Schneier on Security

DC • December 29, 2009 12:12 PM

A slight quibble here. I do work with explosives, and of the nicely powerful fast-detonating high explosives PETN is by far the easiest to detonate if you leave out nitroglycerin and nitroglycol. Petn is a related ester that happens to be solid, and has a higher det speed (over 7 km/sec) for better shock production. It doesn’t have a lot of heaving power (gas production) compared to other choices like dynamite — it breaks things rather than throwing them a long way. This is one reason it’s a major component in primacord — reliable easy detonation, and a reason the military doesn’t use it for a lot of things — even a pistol bullet would set it off easily with high order detonation. You wouldn’t want to go into battle with a guy carrying a satchel charge that would kill you all were he hit — our military doubtless does some dumb things, but this isn’t one of them. Yes, it does take a blasting cap (unlikely you’ll get enough shock with black powder unless that is very well packaged — see Nobel) but that is not rocket science tech. Nor is a metal-free blasting cap that can be activated chemically with nothing more than a squeeze (see Firefly in the old OSS manuals, from WWII — potassium permanganate and a pill capsule of glycerin is a great way to start a fire that can then set off a blasting cap, you can even control the delay fairly well). And it can easily fit in a pocket and look like a nasty used hanky. Doesn’t have to be seen to be squeezed.

If you don’t believe this, read any good tome on high explosives. Or go get samples of the various ones and try hitting small samples with a hammer on an anvil (actually, a mechanized version of this test is a standard in the explosives development business, called the drop test). You’ll find that petn only takes a tap to detonate — almost no harder than the weaker primary explosive mercury fulminate, TNT takes a good hard swing, and the current plastics (HMX, RDX) take a really hard swing. Most of them are easier to detonate this way than black powder, actually (but the black is insanely static sensitive and flammable). Really, go get some smokeless pistol powder and some black, put a little on an anvil and try this — it’s easy and you’ll learn something.

What it looks like this guy was trying to do, luckily without success is to make petn with nitric acid and pentaerthyrite, hoping that the heat released during the room temperature nitration (this is a lot of heat, I’ve made the stuff, and you melt a lot of ice to do it safely — not a concern if you want it to go off, of course) would cause it to detonate, but instead, it simply burst into flame — the 100% nitric most use to make this would have made his pants flame anyway, most likely. Which by the way, you can do with already made PETN and unless the quantity is large, it will just burn peacefully like a pile of smokeless gunpowder would. It’s pretty, we’ve used it for party tricks.

Would the stated 80 or so grams have taken out the plane? Having used this stuff to break rocks etc, the answer is “maybe, maybe not” — this is not a lot of explosive unless it’s placed just so, perhaps in a shaped charge and with all the stars aligned right. Sure it would have killed the guy, and perhaps a couple other people close by, injured a few more, probably knocked a foot sized hole in the plane, but really — planes can take that more often than not.

You’d have thought someone would have tried this “at home” before the real run and found out how unlikely it was to actually work. Or as stated above, maybe they didn’t care — it had the desired effect even not working as presumably intended.

The only thing keeping us safe from those types is how stupid they seem to be, not the TSA, which seems to match them in the low IQ contest. We’re watching a race to the bottom here.

If I can’t drive there (more dangerous, but in that case I can control most of the risks, and feel better, even if it is irrational) I’m not going.

Were I subjected to the complete loss of liberty in a way I couldn’t ignore, I’d have to face the fact that I too am an idiot to continue to live here and contribute work and taxes to this mess. Too bad this is nearly worldwide — the number of good places to go is getting smaller all the time. I do admit to a bias for places where my native language is spoken.

DC • December 29, 2009 3:36 PM

@Grinch
Thanks. Haven’t been on a cruise ship for awhile, that’s one thing that would take a VERY long drive for me to get to, and I frankly miss it. But the last couple of times I was extremely impressed at their security indeed – well before 9/11. Seemed like it might even beat the Israeli stuff everyone goes on about, but was quite transparent and unobtrusive. (this was on Carnival, BTW).

You are parted from your baggage before boarding, and it’s all throughly checked, X rayed and opened by people who themselves are at risk if they miss something, but not in your sight, so you don’t notice unless you’re paying attention to things like that. You don’t notice unless you’ve put telltales in your bags — they are just in your room when you get there, all the wrinkles are intact. Whoever they have doing these things, they’re real pros, not underpaid jerks.

Everything and everyone going on or off the boat has this done at every stop, no exceptions. You can’t even sneak a Cuban cigar on board unless you change the wrapper with a non Cuban type — I tried and was only successful on the second try.

You are issued a hard to forge picture/hologram ID card you WILL keep on you because you can’t get a drink without it (and any costs put on it come off your credit card automatically so you don’t want to lose it), or get back on the ship, for which they have provisions so in the case of losing it in some foreign country, you can still get back on instead of sitting in the local hoosegow as an illegal immigrant, but it’s not fun at all — so it doesn’t happen much. You have to really validate yourself to get back on, and that can be hard indeed if you’ve lost a wallet or similar.

For example, it’s good to remember the names of your room servants so they can say, yeah, that’s the same guy who got off the boat, stuff like that, or have a pal in the US embassy, which probably means missing the boat altogether and having to find your own way home later.

As they go to a lot of places where people try to sneak into the US from, they’ve seen all the tricks, and have effective counters to them all. An identical twin might foil their system, but the other one would have to stay behind.

Your bags are parted from you again when you get home — and checked for anything that would disturb US customs. I know this as I’ve seen them approach people and offer to save them from being hassled because they knew they had something customs would get upset about and likely find, because they found it first. Quite impressive.

And it’s all done almost so you wouldn’t notice unless you’re looking for it, all smiles and have a great day….and they mean it or are the best fakers I’ve ever seen. Their job description is “create the most fun possible” which of course includes not having the boat used for smuggling or blowing up and so on. And they take it very seriously as one incident and boom go all their nice profits…which are better than the airlines, so they have something to lose.

Our guess (I took my employees on a cruise) is that they employ a goodly number of practical psychologists, some of whom masquerade as your room servants. There is no other explanation for how quickly they size people up and direct them to the most fun for that individual, and spot and neutralize any troublemakers so easily and quickly. I have never seen an outfit so well run (from the customer point of view anyway). My conversations with off duty employees say the same.

If airlines were like that, I’d love flying again, but frankly, commercial big airlines were never that much fun. I like small planes where I have the illusion that if something went wrong, I could fly the thing myself. And for whatever reason, the subjective experience of this engineer says the smaller planes have a LOT more power to weight and various other safety margins. Compared to the puddle jumpers, the big airliners seem made of cardboard and seem to barely be able to fly at all. The end of that runway always seems awfully close before rotation in a bigger plane, where the little guys just jump into the sky. Same idea on landings.