The Liquid Bomb

We finally have some actual information about the “liquid bomb” that was planned by that London group arrested in 2006:

The court heard the bombers intended to use hydrogen peroxide and mix it with a product called Tang, used in soft drinks, to turn it into an explosive.

They intended to carry it on board disguised as 500ml bottles of Oasis or Lucozade by using food dye to recreate the drinks’ distinctive colour.

The detonator would have been disguised as AA 1.5 batteries. The contents of the batteries would have been removed and an electric element such as a lightbulb or wiring would have been inserted.

A disposable camera would have provided a power source.

Any chemists want to take a crack at this one?

Posted on April 3, 2008 at 5:11 PM145 Comments


jeffd April 3, 2008 5:24 PM

Given what we know about airport security and hydrogen peroxide, is there any way that they wouldn’t be able to smuggle this on as contact lens solution?

Bruce Schneier April 3, 2008 5:27 PM

“Given what we know about airport security and hydrogen peroxide, is there any way that they wouldn’t be able to smuggle this on as contact lens solution?”

Of course not. I routinely take a 12-ounce opaque bottle of contact lens solution through airport security. The bottle could be filled with anything. No one notices. No one checks. No one cares.

Anyone who thinks the liquid ban is anything other than security theater is just not paying attention.

James April 3, 2008 5:28 PM

PhD chemist here, with some experience in explosive chemistry, though not commercial explosives.

However, there is really only one reliable way to get devastating explosive power required to take an airplane out of the sky: you need to detonate a mixture in which there is a way to convert liquid or solid components into gases very rapidly.

So, you need something like trinitrotoluene and a detonator, where the chemical stability of the compound is low enough that it will rapidly decompose into, typically, nitrogen gas and carbon dioxide, or equivalent gases, and at such a speed and with enough energy that it expands rapidly enough to destroy its surroundings.

Note that this must be a CHEMICAL decomposition. Something that boils and ruptures a container will not have enough energy.

Petréa Mitchell April 3, 2008 5:30 PM

Forget the scientific merits of the case– as soon as the story gets condensed to “they were going to blow up a plane with Tang”, the late-night comedians are going to be all over this one.

For those of you who insist on examining the scientific merits, here’s a page purporting to list the contents of Tang:

James April 3, 2008 5:46 PM


The problem here is that although the latent energy is there, it requires a fairly large amount of catalyst to decompose it explosively. Hydrogen peroxide is simply not a good enough oxidant to produce a devastating explosion except in highly controlled experiments. You need to have the oxygen right there in high concentration, either as liquid oxygen (you wouldn’t be able to get that on a plane) or as part of the explosive itself.

Fred P April 3, 2008 6:01 PM


Would it be possible to use the Oxygen from the drop-down masks that come down in the event of low air pressure? I’d assume (perhaps incorrectly) that they’re connected to a relatively large, concentrated Oxygen supply, and I strongly suspect that someone could either force the compartment open or cause the system to falsely fire off, or possibly hack directly into the oxygen source.

eddie April 3, 2008 6:02 PM

all I can say is that for my lenses cleaning, I use a hydrogen-peroxid solution at 3%.

Can it be concentrated?

Ian Woollard April 3, 2008 6:06 PM

Simply carrying enough Tang to make this work is probably in and of itself suspicious. Nobody likes Tang that much!

I suspect somebody has been drinking the cool-aid- rather than mixing it with HTP to test it out. 😉

Conor April 3, 2008 6:13 PM

@Fred P:

The oxygen supply for the drop-down masks is not usually from a bottled supply. AFAIK the crew’s supply is usually from a bottled system but the passengers get chemical oxygen generators.

Nicholas weaver April 3, 2008 6:14 PM

As far as I know (speaking from gross ignorance here), sugar + oxydizer can really burn well.

But to make it EXPLODE, you’d want a pressure vessel (a pipe bomb), to build up a lot of pressure. Otherwise you could get an impressive fire but which would probably be not enough to crash the plane, since any fire beyond that could easily be fought by depressurizing the cabin.

Max April 3, 2008 6:21 PM

Organic peroxides can be highly explosive and highly unstable, so it’s conceivable that given a sufficient concentration of peroxide, they could create a high explosive. Compounds like diethyl ether will slowly form organic peroxides in the presence of moisture, which is why laboratories that use it as a solvent are careful to put an expiration date on the container.

My guess is the Tang bit was thrown in either to expose the incompetence of the bombers, or to hinder random crazies. No “real” bombmaker would be fooled, however.

John Ridley April 3, 2008 6:31 PM

Concentrated hydrogen peroxide is quite hazardous. The Germans used it as one half of a rocket fuel for their experimental rocket planes. 90% hydrogen peroxide is what rocket belts run on:

History channel interviewed one of the old German officers about it; quoting: “You put your finger in, you pull back a bone.”

Jason April 3, 2008 6:33 PM

I believe there was a case of a mysterious sinking of a early submarine (Russian?) which was eventually assumed to have been caused by a peroxide leak on a torpedo.

It may be that this group was inspired by this story. However, in the case of the submarine, what ultimately sunk the sub was detonation of the warheads triggered by the heat of the fire fueled by the peroxide, not the peroxide fire itself.

scotty April 3, 2008 6:35 PM

This is just going to make the liquid ban seem all the more foolish. As someone has previously commented, you can probably expect a few cracks from Leno tonight.

Petréa Mitchell April 3, 2008 6:41 PM


Various submarine-building powers experimented with hydrogen peroxide fuel for torpedoes, and everyone but the Russians abandoned it early on.

But the submarine accident you’re probably half-remembering wasn’t “early”; it was the Kursk. (Where the problem was indeed as you described it.)

bj April 3, 2008 6:43 PM

Can’t we just ban Tang and be done with it? Perhaps even per^H^H^Hprosecute those using, selling, and making it?

Pierce Wetter April 3, 2008 6:48 PM

It’s interesting on the TSA blog that they gave us two tidbits:

  1. It took the “experts” 4 days to replicate something dangerous.
  2. One of the keys of the new regulations is that the bottles are plastic, which rules out sulfuric acid, nitric acid, all those fun things.

I think that basically, the terrorists were idiots and going to fail. But the TSA reacted by clamping down on something that would work but that the terrorists didn’t know about. That makes more sense I think.

