things that make you go boom

Downblog there’s been some discussion of whether the muppets of the apocalypse were trying to make a thermobaric bomb the other day. That reminded me of Thomas Ricks’ account of second Fallujah in Fiasco, where the Marines apparently improvised a combination of C4 and propane gas cylinders as a house and bunker clearing device (for that “instant flatpack” effect). Fallujah also saw the use of more conventional thermobaric weaponry for the first time by US forces.

From al-Qaeda’s side of the hill, thermobarics weren’t new. The Russians deployed them indiscriminately in Chechnya. What they lacked was a means of fabricating their own, until, perhaps, US forces in Fallujah brought the devices low enough down the technology curve to make amateur experimentation viable. Certainly, Iraqi al Qaeda seems to have been dicking about with gas bombs since then. The apparent involvement of Iraqi national Bilal Abdulla in the events of last weekend maybe brings the connection home.

Such is technology transfer between enemies. According to Buda’s Wagon, the origins of the ANFO car bomb lie with the Wisconsin Department of Fish and Game, who produced a pamphlet explaining how a mixture of fertiliser and fuel oil would be a handy way for the rural resident to excavate his own fishing hole. This advice was taken up by Weather Underground radicals, who used it to bomb a military facility at the Madison faculty of the University of Wisconsin in 1970.

From there the technique was picked up by the IRA, at first with poor results: an IRA quartermaster was killed while trying to mix fuel oil and ammonium nitrate with a shovel in his shed. So PIRA decided to get rid of the remaining stuff by putting it all in a car and detonating it, and the ANFO car bomb was born.

Prior to the discovery of ANFO, the car bomber’s activities were circumscribed by the need to steal or buy commercial or military explosives. Post-ANFO, the bomber could just go to the local garden centre. One imagines that this loophole has been pretty firmly shut by now in the UK: I wonder how many allotment holders have been left quaking in their wellies after being instructed by gentlemen in unmarked cars never, under any circumstances, to repeat any details of the interesting conversation they have just had to anyone.

Perhaps some awareness of this possibility was one of the factors making home grown fuel-air bombs appealing: it may have been an instinctive adaptive response to the general security climate. Yet thermobarics need a significant explosive element to work. An improvised detonator won’t do, which puts would be car bombers back in the pre-ANFO environment of needing access to ready made explosives. The hope here is that the bombers may have been ushered up a cul de sac.

Comments

[Alex]

The question was solved quite neatly in Northern Ireland by requiring the sale of nitrate fertiliser in granules of an inconvenient size for use in explosives.

BTW, I disbelieve in the "Wisconsin Fish & Game" tale - apart from the necessary Mike Davis Adjustment, the chemistry is quite obvious, and people have been making ammonium nitrate go bang for a long time. Another mixer is sugar.

[dan]

The thing to note about all the various Iraqi bombs is that the key components are still the high-explosive mortar/artillery/tank shells and/or mines of various descriptions that form the basis of their devices - the addition of fuel/gas cylinders just adds a secondary incendiary/bulk-out component to the explosive effect.

There's the same consideration with the use of chlorine gas cylinders, which adds a secondary toxic effect to the mix, and, given the particular history of Iraqi use of chemical weapons in the 1980's, no doubt adds an additional psychological component to proceedings.

The cul-de-sac that you describe is essentially a mis-match between intentions and capacities. The obvious "remedy" for this, from the Jihadi standpoint, is to work within their limitations.

As things presently stand, a Chelsea tractor aimed at a bus-queue would deliver a higher casualty count, would be impossible to defend against, and is endlessly repeatable; from a "strategy of tension" point of view it would be the perfect wedge device.

[jamie]

Yes, but it's not "terroristic" enough. It's too much like a regular RTA.

[dsquared]

I still think my Eurostar hijacking idea has legs.

[Alex]

Just stick with the TATP. It works, apparently.

Or else, what about individual assassination?

[jamie]

If you actually have a viable shipment connection from Iraq, import some of that RDX that went missing from al Qaaqaa: instant political crisis.

[londamium]

After 4 years it would seem that the shipment connection is non-existent.

