Hiding PETN from Full-Body Scanners

From the Journal of Transporation Security, "An evaluation of airport x-ray backscatter units based on image characteristics," by Leon Kaufman and Joseph W. Carlson:

Abstract:

Little information exists on the performance of x-ray backscatter machines now being deployed through UK, US and other airports. We implement a Monte Carlo simulation using as input what is known about the x-ray spectra used for imaging, device specifications and available images to estimate penetration and exposure to the body from the x-ray beam, and sensitivity to dangerous contraband materials. We show that the body is exposed throughout to the incident x-rays, and that although images can be made at the exposure levels claimed (under 100 nanoGrey per view), detection of contraband can be foiled in these systems. Because front and back views are obtained, low Z materials can only be reliable detected if they are packed outside the sides of the body or with hard edges, while high Z materials are well seen when placed in front or back of the body, but not to the sides. Even if exposure were to be increased significantly, normal anatomy would make a dangerous amount of plastic explosive with tapered edges difficult if not impossible to detect.

From the paper:

It is very likely that a large (15-20 cm in diameter), irregularly-shaped, cm-thick pancake with beveled edges, taped to the abdomen, would be invisible to this technology, ironically, because of its large volume, since it is easily confused with normal anatomy. Thus, a third of a kilo of PETN, easily picked up in a competent pat down, would be missed by backscatter "high technology". Forty grams of PETN, a purportedly dangerous amount, would fit in a 1.25 mm-thick pancake of the dimensions simulated here and be virtually invisible. Packed in a compact mode, say, a 1 cm×4 cm×5 cm brick, it would be detected.

EDITED TO ADD (1/12): Stephen Colbert on the issue.

Posted on December 17, 2010 at 2:13 PM • 55 Comments

Comments

Brandioch ConnerDecember 17, 2010 2:43 PM

While useful in theory, I think it is still too risky for any terrorist to try.

What if you slip and bend your body so that the "pancake" develops a fold that is more easily detected?

Instead, go with the body cavity approach.

Not only that, but should you fail in your attempt to destroy the aircraft, the TSA will ... use your imagination.

Getting the explosive through security should be fairly simple. Getting the detonator through is more difficult.

HJohnDecember 17, 2010 2:51 PM

I think Brandioch is right. The success rate of slipping it through would not be high enough to successfully coordinate an attack.

What's more, this isn't something like a liquid where they'll toss it in the trash and let you go, it's more like a gun where if the find it on you then you'll likely be in jail for the foreseeable future.

ThomasDecember 17, 2010 3:15 PM

@Brandioch Conner
"While useful in theory, I think it is still too risky for any terrorist to try."

Suicide bombers are notoriously risk-averse.

LawrenceDecember 17, 2010 3:28 PM

Brandloch and HJohn,

Isn't getting caught at the backscatter machine with a pancake bomb almost as good as successfully detonating it on the plane, from the terrorists' point of view? The goal of a terrorist is not murder, it is disruption. If the TSA managed to catch an actual bomb at a security checkpoint, air travel would still be disrupted for several days and they would get huge amounts of television coverage. Plus, this plan "degrades gracefully"; if the security guard tells the terrorist that he is about to be searched manually, he can attempt to detonate the bomb right there. Even if it doesn't go off, he's been just as disruptive as the Underpants Bomber and probably forces the TSA to re-evaluate the vulnerabilities in the security line itself.

HJohnDecember 17, 2010 3:30 PM

@Thomas: "Suicide bombers are notoriously risk-averse."
__________

I know you're being facetious, but there is a certain irony to it. Obviously, they aren't afraid to die, in fact they are eager to do so. Ironically, though, they aren't wanting to die just to end their life, they are wanting to die under certain conditions involving the death of others (for motivations I will not go into here).

Basically, I think they are risk adverse insofar as getting caught or killed before they are in a good position to achieve their goal. Once they are in that position, risks be damned.

DoscoJonesDecember 17, 2010 3:32 PM

An electronic detonator could be disguised as a phone, a calculator, or most any other electronic device. A laptop battery contains more than enough energy to get the job done.

If PETN pancakes can be hidden on a person then I have assume it would be easy to hide one of these pancakes inside a carry-on bag. Perhaps packed evenly into the bottom or into the lining?

This line of reasoning causes me to wonder how hard it would be to build an explosive device directly into a working laptop computer.

RandyDecember 17, 2010 3:39 PM

If 20cc's might be detected on your body, then have 5 people attempt to pass 4cc's each. This isn't rocket science.

I wonder what the TSA would do if they actually caught someone smuggling explosives? (Well...after the party and PR campaign. :-) Would they shut down the terminal and search everyone again?

