Defeating the Shoe Scanning Machine at Heathrow Airport

For a while now, Heathrow Airport has had a unique setup for scanning shoes. Instead of taking your shoes off during the normal screening process, as you do in U.S. airports, you go through the metal detector with your shoes on. Then, later, there is a special shoe scanning X-ray machine. You take your shoes off, send them through the machine, and put them on at the other end.

It’s definitely faster, but it’s an easy system to defeat. The vulnerability is that no one verifies that the shoes you walked through the metal detector with are the same shoes you put on the scanning machine.

Here’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.

This works because the two security systems are decoupled. And the shoe screening machine is so crowded and chaotic, and so poorly manned, that no one notices the switch.

U.S. airports force people to put their shoes through the X-ray machine and walk through the metal detector shoeless, ensuring that all shoes get screened. That might be slower, but it works.

EDITED TO ADD (12/14): Heathrow Terminal 3, that is. The system wasn’t in place in Terminal 4, and I don’t know about Terminals 1 and 2.

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Posted on December 14, 2007 at 5:43 AM • 93 Comments

Comments

Matt • December 14, 2007 5:53 AM

Nooooo! Don’t tell them! They’ve only just got Heathrow usable again, by dint of such clever workarounds and streamlining. You know, I know, the government knows, the airport security know, that these measures are stupid. But while the politicians insist on having the measures we might as well make them as painless as poossible.

Bob • December 14, 2007 6:16 AM

I agree with Matt. Heathrow is just about bearable at the moment, though they still do the stupid liquid screening. And stop pointing out that essentially everything they do is pointless. It keeps the security guys off the streets, they’d be night club bouncers with a grudge.

I fly internationally about five times every year which is often enough to be utterly bored, rather than intimidated or reassured, by airport security. I was pleasantly surprised the first time I didn’t have to take my shoes off (though this didn’t stop 80% of people doing it anyway, it must be habit forming). My surprise turned to laughter when, after 100 yards or less, we all reached the shoe scanning machine.

Jonathan Thornburg • December 14, 2007 6:30 AM

Fortunately, the continental Europeans have a much more user-friendly system: they don’t do shoe scans in the first place. Nor do I remember shoe scans on recent trips to Canada and Australia.

Of course, if you really want to see security screening that’s both (a) done fairly thoroughly, and (b) very user-friendly, go to Berlin’s Tegel airport (TXL). They have a separate X-ray machine/operators/line for each pair of gates, with typical wait times from 30 seconds to 3 minutes. Other major “old Europe” airports (eg Frankfurt FRA, Heathrow LHR) that I’ve been through recently have all had centralized X-ray screening posts serving many gates, and I’ve sometimes had to wait as long as 10 minutes.

For me the biggest pain by far at LHR is the limit on only one carryon bag per person allowed through the security screening. This is completely independent of any airline limits on cabin baggage (it even applies to 1st class!). So no more carrying a food bag for long flights, unless I can stuff it into my backpack along with my laptop, N different countries’ power cords, important papers, etc etc. My spouse always flies with some portable medical equipment, and even that counts against the one-bag-no-more-than-some-rather-low-size-and-weight
limits. 🙁 🙁 🙁

Oren • December 14, 2007 6:37 AM

There is a much easier way to defeat the security: skip the airport and go blow up a shopping mall.

Pete • December 14, 2007 6:42 AM

I like traveling with my camera in it’s own bag, so going though Heathrow is a pain – a laptop bag and camera bag aren’t welcome. However, if I have both, I take out my laptop(s) from one bag, stuff the camera bag into the laptop bag, put everything through the scanner (laptops in their own trays) and repack on the other side. No one has said anything to me yet, even though I do it right in front of them on both sides.

FlewThroughHeathrow • December 14, 2007 6:59 AM

Or just take a baby with you when travelling through heathrow. They wave the whole family of the baby around the shoe screening.

Interestingly the order is (1) normal security screening, (2) outgoing passport check, and finally for people without babies (3) shoe check

Stephen d • December 14, 2007 7:03 AM

Last time I was at Heathrow, the system was so chaotic that my wife and I just walked passed the shoe scanner altogether. Maybe that’s the way of the future: Optional security if you need the reassurance 😉

Aj • December 14, 2007 7:04 AM

Thats far too complicated….. Its much easier than that at Stansted airport in the UK.

I frequently fly via Stansted airport (2-3 times per month). At the shoe xray, security pick most passengers, but not all passengers to check their shoes.

When I have worn causal clothes, or looked at the security guards they have picked me out to xray my shoes.

But when I am wearing a business suit and I walk quickly, looking straight ahead, they don’t pick me out to xray my shoes!

This technique works very consistently and I haven’t had my shoes xrayed since I discovered this last year.

