Monday, November 01, 2010

Early Thoughts on the Latest Bomb Scare

I've held back from commenting on the printer-cartridge bombs apparently from Yemen after I had a Twitter exchange with a blogfriend the first day. The information kept changing and seemed internally contradictory or flawed in some way. Most of the time, it wasn't possible to determine whether the flaws arose from the general confusion surrounding a potentially big breaking story, investigator incompetence, official secrecy, or reporter incompetence. I'm willing to believe that all of those had some effect.

Some of those flaws persist, so it's not possible to draw conclusions beyond that it won't be possible to bring printer cartridges on an airplane for the rest of time. So I'll point up some of the flaws and my questions.

Today's meme seems to be that the bombs were designed to explode in flight (WaPo, LA Times, Boston Globe). How do they know this? Unanimously, they quote British Prime Minister David Cameron, who simply stated that they were.

Now, if the reporters were sharp, they would know that there are several ways to make sure a bomb detonates on a plane: a pressure sensor to detonate at a given pressure, a timer set for a time when the plane is likely to be in the air, or a cellphone chip. All of these don't quite fit the facts given out so far for a conclusion that the bombs were to detonate in flight. The cellphone chip has been mentioned as a component in most reports; I believe I've seen a timer mentioned in early reports, but its popularity seems to be waning. I'm not aware that anyone has mentioned a pressure sensor.

In any case, a pressure sensor seems unlikely.
One of the bombs traveled on two passenger planes within the Middle East before arriving in Dubai. (Boston Globe; also WaPo)
That means that the pressure to signal detonation would have been reached on those flights. Of course, it's possible the detonator didn't work.

The perpetrators need a lot of information to set a timer properly, and even that may well fail:
...with these freight flights sometimes the routing can change at the last moment so it is difficult for those who are planning the detonation to know exactly where – if it is detonated to a time, for example – exactly where the aircraft will be... (Guardian)
A cellphone detonator would need to be in range.

One other clue:
The preliminary conclusion that the devices were designed to detonate aboard aircraft, and not at the addresses in the Chicago area, is based in part on the fact that the parcels were not rigged to explode upon opening. (WaPo)
In any case, why bring down a cargo plane? The greatest reaction comes from the many lives lost.

Of course, it could be that the bomb designer/maker didn't think all this out and thus was not as "professional" as is being reported.

Unfortunately, the reporters don't seem to know much about bombs. The explosive, PETN, is pentaerythritol tetranitrate, not trinitrate, as was reported in many places over the weekend and persists into the Boston Globe account I've linked. It appears that copying is easier than checking. The error may have originated with an official source, but, because the reporters didn't catch it, it's not possible to tell whether that source misspoke or had other things wrong. And, although it's a small error, it raises the question of how well the reporters are doing on conveying other information.

I also find the statements (in multiple places) that PETN can't be detected by dogs or standard airport procedures puzzling. I don't know what dogs can detect, but I thought that those swipe things were put into a mass spectrometer that should be able to detect PETN. Does this mean that the chemically related nitroglycerine can't be detected, either? That puts a new face on the otherwise ridiculous liquid limitations.


Russ Wellen said...

I'm also unclear as to what would keep it from detonating until it got to its destination (if, instead, that was the intention) as well as what would make it detonate upon reaching said destination.

Peter said...

Is anyone asking if this might just be a test-run?.. That is, you install components that will be used in the 'real' exercise, but not configured correctly. You'll see what the target's defenses are like, and where you need to Adapt, Adopt, or Improve (to borrow a phrase).

And with the [suspiciously public] news today about the tipster, there's also the added benefit of weeding out any moles.

Anyway, I'm just indulging my inner CT.

Cheryl Rofer said...

All possible, Peter. Or one of my weekend tweets was a speculation that there were some real bombs and some fakes in various shipments.

A counter to the idea of a test-run is that too much information becomes available to thwart the real thing. Of course, this could have been a test run gone bad.

But there's not enough information to support any of these speculations.

lec said...

I don't follow the test run idea. If the payload was expensive, then it would be undesirable to waste it on a run that may not succeed. But, is that the case here ? Why not just send the explosive out and see what happens ?

Peter said...

Is PETN expensive? I read somewhere that it's not too difficult to obtain, which would make me think it's not too pricey.

lec said...

The PETN was included with the bombs. I don't know what was left out or why anything would have been left out unless there was some great cost to it. What would have constituted a successful trial run ? If you wanted to kill me would you start with a trial run where there is no bullet in the gun ? Why not just use a bullet the first time ? What could the criminal have been trialing ? Maybe I don't get it because I'm not an evil mastermind, but I assume the trial run story can be interpreted as law enforcement stating : you didn't blow up today but you may tomorrow so continue to give us money and your liberty.

MT said...

Squandering materials and revealing methods doesn't amount to disclosing one's target or objective. You can be particular about who you kill and what you destroy and yet still be a terrorist, I'd imagine. Somebody once said this is war, I believe.

Schenck said...

What would a successful 'trial' run even look like anyway? You send a working or near working bomb to a test address, and if it gets through undetected, what happens? The package arrives, and someone is like 'oh, a new printer' and that's it?
How would you know it works?
Why would you ever build a 'near bomb', including the explosives, and mail it out without it being able to detonate? Why not simply include a detonator, let the 'test' be if a plane does or does not go down.

As far as officials messing up on PETN and reporters just copying it, it's even more ridiculous when you consider that the only time they'd use the full name is the one time in the article when they are explaining what PETN stands for; the whole point there is to get it right.