Randy -- justthinkingoutloud

HJohnDecember 17, 2010 3:42 PM

@Lawrence: "Isn't getting caught at the backscatter machine with a pancake bomb almost as good as successfully detonating it on the plane, from the terrorists' point of view?"
_________

I don't think so. Had the underwear bomber been caught by screening, it would give airline passengers some measure of comfort that screening was working at protecting them. When caught on the plane, even though they'd prefer to go out with a bang, failure still has the option of resorting in fear and overreaction.

Brandioch ConnerDecember 17, 2010 3:44 PM

@Lawrence
"Isn't getting caught at the backscatter machine with a pancake bomb almost as good as successfully detonating it on the plane, from the terrorists' point of view?"

It might be. It would depend upon the characteristics of that terrorist/group.

"Even if it doesn't go off, he's been just as disruptive as the Underpants Bomber and probably forces the TSA to re-evaluate the vulnerabilities in the security line itself."

Even easier than that. Just coordinate a few groups to go in with regular hand guns at a few different airports at the same time and start shooting. The TSA would close down ALL the airports.

If that was the goal.

Which is why Bruce is correct about focusing more on real police work instead of trying to block each attack from being repeated.

Doug CoulterDecember 17, 2010 3:49 PM

All this shows is that we're lucky there's no big real threat, and this is all theater. Of course one can make a metal-free detonator, it's just that the pro's don't have a need and there's no advantage in the legal explosives business to doing so.

For that matter, having a separable detonator is a safety issue, something that a person planning to die might well ignore. Doesn't take much primary explosive to detonate PETN or some other easy to make HE's. Could just be placed on the body of the main charge if you had no thought for safety.

If you read the books, there are even explosives you can make that look like votive candles and have no nitrogen -- most if not all current techniques wouldn't detect them. Heck, you could even add scent for realism and have a handy shaped charge with a built in fuse right out in the open.

I for one an stunned more at the failures. Were I going to kill myself, I'd want to make sure of success via some practice shots first. We didn't see so many crazy failures when there were more real terrorists, after all. Did the IRA look so bad at this stuff?

Could it be that all prospective terrorists are really foiled by lack of access to places unpopulated enough to allow them to test their designs?

This stuff isn't hard to learn by doing if you've got a place to experiment (without law enforcement showing up) -- maybe that's the limiting factor in many cases?

Wouldn't surprise me. Perhaps the psychology of the average terrorist today is hampering them from being actually effective, which would be good news, eh?

R.B.December 17, 2010 3:55 PM

@Lawrence, @HJohn:

"if the security guard tells the terrorist that he is about to be searched manually, he can attempt to detonate the bomb right there." Or he could deliberately detonate the bomb while in the densely-packed queue leading to the scanners. My guess is that casualties would be nearly as great there as if an entire plane went down.

HJohnDecember 17, 2010 4:03 PM

@R.B.: "Or he could deliberately detonate the bomb while in the densely-packed queue leading to the scanners. My guess is that casualties would be nearly as great there as if an entire plane went down."
__________

I don't deny that. However, a detonation in an airport doesn't provide as much fear as the thought of a plane hitting someone while they are anywhere. I don't really fear either, but many do.

Best,
HJohn

Clive RobinsonDecember 17, 2010 4:17 PM

@ Doscojones,

"An electronic detonator could be disguised as a phone, a calculator, or most any other electronic device."

How about a pen...

In the late 1980's one marketing gimic. was a "parker pen" with small built in LCD clock and an alarm function...

It would not take much of an effort to convert such a pen to have the actual detonator inside it.

Now it's been a while since I last flew (due to blood clots in legs, lungs and head) but pens used to just get chucked in the tray with your keys and wallet on top. And thus I know that at that time my little LCD alarm pen went through the scanners on more than one occasion...

As for other weapons back then you could still carry on a suit hanger and it would have been a moments work to hide the parts of a "craft knife" in it so it would be extreamly difficult to see on the then baggage scanners.

The simple fact is that an inventive mind is always going to find a way around these scanners one way or another. Likewise no "safe" search is going to pick up on everything.

Thus spending the money on other prevention systems (cockpit doors etc) apears to be a better option....

However it needs to be said that even the most inventive mind cannot get large quantities of materials past even the simplest of the old scnners thus they do have some measure of limitstion

Too OldDecember 17, 2010 5:27 PM

'In the late 1980's one marketing gimic. was a "parker pen" with small built in LCD clock and an alarm function...'

Ah, yes, I remember the Jasper Carrott sketch - the world has changed a great deal, since 'Hi, I'm a Computer Programmer with my own personalised digital pen' was a credible chat-up line!