Also realize that even if the effect would be ludicrously small, it still might panic people to have terrorists burning off their eyebrows in the bathroom.

brian April 3, 2008 6:48 PM

tcliu … also, 50 C is not 158 F. Either they meant 70 C or 122 F

50 * 1.8 + 32 = 122
70 * 1.8 + 32 = 158

I modified the wikipedia page to reflect 122 F (which seems oddly low… maybe they really meant 70 C).

Alice McGregor April 3, 2008 7:27 PM

@Pierce Wetter:

Though, with the correct plastic, it doesn’t rule out hydrofluoric acid which can -only- be held in plastic or ceramic containers specially built for it. In fact, I used that for my entry to the last Movie Plot contest! ;^)

Justin Waxman April 3, 2008 7:29 PM

@Pierce Wetter

“which rules out sulfuric acid, nitric acid, all those fun things.”

No, not really. If you can’t figure out how to get those acids on an airplane, you’re not really trying.

Glaa bottles are more likely to be prohibited because they can be broken, yielding sharp edges, and it’s the sharp edges that are forbidden.

WackyWiki April 3, 2008 7:32 PM

Thank you brian. It’s that sort of authoritative fact checking that makes wikipedia what it is today.

Nick Lancaster April 3, 2008 7:33 PM

What gets me is the oddity of the suspects planning on using hydrogen peroxide and Tang (though I’m leery about that since initial stories involved ‘a popular sports drink’) … but there’s nothing to indicate tests, even small scale ones.

You’d think that if you planned on blowing up something using a chemical explosive in far-from-optimal conditions, that you’d have done some kind of test.

Seth April 3, 2008 8:05 PM

I’m no chemist but I used to be a demo guy in the Army and 2 cups of the stuff seems like a very small amount to take down such a large aircraft.

We used to use 2 M112s to blow a good size door down an that’s almost 3 pounds of C4. I just can’t see 2 cups of some science experiment taking a plane out of the sky.

I think the most dangerous terrorists are much smarter than people give them credit for. Their likely to use a much simpler method to wreak havoc like just taking the plane and crashing it or buy a plane of their own.

They actually have the money to buy a fleet of jets to just crash them into things we care about. Why screw around with a Mr. Wizard experiment?

Stuart Young April 3, 2008 8:31 PM


Of course, if this actually could produce a small explosion, could they not use that to blow the lock on the cabin door and then take over the cockpit? Something that produces a small explosion in this situation would make a lot more sense then.

Anonymous April 3, 2008 9:13 PM

I smell an upcoming episode of “MythBusters”.

No, wait. It’s just my pop-tart burning.

Erik V. Olson April 3, 2008 9:55 PM

Hydrogen peroxide + Hexamethylenetetramine +citric acid makes HMTD

Good. Now make it in the lav of an airplane, which is what is being posited here. Maybe high grade peroxide and sugar will make a decent explosive.

1) You’re carrying high grade peroxide how? In a water bottle?

2) You’re mixing it where?

saint ignorantius April 3, 2008 10:05 PM

Of course you can blow a drink up with Tang; that stuff went to the moon, what can it NOT do?

WarLord April 3, 2008 10:42 PM


On the wiki entry a “BLEVE’ is an event like happens at a refinery or tankfarm…

Large tank of flammables burns, makes a vapor that then makes a BLEVE – That would posit a large quantity of liquid to gasify or more likely a gas liquified under pressure ie propane that ignited then etc etc

I don’t see a “stable” liquid at STP doing a major BLEVE event…

Enjoy the journey


Naught April 3, 2008 10:53 PM

“What the bombers intended to do was carry hydrogen peroxide mixed with Tang or other similar organic material onto the aircraft in their hand luggage disguised as 500ml bottles of Oasis or Lucozade type soft drinks. The mixture was to be detonated by some form of home made detonator. In all likelihood this was to be a chemical composition called hexamethylene triperoxide diamine (HMTD).”

The stuff was going to be pre-mixed — so no mixing of nasty chemicals in the lavatory.

wench April 3, 2008 11:12 PM

Is there any reason why high-grade peroxide couldn’t be in a water bottle? I know food grade/weed killer grade hydrogen peroxide comes in bottles.

And I believe the german guy – that stuff’s vicious, even in just food grade concentration.

CRX April 4, 2008 12:21 AM

Yes this sort of thing can work, if you get the details right. However from the article it sounds like the plotters had not done ANY testing, and so didn’t know about some of the implementation difficulties they would have faced.

High test peroxide (HTP) can be mixed with any of a wide range of fuels to form powerful explosive mixtures. In the right ratios it can be cap sensitive or even spark sensitive. A search of US patents will turn up many examples; one that I have offhand is US2452074. It describes explosive mixtures of HTP and glycerine, many of which are cap-sensitive. It also mentions that those mixtures are much LESS sensitive than those with many other fuels… including cane sugar,
the main ingredient of Tang.

Ingredients 2 and 3, fructose and citric acid, would also be suitable ingredients for the alleged explosive.

As an aside there is a VAST amount of ill-informed heresay and lore concerning HTP on the internet, written by people
who have never worked with it or even bothered to study the first-hand reports of those who have. HTP isn’t baby powder, but it’s not nearly as treacherous as people make it out to be. Consider this report from John Carmack, founder of Armadillo Aerospace. (This quote was posted as a comment in this blog back when this plot was first reported; sorry I can’t remember who to credit for posting it!)

Some people are confusing deflagration and catalytic decomposition of peroxide mixtures with detonation. The way HTP is used as rocket fuel is not comparable to its use as an explosive. Proper HTP mixes are powerful and brisant high explosives, on a par with TNT or better. Generally they are secondary explosives and will thus need a detonator, but the plotters had that covered. The article says they intended to use an HMTD detonator triggered by a light bulb filament. This is a common improvised setup, and can be quite effective. There is one slightly tricky aspect but odds are if they’d read enough to come up with that idea they’d also read enough to know how to make it work.

I don’t how big a bomb it takes to bring down a plane, but given that a roughly comparable amount of explosives brought down Korean Air flight 858 (350g C-4 plus 700ml of PLX) I can safely say I would NOT want to be on a plane with 1 liter (2x 500ml bottles) of a well-designed HTP explosive.

There are some stumbling blocks (which I’m not going to list) that the alleged plotters would have discovered in the course of testing. (If they tried to execute their plan without any testing I think their odds of success would’ve gone way down.) I don’t know if they could’ve sorted out the bugs or not, but make no mistake that in principle the plan could have worked.