Not surprising really, as I've yet to see any evidence that Jihadis in the UK have got around to procuring firearms, which are, after all, actually available.

[CKR]

My father tried to make a thermobaric bomb against gophers at one time. They lurk in caves like Osama bin Laden, but this was a decade or more ago, so my father was anticipating both the technology and the problem.

He poured a few deciliters of gasoline into the gopherhole after some excavation to find the hole, waited a minute or so, and threw a match in.

It was a big enough bang that he never did that again.

Seriously, in the proper proportions with air, gasoline is a really good explosive.

[jamie]

Jesus, Cheryl, that's immense. I now pronounce your dad officially incredibly cool.

[Alex]

This is one of the things I must get round to blogging - The Register, aside from being essentially tabloid, is being quite wildly over keen to dish the bombers' capabilities.

"They forgot the oxidiser". Umm, no. It's called air.

[Chris Williams]

? I thought that the Reg pointed out that while air is an oxidiser, it's a lousy one -making a FAE E is hard. Perhaps the point could have been made more clearly.

Here's a thought: Chapati flour . . .

[dsquared]

The Register has a lot of form in this direction - they were quite silly about trying to pretend there was no danger from liquid explosives on planes too IIRC. They actually missed a trick on this one, as if I'd been writing that story, I'd have mentioned that the propane cylinders you can buy from B&Q have special safety valves that are meant to prevent the kind of pressure-buildup explosion they were talking about.

Londamium makes a good point, but I'm not sure I'd be too calm - Jermaine Lindsay was a career criminal and if future al-Qaedas are also drawn from prison converts, I'd guess that if they want firearms they'll get them.

Meanwhile, the entire sane world is apparently bowing down to Hasan Butt for his incredible insights into what makes young British Muslims go terrorisss, despite the fact that these guys were neither young nor British. Obviously only a liberal dupe would believe that an attack carried out by a refugee from the Iraq War had anything to do with the Iraq War, sheesh.

[Alex]

Yes, we're getting quite a little industry of professional ex-jihadis together..

[ajay]

Few match the fervour of a converted sinner or a fallen saint, Alex. Well known fact. Look at St Paul and Christopher Hitchens.

[ajay]

The Register has a lot of form in this direction - they were quite silly about trying to pretend there was no danger from liquid explosives on planes too IIRC

They spent a long time explaining that manufacturing liquid explosives in an aircraft toilet was silly and impractical, and rather ignored the fact that no one had suggested the terrorists were planning that in the first place.

[jamie]

There's probably a great book to be written about chancers of the WOT, maybe alomng the lines of Maurer's The Big Con: you could run the gamut from Hitchens to Ali and back, maybe including Gorgeious George for balance. As a kind of mijnor thread you could have Nick Cohen wandering through the whole galere, making conficent predictions which promptly blow up in his face.

[David Gillies]

You still need a booster to get a high order detonation out of ANFO. You get a bigger bang for your buck with ANFO, but there's still a need to acquire some 'real' high explosive like PETN or PE4 first. Detcord on its own won't trigger ANFO.

[Phil]

Jermaine Lindsay was a career criminal

Missed that (and it's rather relevant to some research I'm planning*). Have any of our other convicted jihadi types had form as ordinary decent criminals?

*No, really.

[dsquared]

Well, Reid the shoebomber was, but I can't think of any others.

[jamie]

Weren't some of the 21 July bombers part of a gang?

[Alex]

Back on-topic, details published today bear out Chris Williams' suggestion above. The 21st July Guys' bombs consisted of an initiator of pure TATP, which was meant to disperse and ignite a mass of flour and peroxide, the blonde juice acting as an extra oxidiser. They failed, it seems, because they didn't use enough TATP in the initiator stage.

[dsquared]

To be honest I'm very sceptical of all the published information about 21/7 because it relies on us accepting the proposition that the 21/7 bombers were completely unconnected to the 7/7 ones and just happened to have more or less the same idea (also the idea of buying 400 gallons of hair dye and reducing it down to propellant strength by boiling it on a stove sounds screwy to me)[1]. I don't understand why we're getting all these very specific details of how the bombs were made this time, and nothing at all about the 7/7 ones. I'm guessing that, as is often the case, there's a bit of disinformation being put into the system here, probably for completely laudable reasons to protect our double agent or some such.