TimDecember 17, 2010 6:50 PM

@HJohn

Detonating something in line at the scanners would actually create much more of an inconvenience when it comes to air travel.

Blow up a plane, and the one play goes down and all the other planes keep flying.

Blow up the bottleneck area of an airport and you're going to stop all traffic in and out of that terminal for months.

Tony H.December 17, 2010 7:05 PM

@Doug Coulter
"Of course one can make a metal-free detonator, it's just that the pro's don't have a need and there's no advantage in the legal explosives business to doing so."

Other than for anti-personel mines. Say - I wonder what you could disguise one of those as.

CarlDecember 17, 2010 7:23 PM

No system is perfect, and no protection is total. A person willing to sacrifice their life can do a lot of damage.
The goal is to innovate and stay ahead of the terrorist. To make it more difficult for him to plan & execute, to disrupt them and keep them off balance.

Richard Steven HackDecember 17, 2010 9:49 PM

"The goal is to innovate and stay ahead of the terrorist. To make it more difficult for him to plan & execute, to disrupt them and keep them off balance."

That's a game you will never win - because terrorists do it, too - and their options are FAR greater than the security apparatus.

Remember "Casino Royale"? All the terrorist needed was the lock code to a secure area - and how hard would it be to get that? - and a change of uniform that made him look like airport security to get on the tarmac, steal a gas truck and head for a plane.

Once again, this sort of discussion is merely beating a dead horse. You CANNOT defend against a terrorist completely. It is simply not possible. So you make a terrorist group have to plan for another day or week to get around your new fancy security methods, so what? In the end, you still lose. You have to be right every time. The terrorist only needs to be right once.

Right now, the ONLY thing stopping the US from being a hotbed of terrorism is the lack of imagination and competence of most terrorists and the difficulty of operating effectively in the US when the terrorists aren't familiar with the country.

CarlDecember 17, 2010 11:06 PM

@Richard
I've seen that argument so much in Bruce's blog, which is kind of surprising, as it's a really insane argument..
There is only 1 thing keeping terrorists from blowing more stuff up in the US.

It's hard to do. Remember, if it was easy, they would be doing a lot more of it, cause they really-really-really want to.

That's it.. not to complicated.. It's hard for them to get in to the country, it's hard to get the supplies, it's hard to get thru security. It's hard to get that nut case, in the right position, with the right components.

now, notice I didnt say "impossible", just "hard". If the security that we currently have in place, didnt exist, it would be far easier, and more stuff would be getting blown up.. right?

The security we have in place, is the result of innovation that has occured over the past several decades. We only have what we currently have, because of that innovation. As we continue to innovate, we stay ahead of them.

You can NOT defend against terrorism completely, but since when did that become a mandate for doing nothing? Crazy argument...

pdf23dsDecember 17, 2010 11:25 PM

Carl: If the current security actually sucks pretty bad, with all sorts of gaping holes, then that means that the terrorists (who want to target things in America) are incompetent or very few in number. So you're saying the current security doesn't suck, and doesn't have all sorts of gaping holes. I don't see how you can believe that given the comments here, unless you think that the many people thinking of weaknesses are just way off base.

Richard Steven HackDecember 17, 2010 11:43 PM

Carl: You are totally wrong about just about everything involved here, with the possible exception of being hard to get into the country. Actually, it's not hard to get IN country, it's hard to operate here if you're really a suspicious looking foreigner. And even that is a minor detail.

There's nothing hard about sneaking in people, weapons, explosives or anything else including people. It's done all the time by drug and immigrant smuggling gangs to the extent of a multi-billion dollar business.

There's also nothing hard about locating targets to hit.

Please note that in TSA's own tests, approximately SEVENTY PERCENT of the time the testers were able to sneak guns, bomb parts and knives past the screeners. What part of "not hard" don't you get from that fact?

You give me an AK-47, a suppressed .45 handgun, plenty of ammo, and plenty of Semtex and detonators and I could bring any major US city to its knees in a couple of weeks. I mean dozens or hundreds of casualties, police running around like chickens, National Guard troops on every street corner. Go look at the situations Italy or Turkey were in back in the '70's. It could happen here based on just a few dozen mobile terrorists operating in a few major US cities.

A few dozen terrorists with some imagination and the recognition that suitable targets are EVERYWHERE in this country could create havoc in a few weeks of operations.

If it's not happening, it's because the terrorists are just too dumb to do what for-profit criminal gangs do every day in this country.

And terrorists do tend to be dumb. Just study up on the infamous Carlos the Jackal, who was pretty incompetent. Very few of his operations were successful except the Arab oil minister kidnapping (and that was because in those days they had almost zero security) - the rest usually failed miserably. He couldn't even shoot a British store magnate in the face and successfully kill the guy - the guy's TEETH deflected the bullets, for Christ's sakes!