Richard Veryard • December 14, 2007 7:11 AM

Before publishing vulnerabilities, one need to judge the likely outcomes. Perhaps some people think it would be a good thing if air travellers are subjected to further stupid harassment (and risk of foot infection) at Heathrow, because this would reduce the quantity of pointless tourism and even more pointless business meetings.

But the people who would suffer the worst from a further tightening of shoe-related security would be fashion shoe designers, with carry-on bags stuffed with thousands of pounds worth of glamorous stilettos and supercool trainers. Why don’t you publish that vulnerability as well, drive shoe design underground, and force fashion victims to wear sensible shoes instead?

Fridz • December 14, 2007 7:12 AM

Slightly off-topic but related: It has always amazed me that with the extensive airport security (theater) it comes as a shock to hear the flight attendants announce that the use of electronic devices during take-off and landing is prohibited. Passengers are kindly asked to refrain from using their laptops and other electronic devices during these times. Cell phones are allowed in carry-on luggage but passengers are also trusted to keep them turned off.

If this is really a risk to the plane, why are passengers treated there as trustworthy? This sounds a bit like replacing airport security with a sign saying: “Passengers are kindly requested to refrain from activating any explosive devices on the aircraft. Thank you for your cooperation”.

Vlad • December 14, 2007 7:25 AM

That’s strange.

I have passed through Heathrow three times in the last one year (most recently just a couple of weeks ago) and never encountered the decoupled scanning. I was asked to take off my shoes (plus jacket, belt, watch, you-name-it) at the first (and the only) checkpoint.

licky lindsay • December 14, 2007 7:32 AM

@Fridz: because the idea of phones and laptops interfering with takeoff and landing is an urban legend, pure and simple.

jaq • December 14, 2007 7:44 AM

I went through Heathrow (T3) in the summer, and the shoe-scanning appeared to be optional – there was no barrier to stop you walking past it, and it wasn’t very clear if there was any checking that everyone went through it.

Steveoriino • December 14, 2007 7:47 AM

@Fridz,
It’s actually about making sure the passengers are paying attention to their surroundings “in the event of an unscheduled landing.” (See: situational awareness)

In other words, when you’re trying to get to the emergency exit, but the back half of the plane is engulfed in thick black smoke, do you really want to be tripping over the idiot who doesn’t know what’s going on because he’s still plugged into his ipod? Or be stuck behind the businessdrone who’s trying to shove his multi-thousand dollar laptop into his bag?

This is why security theater is wrong: it takes credibility away from measures that actually can make you safe, particularly measures that protect against rare events.

Deadskin • December 14, 2007 8:02 AM

I can’t believe you are telling the terrorist how to win, oh my god, they would have never figured that out … j/k
You just ruined the perceived sense ofsecurity we all need so we can go on with out lives thinking no one can hurt us now.

Ross • December 14, 2007 8:06 AM

Last time I went through Heathrow, the man watching the shoe scanner was so bored we was barely paying attention to the screen. Whilst I was in the queue and could see him and the monitor, I counted three shoes go past whilst he was looking at the queue forming…

simpler • December 14, 2007 8:07 AM

Why even risk being seen switching shoes? Just leave the second pair in the carry on in the first place as they don’t seem to require extra shoes to be scanned by the special machine.

Bruce Schneier • December 14, 2007 8:09 AM

“It has always amazed me that with the extensive airport security (theater) it comes as a shock to hear the flight attendants announce that the use of electronic devices during take-off and landing is prohibited.”

The announcement that always disturbs me is: ” Your seat cushion may be used as a flotation device.” What do you mean, “may”? If you don’t know, who does?

Bruce Schneier • December 14, 2007 8:10 AM

“‘It works’ as in ‘we had no exploding shoes on planes so scanning shoes makes sense’..? ;)”

I did say: “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.”

Bruce Schneier • December 14, 2007 8:12 AM

“They’ve only just got Heathrow usable again, by dint of such clever workarounds and streamlining.”

It’s just barely usable. I get to go through the “Fast Track” lanes; otherwise it would still be horrible. And going through security while changing planes still takes hours unless you can find an official to let you cut the line.

Bruce Schneier • December 14, 2007 8:14 AM

“For me the biggest pain by far at LHR is the limit on only one carryon bag per person allowed through the security screening.”

Agreed, and it’s the reason I don’t change planes in Heathrow anymore if I can at all avoid it.

Bruce Schneier • December 14, 2007 8:16 AM

“I have passed through Heathrow three times in the last one year (most recently just a couple of weeks ago) and never encountered the decoupled scanning. I was asked to take off my shoes (plus jacket, belt, watch, you-name-it) at the first (and the only) checkpoint.”

It’s at Terminal 3.

Bruce Schneier • December 14, 2007 8:18 AM

“Interestingly the order is (1) normal security screening, (2) outgoing passport check, and finally for people without babies (3) shoe check.”