[1] all the references on the net to boilding hydrogen peroxide are on taxidermy websites for dealing with deer skulls, who knew.

[Alex]

You're now stretchin' a bit; this is evidence in a trial, a bit different to "sources close to.."

Also, D2, gallons are not the same as litres.

[dsquared]

[this is evidence in a trial]

Yeah, but not direct evidence of them actually doing it; it comes from the forensic service who reverse-engineered the bombs, and who appear to have set up quite a different detonation system (ie, a proper fuel-air explosion) for their "Brainiac: Science Abuse" demonstration. I don't believe that you can distill hydrogen peroxide from 18% to 70% by boiling it on your stove (and the world of internet nerds building homemade voltaic cells appears to agree), so I think that they must have concentrated their peroxide some other way which we're not hearing about, and would additionally surmise that whoever refined their peroxide for them also gave them the TATP.

I am not keen on getting into conspiracy theories, and to be honest I am unlikely to kick up a hell of a civil liberties stink if controls are put on the sale of H202, but I'm taking a rather guarded view of what's coming out of this trial. In particular, I'm getting slightly irritated by the constant repetition of the line that "if the bombs had detonated, they would have caused more deaths than 7/7". As Jarndyce pointed out at the time, this isn't consistent with the realities of public transport.

[Alex]

May I point out that distillation is not actually the most difficult process to achieve, even with commonly available goods? If you can catch the vapour coming off whatever it is you're heating, you're distilling.

Various useful techniques and equipment are widely available for other (rather un-Islamic) applications, even though these are illegal.

[dsquared]

[If you can catch the vapour coming off whatever it is you're heating, you're distilling]

but H2O2 boils at a higher temperature than water; the vapour is the bit that you want to get rid of. So what we're talking here is something like reducing a stock - the idea was that they literally had a pot of peroxide on the stove (better get a big saucepan if you're planning on boiling 440 litres of the stuff) and you boil it up like jam then come back when it's concentrated enough. It is a wildly mad-headed idea - at least they weren't using a gas hob but nobody I could find on the internet regarded this method as anything other than a good way of creating an industrial accident - there's bound to be a load of H2O2 vapour hanging round your kitchen along with the steam, and that really is something you don't want in your kitchen. Plus, like jam, you don't want to boil it too long, because if you get the concentration up too high at a temperature above 70C, it's likely to blevey (not like jam).

The internerds making voltaic cells all reckoned that boiling wasn't even a joke, and that the correct way for an amateur to go about concentrating peroxide was either a vacuum pump or sparging (and my new favourite word of the day is "sparging").

So it's a Bayesian calculation; either these guys, who appeared to be very stupid indeed in most other respects, were colossally lucky enough to purify 440 litres of hairdresser's peroxide by boiling it on a stove without killing themselves, or they actually got the peroxide another way and somebody introduced a white lie into the evidence. I think that route 1) is unlikely enough to make route 2) the currently favourite choice pending more evidence or someone unearthing a combination of google terms that lead to even one single person managing to purify H2O2 by boiling it. Yes, thank you, I have recently awarded myself the post of Armchair Forensic Scientist.

[dsquared]

oh yeh, and a stainless steel or aluminium saucepan does not look to me to be a good bet for a cooking vessel for a powerful oxidant. I would have shelled out for the Le Creuset or Pyrex pans (and made sure to scrub them well, as impurities of any sort, including those which are always present in hairdresser's peroxide, are apparently capable of providing quite a few nasty surprises when the whole thing is bubbling away merrily).

[jamie]

Regarding the 7/7 bombers, it may be that they did stumble on some novel, easily replicable way to fabricate homemade explosives that the security people don't want getting out there.

[Alex]

I should point out that George "Dick Destiny" Smith likes silently deleting comments that disagree with him. I know 'cos I left one on one of his peroxide-related posts pointing out that, no, they weren't using "drugstore peroxide" but had gone to the trouble of finding a rather more premier cru variety.