John Henry April 4, 2008 12:29 AM

I can’t speak to the bomb but can add two comments from personal knowledge.

1) Contrary to the comment by Pierce Wetter, there is no reason that sulfuric or nitric acid can’t be carried in plastic (polyethylene, the most common bottle plastic) bottles. I used to use it industrially in the 70s & 80s and that is how we got it. Also in PE plastic drums. I just verified this in Google.

2) Sugar can be highly explosive. I knew of a chewing gum plant in Long Island City(?) that belonged to Warner-Lambert that was pretty much leveled by a sugar explosion in the 70’s. I am not clear whether this was just because many dusts tend to be explosive. My impression was that the sugar itself caused the dust explosion to be more severe. I could not find anything about the explosion on Google just now but did a lot of work for W-L in a Rolaids plant in the 90s. They took what I thought to be rather extreme precautions compared to other companies with similar processes. The explosion was, I was told, the reason why.

Not idea whether sugar would make a good component for a bomb.

John Henry

Infosponge April 4, 2008 2:03 AM

I’m going to put this out on the record now and state that I will be amazed if the TSA doesn’t find a reason/excuse to ban more widely used goods from aircraft between 1 September and the US election.

The liquid ban isn’t about security or even security theater. It’s about the politics of xenophobic fear.

thc April 4, 2008 2:39 AM

they planned to use hydrogen peroxide (liquid) as one component for tatp (, which is a white powder. the other component is acetone (liquid).

the bomb is not liquid at all.

tatp is only effective when it’s dry – freshly synthesized wet tatp is not usable. this means they actually had to produce and dry tatp on board of the planes (evaporating the remaining acetone).

it’s hardly imaginable going unniticed by using airplane lavatories as laboratories, filling the plane with the acrid smells of acetone and tatp.

Alistair April 4, 2008 3:17 AM

I would normally be the last person to argue that the current theatre improves security, but surely you only have to look at this discussion (and many others in the past 18months) to see that no-one really seems to know whether a combination of the right liquids could produce a dangerous explosion. So perhaps the (idea of a) ban has some sense behind it.

And of course, the argument as to whether it would have worked or not is irelevant to their trial on terrorism charges.

Alan Braggins April 4, 2008 3:37 AM

Glass bottles are more likely to be prohibited because they can be broken, yielding sharp edges, and it’s the sharp edges that are forbidden.

Except that you can still buy glass bottles in the Duty Free shop (at least you could at some airports during some parts of the War on Suspicious Liquids, and I suspect you still can in general).

duckie April 4, 2008 3:49 AM

It is silly to attempt to manufacture high order explosives from liquid components while a passenger on a commercial airline. There are much easier and less detectable ways to create a threat, explosive or otherwise. This looks to me to be an exercise in half-baked chemical engineering by the would-be perps and some really lame security theater staged by the authorities.

David Harper April 4, 2008 4:23 AM

The quoted story comes from the Daily Mail, which is not a reliable source of information, especially given its notorious antipathy to foreigners, or anyone who “looks foreign”, which includes all of the defendants.

It will be interesting to see what kind of evidence the prosecution offers for the so-called liquid explosive plot, and whether the defendants’ lawyers are smart enough to call chemistry experts to demonstrate how impractical the plot was.

Having said that, if the defendants are shown to have had the intent to blow up airliners, then perhaps a fitting punishment would be to throw them to the mercy of the passengers waiting to go through security at Heathrow. “Look, folks! These guys are the reason why you’re only allowed to carry tiny amounts of liquid in a plastic baggie!”

mushy April 4, 2008 4:32 AM

There’s a good transcript from the case in today’s guardian (, showing that the aim wasn’t manufacture of a TATP bomb in situ, rather to pre-prepare an [aqueous, from what I can glean] hydrogen peroxide / sugar mixture, and to try and make that go pop. CRX [12:21 am post] clearly has a better handle than I do on matters explosive, but I’d doubt the brisance of any such mixture.

b April 4, 2008 5:47 AM

I’m reading “A sugary drink known as Tang” in the UK media as if it requires explanation. So, is Tang even available in the UK?

sortkatt April 4, 2008 6:08 AM

About the sharp glass:
Even if there aren’t glass bottles available in the duty free anymore, there are still clock radios and other cheap electronics. Break open a clock radio, break a sizable circuit board diagonally (for the longest possible edge) and you have sharp edges aplenty.

… or steal a glass from a restaurant. Or…

Bill P. Godfrey April 4, 2008 6:13 AM

b sez… “I’m reading “A sugary drink known as Tang” in the UK media as if it requires explanation. So, is Tang even available in the UK?”

This Englander has never heard of it before today.

Auz April 4, 2008 7:30 AM

This Englandler has heard of Tang, but only from living in the states for a bit. As far as I recall, it’s basically sugar granules covered in flavoured/coloured stuff. America (or at least, New York) tended to prefer it to the dilutable liquid drinks that are more common here.

bob April 4, 2008 7:53 AM

Everyone here keeps acting as if these people FAILED. They did not. The goal of a terrorist is to trigger a government reaction which causes the quality of life in the affected country(ies) to go down; thereby decreasing stability of the existing government, and increasing the likelihood of a political change which can be in the direction the terrorist wants.

They succeeded.

syberghost April 4, 2008 8:14 AM

The other thing people are forgetting is:

A device that simply spews flaming liquid all over the inside of an airplane instead of blowing it up is still a pretty darn effective terrorist attack.

cbarreto April 4, 2008 8:15 AM

Call the Mythbusters… (Joking).

High concentration hydrogen peroxide is highly corrosive. It should be carried in enamel/glass bottles. Airport security would be aware of that.

H2O2 was used as oxidant in the first liquid rocket motors (they used the H2O steam resulting from the decomposition to power the fuel pumps). It was also used in the engine of the failed torpedo that sunk Kursk. It’s not stable neither easy to handle.

But if we go into the horror fantasy game well, the terrorists can fill notebook batteries with plastic explosive and achieve much better results.

I think people is getting weirdly paranoid these days.

Daedala April 4, 2008 8:18 AM

It’s like trying to blow up a plane with your elementary-school science project volcano.