Outgoing passport check? I can’t remember the last time I had an outgoing passport check at Heathrow.

Bruce Schneier • December 14, 2007 8:21 AM

“Why even risk being seen switching shoes? Just leave the second pair in the carry on in the first place as they don’t seem to require extra shoes to be scanned by the special machine.”

I don’t think it’s a special machine; I think it’s just a normal x-ray machine. So according to them the threat is shoes that successfully go through a metal detector, and the threat can be countered by x-raying shoes. (Again, ignore the question about whether this is a realistic threat.) So the trick is to walk through the metal detector with the dangerous shoes on, and then swap shoes and walk past the shoe x-ray machine with the dangerous shoes in your carry-on bag.

simpler • December 14, 2007 8:21 AM

Next time I pass through one of these, I’ll take a second pair of shoes carry on.

The dress shoes that make the metal detector beep will be in the bag. I’ll wear the comfy no beep ones.

I wonder what will happen?

Actually, come to think of it. I may have done this before and not realised it.

Matt • December 14, 2007 8:25 AM

“It’s just barely usable. I get to go through the “Fast Track” lanes; otherwise it would still be horrible. And going through security while changing planes still takes hours unless you can find an official to let you cut the line.”

I can believe that about transfers, but the last few times I’ve flown out of Heathrow it’s been at T3, and I’ve stood in line at the ‘fast track’ for longer than I would have queued if I’d been going coach! It’s very dependent on the time of day, but at least there aren’t lines out of the building like there were for a while last year.

simpler • December 14, 2007 8:28 AM

“I don’t think it’s a special machine;”

Arrrgghh! Wonderful.

Wouldn’t it have been cheaper to put the shoes in a plastic tray and pass them through the regular X-Ray! Does that really slow things down that much?

Or is this so they can tick off the box that says “Check shoes”.

Kaszeta • December 14, 2007 8:30 AM

Last time I was at Heathrow, I avoided the long queue at the shoe scanner by doing things the quasi-American way: I put my shoes in my carryon that was x-rayed, and they waved my sock-clad self right by the shoe scanner, saving me about 10 minutes.

simpler • December 14, 2007 8:33 AM

@Frank Koehntopp

There was a pre 9/11 ad in Australia with two women working airport security. An athletic chap goes through and the machine beeps. Belt off. Repeat. Beep. Etc. Etc. Until shirt off. Clear.

After he leaves you find out the guards could make it beep at will.

A • December 14, 2007 8:35 AM

I can’t wait until someone tries to blow up a plane with an artificial penis crafted from plastic explosive, or by concealing OMGDEADLY poison in a “fat suit”.

ilmari • December 14, 2007 8:43 AM

I’ve flown from Heathrow (Terminal 3) 6-8 times this year, and nobody has ever stopped me from just walking straight past the shoe scanning line, and I’ve seen lots of other people do it as well.

No need for tricks like putting the shoes in the carry-on and walking sock-clad.

Rob Kendrick • December 14, 2007 8:44 AM

I noticed exactly the same issue at London Stansted last week. Even worse, the seating area where you put your shoes back on again is around the corner and out of site of the security check zone.

Salzburg airport has a dedicated scanning machine that you put your feet on and it scans while you’re wearing them.

Sarah Williams • December 14, 2007 8:51 AM

Seconding ilmari. I’ve flown out of Terminals 3 and 4 at Heathrow multiple times over the past few months. Kept to the side and walked past the shoe screening each time. No one has ever stopped me.

MRB • December 14, 2007 8:58 AM

I went through Heathrow Terminal 2 on Monday, and I had to take my shoes off and feed them into the same X-ray machine that was scanning my case. It may be dependent on which terminal you use, but I hope not.

jeff • December 14, 2007 9:06 AM

@licky

@Fridz: because the idea of phones and laptops interfering with takeoff and landing is an urban legend, pure and simple.

Partly true, partly false. Its true that it is extremely unlikely that they’ll affect the actual takeoff or landing, but there is a risk (most likely small) that they’ll affect one or more of the navigation instruments, which could affect the approach and/or departure path.

If there was interference, the result most likely would be that the pilot would see inconsistent readings from his/her instruments and might end up flying the wrong path. The most likely result of that would approach control or departure control would have to reroute other aircraft to avoid the problem while the pilots sort the issue. The effect, then would be limited to messing up the traffic flow in/out of the airport, resulting delays, etc., not a big ball of fire and an impact crater.

jeff

simpler • December 14, 2007 9:20 AM

@Jeff, Isn’t the same true in hospitals.

Yet the maintenance staff and security walk around with much higher power walkie talkies and the doctors use their Blackberries.