It is a wildly mad-headed idea

These people were planning to use the stuff ...to kill random tube users..by blowing themselves up...in a bid to please their nonexistent sky daddy! In the hope he would respond by converting the UK into a Wahhabi Caliphate! What makes you think they aren't wildly mad-headed?

[Alex]

Oh yes, and my first forensigoogle is a direct hit. I think they didn't use the stove...they used the freezer.

Read this..if you dare.

[Chris Williams]

Not applejack but crackerjack?

[Alex]

Totally. D2's mistake was talking to some bunch of nerds fiddling with voltaic cells. He needed maniacs playing with a) rockets and b) illegal booze.

You see the benefits of growing up in the country?

[dsquared]

yes, I got that one - it's where I learned the word "sparging". But the majority of other references seem to reckon that you need to combine freezing with sparging if you're going to get anywhere - the 18% solution has a freezing point near -10 degrees which leaves very little room for manouvre and means you're going to get tiny yields, so you need some way of getting it up to about 30% concentration before you can use the fractional freezing method to take it up to 60-70%.

Also I know from *substantial* experience with C2H5OH that a domestic freezer is an *unbelievably* inefficient way of freeze-distilling anything (furthermore, probably need to get some serious ice cube trays as they have 440 litres of this stuff to get through, which isn't as much as 440 gallons but is still quite a lot of freezing). I am just not seeing the kind of capacity for painstaking scientific work that would be needed in these guys - I am sure they would have loved to do it, but in general the combination of mad-headed Somalis and inorganic chemistry does not result in 70% pure hydrogen peroxide.

In any case, how do you store the 70% pure stuff? If you mixed it with chapati flour, why wouldn't it just start oxidizing the flour in pretty short order? Flour has quite a lot of water in it. This becomes quite a big issue if you're using a slow method like fractional crystalisation, as the stuff degrades pretty quickly.

[dsquared]

PS: I did grow up in the country dammit. If freeze distilling was anything other than a frustrating waste of time I probably wouldn't be here. Thinking about it I've also played around with H2O2 and sugar plus catalyst, I seem to remember.

[jamie]

You lot are going to get me arrested.

[dsquared]

I have now bought a bottle of 3% peroxide, and I am typing this in the kitchen, looking at my freezer and thinking "how difficult could it be?", "she wouldn't find out, would she?" and "It would only be a little bang, I could show off to the boy". I wish I'd never met you lot.

[jamie]

Well, OK, but I want a proper solidarity campaign.

[Chris Williams]

We'll get you out. Eventually.

If you want anything looking up, I've got a copy of the Anarchist's Cookbook knocking about somewhere, but I understand that it's mainly useful if you are tired of having thumbs.

What with the applicability of the craft skills of applejacking, sparging, and distilling, I'm coming to appreciate the benefits of being under attack from teetotallers with limited homebrew experience.

[Alex]

Yeah, well, you'll laugh on the other side of your face when they invent a vindaloo bomb.

[Dan Hardie]

This thread has got to be the best disinformation campaign MI5 have ever run. How many jihadis have already been scraped off their kitchen floors, as their comrades mutter furiously 'I told Omar he should have waited for Dsquared to get back to Alex about sparging...'

[Alex]

I'm more worried about why D^2 hasn't got back to me yet after buying a bottle of H2O2..

[dsquared]

After close to 25 man hours I can confirm that there is zero, zilch, nish, nada useful information on the internet about purifying hydrogen peroxide, above the level of "evaporate it, or maybe freeze it or something". It appears that the chemistry/rocketry blogosphere are really quite responsible about that sort of thing. I naturally take this as evidence that MI5 have censored the internet.

[Alex]

So; you couldn't freeze it?

[dsquared]

It froze into a solid block in my freezer. To be honest I didn't take much trouble over checking it to sweep out ice crystals though, and I only had the 3% solution rather than the 18% so I don't conclude much either way from this.

[Dan Hardie]

And when the missus found the strange object in the freezer, your excuse was...?

[dsquared]

she didn't, and if you meddling kids can keep quiet she won't. To be honest I would probably get away with it; we did build a compressed air spudgun together once and that was pretty damned cool.