HOWTO defeat the shoe-scanner at Heathrow
Bruce Schneier just passed through Heathrow Airport and noticed that they're speeding up the shoe-scanning process by having you go through a metal detector first and then have your shoes scanned at a second system. Being a security guru, he gave it ten seconds' thought and figured out how to defeat it.
Of course, X-ray machines are useful for spotting metal, not plastic explosive, so none of this stuff matters anyway. Ho ho ho. LinkHere's how the attack works. Assume that you have two pairs of shoes: a clean pair that passes all levels of screening, and a dangerous pair that doesn't. (Ignore for a moment the ridiculousness of screening shoes in the first place, and assume that an X-ray machine can detect the dangerous pair.) Put the dangerous shoes on your feet and the clean shoes in your carry-on bag. Walk through the metal detector. Then, at the shoe X-ray machine, take the dangerous shoes off and put them in your bag, and take the clean shoes out of your bag and place them on the X-ray machine. You've now managed to get through security without having your shoes screened.
(Photo: Travel Hungry Shoes, a Creative Commons Attribution photo from Stuporglue's Flickr stream)
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What are those shoes so angry about?
@#1 for not unknotting their shoelaces before one steps out of them? :)
Don't the shoe scanners look for plastic explosives? I thought that's what they were doing.
I like flying now it is all so safe and everything....
As a result of EU laws you are not allowed bring "dangerous" items like nail clippers through the security screen.
Thankfully, in my nameless local Airport, just 10 feet from the Xray machine you can buy a nail clippers to replace the one they've just confiscated from you at the metal detector.
Of course it is just for our safety I'm sure....
And how are you supposed to change your shoes without anyone noticing? Last time I went through there was only a few yards between the metal detector and the X-ray machine, a constant flow of passengers and nowhere to pause hidden from view as you perform this suspicious act.
Besides, they X-ray your bag as well.
Nelson C...
You're assuming that if they see the shoes in a bag, they'll take them out and actually scan those as well as the ones on your feet.
I think this method of defeat relies on them placing a different value on worn vs. carried shoes.
Yeah...stupid.
Why do our shoes hate America so much? Is it all the gum on our sidewalks?
I've been doing this little trick for over a year:
http://www.kinkyangel.co.uk/images/373BN.jpg
Walk through security wearing the New Rock boots as shown above. They unzip when you're told to scan them. Get them scanned. Reach into hand luggage bring out big plastic bag, extract normal shoes, put New Rocks in bag...
The walk-through detectors can generally only find metal (except the newer, rarer backscatter variety), but the conveyor-through can find a whole lot more than metal. Take a look at the output screen sometime--every different color is a different material (via density and metal content.)
Every time I have been through TSA everything got scanned via conveyor, shoes, bags, belt, wallet. No exceptions at all. It was still less paranoid than the security at the Munich airport which features two separate security screenings.
And no-one would notice you doing this?!
Whew! Now if I can get the mall cops to stop tagging my car when I leave my Christmas presents on the back seat, I'd feel much safer.
I did 100-120 flights a year for a while in the continental U.S. and you pretty much don't go through the metal detector with shoes on. The detector operator looks at your shoes and decides whether they look too scary, which has been virtually everyone's shoes in my observation. The experienced travelers always put their shoes on the carryon x-ray, while the inexperienced travelers (the one that's always right in front of you) get an outstretched arm and a stern command to go back and put their shoes on the conveyor, upon which they confusedly do an about-face and take about 3 minutes to untie their shoes.
They put my little birks through the x-ray thing once and let me wear big huge boots another time. It's totally random I'd say!
My chucks are dimensionally transcendental. I just keep all my luggage in there.
Why don't you just e-mail Al Qaeda directly?
It doesn't take a genius to get around these systems, only the will to do so. If somebody wants to get something on a plane there are 1 million ways to do so undetected. All the hoops we have to jump through are just a huge waste of time, unless you think that giving the former trailer park kings that now compose the TSA huge ego and authority boosts is a good thing.