We're just lucky - that's the simple answer. Not the notion that we're just so good at security they can't do anything.

Richard Steven HackDecember 17, 2010 11:49 PM

Oh, and add a good sniper rifle to the list of supplies one would need.

Nothing like capping the odd cop in the middle of the night (or day) to stir things up. Not to mention say, the city's mayor, the state's governor - or their families. How about a Senator or two?

Think that would get things riled up?

Terrorism is not that hard if you're willing to take the risks involved. It's the most effective form of warfare ever devised - IF done competently. Fortunately it's rarely done competently. Hizballah is probably the most competent insurgent group in the world today. And they allegedly already have cells established in the US. Before the US considers bombing Iran, it should think about that.

carlDecember 18, 2010 12:20 AM

- there are LOTS of people that would willingly give their lives to blow things up in the US, fact.
- it rarely happens, fact.

cuz.. we're just lucky.. ok.... that makes sense..

you're hatred for any and all things associated with the gov't/law enforcement is overwhelming all of your capacity to reason (not saying there is a lot there to begin with.. just saying..).
so many folks here so unwilling to acknowledge the work that law enforcement is doing, that they are forced into logic corners like that. very, very wierd..

jgrecoDecember 18, 2010 1:11 AM

@carl

Airport security wouldn't stop anyone from blowing up a plane if they actually wanted too. It *certainly* wouldn't prevent an attack on any of the uncountable targets we don't even pretend to protect.

Your rhetoric is tiring and doesn't fool anybody here. If you were actually interested in discussion then you would consider and respond to the rebuttals you get every time you start spewing this nonsense, instead of parroting your same old lines every time. Surely you have better sites to troll on the TSAs astroturfing budget.

Clive RobinsonDecember 18, 2010 8:19 AM

@ Doug Coulter,

"Could it be that all prospective terrorists are really foiled by lack of access to places unpopulated enough to allow them to test their designs This stuff isn't hard to learn by doing if you've"

Depends on if you are talking home grown terrorists or those in other places.

If not home grown they have the battle fields of Iraq and Afghanistan that the US, UK and other coalition forces created. And as we know from the IED's they have been making they don't lack for skill in that area.

And as Richard Steven Hack notes above getting into the US or UK is not exactly difficult, and once inside a country it is not that difficult to sow fear and discord (think the Washington Sniper). And further even where there is a show of force and technology (TSA) it's by and large lacking in anything aproaching reasonable expectation of the populas at large (which is to be expected when trying to do the virtualy impossible).

It is thoughts like these that I have mulled over and concluded that the attacks we have seen from Captain Underpant's and Corporal Hotfoot where in all probability designed to fail by those supplying the resources. As you are only to aware the materials to make a manually triggered chemical detonator for explosives like PETN are available in many shops and households. Hence the question "why do they appear incapable of making an explosive train?"

Likewise the more recent toner cartridge devices. In this case we know they where not found on normal screening nor on initial searching. They where only found after subsiquent more directed searching (and from some information sources it appears they where not rigged to explode...).

This suggests that somebody supplied very sppecific high grade intel on the devices to the authorities. Possibly even the package numbers...

So the question becomes why are they designed to fail and by whom, and to what advantage?

There are several answers to this question,

The first being lack of competance / experiance which we know from other areas they don't lack.

The second is the "Funds Raiser" idea, that some Governmental Organisation is doing it to ensure tax dollars keep flowing their way. Although possible it is very unlikley for very many reasons (but the likes of Ollie North et al in the past and the current crop of FBI "encoragment" cases leaves a significant nagging doubt).

Thirdly it's either arms or security tech companies doing a "fund raiser". Although I would not put it past any of them to exploit the post 9/11 situation to their own advantage through the politico's, I find it hard to believe any of the companies/ corporations are big enough to risk backing terrorism unaided without being detected.

Forthly, it is high stakes political brinkmanship by the likes of the house of Saud effectivly fighting internal feuds using third parties for fighting proxie wars to set agenders (there appears to be a grain or two of truth in this notion if certain recent sources are to be believed).

There are various other ideas but as I've said in the past neither Captain Underpants nor Corporal Hotfoot where the sharpest tools in the box and certainly gave the appearence of being more of a danger to those around them than to the enemy on a battle field in Iraq or Afghanistan so not realy "insurgent" material.

Also interestingly neither of them appears capable of providing any real intel on the organisations that supposadly recruited and groomed them and provided them with the plans and resources. Which suggests that the organisation has sufficient resources to do this, is very skilled at what it does and importantly has planned to do this considerably prior to the actual acts of terrorism.