That’s awesome.

cbarreto April 4, 2008 8:27 AM

Not to mention that late security measures (like letting pilots carry loaded guns) are posing much more danger to the security of passengers than any crazy wacko getting aboard.
Civil airplanes and firearms just don’t match.

coop April 4, 2008 8:28 AM


“High concentration hydrogen peroxide is highly corrosive. It should be carried in enamel/glass bottles. Airport security would be aware of that.”

You’re kidding, right?

yashwata April 4, 2008 8:30 AM

no-one really seems to know whether a combination of the right liquids could produce a dangerous explosion. So perhaps the (idea of a) ban has some sense behind it.

OK, if this kind of ban makes sense, then of the set of all the things that we don’t know if they can produce an explosion, which ones should we ban?

And of course, the argument as to whether it would have worked or not is irelevant to their trial on terrorism charges.

It might be ignored by the prosecutors, but it is certainly not irrelevant to the rest of us. It matters a lot whether such a scheme could succeed. Imagine we had learned that they planned to explode some Tang “made explosive” by a “magic spell”. At least that would be one less thing to worry about.

It makes a big difference whether the lunatics out there can blow up a plane, or only think they can.

The scientific consensus seems to be something like, “They might have been able to do some damage – or at least scare a few people.” Now compare that to what the TSA does every minute of every day. The people on trial might conceivably have been terrorists; but the unmistakable, professional terrorists are right in front of you in black and white at the “security” checkpoint. They are watching you, they are numerous, they are armed, and if you make one false move they can make you disappear. Now that’s terrorism.

JB April 4, 2008 9:08 AM

I’m interested in the idea that they were trying to build a smaller bomb meant to open the cockpit door. Intuitively that makes more sense to me–bringing down a plane over the Atlantic is, in a post-9/11 world, small potatoes compared to the damage one can do at the controls. If the plot was capable of creating a lock-forcing bomb, then they were indeed dangerous.

Rag April 4, 2008 9:26 AM

Now, I think we might be approaching this from the wrong angle. Of course some kind of liquid could be used to blow up a plane, but then again the same goes for gases or solids. My ham sandwich could be loaded with TNT, my wallet could be lined with uranium, my rectum could be filled with noxious gases. Or I could just be really good at hitting people in the head.

There are a million and one ways to take over an airplane. There is absolutely no chance they will ever be able to secure them all. It´s simply not going to happen. if you build a wall, eventually people will figure a way through it…or over it…or under it – it´s just a question of time.

The problem is not trying to foresee every possible threat that might be leveled at our society, but rather to resist creating conditions under which such threats might arise.

derf April 4, 2008 9:30 AM

Why go through all of this trouble?

We’ve seen in this blog before that when tested, the TSA misses 80% of guns and bombs even when they’ve been informed beforehand about the time and date of the tests.

Just go to the airport magazine shop like Sonny Bono did in Airplane 2, get the second timebomb from the right, and send it through in your carry on.

Farkshinsoup April 4, 2008 9:32 AM

I have a question: based on the verifiable information that we have to this point about the alleged “plot”, how much time would it have taken for someone to go into the lavatory and implement the explosive reaction? 30 seconds? 5 minutes? 1 hour?

Would there be a noise or other chemical reaction prior to the “explosion” that would allow people on board the plane to take notice, break in, and stop the process?

Would this explosive have to be carried back out of the lavatory into the cabin in order to do the necessary damage?

Ad April 4, 2008 9:49 AM

Frankly, even if this had been a viable plot, I would not be that impressed. What made september 11 unique and horrible is that they were able to take control of planes and use them as weapons. Heavy steel cockpit doors do more to prevent that than any of this nonsense. (Anyone remember which senator tried to push that through in the late 1990’s)

I certainy wouldn’t want to be on a plane that just blew up midair, but it isn’t quite the same scale, is it? There are many, many venues/occasions where more than a plane load of people are assembled and vulnerable that have minimal to zero security screening. Why we have chosen the airplane as the one place where we must all be 100% safe is beyond me.

Ad April 4, 2008 9:53 AM

And now that I think of it, 100% shouldn’t have appeared in the previous post. It should have read “Why we all must be 100% safe from a certain type of dramatic attack is beyond me.”

dave X April 4, 2008 9:58 AM

How is your mythical terrorist going to capitalize on a bomb as a hijacking tool anyway? They aren’t going to get the passengers and pilots to let them fly the plane into a buildings with the threat of blowing up a bomb. The best they could do is blow up the plane, and they could cause at least as much death and destruction much easier if they blew up an airline check point or other crowded space.

With an airplane hijack bomb threat, the weapon is in the effective presentation of the triggering device, not in the actuality of the explosive.

mikerus April 4, 2008 10:13 AM

The TAPT bomb wasnt even close to feasable – the synthisis of TAPT requires an ice bath as it gets EXTREMELY unstable if it reacts at too warm a temperature – as for an oxygen sugar reaction? It would burn very hot but doubtfully explode.

Don April 4, 2008 10:25 AM

Just this morning I had an 8.3ml pump spray bottle (that’s 8 – point – 3 millilitre) of oral spray confiscated at security in a regional UK airport. I’d placed it, in full view, on top of my coat while it went thru the x-ray scanner. It was confiscated because it wasn’t packed in a clear bag as per the “protocol”.
Foiled the numbskulls: I had another 2 in the pen pocket of my laptop bag.
That’s what’s so frustrating, the complete inconsistency of it all. One airline does full ID checks all the way to the gate, another doesn’t.
As for liquid bombs, bollocks, a fart after a heavily lentil laden curry might be more effective at creating an explosion.

Tom April 4, 2008 10:26 AM

“using food dye to recreate the drinks’ distinctive colour”

hydrogen peroxide is primarily a strong bleech. There’s no chance to dye it without neutralizing it.
As the beforementioned article in The Register already pointed out, the whole “liquid bomb” thing is more than fishy.

vvpete April 4, 2008 10:32 AM

I’ve seen a couple of comments here citing citric acid as an explosive component. I never heard of that before…are we sure we’re not confusing it with the notoriously unstable picric acid?

TJ April 4, 2008 10:38 AM

CRX has it right- too many people who have never worked with the stuff, “experts” in the field. I have extensive experience with “improvised” explosives, including TATP and HMTD, and would assert that- depending upon how the product were made, it would work. Both compounds are sufficiently sensitive to initiation that no high-powered detonators would be required. A Christmas tree light bulb filament is quite sufficient to initiate primary explosives- which the peroxides mentioned above most certainly are.

