Schneier on Security

Roger • December 9, 2005 10:30 PM

Liquid metal (specifically, aluminium alloy) embrittlement agents do exist, have been discussed in the open literature (including safety posters at airports!) and are already on the list of things prohibited from aircraft — and have been for many years, in fact long before Liddy wrote that article. The main concern is accidental leakage rather than terrorism. As a form of terrorism (rather than industrial sabotage) it’s a non-starter, because the aircraft failure occurs long after application, so even the attacker doesn’t know if he was actually responsible.

The Magic Marker would not be a particularly effective way to apply it. The material has to come in direct contact with structurally significant aluminium alloy components, and there is no such access from within the cabin. Conceivably you could attack unpainted doors while standing in a jetway, but I suspect people would object.

The rest of his scenarios are interesting, although they could not be undertaken on such a scale by any known terrorist group; it would have to be a Spetsnaz operation as a prelude to war, as he suggests.

His suggested threat on EHV tranformers seems to be basically accurate. Liddy didn’t notice it first (it seems to have been formally discussed as early as 1950!), but since about 2002 it has come to be regarded as a serious problem, and steps are being taken to rectify it — although they do not seem to have progressed very far to date. The basic problem is that these are very large, heavy and expensive machines (hence, few spares are kept), they are relatively invulnerable to natural disasters (hence, there is little redundancy and few spares are kept), yet they can be destroyed surprisingly easily by deliberate attack. This is compounded by the fact that they are manufactured to order with an lead time of over a year. The National Academy of Science discussion can be found here:
http://www.nap.edu/books/0309084814/html/177.html