MayorCan • December 14, 2007 9:23 AM

Bruce: The stewardess is just giving you permission to use the seat cushion as a flotation device. She is not saying it will work or that you will even need a flotation device. Just that you have her permission to use it as such if you feel the need.

Altotus • December 14, 2007 9:32 AM

Well, I’m sure it’s occurred to the terroristas out there that the security checkpoint itself would be an ideal place to self-detonate. Most airports, security is such a bottleneck that at any given time there may be 4-5 plane-loads of people in the queue (and the queues are typically serpentine in nature, meaning that one could wait until they reach mid-queue to maximize casualties).

Nobody is screened before they approach the screening queue, after all.

Dima • December 14, 2007 9:33 AM

jeff, first of all, TDMA (GSM included) phones do interfere with radio communications (if you have never heard the sound of a GSM control channel exchange in your speakers, you might be an American). And the said exchange is much more likely tio happen on take-off or landing with lots of base stations around. Second of all, see Steveoriino’s explanation about situational awareness. Also, here’s a little blurb from the recently released report on Airfrance’s Airbus mishap in Toronto:

In a second case, a cabin attendant noted that a passenger blocked egress
while retrieving and arranging items in his carry-on baggage. The passenger did not respond to
the attendant’s commands to leave his baggage and go to the emergency exit, nor did he
respond to the angry comments from passengers standing behind him. Consequently, the
attendant had to redirect passengers through the middle bank of seats to the other side of the
aircraft to access the only available emergency exit in the aft cabin.

FP • December 14, 2007 9:49 AM

Heathrow is not barely usable, it just sucks, especially if you’re connecting.

The UK insists that incoming passengers (at least from the mainland) are screened twice at their point of origin (including shoe scans). But because they don’t trust other countries’ checks, they screen you again upon arrival in Heathrow, before you enter the terminal.

Then you have to wait in the main waiting/shopping area staring at the departure screen until your flight is called, at which point 250 people run through narrow hallways and line up outside the gate, where they check your papers and do random carry-on baggage checks.

There’s a waiting area at each gate, but for whatever reason it’s unused. Probably requires less staffing to only open the gate at boarding time.

Even the French at CDG are less annoying.

DaveAronson • December 14, 2007 9:56 AM

Re electronic devices, I can just hear Flanders & Swann now:

Passengers will please refrain
From using iPods while the plane
Is standing on the runway.
I love you!

We encourage being silent
While we’re talking to the pilot.
If the plane can’t go-go
Why should you?

derf • December 14, 2007 10:00 AM

The only reason they’re scanning shoes is because some moron tried to light his shoelaces made of plastic explosives on fire. The easiest way to defeat the shoe scanning system is to place the plastic explosives elsewhere upon your person. Look at the fashion world. Anything that has string or laces can be used, like women’s pants with the laces down the side. Anything that has any sort of filling or compartment could be used – some men’s belts look like they could be created to have a layer of plastic explosive inserted.

But we’ll continue to uselessly harass the flying public while allowing any real threat to pass on by. Thank you, drive through please. Moo.

Roy • December 14, 2007 10:31 AM

The US itself is unable to stop its own madness, but other countries can, if they do it right.

New policy for non-US airports:

First is the passport check. A US passport marks the holder for special screening; all others breeze through, with fervent apologies and best wishes.

Second, for the US passport holders, is a complete strip search, in public, and a cavity search. If no weapons of mass destructions, no contraband, and no containers of more than 3 ounces of fluid are found, the passenger is passed through. Otherwise they are extraordinarily rendered to secret overseas prisons for ‘enthusiastic interrogation’.

When US airlines see their profits nose-dive, there will be a change of heart, and this high-handed heavy-handed nonsense will come to a shrieking stop.

simpler • December 14, 2007 10:32 AM

@JT – It’s ridiculous because there are so many other ways to get the next one on board. How is what they are doing with shoes and liquids going to stop the next one? It’s a bit like building a bank vault with a sand floor or a window.

cdn • December 14, 2007 11:27 AM

It’s been a 1.5 years since I’ve flown. My last flight was from a Canadian city to a US and then a return to Canada.

The flight outbound was uneventful. Return leg though was not.

Before departing I had to clear security at the US airport. I knew I could refuse to take my shoes off, and since I had the time I did. They made me wait in a glass ‘box’ until the lines got sparse. Then they have me sit down and remove my shoes. The lackey unhappily rammed his wand into the shoes (clearly, so he din’t have to touch them and the face was to show his displeasure) and walk them over to the x-ray machine. I appologized to him for the US stupid security measure but went on to say that “I just put on clean socks so I am NOT putting them down on the filthy floor”.

Before the shoes were done he came back and asked me to stand on the foot outline’s so he could wand me. I said “I’ll wait until I have my shoes back, thank you”. I made him wait for me to lace them up and not just slip them on. This is everyone’s duty to get to the American security theatre people to wake up. Irate the hell out of them like they do to us.