Everyone tends to get their panties in a wad when it comes to controlling any potential thermal runaway during synthesis, bringing out all sorts of outlandish requirements. For quick-and-dirty synthesis, it’s quite possible to chill the starting components, add the acid catalyst (only a tiny amount is required), slowly mix the components together, and produce substantial amounts of product. Some external cooling is nice, if possible, but- hey, it’s a suicide run anyway. Collect enough ice on the flight (champagne cooler from first class?), and that should be enough. This is not a hugely exothermic reaction like some would like to say it is. Coarse filtration and blot dry. Ready for use. I’d be happy to replicate the synthesis in an abandoned aircraft in an aircraft graveyard, except Sandia National Labs has already done it.

By way of qualifications, I am an explosives chemist with extensive experience in improvised explosives, including those mentioned here. I used to do contract work with the FAA Technical Center on how to keep planes from getting blown out of the sky.

However, it is worth mentioning that, although the threat is real, it’s unlikely the nitwits behind this plot could have pulled it off. The US seems to have been lucky in that those behind these plots really aren’t all that bright.

TJ April 4, 2008 10:40 AM

vvpete> Citric acid is a precursor to HMTD synthesis. Google up “citric acid” + HMTD. I wouldn’t believe any of the synthetic routes posted on the web, but it’ll give you an idea of how it’s done.

Woodwose April 4, 2008 11:25 AM

The above comments indicate that there is a wide range of opinion on the ability of the liquid bombs described to explode. The expert opinion offered includes a lot of ifs and buts that makes it seem like the potential of successful completion of the mission would have been questionable.
If the court requires example bombs to be made following the plans of the terrorists and the bombs don’t do anything other than make a bad tasting batch of Tang – what then?
Will the crime then be the intent to harm a plane by stupidity or misunderstanding chemistry?

Loren Pechtel April 4, 2008 11:32 AM

Besides, why get complex about trying to synthesize a liquid bomb on board? I just flew Wednesday and found a glaring hole in the bag-matching system. We were standing by for an earlier flight on the second leg. As it was the odds of success were effectively 100%, it wouldn’t have worked in our case, but try it on a full flight. Since it’s the second leg your bag flies anyway even if you don’t make the flight. Since it was a domestic leg after an international one we had our bags in hand while doing this. All you need is a bomb that the x-ray won’t see.

JTK April 4, 2008 11:50 AM

There’s a small community of folks who have worked on using high-concentration hydrogen peroxide (HTP) as a rocket oxidizer. HTP is essentially indistinguishable from water on visual inspection, and with a little care can be carried around in plastic bottles. I’m personally aware of one person who made significant quantities of 90+% peroxide in a home lab, and for a while carried a half-liter or so around in a polyethylene squeeze bottle to give demonstrations — he’d light a bit of paper or similar and squirt a few drops peroxide on it. I will second the comments from CRX and TJ — HTP + a small fraction of suitable hydrocarbon or organic material can be a powerful high-order explosive, and are a much more plausible threat than onboard synthesis of TATP. Still not a likely threat, but not silly.

Mike April 4, 2008 1:04 PM

If the above comments are indicative of anything, it’s that I doubt we’ll see appropriate “experts” commenting in an internet forum….besides it would be fairly hard to distinguish between someone who actually has experience vs. someone spouting total BS.

that being said, my carry on liquids were once confiscated because they were in the wrong SIZE clear plastic ziplock bag…I wanted to crap on the floor by the screening table.

ScienceGiant April 4, 2008 1:23 PM

I haven’t read all the comments, but I can take an educated guess, given my background as a science teacher.

Hydrogen perioxide at 40% molarity concentration is available at beauty supply stores (ex: Sally’s) for bleaching hair. Adding a catalyst such as sodium iodine, and you get a VERY impressive exothermic reaction. Leave the cap on the bottle so the pressure builds as solution decomposes, and yes, you could damage.

Here’s the reaction described in a pdf as “Magic Genie”

Here’s a video to watch: “Genie in a Bottle”

Dana April 4, 2008 1:27 PM

Okay, I wouldn’t call myself an explosive expert, but I have had enough chemistry and made enough pop bottle explosives to bother the neighbors (never hurt anyone and never intended to)

The thing is, h2o2 is gonna react with the citric acid and form- tada! water. Maybe you can get a higher concentrate of peroxide and you’ll make more water.

That’s gonna be the first part of the reaction. After that, you might get a high power reaction with the sugars, but more than likely its just gonna make the bottle pop- ever put drano and aluminum foil in a plastic bottle? It sounds really frightening, but doesn’t really do anything… you could wrap the bottle in fragmentary matter-nails, bb’s, but like James said, unless it’s a really high power blast, there’s not gonna be a lot of damage.

I’m not sure, but the bottle may not be able to hold a higher concentration of h2o2…. and to be honest, if I was gonna choose to do damage to a plane, the concentrated peroxide is gonna be far more effective.

bob johnson April 4, 2008 1:43 PM

Most of the responses regarding the feasibility of liquid explosives are addressing the possibility of crashing a plane by blowing a hole in it. But could someone use these materials to damage critical parts of a plane, or even to simply disorient the pilots long enough to send the plane into free-fall?

Rich April 4, 2008 1:51 PM

When I was younger and less wise I actually made HMTD for bangers and fireworks, many times, using 30 or 40 vol peroxide bought at the local chemists, hexamine tablets (camping supplies) and citric acid.

There are three major problems I can foresee:

(1) The process takes a full 24 hours because you have to wait at several stages (IIRC first time you have to wait for the stuff to come out of solution, and second time you have to wait around while it dries out).

(2) Maybe you can get this down to 8 hours, but there is one catch: This thing smells. It has a really distinctive and pungent smell which you can’t avoid. There’s no way you could sit in an airplane toilet for 8+ hours and not have everyone on the plane being extremely suspicious.

(3) It’s not reliable. Sometimes batches just wouldn’t work.

Having said all that, what matters in the court case were their intentions. If it is shown they intended to take down a plane full of passengers — whether or not their method was practical — then they deserve to go to prison for a very long time indeed.


selenized April 4, 2008 2:13 PM

At the bottom of the article in the Daily Mail it says:
“Once on board the aircraft, the improvised bombs would be hooked up to a detonator disguised as a standard AA 1.5-volt battery, containing a substance known as HMTD – produced from a mixture of household and commercial ingredients which are freely available.”