This organisational sophistication appears to be further confirmed by the false trail set up around the "printer bombs" it was only by chance the original main suspect (the female engineering student) had a reliable alibi as to her whereabouts. It appears from what has been said in the press that she had been well setup to take the fall by a person or persons who had considerable knowledge about her and possibly access to her possessions.

So these organisations certainly appear to have the skill, sophistication, resources and technical ability to make the bombs expload...

So the question arises as to why three attacks in succession have "apparently failed" over a relativly simple technical issue?

Perhaps they have not "failed" it is possible they where designed not to have a real probability of exploading only look as though they should have done... If so why?

If you think about it terrorists need to advertise otherwise not only does their cause go unrecognised but they also don't get the sponsors that supply them with the required resources.

But they have to be carefull if their message is to bloody then they come across as mad dogs and likewise they won't get the sponsors (which accounts for various hostage takings).

Thus what better than to run the occasional plot which on the surface appears to be an attack but in reality has little or no chance of success of doing very much damage and certainly not bring an aircraft down. But one that will nether the less get a significant knee jerk reaction out of US&UK LEA's and Politico's.

Press wise it's win-win, they don't actually "directly" kill any "inocents" or "non combatents" which is very important to many potential supporters. Yet the damage done to the economy of the US et al makes a political statement that effects every citizen in these countries beyond anything except out right war within the country.

And as a secondary effect keeps the "war on terror" running keeping the "enemy combatents" of the coalition forces on their home ground where they are vulnerable to attack either directly or indirectly via IED etc. (One reason the coalition forces are vulnerable is not enough boots on the ground to have the required overwhelming force to minimise casualties, and this is due to lack of resources...). This also keeps a steady supply of recruits to be "insurgents" to fight the inadiquate coalition forces.

Then there is the tertiary effect that the redirection of resources into the likes of the TSA et al under the DHS umbrella has. It takes resources away from more important areas such as infrastructure development and maintanence, economic development and the attendant social advancment. This potentialy causes hundreds if not thousands of early deaths due to lack of resources for primary and secondary health care, basic jobs to keep families above the poverty line, lack of basic and further education to enable the countries to stay out of long term impoverishment and the high crime this causes, and lack of pensions sufficient to cover basic energy needs, basic health care and even nutrition of those no longer capable of working (think 1800's living without the support of neighbours and relatives).

This "social decomposition" is often "unseen" due to it's lack of news coverage, but can on occasions be fairly visable due to a major event.

Arguably the Government inaction both prior to and after hurricane Katrina is attributable to the focus and funding being on the "war-on-terror" not where it had been in past times.

And some argue that the "government eye" was "not on the ball" with respect to the banks and their diversification from traditional "banking" into "high risk markets" for the same reason...

If only some of these outcomes are true (and some certainly are) then even though the explosives did not go off the attacks where highly successful, possably more so than if the explosives had gone off..

J.D. BertronDecember 18, 2010 10:47 AM

There you go John Pistole.
Now quit wasting our tax dollars on this bogus technology.

CarlDecember 18, 2010 11:24 AM

@jgreco
"Airport security wouldn't stop anyone from blowing up a plane if they actually wanted too. It *certainly* wouldn't prevent an attack on any of the uncountable targets we don't even pretend to protect."

not really true, airport security makes it more difficult to do. Bruce himself acknowledges that: "Look at what succeeded. Because even pre-9/11 security screened for obvious bombs, Abdulmutallab had to construct a far less reliable bomb than he would have otherwise. Instead of using a timer or a plunger or a reliable detonation mechanism, as would any commercial user of PETN, Abdulmutallab had to resort to an ad hoc and much more inefficient detonation mechanism involving a syringe, 20 minutes in the lavatory, and setting his pants on fire. As a result, his actions came to the notice of the other passengers, who subdued him"

You're failing to understand that between doing nothing, and total security, is where we exist.

It's really extraordinarily simple, you cant provide total security, we shouldnt do nothing. The discussion is at what point it becomes to much money spent to get that little incremental security.


CarlDecember 18, 2010 11:28 AM

@clive, congrats, you win the award for most "insane reasoning to explain simultaneously how our security sux, but terrorist havent been able to blow up much"

"Thus what better than to run the occasional plot which on the surface appears to be an attack but in reality has little or no chance of success of doing very much damage and certainly not bring an aircraft down"

"But they have to be carefull if their message is to bloody then they come across as mad dogs and likewise they won't get the sponsors (which accounts for various hostage takings)."

genius.. as long as you ignore reality :-)

SadButMadLadDecember 18, 2010 3:48 PM

A terrorist doesn't need to succeed to cause terror. Making society change to handle the terror is all they need to do. If society becomes afraid of air travel or visiting a public place or mixing with a particular group of people then they have won.