Landing at Toronto, many of us had to pass through security before we could get on our connecting flight. It was hilarious to see of the Americans doffing their shoes while the Canadians did not. Anyone standing back and watching back could recognize once who was Canadian and who was a yanky lamb.

cdn • December 14, 2007 11:31 AM

@Roy
Agreed!

We in countries other than the US should also demand that every American provide fingerprints and DNA samples or turn them back. I can see the uproar now – “Don’t you know who we are?”

Yeah, a once unquestionably great nation reduced to a nation of zombies.

J • December 14, 2007 11:33 AM

I and every other other passenger got security scanned after landing on Iceland, when flying from the US. I wonder if there is a real reason, or if they just want to make a statement against the US fingerprinting and shoe scanning.

Anonymous • December 14, 2007 11:36 AM

I bet soon you are only allowed to wear one pair of shoes and not have any in hand luggage OR not wear shoes and have one in your hand luggage.

gregory • December 14, 2007 11:38 AM

ironic how only the countries that know they are doing wrong in the world are the ones with the heavy security… in asia, most of the world, you just get on the plane… i think the security is guilt in action, self-denial…

bithead • December 14, 2007 11:52 AM

Where do you fly? Since they started scanning shoes, I’ve never been allowed through any metal detector with my shoes on, and never had to pass shoes through a separate detector for shoes.

Johnny Anonymous • December 14, 2007 12:01 PM

@Altotus,

When the goal is terror by causing maximum mayhem, security measures just move the target around. I’m surprised that terrorists haven’t hit airport terminals like you say, or for that matter domestic military base gate lines. Maybe it’s because they’ve already accomplished their goals.

Ctrl-D • December 14, 2007 12:06 PM

You haven’t truly been through “Security” until you’ve traveled into Israel via Ben Gurion…

I arrive at +3 hours with my GF who was seeing me off, well within the allotted time for every level of screening, and I barely made my red-eye. I was ‘flagged’ for “further screening” after I answered honestly the initial screener’s questions as to where I had spent my trip. (The GF lives in an Arab neighbourhood in Israel).

After they dumped my bags, I was ushered to a very small room containing three very unfriendly-looking ex-IDF Security managers. I got wanded, and the zipper on my jeans set it off. These guys looked at each other and said, in Hebrew, “What’s that?” I’m like, “WTF? THE ZIPPER??? and things went downhill from there…

Then I was asked, without so much as a ‘by your leave’ to drop trou. After a perfunctory wanding where they put the wand between your thighs, and then quickly and with slight panic at the time, dressing quickly and being escorted out of the Security office.

3+ hours after arriving at Ben Gurion, I am hustled, with no fanfare, through Customs and barely board my flight to the States.

Something has got to change. I appreciate the comments here concerning how to improve Security and helping to build some real cachet back into flying–making it stylish again like it was in the 60’s when air travel was not something ordinary middle-class people did. You know, before the downward spiral of fuel costs and labour demands destroyed the quality of air travel…

At this point, I dread air travel. Flying today is to be treated as chattel. I wish I could afford chartered flight, but those services are still out of my price range.

Elmar • December 14, 2007 12:14 PM

Well believe it or not, I found out this works some weeks ago. I had a single shoe in my notebook bag. (I forgot to put it in my trunk with the other one and didn’t want to open it again for it.)
When I came to the shoe x-ray I put it in and walked through. When a single shoe came out of the machine the operator was confused, looked down at me and saw me wearing shoes. It took him a second to decide what to do: “Please take your shoe, Sir”…

Zathrus • December 14, 2007 12:19 PM

It’s not just Heathrow; flew from Gatwick about 6 weeks ago and it was the same decoupled screening, as well as random selection (most were allowed past; some weren’t). Didn’t seem all that chaotic there, but probably due to the random selection.

A woman near me was randomly selected as well, and she got very upset over it and was asking why she was selected and not someone else. I personally didn’t care — it’s just security theater, and it wasn’t worth starting a fuss before a long flight that was ending a 3 week business trip.

Grumps • December 14, 2007 12:33 PM

To paraphrase a comedian, we’re lucky that Richard Reid didn’t attempt to pass his explosive concealed in a body cavity…

If terrorists had wanted to disrupt air traffic, they couldn’t have come up with anything better than the TSA. It’s annoying enough that people think twice before flying, and inefficient enough that terrorists could still destroy a plane if they could set up the operation. In other words, the TSA is very harmful while doing little to bar terrorists from boarding a plane, except security theater — and the illusion doesn’t hold very long.

Fortunately, there are other factors at play that kept our planes in one piece.