So its safe to assume they wouldn’t be making the HMTD in the plane, they would have done so before hand and packed it into batteries as a disguise. The HMTD apparently acting as a detonator for the liquid, whatever it is, which also (apparently) would have been made before hand. Assuming they had the chops to make it at home and could smuggle it past security, I’m not seeing how this would be so improbable.

wheezer April 4, 2008 2:23 PM

FYI – someone further up said that liquid oxygen is not available on planes. Air Canada at least sells it as part of their duty free shop.

Geektronica April 4, 2008 2:42 PM

I fail to see how any of these scenarios would be more serious than someone smuggling a bottle of butane and a lighter on board.

Yes, there are lots of ways to make small amounts of liquid explode with an impressive little fireball, but even an airplane bathroom has a fairly large volume of air to accommodate the explosion. It might start a fire, but I don’t think it would damage the fuselage any more than would spraying butane around and lighting it. A small fire on a plane would cause plenty of panic and chaos, but it wouldn’t take it down by any means.

The explosion, regardless of how it’s produced, would have to be directed toward the wall of the plane in such a way as to tear a hole in it. With a solid, mountable explosive like C4, that may not be hard, but with a powder? Come on. The idea of using a powder or liquid explosive to blast open the cockpit door is even more ridiculous – you’re just as likely to permanently jam it shut.

These scenarios of using liquids to create a powder in an onboard restroom synth lab are absurd. You’d do much better stuffing your underwear with M80s and matches, then stuffing them into the seams in the walls and lighting them.

Kevin McGrath April 4, 2008 2:59 PM

As most of us American boomers know Tang was supposedly invented by NASA to keep our astronauts hydrated, plus it tasted good. I remember bugging my Mom to buy this crap when I should have just stuck to natural OJ. I believe it’s even mentioned in the Tom Wolfe book “The Right Stuff” and it also may have made it to the film.

YouTube has some early Tang commericals:

jbj April 4, 2008 3:06 PM

Using a small charge to open the cockpit door? And who on the plane is going to sit by and watch some asshat try to do that, all the while battling the flight attendants? I’m in there kicking some dude’s ass LIKE NOW if that’s going down on the front of my flight. And expect bullets to come from the otherside of the door too (no they can’t tak the plane down by decompression -thank you Mythbusters).

David April 4, 2008 3:14 PM

I would really like to see someone do a detailed study of the extent to which the bozos that have been in charge of all this Security Theater since late 2001 have damaged the credibility of REAL security experts proposing REAL countermeasures and precautions.

Richard Steven Hack April 4, 2008 3:32 PM

Obviously the way to make this work is to produce something – anything – that can damage several PEOPLE and a door. You blow the door to the pilot’s cabin, throw in your bomb like a hand grenade – boom! Downed plane.

You don’t bother trying to blow the plane up – just blow the pilots up, which is a hell of a lot easier.

The REAL problem, as others have mentioned, is that you can make little explosives powerful enough to do that in so many different ways that trying to control that is effectively impossible.

Hell, a couple suicide terrorists only need to seize stuff ON the plane – a food cart, whatever – in order to force the cabin door open, then attack the pilots. No explosives needed.

Ari Heikkinen April 4, 2008 3:46 PM

Anone can make things explode (that’s not a problem), making them safe is the actual hard part.

shoobe01 April 4, 2008 3:53 PM

I think it would be trivially easy to coat the inside of a plastic bottle so it could hold decent acids for an arbitrarily long time. When I’m bored, maybe I’ll crack out some of the nitric in my basement and try it.

A few planes use O2 bottles. One per every two rows of seats, or so. The O2 generators are much more common, but recall they are pyro devices. A number of accidents with them have occurred in mines, submarines and aircraft due to their flammability. In commercial aircraft, they are behind that door above your head you can only unlock with a paperclip. I can imagine a movie plot in which the bad guy manages to fire the generator and introduce something flammable (perhaps something on the plane already) into the insulating gap to burn the thing out of the sky. Drat, too late for the movie plot contest!

JimFive April 4, 2008 4:01 PM

@bob johnson

Physically intact planes don’t go into “free fall”. If you are flying a plane, and become disoriented the best thing you can do is let go of the yoke and take your feet off of the pedals. Unless you have already taken the plane (nearly) upside down the plane will resettle itself into straight and level flight at the last trimmed altitude without your help. Note, this isn’t always true for a) aerobatic planes or b) extreme weather conditions.

Secondly, unless something is wrong, a passenger jet is on autopilot for most of the flight anyway.

So the only time this would make a lot of difference is on take off and landing.


433 April 4, 2008 4:11 PM

Well, with this new information, I heartily endorse the TSA’s liquid ban.

Everyone who has seen the fine HK movie “Bio-Zombie” knows full well that Lucozade is extremely dangerous! However, rather that a top-secret military experiment causing the undead to rise as depicted in the film, in real life it’s ready to blow planes out of the sky.

Which is more dangerous? YOU MAKE THE CALL!

CRX April 4, 2008 4:13 PM

I agree with people who’ve said that asking whether the bomb would have detonated and whether it would’ve brought down the plane is somewhat missing the point. Even a fizzle or an emergency landing of a damaged plane would still have created terror, and a plot broken up before it even left the ground still provided aid and comfort to those using an agenda of fear to gain more control.


but I’d doubt the brisance of any such mixture.

I can’t give you a hard figure for brisance or VoD, but from the limited info and tests I’ve seen I am estimating that a good mixture would be close to TNT. Not great, but not terrible either.


using food dye to recreate the drinks’ distinctive colour

hydrogen peroxide is primarily a strong bleech. There’s no chance to dye it without neutralizing it.

That was one of the problems I alluded to, but it may not be hard to solve. I just did a test. I took 3 0.5ml portions of 50% H2O2 and mixed each with with one of 3 different dyed sugar products: red cake decorator crystals (50mg), and “pixie sticks” (50mg, orange and purple). I don’t have Tang, but may get some to test. 😉 In each case the sugar dissolved peacefully, and dyed the liquid just as you’d expect. After 15 minutes there were no color changes, no evolution of gas, and no other visible reactions. 50% peroxide isn’t strong enough for what those plotters had in mind, but these results suggest 90+% can probably be dyed too.


If the above comments are indicative of anything, it’s that I doubt we’ll see appropriate “experts” commenting in an internet forum….