That's the whole point of a terrorist, to make society recognise them. Even making their own kind scapegoats is still a win for terrorists as they can then play the victim card.

Clive RobinsonDecember 18, 2010 9:13 PM

@ Carl,

As your recent responses suggest you have yet to compleate pregraduate education I will recomend a little light reading for you,

Merck Index 14th edition.

Maryadele J. O'Neil (Editor)

ISBN: 978-0-911910-00-1

You can get in Hardcove (2564 pages) or in electronic form, most University libraries will facilitate access if you meet their requirments.

Some of the 10,000 monographs in there will provide you with the information as to why for instance the quantity of PETN in the underware bomb and the chosen method of ignition where unlikley to produce the desired outcome.

@CarlDecember 19, 2010 12:05 AM

@Clive
Thanks man.

I'll just recommend this reading for you, it's from Bruce: "Look at what (airport security process) succeeded. Because even pre-9/11 security screened for obvious bombs, Abdulmutallab had to construct a far less reliable bomb than he would have otherwise. Instead of using a timer or a plunger or a reliable detonation mechanism, as would any commercial user of PETN, Abdulmutallab had to resort to an ad hoc and much more inefficient detonation mechanism involving a syringe, 20 minutes in the lavatory, and setting his pants on fire. As a result, his actions came to the notice of the other passengers, who subdued him"


As you can see (perhaps you'll see that is, maybe not.. you missed it the first time...), the inability to get a proper detonation mechanism thru security forced him to resort to other, far less reliable, detonation mechanisms..
Which is precisely how the security worked..

Get it?

RonKDecember 19, 2010 2:19 AM

@ Carl

Did you even read the article by Bruce that you are quoting? The NYT piece is entitled "A Waste of Money and Time" --- that should have said something to you? What you *don't* quote from it is:

"Exactly two things have made airplane travel safer since 9/11: reinforcing the cockpit door, and convincing passengers they need to fight back."

Not scanners, not "innovation", not staying "ahead of the terrorist".

Clive RobinsonDecember 19, 2010 8:39 AM

@ carl,

A little thought for you at Christmas time,

Anyone who has ever pulled a christmas cracker should realise that you dont need a complication such as a syringe and 20mins playing around in their underpants to make a detonator that does not involve metal.

Heres a little experiment you might want to try.

Go out and buy some fire works and christmas crackers, pull them appart.

Make a pile of the gunpowder and other explosive parts from the fireworks.

Then get that little pull strip from a christmas cracker and put the middle bit into the pile of gunpowder.

Then run your TSA metal detector wand over it to see if it picks it up...

Then while you watch very closly pull the strip so it goes off.

When the smoke clear you might be able to apreciate that you madeddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddd

Clive RobinsonDecember 19, 2010 8:52 AM

@ Carl,

Sorry for the abrupt termination mid post the keyboard driver on the little LG smart phone hung up again, and I had to hard reboot it.

So starting with the last paragraph from my above again,

When the smoke clear you might be able to apreciate that you made an "explosive train" that had no metal parts...

The point about an explosive train is that the detanator is actually quite low energy and often does not have the right charecteristics to set off the main charge. However through intermediary steps either the energy is increased or the charecteristics are changed such that the main charge will detonate and not just burn.

We know from IED's that the likes of various terrorist related groups know this and know it well.

So the question arises why was such an error prone system selected for Captin Underpants, it was almost gaurenteed to fail if not done under ideal conditions.

And it is a question you have failed (as normal) to address in any manner.

CarlDecember 19, 2010 11:56 AM

It isnt clear to me what part of
""Look at what (airport security process) succeeded. Because even pre-9/11 security screened for obvious bombs, Abdulmutallab had to construct a far less reliable bomb than he would have otherwise. Instead of using a timer or a plunger or a reliable detonation mechanism, as would any commercial user of PETN, Abdulmutallab had to resort to an ad hoc and much more inefficient detonation mechanism involving a syringe, 20 minutes in the lavatory, and setting his pants on fire. As a result, his actions came to the notice of the other passengers, who subdued him"

you dont understand.. I realize you dont WANT to recognize it's true.

The reality is, the screening process in place at the time forced captain underpants to resort to the detonation process he attempted to use.
that's just reality
that's what happenned
get it?

I'm sure that the CIA can make an explosive that can get thru security.
but
captain underpants didnt have either the materials, or the knowledge to do so.