Hey IBURL, sweet stereotype of people living in trailer parks.
Isn't this what one of the prisoners did in Escape From Alcatraz?
I travel out of Heathrow regularly, and on many occasions I have simply just walked around the shoe scanner machine, essentially making the screening optional.
I was running late for a flight a few months ago, and to my surprise the security official just waved me around the machine, which had a fairly large line of people waiting. Since then, whenever I travel out of Heathrow, I just walk around the machine, and I have not been challenged once, regardless of whether I'm suited and booted or wearing jeans and a tee.
This just shows how absurd airport security is nowadays. Letting just one person through unscreened makes the entire screening process close to futile.
Um, at no time in the last five years have I been able to walk through a metal detector while wearing shoes. Even if I had, the metal detector and xray scan occur side by side- shoes and carry on baggage/belongings pass through the conveyor at the same time as the passenger walks through the metal detector. This is based on my experience at six different airports, and is standard for US domestic security layouts I presume. I don't know where you came up with this plan, but it's pretty unrealistic.
D'oh! Never mind, noticed this was a Heathrow only deal...
Perhaps at Heathrow they're putting shoes through x-ray machines for some reason, but every airport I've been to in the US, they swab them with chemical pads that trap ions, then insert those swabs into a machine that does an assay on the trapped ions to conclude whether or not the shoes contain explosive materials. They'll also do this procedure on a carry-on bag if they're for any reason suspicious.
Won't work in the US. The shoes go through the same x-ray machine as carry-on bags, and security has no compunction about telling you to remove the shoes from the bag and send both through the machine again. That's what happened to me when I bought a pair of shoes on my last trip.
dbutler1986, I think you're confusing primary and secondary screening. At primary screening, people pass through magnetometers, shoes (and everything else) pass through X-rays. Every US airport does this, as does every European airport I've used, as well as Narita, Melbourne, Syndey, Cairns, Toronto, Montreal and Vancouver.
If you get pulled into secondary, they swab your shoes and put the swabs into an explosive residue detector, but secondary is given to less than 5% of the passengers.
As skreidle noted in #9, modern X-Ray machines are able to do a lot more than find just metal, although that does happen to be one of their strengths.
Most newer devices have the ability to sort based on organic, in-organic and blend materials. Regarding Heathrow, they use (as many airports do) the Smiths-Heimann Hi-Mat capable scanners.
A properly trained person doing sufficient evaluation and detection should have little problem detecting a wad of plastic explosives or something "irregular" in most cases.
The issue is, as I've noted often, TSA and other agency screening officials are running so many people through at such a high rate of speed, accurate assessment is virtually impossible.
Couple this with an apparently lack of adequate training, and the entire process is reduced to a finger exercise.
I frequently travel with a carry-on bag filled with electronic gear: laptop, digital SLR, couple of lenses, iPod, several cell phones, headphones, external hard drive, Nintendo DS, and all the assorted accompanying cables. I then put my Zippo lighter in a small bag in the same bag, and chuckle as it goes through x-ray. *I* can see it, plain as day, but there is so much other "interesting" stuff, the screener typically has me open the bag, glances over all the gear and waves me on.
In Frankfurt, I forgot until I reached the line that I had a leatherman "Wave" knife in my bag. Worried that it would be confiscated, I oriented it in such a way that it would appear less as a "knife" and more as a block of metal, and placed it along-side my external hard drive.
Sweating bullets (aren't they supposed to have people that can spot people like me?) I observed a screener operating a machine fully engaged in conversation with the person next to to them. At no point did they even *look* at the scanner, in fact, they didn't even acknowledge my existence.
The point is, policy, procedure, technology, and so on are only useful when the staff are trained and attentive. Otherwise the entire thing is just a an inconvenience for the honest folk flying, any genuine criminals are free to move about the air.