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Heathrow scraps liquid container limit

bbc.com

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Re: Heathrow scraps liquid container limit

#121

Post by HNisCIS »

jandrewrogers wrote: post #71

This just adds confusion as to the purpose of all this. The motivation behind the liquid limits is that there are extremely powerful explosives that are stable water-like liquids. Average people have never heard of them because they aren’t in popular lore. There has never been an industrial or military use, solids are simpler. Nonetheless, these explosives are easily accessible to a knowledgeable chemist like me. The…

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.

Re: Heathrow scraps liquid container limit

#122

Post by boomskats »

contingencies wrote: post #85
jandrewrogers wrote: post #71

This just adds confusion as to the purpose of all this. The motivation behind the liquid limits is that there are extremely powerful explosives that are stable water-like liquids. Average people have never heard of them because they aren’t in popular lore. There has never been an industrial or military use, solids are simpler. Nonetheless, these explosives are easily accessible to a knowledgeable chemist like me. The…

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 transi…

You mean Tony didn't really make £20m in his first year out of office from just giving speeches? I mean, that's what his tax return says?

You, sir, are a _conspiracy theorist_. Don't let that rotating door catch you on the way back in.

Re: Heathrow scraps liquid container limit

#123

Post by aiisjustanif »

edm0nd wrote: post #87
jandrewrogers wrote: post #71

This just adds confusion as to the purpose of all this. The motivation behind the liquid limits is that there are extremely powerful explosives that are stable water-like liquids. Average people have never heard of them because they aren’t in popular lore. There has never been an industrial or military use, solids are simpler. Nonetheless, these explosives are easily accessible to a knowledgeable chemist like me. The…

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…

While still theatre to a degree, that was 11 years ago.

Re: Heathrow scraps liquid container limit

#124

Post by chipsrafferty »

ascorbic wrote: post #104
necovek wrote: post #64

Earlier quoted context omitted.

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…

This might make sense if there weren't shops selling large bottles right after security. Ones full of highly flammable liquids, even.

Like what? Alcohol isn't flammable unless it's over 63%, and you aren't allowed to bring duty free alcohol on the plane.

Re: Heathrow scraps liquid container limit

#125

Post by al_borland »

djtango wrote: post #23
lobochrome wrote: post #16

This rule wasn't enforced anyway... I travel a lot - and never take out any liquids. Have nail clippers and scissors in my carry-on. Once I even had an opinel pocket knife in my laptop bag for a couple of months. Travelled through Tokyo, Taipei, SFO, DEN, PHX, LAX, BOS, JFK, FRA, AMS, MUC, LHR - nobody noticed. I seriously had forgotten it was there, so I don't do that now, but still... Also, no large water bottles o…

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

It would be nice if there was an option to box it up and mail it back home or to a friend/family member for a fee. While a lot of people have throw away knives and wouldn’t care, many also have knives that are either expensive or have a lot of meaning.

Maybe they would encourage more people to risk it and hope they don’t get caught, but a vast majority of these people aren’t criminals. When I was a kid I would always take a Swiss Army knife with me on vacation. That was my favorite thing to back, and I could look like a hero when an opportunity came up where it was useful. No longer.

Re: Heathrow scraps liquid container limit

#126

Post by no_wizard »

abenga wrote: post #111
none2585 wrote: post #90

Earlier quoted context omitted.

This is an asinine take - it literally has nothing to do with the theater we deal with at the airports in America

What's the actual reason then?

Better cooperation between intelligence and law enforcement agencies

Re: Heathrow scraps liquid container limit

#127

Post by mcmoor »

runarberg wrote: post #110
vjvjvjvjghv wrote: post #60

Earlier quoted context omitted.

No hijacked planes, no terror attacks?

I don‘t think that is true at all. There have been numerous hijacked planes since 9/11 including two in the USA just this decade. https://en.wikipedia.org/wiki/List_of_aircraft_hijackings Plane hijacking has been on its way out anyway after the turmoil of the 1970s. And that has probably more to do with a) the relative political stability of the post cold war period, and b) a general sense that airplane hijacking isn…

There has been way less terrorism in general too. I'm always curious whether the war on terrorism is that effective, or there's major socioeconomic factor that matters most (or there's just less lead in the air).

Re: Heathrow scraps liquid container limit

#128

Post by wyldfire »

jandrewrogers wrote: post #106
scq wrote: post #77

Earlier quoted context omitted.

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 am not up-to-date on the bleeding edge but that explanation doesn’t seem correct? The use of x-rays in analytical chemistry is for elemental analysis, not molecular analysis. (There are uses for x-rays in crystallography that but that is unrelated to this application.) At an elemental level, the materials of a suitcase are more or less identical to an explosive. You won’t easily be able to tell them apart with an x…

Here's an article that talks about Dual-energy CT [1]. And another one talking about material discrimination using DECT [2].

[1] https://en.wikipedia.org/wiki/Spectral_imaging_(radiography)

[2] https://pmc.ncbi.nlm.nih.gov/articles/PMC2719491/

Re: Heathrow scraps liquid container limit

#129

Post by jandrewrogers »

chipsrafferty wrote: post #118
jrockway wrote: post #75

Earlier quoted context omitted.

People travel with liquids they don't intend to eat. Shampoo and all that. There is also nothing that precludes explosives from being non-toxic. Presumably your demise is near if you are carrying explosives through security. What do you care about heavy metal poisoning at that point?

But also you can fill up a water bottle after security. Wouldn't it be fairly easy to make a pen or similar innocuous item out of sodium, and drop it in a bottle of water to make an explosion? My point is that security can never be strict enough to catch someone who's truly motivated and funded, without making it impossible to admit people at a reasonable pace, and the current rules don't really help with that except…

FWIW, sodium in water is such a pathetic explosion that it would mostly be an embarrassment for the would-be bomber. It wouldn’t do any meaningful damage.

An explosion with real gravitas is far more difficult to execute than people imagine. (see also: people that think ANFO is a viable explosive) This goes a long way in explaining why truly destructive bombings are rare.

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