I believe the major reason why we haven’t seen a 9/11 repeat is because most suicidal terrorists are lured into going to Iraq and Afghanistan to fight against US and Allied troops. For example, France recently dismantled a network of wannabe jihadists that was shipping volunteers to Afghanistan. That’s an interesting (and unintended, I’m sure) side effect of these wars.

Enon E Mouse • December 14, 2007 1:04 PM

WRT “Ignore for a moment the ridiculousness of screening shoes in the first place,” I’m inclined to agree with JT (http://www.schneier.com/blog/archives/2007/12/defeating_the_s.html#c224406): When I was a younger man, everyone I knew regularly carried drugs (amounts suitable to personal use) and money in their shoes — including when traveling via plane — because 1) no cop or airport security folks every checked shoes and 2) no mugger ever asked a greasy hippie kid to surrender his threadbare Adidas. Although I hate security theater, I do think that checking shoes does constitute better police work (provided you’re concerned with preventing folks from traveling around with small amounts of drugs — I, personally, could care less, but most polls seem to agree that America thinks we should all Just Say No.)

cosmix • December 14, 2007 2:34 PM

A couple of weeks ago I flew from LHR. The security screening procedure involved taking your shoes off before going through the metal detector, placing them in a box and having your shoes scanned along with your coat, bags etc. I do recall the shoe-scanning device from previous trips, however. Perhaps their procedures have changed recently.

In addition to this, despite the shortages in personnel and the overcrowding I am not so certain the shoe-switching trick would go unnoticed.

mare • December 14, 2007 4:44 PM

Last time I went to Heathrow I didn’t take the connections sign but instead went to arrivals. I had to show my passport, and went straight to departures where I went through security again where the lines were just 5 minutes long. Total time 20 minutes. Two months ago while transferring from plane A to plane B it took me 2 hours and I missed my flight and had to be rescheduled on another carrier and with an extra stop in the US. So I’ll take, this Tuesday going back to Canada , the land-in-the-UK “trick” again.

Karl • December 14, 2007 5:01 PM

An alternative way to smuggle your plastic explosives onto an airplane of course, would be to simply put them in your pocket instead of your shoes.

As you’ve said before Bruce, it’s cover your ass security at its best. No need to think creatively, just give the illusion of security.

Richard • December 14, 2007 8:56 PM

I pointed out the exact same thing to my wife when we flew through Heathrow a few months ago. You could take explosives out of your bag, hide it in your shoes at the bag scanner and then place it back in your bag before you it the shoe scanner. It took me by surprise to walk around the corner and see the shoe security line, but even then I had time to react and could have placed anything back into my bag.

Anonymous • December 15, 2007 3:14 AM

By the way, why in most of the airports, they ask you to take your laptop out of your bag and open it (not necessarily powering it on)?

I just hope the paranoia doesnt get to a point of asking for an endoscopy.

Jay • December 15, 2007 4:10 AM

@Fridz
From an Economist article on Sep 6, 2006 about a fictuous airline with truthful on-board announcements:

“Please switch off all mobile phones, since they can interfere with the aircraft’s navigation systems. At least, that’s what you’ve always been told. The real reason to switch them off is because they interfere with mobile networks on the ground, but somehow that doesn’t sound quite so good. On most flights a few mobile phones are left on by mistake, so if they were really dangerous we would not allow them on board at all, if you think about it. We will have to come clean about this next year, when we introduce in-flight calling across the Veritas fleet. At that point the prospect of taking a cut of the sky-high calling charges will miraculously cause our safety concerns about mobile phones to evaporate.”

MarkF • December 15, 2007 7:53 PM

Bruce, while you can probably read my e-mail, would you mind not reading my mind so much?

I flew from Terminal 3 on Thursday night and what you wrote were exactly my thoughts as I sat, grumbling, unlacing and then relacing my boots…

The guard seemed distracted enough that I could probably have passed two live pigs through the x-ray machine without anyone noticing.

MarkW • December 15, 2007 11:40 PM

Did you notice the lane for people in wheelchairs? Last trip to London I just tailgated behind one and skipped the shoe scan entirely.

caradoc • December 16, 2007 10:49 AM

Since this is all theatre anyway, maybe the best thing would be to have actors taking off their shoes and having them scanned so all the rubes can see them and feel reassured without actually slowing down the process.

Jerome Lacoste • December 16, 2007 1:15 PM

We’re asked to remove the shoes because they are too low to get scanned properly, right ?

What about hiding a blade under the foot, inside the sock, then ?

Shouldn’t we ask people to raise their feet high when they walk through the portal ?

Huge • December 16, 2007 1:22 PM

Shoe scanning? I flew out of Heathrow T3 three weeks ago yesterday and no-one did anything with our shoes. I strode straight through security wearing them throughout. No-one looked at our bag full of 100ml bottles of liquids, either.

csrster • December 17, 2007 2:37 AM

Jonathan,
I was at Tegel last week and the security system wasn’t as you described – it was just one line for the whole departure lounge. Perhaps it varies between terminals?

