier just to drop bombs on the guys that are directing the Iranian scientists to make the nuclear weapons....

Or attach bombs to their cars maybe?

[Triton]

Or attach bombs to their cars maybe?

Indeed. I think that has already been happening hasn't it?

[jdm61]

Triton, the Iranians already know that you REALLY have to protect your power source to your centrifuge cascade. Hell, you can get that kind of info from books. Apparently there are some points when you spin them up and down where if you don't do it in a controlled fashion, they might get some nasty harmonic vibrations and tear themselves apart, filling the the entire facility with fast moving uranium hexafluoride gas and shards of carbon fiber and metal. Remember that when enriching this stuff, you essentially have to spin a tube of gas fast enough to get the slightly heavier U238 atoms to move to the outside, leaving the VERY small amount (.71-.72% of the total mass) of U235 in the center. From what I have read, the slowest part is getting it from .71% to the 3% U235 "yellowcake" that you need for reactor fuel. I'm not sure how much their assholes puckered up when some of the computer systems at their enrichment plant got hacked, but that was probably a tense moment. What could get interesting is the new 10,000 pound penetrator that we are working on. Same size as the old Tall Boy, so it may have enough explosive to cause the "earthquake effect" The 30,000 pound Big BLU MOP has over 5000 pounds of filler, But the GBU 28 "only" has around 600 pounds. That shows you how much steel you have to use to make a bomb like that. Its like making an artillery shell. The impression that i get is that they want to 10,000 pound bomb to have that earthquake effect and also penetration closer to the 200 feet of earth that the MOP has. The MOP is pretty fat and was built so that 2 could be carried internally by a B2, so i suspect that eh new one will be skinnier like the GBU-28, which looks like it does because it was original machined out of an old M110 8 inch howitzer barrel. Another trick to increase penetration would be to trig them with a solid rocket motor.

I've wondered about that, do you really have to destroy the bunkers to put them out of commission? How about just turning out all the power and cooling to them? Of course the other thought that occurs to me is perhaps it would be easier just to drop bombs on the guys that are directing the Iranian scientists to make the nuclear weapons, unless they have taken to living in hardened bunkers too...

[timcsaw]

I think that "we" soon may find out what works and what doesn't.

[CWL]

... Of course the other thought that occurs to me is perhaps it would be easier just to drop bombs on the guys that are directing the Iranian scientists to make the nuclear weapons, unless they have taken to living in hardened bunkers too...

The Isrealis attacked Iranian nuclear research facilities in back in November of 2011, and managed to destroy a good portion of their efforts and delivery system (missles), they also managed to kill the military head of the nuclear weapons program. This has set the Iranian efforts back quite a while.

This wasn't admitted by Iran for obvious reasons.

First published as a mysterios explosion that destroyed an Iranian base.
http://www.nytimes.com/2011/11/30/wo...tary-base.html

More came out after Wikileaks disclosed information about Isreali commandos working with Kurds s behind the attack.
http://www.ynetnews.com/articles/0,7...195342,00.html

[diamdave]

Someone above posted GBU-28 will penetrate 20 meters. If I'm not mistaken, I believe I read the facilities are 300 feet below surface.

[Esav Benyamin]

Their entrances are at the surface.

[jdm61]

If the bomb is big enough, you don't have to penetrate the roof. That is why we are messing around with a new bomb that is big enough to get deep and has enohg explosive to create that big underground cavity like the old Tall Boy and Blockbuster and the new MUP do. These problems are not new. We have had to think about them for a while in Gulf War 1 and when thinking about how we would deal with the hardened sites in North Korea if the feces ever hit the rotary ventilating device over there. Recent news indicates that we may have to start thinking about the nuclear version of this once again as it relates to the Chinese.

Someone above posted GBU-28 will penetrate 20 meters. If I'm not mistaken, I believe I read the facilities are 300 feet below surface.

[Gollnick]

The ideal explosion happens, of course, inside of the underground facility itself. But that is difficult to achieve. An explosion above the facility will hopefully collapse part of the roof of the facility. An explosion below it will hopefully collapse part of the floor. Even if you can make just a small rupture of either the roof or the floor, you can do two important things, first, allow in a lot of ground water. And second, create doubt about the structural integrity of the remaining facility such that it has to be abandoned. Underground facilities have a lot of difficulties: ventilation, ingress of ground water, supply of utilities, removal of wastes in all forms, access to the surface, etc. If you can disrupt the solutions to those problems, you can render the facility unusable. Such disruptions are best accomplished by an explosion above the roof of the facility.