Correct. In the US, the TSA is just a government jobs program for the lowly skilled or unskilled. It's all security theater.

TSA Chief Out After Agents Fail 95 Percent of Airport Breach Tests

"In one case, an alarm sounded, but even during a pat-down, the screening officer failed to detect a fake plastic explosive taped to an undercover agent's back. In all, so-called "Red Teams" of Homeland Security agents posing as passengers were able get weapons past TSA agents in 67 out of 70 tests — a 95 percent failure rate, according to agency officials."

https://www.nbcnews.com/news/us-news/investigation-breaches-...

It's about making people feel safe.

We're not rational beings, so what do you do about an irrational fear? You invent a magical thing that protects from that irrational fear.

You're orders of magnitude more likely to die in a road accident, but people don't fear that. They fear terrorist attacks far more.

You can't protect against an opponent who's motivated to learn the inherent vulnerabilities of our systems, many of which can't be protected against due to the laws of physics and practicality - short of forcing everyone to travel naked and strapped in like cattle, with no luggage. And even then, what about the extremist who works for the airline?

So you invent some theater to stop people from panicking (a far more real danger). And that's a perfectly acceptable solution.

These liquids show up as slightly different colors in the new CT scan machines and this can finally be reliably detected by software.

This is also why a bunch of airports no longer ask you to take electronics out of your bags.

> Average people have never heard of them because they aren’t in popular lore.

Everything I know about liquid explosives I learned from Die Hard 3.

most of airport security rests on the notion of going over a series of long tests will elicit unusual (fear, stress) responses from malicious actors and these can then be flagged for even thorougher checks which will then eventually lead to discovery, banning or removal of luggage

so it's not the test accuracy by itself but rather then the fact that these tests are happening at all

> The motivation behind the liquid limits is that there are extremely powerful explosives that are stable water-like liquids.

The limits were instituted after discovering a plot to smuggle acetone and hydrogen peroxide (and ice presumably) on board to make acetone peroxide in the lavatory. TATP is not a liquid and it is not stable.

https://en.wikipedia.org/wiki/2006_transatlantic_aircraft_pl...

From my understanding, the new CT machines are able to characterise material composition using dual-energy X-ray, and this is how they were able to relax the rules.

I thought the point of replacing all the xray scanners with CT scanners was to be able to detect this sort of thing?

Won't asking people to take a swig solve a bunch of those issues?

So how does that explain I can take 10 100ml bottles and an empty 1l bottle through security but not 1 full 1l bottle?

> . This reminds me of the chemical swipes done on your bags to detect explosives. Those swipes can only detect a narrow set of explosive chemistries and everyone knows it.

Meanwhile, you get swabbed, the machine produces a false positive, the TSA drone asks you why the machine is showing a positive, you have no fucking idea why, and they just keep swabbing until they get a green light and everyone moves on with life.

The security theatre is there to make people feel safe.

It's about emotion not logic.

OP is talking about (mostly) TATP here. It's very easy to make, harder to detect with traditional methods and potent enough to be a problem. It's also hilariously unstable, will absolutely kill you before you achieve terrorism, and if you ask people on the appropriate chemistry subreddits how to make it you'll be ridiculed for days.

> Everyone, including the bad guys, knows all of this.

Then satisfy our curiosity and provide more details as to which are the liquid explosives and which common ones are not detected ? ;)

I wonder if the improvements can detect trigger mechanisms better rather than testing the liquid itself.

> It would be great if governments were more explicit about precisely what all of this theater is intended to prevent.

Have you considered just going long Palantir?

there's nothing to really understand

It's obvious. The harder you make it to down or hijack a plane, the fewer downed planes you will see. It didn't have to be perfect to prevent and deter. Some security is better than no security. If you had no security at all you would see planes go down all the time.

And it wouldn't surprise me if some of the detection technology were classified.

It would not be "great" if governments were more open about their detection capabilities; that would cause more terrorism attempts and is one of the stupidest things one could do here.

Security theatre.

And speaking of theatre in the air, most Indian airlines will make an announcement of turbulence just before food service starts.