As the knowledge is mostly (I would think) available to anyone, it would seem quite OBVIOUS that the issue was getting materials

in any case, wether the issue was knowledge or materials, he didnt have it.
now, clives argument that "he was stupid on purpose cause he didnt really want to blow anything up, he just wanted to scare people"
is of course nonsense.

so, at the end of the day, Bruce's argument is valid: ""Look at what (airport security process) succeeded. Because even pre-9/11 security screened for obvious bombs, Abdulmutallab had to construct a far less reliable bomb than he would have otherwise. Instead of using a timer or a plunger or a reliable detonation mechanism, as would any commercial user of PETN, Abdulmutallab had to resort to an ad hoc and much more inefficient detonation mechanism involving a syringe, 20 minutes in the lavatory, and setting his pants on fire. As a result, his actions came to the notice of the other passengers, who subdued him"


get it?

Clive RobinsonDecember 19, 2010 3:51 PM

@ Carl,

First off you are again not reading what people say and what you do say appears to be at considerable variance with what has been said or reported...

So do you get it?

For instance you say,

"Abdulmutallab had to construct a far les reliable bomb than he would have otherwise"

From what has been reported he neither built or designed the bomb, it was given to him by others.

Which is why I most certainly did not say of Adbulmutallab,

"he was stupid on purpose cause he didnt really wan to blow anything up, he just wanted to scare people"

I suggest as I have said before you read what people have said and not say they have said things they have not. It makes you look at best extreamly stupid.

Do you get it now?

CarlDecember 19, 2010 7:40 PM

@clive
OK, you win. Area 51 is real, the earth is flat, 9/11 was an inside job, making bombs that can get thru security is something that every terrorist learns at birth, and the greatest fear that Islamic extremists have is the disruption and bad press that blowing people up would bring to their annual pledge drive.

lol

Dirk PraetDecember 19, 2010 8:01 PM

@Lawrence
"Isn't getting caught at the backscatter machine with a pancake bomb almost as good as successfully detonating it on the plane, from the terrorists' point of view?"

Perhaps by their PR division, but definitely not in the mind of a deluded mujahid carrying out the attack. Instead of martyrdom and seventh heaven, failure means life - or what's left of it - in a maximum security facility without the possibility of parole, not to mention guaranteed ridicule in the case of the underware and shoe would-be bombers. As Clive is correctly pointing out, it is just mind-boggling how stupid some of these guys appear to be, and how amazingly incompetent the folks supplying them with their explosives. The recent attack in Sweden is yet another fine example thereof.

Personally, I just don't understand why terrorists are still so obsessed with airplane attacks when there are so many easier targets out there. Granted, they're quite spectacular and have a high marketing value, but to me it doesn't make sense and is symptomatic of obsessive-compulsive rather than result-oriented thinking.

In the light of these new revelations, we may expect a serious increase in toddler screening where pantcakes are mistaken for pancakes. It's a dirty job but someone's gotta do it.

kingsnakeDecember 20, 2010 6:49 AM

Ban abdomens!

... and let me be the first to offer mine. I think I could hide several kilos in it. :-(

HJohnDecember 20, 2010 7:58 AM

@Tim: "Detonating something in line at the scanners would actually create much more of an inconvenience when it comes to air travel."
_______

That's a fair point that is largely true. The corrollary, however, is that detonation at an airport only scares people actually participating in air travel, whereas crashed planes can impact anyone anywhere.

I don't fear either, but too many citizens do.

Clive RobinsonDecember 20, 2010 8:21 AM

@ Kingsnake,

You and me both...

A while ago I was standing in my bathrobe when "she who must be obeyed" observed,

"Christ you make a Greek Grannie look good!"

Those we love(d) can be so unkind, and they say "it's for our own good", but if you answer "yes" for "their own good" to "Does my bum look big..." you can expect cold and over salted porridge (oatmeal in US) for breakfast for atleast a week 8(

Bruce ClementDecember 20, 2010 6:22 PM

@Clive Robinson
"So the question arises why was such an error prone system selected for Captin Underpants, it was almost gaurenteed to fail if not done under ideal conditions." and "So the question becomes why are they designed to fail and by whom, and to what advantage?"

This and similar failures have got me thinking. There is no evidence I know that supports this, but is is at least on the surface plausible. We know from the way they crow about it when they "catch" some intellectually inadequate loner that they them selves have groomed that most of the "terrorist" activity in the USA is actually police entrapment.

Perhaps it isn't just in the US. What if the initial push into Afghanistan actually succeeded and wiped out most of the the Al Quaeda leadership and subsequent actions took care of the rest? In this scenario, what we are seeing now are dupes supplied believable, but ultimately non-functional, weapons by government actors.

