Held for ransom again?

Liquid explosives? I’ll give it the benefit of a doubt, but the jury is still out on that one. It is an attractive theory, but experts seem to throw up some major difficulties making effective explosives on board a plane.

The great difficulty for authorities is that, while they obviously can’t give chapter and verse details, the media and conspiracy theorists will have a field day with the probabilities.

We, the lambs, are left to either accept blindly the word of the shepherd or risk the wolf. Either way the wolf wins this one because it undermines so many of the ‘liberties’ we are led to believe we have.

But what they cannot force us to do, terrorist or ‘upstanding’ politician, is to suspend disbelief or reject consideration of known fact. That is where the suggested liquid explosives becomes a problem.

Of course there are things we are not going to be told, but one of them is not that the clever terrorists have invented a new type of explosive. So here are what the experts have to say about the known:

From the London Times: The liquid explosives that are sufficiently destructive in their own right to blow up a plane are generally too unstable or too easily detected to be readily smuggled aboard.

Many give off a pungent smell, while substances such as nitroglycerin are difficult to transport as they are liable to go off prematurely. Explosives based on nitrogen, including nitroglycerin, can also be detected with a technique called neutron activation analysis, which is used at many airports.

A more subtle approach would be to combine two or more liquids that are stable by themselves, but which form a powerful explosive when mixed together.

A prime candidate for this would be triacetone triperoxide (TATP), the explosive used by the July 7 bombers. Its two raw ingredients are both liquids, which could potentially be carried on board in sufficient quantities in containers such as bottles of shampoo or contact lens solution.

But then the article goes on, this would need to be done in the planes lavatory. The liquid would need to be converted to a dry crystal state. The main suspect, the nitro family all require some kind of detonator device, something which might not easily pass airport security, to set it off.

Prof Hans Michels, an explosives expert in the department of chemical engineering at Imperial College London, said: "Liquid explosives are very, very sensitive and there are many different types, but we could well be talking about nitroglycerine which has been around for many years.

"It is easy to make and you do not need very much. It can be colourless, pale yellow or brown but you can add colour to make it resemble anything you like, such as fizzy drinks or even baby food. Daily Telegraph

Andrea Sella, senior lecturer in chemistry at University College London : “I do wonder though how easy it would be to do in practice. How someone gets up and goes to the loos, with other passengers banging on the door, and does everything right. There would be no guarantee it would work.”

Alternatively there is: methyl nitrate, is unusual in that it will explode as soon as it is combined with another substance. It does not need to be ignited by a detonator device.

"It can reliably be caused to detonate by mixing it with ingredient X," said Dr Alford. He was not willing to reveal the name of the activating chemical. The Independent

For the rest of us it is now a matter of traveling light, foregoing the duty free and letting the madness play itself out. No doubt the whole issue will be analyzed for years to come, until we are all proficient, in knowledge at least, on bomb making.

Meanwhile we will be held to ransom, but I’m not sure who our real captors are yet.