This is to make the sheep - strike that - passengers go back to their seats and sit down.

Ahh, the naïvety of the scientific mind! The security theater is intended to prevent government beaurocrats' mates from having to get real jobs and keep them happily sponging off public money. Also, set themselves up for post-career high paid gigs with those same private sector beneficiaries, so they can't be done for corruption during their career. Yes, really. Ask an AI about mid to late career public sector transitions to private sector and cross-examine 100 top examples across markets perceived as 'low corruption index'.

There's a whole ton of people taking about MRI -- MRIs are a completely universe than CT/X-rays

Dual energy x ray has been around forever though, like decades.

No successful terrorist attacks on planes going to/from western countries after 9/11/2001, that's a pretty good record. Maybe we can't prove that the security theater was responsible for that, but still, the only planes that were bombed after 9/11/2001 were inside Russia or going from Egypt to Russia.

Depends who the 'we' is. It worked out great for the airports; increased drink sales means increased rent for airport shops.

No hijacked planes, no terror attacks?

3-1-1 is rarely enforced. I always got confused why the 100ml limit existed, since I could just take multiple bottles of 100ml of whatever I wanted and it was okay. Then I realized that technically I only could take 3 bottles but I’ve been getting away with more for decades.

Yeah, I flew thru Eindhoven Airport in the Netherlands a few years ago, and I couldn't believe they let me through with water.

The security used something I would describe as out of an Iron Man film, they were zooming around a translucent 3D view of my backpack. (It was on an LCD display instead of hovering midair, but I was still impressed. But the fact they let me keep the water was even more amazing, hahah.)

> Not because of a sudden outbreak of sanity, but because they have CT scanners now.

What's is the evidence for believing so strongly that airports all over the world have been prohibiting large amounts of liquids due to widespread insanity?

I would say just as if not more important are probably some advanced nitrates detector.

Dublin has been relaxing their restrictions for a while now, and when I travelled two weeks ago, had also completely dropped the rules. You no longer need to remove liquids or electronics from bags, and the liquids per bottle limits are much higher (don’t remember exactly, maybe 2 litres) with no restriction on total number of bottles.

I watched a YouTube video about it a few months back and apparently the new devices, at least those used in Dublin, are much more accurate in detecting the difference between materials that previously looked similar to the machines, they can also rotate the images in 3d to get a look from different angles. Both of these make it easier to tell whether a substance is dangerous, apparently.

I believe the article mentioned density as well. I suspect that is extremely key in determining what it is, or at least determining if it is something really odd that should get additional screening.

When you don't know much about a topic, probability is higher that your are missing some piece than some entity doing things that make no sense.

I know it's easy to get the impression that's not the case. But when your stop making fun of / belittle such events / persons / decision and be curious instead you start to realize that more often than not you are just missing a piece of information.

The truth oftentimes is just not interesting enough and not clickbait worthy.

It's not just large amounts of liquids: it was my understanding that this is both a restriction on large amounts of liquid, but particularly on large containers needed for an explosive of sufficient destructive power.

You could always easily work around the liquid amount restriction (multiple containers over multiple people), but if you still need a large container, it becomes harder.

I don't know if this is true or if a resealable plastic bag also works, for instance (that would be funny, wouldn't it?).

Have you never been screened where they swab your items and stick it in a machine? That is to detect explosives. They can use the first machine to target people for follow up screening.

How did they force you to do that?

Why did you allow them to humiliate you like this?

> My real anger is that we have found it possible to fund and implement this level of screening, at massive monetary, human and privacy cost, but I can't go to my doctor and ... get a body scan that does all the 3d segmentation, recognition, etc

Airport screening of people doesn't yield those results. It's able to notice a big inorganic mass, or a chunk of metal, but it wouldn't spot a tumour, it gives nowhere near the level of detail that an MRI or CAT scan will give. The airport scanners are also much cheaper, coming in at ~250k USD rather than ~2m USD.

Even the xray machines used for bags, while expensive and capable, are designed to differentiate metals, liquids, and organics, not organics from other organics.

Both airport security and healthcare funding have their issues, but I don't think this is one of them.

