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Backscatter X-Ray Machines Easily Fooled

Posted by Soulskill on from the my-pants-pockets-are-not-bombs-stop-grabbing-my-@&# dept.

Pinckney writes "A paper by Leon Kaufman and Joseph W. Carlson in the Journal of Transportation Security asserts that x-ray backscatter machines are not very effective (PDF) even in their intended role. While carelessly placed contraband will be detected, the machines have glaring blind-spots and have difficulty distinguishing explosives from human tissue. As they write, 'It is very likely that a large (15–20 cm in diameter), irregularly-shaped, cm-thick pancake [of PETN explosive] with beveled edges, taped to the abdomen, would be invisible to this technology. ... It is also easy to see that an object such as a wire or a boxcutter blade, taped to the side of the body, or even a small gun in the same location, will be invisible.'"

8 of 342 comments (clear)

  1. The next generation... by John+Hasler · · Score: 2, Interesting

    ...will automatically detect suspicious areas of the image and rescan them slowly at high power.

    Or they'll just go to transmission x-ray scanners concealed in the metal detector frame.

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    Warning: this article may contain humor, sarcasm, parody, and perhaps even irony. Read at your own risk.
    1. Re:The next generation... by MoonBuggy · · Score: 5, Interesting

      Thing is, we don't even really need "a better way of detecting terrorists". The incidence of terrorism against airlines is practically a rounding error and as we've seen, the TSA has been unsuccessful in preventing the (very few) attempted bombings in the recent past yet the attacks still failed. If we removed the theatre and replaced it with nothing, maybe keeping a few basic and effective measures to discourage obvious attacks, we'd be better off, and the risk would still be negligible. If we replaced it with something actually effective then that'd theoretically be even better, but most effective methods are expensive, invasive or both and I'm unconvinced that they would be worthwhile considering how low the risk is.

    2. Re:The next generation... by jfengel · · Score: 3, Interesting

      the TSA has been unsuccessful in preventing the (very few) attempted bombings in the recent past yet the attacks still failed.

      Arguably, the failures were caused by the fact that they had to go to such great lengths to conceal the explosives. If they had brought on a nice, simple stick of dynamite, they'd almost certainly have succeeded.

      You don't actually have to prevent 100% of attacks for security to be useful. A few foiled attacks are extremely handy in providing information and causing your opponents to waste time and energy. But when an attack is partially successful, you do need to increase security to some degree to foil a repetition.

      It may not perfectly foil repetitions, but forces your opponents to change tactics, and that doesn't happen instantaneously.

      It's not enough to posit that there's something both less intrusive and more effective. You have to actually show such a thing. I don't know if backscatter is optimal for the purpose, but I know it's more effective than taking no action.

    3. Re:The next generation... by sumdumass · · Score: 1, Interesting

      Opportunity strikes where opportunity is present. The greater the opportunity, the greater the risks people are willing to take with the opportunity. And you are right, if you only consider the bomb itself, you are not going to carry enough explosives into either venture to kill more then about the same amount of people with the bomb.

      Here is what makes a plane a little more attractive then a subway or sports stadium. You already mentioned the collateral damage which is what I believe the Christmas underwear bomber was looking for. But people are generally afraid to die. Sure, you can train people not to think about it or so that required action is automatic or instinctual and not a process interfered with by the thought of dieing, but in general, they are afraid. This is even true when people claim they are not afraid to die, often in the life and death situation, they won't want to die (there might be some who still don't care, but those get weeded out pretty quickly by the fact they already died).

      So what's stopping a terrorist from getting on a plane with two bombs, one relatively small and removable and the other large enough to bring the plane down? All he would have to do is go to the bathroom, drop one bomb off, move to the other end of the plane and set it off. If it kills anyone or not, it doesn't matter, but it's going to get everyone's attention including the pilot's. Now, the terrorists stand up, announces he has another bomb that will be detonated if he presses a switch of his finger is removed from it. (imagine a 3 way toggle where center is neutral and one way is one#1 and the other way is on#2). So he says they are all his hostages, he wants the plane diverted to X location where they will all be released once his demands are met and he wants access to the cockpit and communications systems to verify it's happening else he will detonate and bring the entire plane crashing down.