Although the security at Tegel seemed fairly fast and efficient the guard was the most oddly simultaneously polite and impolite security guard I’ve encountered. He wouldn’t actually let me pass until I’d replied to his “Guten Abend” 🙂 which was pushing my command of German to its absolute limit. I did briefly wonder if he was checking for orally-carried explosives.

Steph • December 17, 2007 4:22 AM

I’ve noticed that most of these practices come from America, or at least this is what the staff would like us to believe. I went to the states (from Heathrow) last year and there seemed to be a serious bout of paranoia at the time. As well as the removing shoes to be x-rayed along with bags and having to prove my electronics worked (which I can somewhat understand, I had enough miscellaneous devices that I see why they would be viewed with suspicion) every flight to the states involved a long line at the gate, the carry on bags being manually searched and every passenger patted down. We were informed that those measures were a requirement for flying into the country.

I like to think that in the UK we would be subjected to nothing more than the regular screening if left to our own devices (bag x-rayed, walking through the scanner) and nothing more. Mostly theater but I can see some benefit there. I imagine it removes impromptu weapons when there may be a spontaneous act of violence e.g. pissed off teenager picking a fight.

Okay, I give the UK too much credit, but it is nice to dream

PaulG • December 17, 2007 6:32 AM

I’ve heard that there’s about a one in a million chance of someone trying to smuggle a bomb on a plane. The chances of TWO people trying to smuggle bombs on is astronomically small.

Thats why I always take my own bomb.

Mike • December 17, 2007 11:36 AM

I think this is an excellent system that actually encourages stupid mistakes. It’s classic misdirection – someone thinks they can fool the system by pulling the above scam, so they might actually try it. Then you have a hidden (but observant) officer watch them perform the switch, and pull them to the side and introduce them to Mr. Full Body Cavity Search.

The point, as has been reiterated on this blog so many times, is not to make the place impermeable. It’s to find the aberrant behaviours. I think this is one place where I can imagine Security Theatre being legitimate.

csrster • December 18, 2007 3:49 AM

Maybe, or maybe the first line of screeners are on the lookout for people carrying an extra pair of shoes in their hand luggage.

Mark • December 18, 2007 7:13 AM

“”It works” as in “we had no exploding shoes on planes so scanning shoes makes sense”..?”

Hmm… So if we introduce a new rule, which obligates airport security to drink a cup of coffee for every passenger coming by, and subsequently no terrorist attacks take place, does this mean that drinking coffee helps prevent terrorist attacks ? ;-Q

Of course the introduction of such a rule doesn’t necessarily proof anything, as it’s not known whether, without the measures, any attack would have taken place.

Also it would imply that any airports without these measures would suffer from terrorist attacks.

DanBeale • December 18, 2007 9:42 AM

“You can’t take your liquid explosive onto the plane. Please leave it on the counter in the small, crowded room. Thanks.”

I used to think that asking people to take their coats and shoes off was about making them bend over, so you could see if they had explosive vests on. That’s been the explosive delivery garment of choice for suicide-bombers for a while now, so it kind of makes sense.

Except no-one looks at you when you’re taking your shoes off. And you don’t have to bend down to remove shoes anyway.

Joseph • December 20, 2007 5:39 AM

The security people at heathrow are so badly formed that they don’t even know that an antique blow lamp(torch) does not have a gas canister. It was terefore confiscated as if it where a dangerous article with a gas tank. I think that after over 50 years of sitting -empty -in a shed, there is no trace of the kerosene left.
Still, there was no way of convincing these buggers.

Anonymous • December 20, 2007 10:19 AM

It’s actually much easier to defeat at terminal 1. The security screening staff have been told that they must scan 1 in every 4 pairs of shoes. There are conveniently 8 scanning machines so at any one time two queues have to remove their shoes and put them through the scanner (just as in the USA) the other 6 queues just walk through the metal detector, so if you want to defeat the scanner don’t get in the queues where they are taking their shoes off……. Defies belief doesn’t it.

On another airport “security” note, I’ve had two experiences in which me or my travelling partner were singled out for “SSSS” screening. While two does not a pattern make, there was one glaring similarity to each trip. In each case the person singled out had booked a USA domestic flight through hotwire or expedia (not directly through an airline) and used the middle initial in the booking. Nothing appeared awry until getting to the ticket counter. The boarding pass printed out in each case had smashed together the first name and the middle initial. For example, a booking for John P. Sousa came out on the boarding pass as “Johnp Sousa.” Clearly the ID (driver’s license or passport) presented was not “Johnp Sousa.” I was told the extra screening was called for because of the name/ID discrepancy. Since these two incidents, from different airports spanning 6 months, I do not book using my middle initial, nor do my friends. We’ve had no problems since.

russ • December 21, 2007 2:18 AM

At an airport in Germany, I saw a much simpler way to defeat security. After walking through the gate and setting off the beeper, they scanned my body and decided my feet were too metalic, so I was asked to take off my shoes, which they examined and found to be safe, so I was free to go. But I could have simply had Forbidden Metal Stuff in my socks.