> My real anger at airport screening is that we have found it possible to fund and implement this level of screening, at massive monetary, human and privacy cost, but I can't go to my doctor and for a few pennies (sorry, those don't exist now, how about for a few nickles?) get a body scan that does all the 3d segmentation, recognition, etc etc etc. We could actually save lives

This always strikes me as a weird thing tech people believe about medicine. Full body scans just aren’t medically useful for otherwise healthy people. You’ll inevitably see something and it’s almost certainly going to be benign but might send you down the path of a lot of expensive and dangerous treatments or exploratory procedures. This is why there’s always so much debate about prostrate exam and breast exam age recommendations. There’s a tipping point where the risk of iatrogenesis outward the risk of disease.

There’s alot to imaging. When my wife was battling cancer she was getting alot of MRIs and was in a trial for computerized radiology. We got to talk to the radiologist, who showed us the difference between what he found vs the machine. The machine spotted some stuff that he didn’t, but wasn’t as good at classification.

You also need context to appropriately interpret what you see.

Only in the Apple reality distortion field would I see the hubris of boot times being equated to saving lives. I see value in saving time, but without the celebrity worship, it's nowhere near the same in terms of importance, application, or utility. Besides, the same time saving desire has been a driving force in software by nameless developers since the beginning of software. Attempting to frame and attribute the concept to a single individual is dismissive and disrespectful to the work of others.

> a few pennies (sorry, those don't exist now, how about for a few nickles?)

Wait what? https://en.wikipedia.org/wiki/Penny_(United_States_coin)

I almost exclusively take trains now because the experience of flying is one of repeated dehumanization, especially in the USA.

First, if getting dropped off in a car (most American airports this is your only option), you must suffer being screamed at by traffic cops while trying to navigate a perpetually under construction dropoff area. You get one (1) peck on the cheek from mum before some uniformed individual waddles over to yell at you some more.

Then you must wait in line at a check in counter behind fifty families with 4 large luggage items each, despite the fact that you only have a backpack. Why? Because when you tried to do online check-in and boarding pass, the site broke / said no, and the self-service check-in kiosk at the airport still isn't switched on despite being installed a decade ago.

At the check-in counter, a person who knows less than you about the country you're traveling to will inform you as a matter of fact that you can't get ok the flight until you buy a return ticket, since that's what their binder says and they don't understand your visa. You must wait for a supervisor to come and verify that your visa is actually valid.

Before security, you're offered the rich person line if you have the money to pay for it. Literally advertised as a "white glove experience." If not well, into security with the rest of the cattle.

At security, you get to be screamed at by TSA for not knowing the exact procedures of this airport you've never been to. Why must they have to tell Passenger, who is one person they see ten thousand times a day, over and over again that you have to push your box onto the automated belt yourself, rather than let it be pushed on as a train with the other boxes. Passenger must be stupid. Surely it's not because of poor signage that Passenger doesn't know what to do. And by the way, take off your shoes and let us look at your genitals. Oh, you don't want us to look at your genitals? Well then we'll have to just grope every inch of your body, and nut check you for making us do our job in a slightly more annoying way. Just in case you're terrorist scum, we'll check if you have bomb making residue on your skin, while someone else opens your luggage and digs around in it so everyone else in like can see what your underwear looks like. At TSA we offer full service sexualized humiliation, guaranteed!

The dehumanization never ends. Once on the flight you are packed in like cattle, so tight you're rubbing shoulders with the person on your right and left, while your knees dig into the back of the person in front of you. You're served a tray of slop that you have to pay for now. Security took your water bottle, but when you ask for water on the flight, it's given to you in a tiny plastic cup, that's free if you're lucky. Now sit there quietly while we try to sell credit cards to this captured audience.

Finally you land and it's time to get off the plane! Oh actually no, the curtain is closed in your face. Silly peasant, you must watch the first class passengers leisurely pack their things and stroll off the plane. Only until the last one is off may the dirty peasants pass the fabric barrier.

If you come in from a country that doesn’t fall under the TSA, you have to clear TSA before getting on a flight that does.