You’re quite right. HTP+fuel is virtually never used an an explosive so there are very few experts in that use, even less than people with hands-on experience using HTP as a propellant.

besides it would be fairly hard to distinguish between someone who actually has experience vs. someone spouting total BS.

Also true, especially since most of that experience is probably from the, ahem, amateur explosives community. And I freely admit that even the best of us rarely document things up to rigorous academic standards.


However, it is worth mentioning that, although the threat is real, it’s unlikely the nitwits behind this plot could have pulled it off.”

I think TJ is exactly right. While the plot was feasible in theory, it doesn’t sound like the plotters had done enough research to make it work.

Allah u Akbar April 4, 2008 4:28 PM

Q. Will all those who are so smart and skeptical fly on a plane with someone in the toilet trying this?

A. Yes/No

patrick h. lauke April 4, 2008 6:59 PM

i wonder why the authorities didn’t tackle the other side of the problem: ban lavatories on airplanes…or replace the door with a glass panel…or heck, a bucket in the aisle will have to suffice.

rotorist April 4, 2008 7:17 PM

When I too was much younger and much less wise, I managed to use a high explosive to detonate a mixture of household chemicals with impressive results. The household chemicals, all solids, were easily available at the time. The high explosive I produced to use as a detonator could certainly have been concealed as an AA battery. Testing for organic nitrates would probably have revealed the HE, but it wouldn’t have picked up the low-velocity explosive. Probably could have breached the hull of a plane with it, I figure.

There’s enough here that rings true, but the other bits may have been fudged a little so as to avoid giving whackos the wrong idea.

Wyle_E April 5, 2008 12:28 AM

Does anybody eles suspect that shenanigans directed at airliners are intended to divert attention from something else? What else, I don;t know, but I can think of a nice movie plot involving a liquid-natural-gas tanker, and if you cock your foil hat just right, that melamine-in-the-pet-food scandal begins to look rather like a successful test, as does the earlier outbreak of virulent E. Coli.

Angry_Fish April 5, 2008 2:36 AM

The airbus A320, A330, A340, A350 and A380 are all fly by wire. The system relies on computers and cables. Would you even have to enter the cockpit to critically damage the system? Or would you just have to know the weakest point(s) in the system?

Londonman April 5, 2008 6:17 AM

Channel 4 in the UK ran a recent “Despatches” programme on airport security. Bottom line was that it’s all vapourware and designed to con the travelling public into believing that all the various security measures will make their journey safer.

What was really impressive was the explosive expert who filled two 100ml bottles (and so passable through security) with two different chemicals (not named), mixed them together in a bottle bought airside and then detonated. The explosion blew out the side of the airplane fuselage where they had set the exlosive device. So further proof of the inanity of the 100ml fluid limit.

No carry on, no hand luggage, naked passengers …that might work

Uncle Osama Wants You (to be scared shitless) April 5, 2008 12:54 PM

Tang, funny that…

I’ve been flying out of Qatar few days ago and in the duty free they had large cans of that. Mixed with Air Canada’s liquid oxygen it would make a somewhat unstable but usable explosive.

A bomb straight from duty free 😉

posedge clk April 5, 2008 6:13 PM

Why are we concentrating on aircraft?

Synthesis of HMTD or TATP may be difficult in an airplane lavatory.

Doing it in your stateroom on a cruise ship, with no restrictions on liquids, and where the cabin steward will even get the ice for you, is a different matter entirely.

Mark April 7, 2008 1:58 AM

@Stuart Young
Of course, if this actually could produce a small explosion, could they not use that to blow the lock on the cabin door and then take over the cockpit? Something that produces a small explosion in this situation would make a lot more sense then.

Without anyone else on the plane noticing them attaching an explosive charge to the door?

well, ... April 7, 2008 3:14 AM

I suppose that posting a working solution in this thread would constitute a security threat to the poster.

Because of that, the original question could be called an “idiot trap” like they say in french (piège à cons).

Pilot April 7, 2008 7:49 AM


Aren’t all the new military and commercial aircraft fly-by-wire nowadays? Why only mentioning Airbus?

I mean, have any one see the episod of 24 where Jack Bauer was hijacking a airplane by pulling on some wires from inside the cabin (in order to take control of the plane), because the pilot was locked in his cockpit.. What a joke! So maybe fly by wire is safer 🙂

Maybe the new terrorist attack would be to turn on their cell phone during take off 🙂 (joking of course)

Fsck April 7, 2008 10:20 AM

You don’t need to smuggle fancy explosives onto the plane, just wander up to one at Heathrow and slap some semtex on the side of it…

In short: airport security is a complete sham, existing almost totally for show or, as our political establishment said about the security cordon around parliament, “there to deter the casual suicide bomber”.

Pete Austin April 7, 2008 12:33 PM

This plot could never have got beyond the fantasy stage, or even these retards would have noticed that Hydrogen Peroxide is a bleach. FTA: ‘Jury members were shown pages from the diary in which Ali apparently wrote about disguising hydrogen peroxide (‘HP’) with food dye to make it look like Lucozade. He wrote: “Lucozade red 1.5 drops”, and “Check time taken to dilute in HP”.’

Also, if there was a serious bomb threat in the UK, they would never have risked running the Olympic torch across London surrounded by hundreds of vulnerable police.

Gary D April 7, 2008 4:12 PM

It has already been demonstrated that this was a fantasy plot that would have never worked. Mixing liquid explosives on planes takes too much time and creates very noticeable smells before creating very low-grade explosions.

Our fantasy security forces seem to be only good at catching fantasy terrorists.

waterboy April 7, 2008 7:18 PM

Perhaps the real motive was just as it has played out. $tarbuck$ can now charge us $4.00 for a bottle of water inside the secured area that would sell for $1.00 outside.

Anonymous April 8, 2008 2:12 AM

Secondly, unless something is wrong, a passenger jet is on autopilot
for most of the flight anyway.
So the only time this would make a lot of difference is on take off and landing.

There was a Mythbusters episode where they test whether someone from the tower could talk a passenger through the process of landing a jetliner after the pilot dies. This was confirmed, however they remark at the end that nowadays even the landing is done under autopilot. For these big jets, the human pilot only gets to taxi on the runway. Must be a boring job…

Anonymous April 8, 2008 6:20 AM

its completely ridiculous this bomb plot isnt it. i’m currently trying to locate audio from an interview that an army officer gave to a u.s radio show. i’ll have it up soon hopefully.