      So now the pilot has a glimmer of hope, a planted chance of not dying. Does he A: refuse to open the door and let the terrorist kill everyone or does he B: assume he was telling the truth and his intentions are not to kill everyone and they might live if he gives them access? Well, the pilot isn't some hard core trained marine capable of doing whatever it takes to complete the mission even if it means his life will be over. It's highly likely that the pilot will want to live and he will divert the plane and give the terrorist access.

      Now the locked door is negated and the possibilities of using the plane as a weapon is alive again. All the terrorist needs to do is state that they all will live if the plane lands on the ground safely and do it in a way that the concerned citizens don't think they are doomed. Then at an opportune time, cause it to crash into some building or sports event or whatever without enough time for the people/pilots to react to stop it.

      I agree that the threat is over blown. But without the reactions to the threat, it would likely be more of a reality. Using a plane as a missile has become a lot harder in today's times. A big different between blowing up the security line at the airport and using a plane to crash into a building is that to some degree, those people waiting in line at the airport connected to the dangers. It's still a tragedy but it's a situation they consciously put themselves in. You going to work and noticing a plane crashing into your building when getting a cup of coffee is nothing you consented to. It's not a danger you assumed by waking up and living your boring life. The security at the airport is for the people not flying probably a little more then the people who are flying.

  2. And in related development by hey! · · Score: 5, Interesting

    The Boston Globe reported today that a the mutilated body of a teen boy found last month in a Boston suburb probably fell out of the wheel well of an airplane he is believed to stowed away on. Several articles of his clothing were found scattered along the flight's approach to Boston's Logan Airport.

    Earlier this year in Japan a body was discovered in the wheel well of a flight originating at New York's JFK. Investigation later revealed that the unfortunate hadn't stowed away in New York, but in Lagos Nigeria *two months earlier*.

    What does this tell you about all this body scanning hoopla? We're building a fortress that sports a fearsome looking portcullis but has open windows on the ground floor.

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    Post may contain irony: discontinue use if experiencing mood swings, nausea or elevated blood pressure.
  3. Milimeter wave RF scanners too? by hawguy · · Score: 4, Interesting

    Does this same condition exist for the Millimeter Wave RF scanners too, or do they have better resolution or discrimination abilities?

    I haven't traveled much since these scanners went into effect, but so far I've only seen the RF scanners.

    Last time I encountered one I asked the TSA rep if it was RF or X-ray, and she said "It's millimeter wave, and it's the same as an ultrasound". I told her that that can't be true since an ultrasound doesn't use RF energy, and she said "It *is* the same, now move along". I reported her misinformation to a supervisor, but I'm not sure he even understood the difference between ultrasound and an RF scanner.

    I'm fine with the RF scanners (I don't think they are all that effective since a determined terrorist will use one of the many holes in airport security to bring in his weapon -- plus my "junk" isn't all that interesting), but I don't like being lied too (or worse someone directing me into a device that she doesn't even have a basic understanding of -- surely the difference between sound and RF energy is not too hard for a TSA agent to understand)

  4. Re:It's theater... by adolf · · Score: 3, Interesting

    And if you actually try it instead of just thinking about it, you'll find that both broken (cracked) and scratched records can behave very similarly upon playback.

    I've been around long enough that I've tried both.

    So, in the interest of pedantry, I'd like to say that while your new word usement does seem to be valid, its validation does not seem to in any way invalidate the validity of the previously-valid phrase.

    Please feel free to use both terms interchangeably in such contexts as this, for they are synonymous.

    Thanks!

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    Kid-proof tablet..
  5. Re:Solution by speculatrix · · Score: 4, Interesting

    the TSA have already forced a woman with a prosthetic breast to subject herself to intrusive scrutiny: http://www.cbsnews.com/stories/2010/11/19/national/main7070415.shtml

    so, no doubt the TSA staff will soon be equipped with endoscopes and be trained in keyhole surgery to prevent terrorists implanting bombs inside their bodies.