The worst I had was in India, flying to the US. Not only was there the normal airport security (despite having come in on a connecting flight from within India), but when I got to the gate (with only minutes to spare), there was a whole TSA check at the gate itself. Bags x-rayed (again), metal detectors (again), guy with a wand (again), the whole deal. Just getting to the gate, I had to show my papers to at least 6 people; every time I turned down a new hallway. That was my far my worst airport experience.

Pretty common to have to re-clear security at large airports if you've come from another country, I've had to do it every time when transiting through Dubai for instance.

It's super frustrating losing the contents of your water bottle and then having nowhere at all that you can refill it.

I noticed my eyes started automatically skimming right after that paragraph. It's funny my brain has learned to calibrate its reading effort in response to how much perceived effort went into writing it.

I don't even know what I need to show at at the start of the line. My ID? My boarding pass? Both?

A trick I use to bypass the liquid restriction is to intentionally pack a sacrificial bottle in addition to whatever valuable bottle I care about. In most cases when the luggage comes for manual inspection they toss the first (sacrificial one) they see and leave the actual valuable bottle alone.

I'm sure that going through security 5 times for the same flight is bound to trigger some extra screening and even if it doesn't, each time you cross through increases the likelihood of getting caught by the normal process.

Don't get me wrong, I'm sure a large part of it is just security theatre, but part of it is also just to be enough of a deterrent that a would-be terrorist chooses a different target.

> An arbitrary limit like 100ml is pointless

Do you know that the 100 ml liquids gets scanned in the Heathrow airport? Many times they used to do a secondary scan too after the primary scan. I recall this very well because many times I was made to wait longer after my carry on arrived because they wanted to put the liquids through a secondary scan.

Oh. So it was a security measure? I honestly thought it was a way to force you to spend money on things on the airport or abroad. Like shampoo, water, etc.

How about an undetermined adversary? Security is all about raising the cost of an attack, not about preventing one altogether

In many countries (Canada included) if you pass through security into the international terminal, you have to 're-enter the country' back through customs and immigration if you don't get on your flight.

It's also hilarious that the limit is the very metric 100ml, and not some even number of freedom units like 3 or 4 fluid ounces, like Jesus, George Washington, and bald eagles would have wanted.

Hmm, I once transited in Heathrow in a return flight from europe to the US and had to go through Heathrow security for whatever reason, where they subjected me to liquids rules way stricter than either my source or destination did.

E.g. 1 day use contact lenses and prescription creams all having to fit in a tiny plastic bag. So I'm happy for this change.

It’s slowly happening at least in Europe: https://www.skycop.com/news/passenger-rights/airports-liquid...

You know they don't take your liquids at the destination airport, right?

You're already allowed to refill large water bottles from a water fountain after passing through security, so the situation you described is already allowed to happen.

Well you wouldn't want a thirsty terrorist, would you?

We flew a couple legs on Virgin Atlantic yesterday. The info session before takeoff made several mentions of batteries - unplug devices when not on use / not in your seat, if your battery gets hot, don't leave your seat/notify a flight attendant immediately. (I think they have containers to try to contain lithium fires onboard FWIW.)

Recently flew through china where they asked 3 times if if i had a portable charger and made everyone sign declarations to that effect.

If batteries were standardized and replaceable I bet they would force you to not bring your own, and only ones purchasable passed the gate could be used. Maybe that a silver lining to the repairability issues.

south Korean airlines are banning battery use in flight now https://www.timeout.com/asia/news/psa-major-south-korean-air...

other asian carriers will say they can't be in overhead compartments

When gate-checking carryon bags, staff told passengers to take batteries out of the carryons.

It seems like something that is high risk during flight shouldn't be left to passenger compliance with spoken instructions.

I lost a nice swiss army knife in Singapore because I was carry-on only and forgot I keep one in my toiletries bag. Was really upset because it was a Christmas gift from my parents. Annoying they don't let you collect it on the way back, I totally get it but would have paid a fine to get it back

Enforcement is very inconsistent that’s for sure. The system is as secure as the least secure airport.