John David Galt • December 21, 2007 11:40 AM

@Fridz: The rule against using cell phones on an aircraft while airborne has nothing to do with the aircraft’s own safety, or even its communications (and in fact, Canadian small-plane pilots have posted on rec.travel.air that they are directed to use this method to contact some control towers).

The reason for the rule is that every cell phone, when turned on, sends out a periodic “ping” which telephone switches use to determine its location so incoming calls can be routed to it. At high altitude, the phone will register as being present in every cell within line-of-sight of the plane — thus creating chaos on the telephone network.

The aviation industry has been working for several years on technology that would solve this problem by putting a Faraday cage around the passenger cabin of an aircraft, then establishing a cell inside the cabin which would route calls onto the AirPhone network. It was tested earlier this year but still has bugs, and nobody knows if it will ever see the light of day.

jr • December 25, 2007 4:04 PM

Cell phones can and have interfered with aircraft navigational systems. At 40,000 ft cell phones are too far away to connect to base stations on the ground with the 2W max that they can transmit. Also base station antennas are designed to have optimal gain within a few degrees of the horizontal, i.e. distance along the ground. To save battery power cell phones normally connect to a base station with the minimal power needed. If the base station is near, i.e. when in a city for example, the phone can use low power and this extends battery life.

When a cell phone is taken high into the sky the phone cannot connect to a base station, and so it tries to get a connection by increasing its power output until it is transmitting at the maximum 2W to try and get a base connection.

Now imagine a plane with over 100 passengers, all with phones switched on. This total effect will be 100 phones transmitting at full power, constantly searching for a base station to connect to. This can create a large amount of E.M. interference for the planes systems, e.g. 200W+ of transmitting RF power, also interfering with the audio circuits when pilots are trying to talk to traffic control etc.

One or two phones will not have such a dramatic effect.

Note that I have flown a plane below 6,000 ft and have been able to use my cell phone without any problems.

A phone within range of a number of base stations will result in the base stations choosing which has the strongest signal strength and using that one. Its the same as being in a city with a large number of base stations being in range to handle large amounts of cell traffic.

jr • December 25, 2007 4:16 PM

P.S. You can use cell phones on flights at height because a base station that uses a satelllite system has been installed on the plane 🙂

security expert • December 14, 2008 12:48 AM

We are victims of a mass neurosis which forces an unprofessional appearance upon airline passengers at the airports due to a paranoid reaction by the airlines, governments and courts. So many lawyers, doctors and executives have been embarassed that it appears to be originating not only from stupidity, but also from the use of accomplices in trhe form of “checkers” and electronic companies who are profiting from the enforcement of the police-state high-handedness. A job where you have to frisk and disrobe people as some passengers have reported is no job at all, but is an instrumentation of a deranged mentality in the airport managers and airline executives.

Security Expert • December 27, 2008 12:06 AM

When you think of about 2 million people every day going through the steps of removing their shoes in public, it is clear
that the Supreme Court has misinterpreted the law and has used the term “administrative searches” to cover
the ostensive invasion of personal privacy deemed to be “necessary”. The
Airline companies and airport managements are equally responsible for
the miscarriage of justice. Also, the Governors of each State and City Mayors
where airports are located should not look away at the damage this is doing to their reputation and that of their States and Cities. No longer can they be proud of their airports and airline services. Once famous, Kennedy, La Guardia, Dulles, LAX, O’Hare, Miami, Houston, Honolulu and in fact all of them, are names which remind of discomfort and embarrassment, in addition the other problems of long waits, bag checking fees, security taxes, pat-downs, etc.
An arrest has been made of the American People, a type of frisking (disrobing) usually not even legal in arrests by county police, has slipped into the system as a result of a politically motivated reaction which has led to the downfall of professional air travel.

Randall • August 1, 2013 11:43 AM

I’m a big fan of Bruce’s writings, and agree that shoe screening, liquid screening, ID checking, etc. is foolish theater that wastes resources. However, I’m really surprised at this blog post (which I just stumbled on today). As Bruce says in the third paragraph: “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.” OK, so we put the dangerous pair in our carry-on bag which goes through the initial X-ray machine. From the initial assumptions, the dangerous pair will be detected at this first step. Hence, this isn’t a way to defeat the system (given the assumptions).

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