Sure there is a risk that outside people will develop their own plans uncontrolled by the US Al Quaeda network as may have happened with the 7/7 group, but in general if they can subvert activists into their network and enlist them in doomed projects they can create a lot of noise allowing increasingly draconian measures to increase their control of the US citizenship .

"The rocket bombs which fell daily on
London were probably fired by the Government of Oceania itself, 'just to
keep people frightened'." -- George Orwell

CarlDecember 20, 2010 9:04 PM

@bruce (clive)
now that is really genius at a level I had not thought of, conspiracy at a level I could never have dreamed of.. the US govt wiped out Al Quaeda and installed their own version that continues to attack US targets (ineptly), just to keep it's own citizenry in fear. Creating a situation where the govt can step in and say "Fear NOT, we are the US GOVT, we are here to protect you, now just huddle together in a qivering mass so that we can get you plugged in to the matrix,, err... ensure your safety"

breathtaking..

SteveADecember 21, 2010 3:56 PM

About 300,000 passengers a week fly out of JFK alone.

From the TSA website two random weeks(for the whole of the USA)

TSA Week at a Glance: 11/22/10 through 11/28/10
7 artfully concealed prohibited items found at checkpoints
14 firearms found at checkpoints
6 passengers were arrested after investigations of suspicious behavior or fraudulent travel documents

TSA Week at a Glance: 12/13/10 through 12/19/10
3 artfully concealed prohibited items found at checkpoints
11 firearms found at checkpoints
10 passengers were arrested after investigations of suspicious behavior or fraudulent travel documents


So,
An average of just over 25 incidents in a week, and 35 potential 'terrorist plots' averted!

Let's be honest, most of these are probably people forgetting they had a gun (or ammunition) on them or trying to sneak through a pair of nail scissors or can of hairspray. And that is with x-ray technology in place!
I'm not saying the people shouldn't be punished, I just don't think they were all terrorists.

Fraudulent documents? Sure. All terrorists use those, after all you don't want to get caught buying a ticket.

But the TSA did stop ALL the terrorist airline plots in those periods (because no planes were hijacked).

If a private company was paying for the TSA service I'm not sure they would justify the cost of the above interception rate.

Fortunately the US taxpayer has deeper pockets.

6.3 billion dollars a year at the moment, about six times the cost of building the Twin Towers that started all this.

But I'm sure they can spend a bit more to make the flying public feel safer.

Peter GerdesJanuary 1, 2011 5:32 AM

People seem puzzled as to why there aren't more successful attacks given that they can easily work out how to foil the visible countermeasures. The answer is simple: psychology and insufficient support networks.

Humans are social animals. We rely on the support of our communities to encourage us to undertake dangerous work while evolutionary pressures have virtually squeezed true mass murderers (people willing to kill many others without a socially approved grievance) out of the gene pool and those that are left are more likely to be sociopaths than crusaders.

I mean try imagining that you were reliably informed by your time traveling future self that your neighbors teenage son would grow up to be the next hitler and slaughter your family. Despite your moral certitude and willingness to sacrifice for your family imagine how hard it would be to perform that murder compared with how much easier it would be to shoot that same teenager as part of a special ops team all of whom know about his future and support the decision.

Terrorists are no different. They can only talk themselves up into violence through communication with likeminded other individuals. Kazinzki was truly exceptional in his willingness to kill unassisted for his cause and even he couldn't resist talking to the press. Even amoung those sympathetic to the terrorists ends those willing to personally assist in such a scheme are few and far between. Even those who support terrorism will often act to stop their friends and loved ones from being the ones to give up their lives in the cause.

The net result is that terrorists tend to be half-assed solo attempts (like the underwear/shoe bombers) or must reach far outside of their usual social circle to find sufficient comrades in arms. Thus for each successful link made to another aspiring terrorist a terrorist must risk many potential tip-offs or sting operations.

This was the importance of disrupting the training camps in afghanistan under the taliban as they posed as serious threat by creating a well known hard to monitor enviornment for terrorists to met each other.

EldonJanuary 18, 2011 7:58 AM

its would be trivial to check a suitcase full of concealed via a plethera of creative methods.

40 pounds of high grade explosive should blow the entire cargo bay out the bottom of the plane.

have it set to detonate on the connecting flight. you don't even have to get on the plane.

WaelJune 9, 2012 1:14 PM

@ Eldon,

Some airlines match checked in bags with travelers. If a traveler fails to go on the plane, their bags are removed from the cargo bay. This happened to me once on British Airways. After they closed the cabin doors and the plane was about to move, they stopped that and announced that they are removing a bag for a passenger that failed to board the plane. Not sure if this was a connection flight for that person. So the hope is Airlines do make that no-brainer check.

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