Jen April 8, 2008 7:33 PM

We’ll never know if it’s feasible or not until we’ve done it! I propose Myth Busters get their asses in gear and bust this one!

Ian April 15, 2008 6:34 AM

I’m actually slightly curious to find out if you can get any good results with an aircraft waste tank full of urine and a few bottles of smuggled-on concentrated nitric acid.

Keith Wright April 15, 2008 8:20 AM

The chances of these guys blowing a giant whole in the fuselage may have been slim, but remember that starting a raging chemical fire in a tin can 3 miles above the ground is no picnic.

Ichabod April 15, 2008 8:48 AM

Whew, that was a close one! My recollection is that Tang was invented so American astronauts would have some “orange juice” in space. They could’ve been killed!

Richard April 15, 2008 11:56 AM

@John Ridley:

90% hydrogen peroxide is what rocket belts
run on:

Yes…but it’s done in an very inefficient way – you can only get about 30 seconds of propulsion from a personal rocket pack before the propellant is all exhausted. The reason for using H2O2 is to produce cool rocket exhaust – it’s monumentally inefficient, but it doesn’t burn the legs of the rocketeer!

Not as Smart as I Think I Am April 15, 2008 5:35 PM

Ok, this probably isn’t an original idea but…

I don’t understand why everyone things you need to “blow up” an airplane to cause damage and death. My non-expert take on it is blowing up stuff (without killing yourself during preparation) is hard in the best of situations, harder on an airplane in flight with limited resources at your disposal.

Instead, why not release a toxic/nerve gas into the cabin. No explosions, but you could still kill a lot of people, especially if it started by knocking people out. Do it at the right time (when people are reading/napping) and no one would notice until it’s too late. If the gas got into the cockpit (so far as I know they’re not on a separate air supply) the plane does down too (not that it would matter by that point).

This is probably going to get me on a watch list somewhere… sigh… Perhaps I can get a movie plot award as compensation?

Osama been Laudanum April 15, 2008 8:39 PM

Me eat beans, light match. Poof!
Me grow fingernail, remove eyeball, splooch!
Me use DC powered nebulizer and Fentanyl patches and zzzzzzzz!
Me use artificial limbs as club. Ungggh-Splat!
Me laugh at Duck and Cover politics – We won, you lost. Me laugh like Urkel.
See you all in h-e-double toothpicks, but I will have my 50 virgins! Inshalla.


Steven April 19, 2008 6:50 PM

These people are smarter than we give them credit for. They are not going to make anything on the plane. The Hydrogen Peroxide/sugar is itself a very powerful explosive, though hard to set off, that is what the pre-made battery detonators are for.

All they do is put the battery det on the side of the bottle, activate it, and you have a liter of HE going off.

Nitroglycerin has this scary ring to it, kind of a taboo, but hydrogen peroxide/sugar doesn’t. Why, I can’t guess. This stuff is almost as powerful as nitroglycerin, and a very similar substance is a commercial demolition explosive. The Hydrogen peroxide/sugar mix is actually more powerful than C-4.

A liter of this stuff is not going to go “poof”, it will be a massive explosion, certainly enough to blow an airplane out of the sky. Someone who has not seen HE first hand really has no idea what it is like, 1 freakin liter would rip big hole in a plane. And this stuff is not corrosive, it would look like a drink, smell like one, and you could easily store it in a drink bottle.

That plot wasn’t a joke, not at all.

John December 18, 2008 11:12 AM

I agree they were probably doing a modified version of the Genie in A Bottle. When you take 30 or 40% hydrogen peroxide and mix it another chemical say manganese dioxide. When they mix an exothermic reaction is created (that gives off heat) by the oxygen in the hydrogen peroxide rapidly decomposing. Here is a video of the experiment but they probably would have left the cap on and not used a plastic bottle.

big bang September 7, 2009 12:12 PM

I recently flew with an air pistol for a competition. The ground crew X-rayed my suitcase but I had to point out the pistol on the screen as they couldn’t find it. I thought opening the suitcase would be easier but this was not “in the procedures” apparently.
Why they had to check it when I had aready declared it is also a mystery.
Yes, there is a real, but small, threat but employing minimum-wage people to enforce the regulations does not make me feel safe.
Whether our respective governments like to keep us under surveillance and scared for their own reasons, I’ll leave others to comment upon.

Peter September 8, 2009 6:11 AM

BBC News showed the liquid chemicals blowing a nasty hole in a dummy fuselage. So, is this real after all?

kmag September 12, 2009 12:34 AM

Also, the London Tube bombings used a main charge of H2O2 and some specialty flour, also with an organic peroxide initiator. Clearly many of you know a lot less about chemistry than you believe.

Gene Douglas September 16, 2009 7:35 PM

This looks more like a kid’s prank, unlikely to knock a hole in an airplane.

I made something similar when I was in grade school, of vinegar and baking soda. Put them in a bottle, close the lid and throw them.

Makes a lot of noise, but not much else.

Gene Douglas September 16, 2009 7:44 PM

The airbus A320, A330, A340, A350 and A380 are all fly by wire. The system relies on computers and cables. Would you even have to enter the cockpit to critically damage the system? Or would you just have to know the weakest point(s) in the system?

Posted by: Angry_Fish

You don’t need to blow up the plane, or even the cockpit. Just blow a hole in the plane, the air pressure goes out and the people not only suffocate, but even if they can get their O2 tubes on, they get the bends from rapid depressurization, which will cripple them for life.

Nobody September 23, 2009 1:40 PM

Glycerin, starch, and sugar are chemically similar. I believe the main (or only) difference is the length of the hydrocarbon. I’ve heard of nitrostarch explosives as a tame form of nitroglycerin. It makes sense that nitrosugars are just more tame.

lothario May 25, 2016 2:19 AM

As I recall…may be wrong…but weren’t the original “jetpacks” fueled by hydrogen peroxide sprayed over silver screens? And didn’t that produce a ridiculous amount of pounds of thrust? In an enclosed area that should be sufficient to blow the cabin.

Peter Clark June 19, 2019 12:18 AM

Nice information you shared here. From hand-carved wooden replicas to factory-produced pop guns and cap guns, toy guns come in all sizes, prices and materials such as wood, metal, plastic or any combination thereof. Many newer toy guns are brightly colored and oddly shaped to prevent them from being mistaken for real firearms.

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