The only reason to be particularly concerned with them is that they could contain high strength peroxide. I'm not, but I think that anyone trying to synthesize TATP in an aircraft lav wouldn't have much luck.

Well, thanks, but reading all that stuff made me more concerned than I was before. I agree with you that the binary explosives seem difficult to create on-board.

I would therefore be more concerned about nitroglycerin. Relatively easy to synthesize, from readily available ingredients. Can be distilled beforehand, not produced onboard. Very unstable (so it might cause problems going through security, etc.), UNLESS cooled sufficiently (like kept in an ice cooler with some dry ice). And very powerful explosive qualities.

Its detonation qualities, from what I read, would seem to require a blasting cap or some other form of ignition, rather than just an electric charge into a container of liquid. But, it will probably be harder to find the cap or detonation device in a screening search, than it would to locate the liquid.

Nitroglycerin also avoids the scrutiny that taking the mixing utensils, ice, etc. to the lavatory will cause, as well as the extended time necessary to create the binary explosive. I don't know what the stuff smells like, but I doubt it would need to be exposed very long, so the smell is unlikely to be a giveaway.

So, that's the one that worries me the most. They tried it on PAL flight, with the nitro disguised in a contact lens solution bottle.

IIRC, a chem professor said in class once that hydrogen peroxide can generally only get to a 30% concentration before it starts getting really unstable. It is VERY difficult to have a higher concentration without more extreme methods of containment.

If the TSA used available screening technologies (ETD swab, puffer...) nitroglycerin wouldn't be a problem.

Not only is H2O2 above 30% very unstable, but TATP itself is less stable than nitroglycerine and is much more hazardous to make. Would-be terrorists trying to make some in the lav with a bucket of ice, high-concentrations of acetone and peroxide, and a touch of sulfuric acid would be much more likely to blow the stuff up prematurely, which would only main / kill them as the process would be incomplete.

I also just don't know how realistic terrorists making TATP aboard a plane would be (same for nitroglycerine, really). For so many explosives, it's critical to hold the temperature at the right level during nitration so that esterization proceeds at a reasonable rate--too low and the explosive is fairly useless, and too high and it explosively decomposes before completion.

Guys, I'm not "getting" the dire threat here if it's that complicated?

Is turbulence a factor also? Could they end up maiming themselves if the aircraft rolls?

They would indeed be better off synthesizing it and carrying it onboard, as the synthesis isn't super-easy to do correctly (I did it many years ago once in very small quantity). The problems are temperature control: too low, and the nitration doesn't occur rapidly or thoroughly enough to result in a good explosive; too high, and the mixture prematurely detonates.

Of course, ETD will catch nitroglycerine, and from anecdotal reports, will also alarm on most nitrates in general (and thus on the requisite nitric acid) and on glycerine. So we either need to be more vigilant with ETD or introduce similar but quicker screening (puffers, handheld "sniffers," etc.) on a larger scale to ensure it doesn't get aboard.

The components aren't going to be easy to get onboard, either, which is one thing that surprises me about the reports continuing to insist nitroglycerine was a probable explosive in this case. We're talking nearly-pure nitric acid and sulfuric acid. The nitric acid they'd have access to fumes much moreso than what's used in commercial explosive synthesis; red-fuming nitric has small amounts of nitrogen oxides in it, which smell AWFUL and some of which are visible as red vapor.

I'm actually thinking that if this was indeed a fairly well-along plot, they were aiming for something other than nitroglycerine. Even with concealed-bottom beverage containers to hold the acids, it would be tough to get them onboard, mix them properly without being noticed, etc. I'm at a loss as to what, however, would get past ETD if so subjected and would be easily made onboard the plane. Commercial binary explosives would alarm the ETD as far as I can tell, and they'd favor something homecooked due to acquisition problems, I'd think.

That "might" be right, but:

1. How much is it going to bog the line down if we have to use the puffer on everyone (or everyone who carries any container on board), and the ETD swab, and then wait for the analysis?

2. NY Times article suggests that puffer won't work for a really careful terrorist, who eliminates trace amounts. And ETD only works if you swab the right thing. EVERY contact lens solution bottle? Every water bottle? Gonna take some time.

The whole point of the puffer is that you won't need the swab. Puffers didn't add very much time at all. By the time you factor in shoe removal in the other lines, it was probably about equal.

Nothing we do will work on a very careful terrorist. There is always some other hole that they can get thru. You should read MSY-MSP's thought. He's also a lawyer and has them well articulated.

We'd need more puffers, yes. I'd like to see more handheld "sniffers," personally, or putting bags through a puffer themselves. These aren't going to show up overnight, unfortunately.


From what I understand of the puffers and ETD, it would take a pretty determined and careful terrorist to eliminate the trace amounts from the outsides of the containers, from their bodies, from the bags, etc.

As for the volume question, the answer is fairly simple. Encourage pax to check larger (above 4 oz) containers and to not bring beverages past the checkpoint (but don't prohibit it). If you bring those through--and they're already X-raying to see that you don't--you join an ETD line and get to wait longer. Inconvenient, but not so much so as the total ban we have now. And I doubt most people would bring more than a bottle of water and perhaps one or two toiletry items to be swabbed.

What are you worried about? They catch that one very easily when they swab. I know of a lady who got stopped from traveling because her sister loaned her a bag and the sister works in a fireworks factory. Tests for nitroglycerine and products are, I thought, very very sensitive if not oversensitive -- urban legend has them giving false positives to ladies who use hand lotions that contain glycerin.

By the way my story has a happy ending, as the lady traveled after 911 but a couple of years before 8/10 -- they did search all of her bags but after questioning they determined that the problem was undoubtedly caused by her contact with her sister and the sister's bag and they did allow her to fly.

That's no urban legend. It's happened to iluv2fly.

Ways a terrorist could smuggle stuff on a plane that is not addressed by any sort of security measures:

- Contraband can be smuggled onboard undetected in any number of body cavities
- Airport grounds are basically unpatrolled. It would be easy to get something on a plane without going through terminal security at all.
- There's the explosives not detected by xrays thing
- I keep wondering why someone just doesn't bring on a vial of cesium that they break and drop down the lav toilet. Seems to me that would make a pretty good bang. There could be plenty of ways to conceal it or package it so that it's not suspicious. I would imagine it could not be detected by dogs.
- Cleaning supplies still sit unattended on custodian carts past security, including chlorine and amonia-based products.
- Did I mention we all have several viable body cavities?

Ways the security policies are ludicrously inconsistent and meaningless:

- Sharp and pointy objects are banned from carryon luggage, but the first class cabin still serves food and drinks on glass plates, and glass stemware.
- Weapons can be made out of countless items permitted through security, including cords, musical instruments, tin can lids, etc
- There are other mass transportation vehicles that could cause as much or greater damage than planes that don't have TSA security. These include cruise ships, buses, trains, subways, ferries, etc


Conclusion: The current measures only inconvenience the law-abiding and only cause the bad guys to work incrementally harder and be slightly more innovative in their schemes. It does nothing to prevent someone who is motivated from carrying out an act of terroristic malice.

We could say that the situation is analogous to gun control: the only people who will abide by the regulations are the innocent. In the case of using mass transit to kill people, the only ones who will be stopped from bringing explosives, weapons, etc onto a plane are those who wouldn't do it to begin with.

In the above post, I forgot to mention the whole thing about cargo not being screened.

Yet another reason why the security procedures are pointless.

Nitroglycerin is nitrate-based. It's going to be picked up by the ETD gadget.

It's also rather unstable, you could no doubt set it off by hitting it with something.