The significant emphasis on security in the world’s airports and aircraft since 9/11 has led to greatly improved screening capabilities and new determination to prevent attacks of both the on-board and missile typse. However, on a recent flight I noticed that within a couple of hundred meters there were residential, pseudo residential or mixed residential / commercial areas, which brought to mind one of the classic attacks by the Provisional IRA – the mortaring of London’s Heathrow airport. It must be pointed out that there was considerable technical sophistication brought to bear, as the IRA had been improvising mortars for decades by that point. However, the details on building improvised mortars are not impossible to acquire – indeed, theoretically functioning military light and medium mortars (I’m thinking in the 81mm, ‘man-portable’ range) could be procured in South America and smuggled into the US.

The improvised version, often a rack of tubes with a timer concealed in a camper van or similar with a fabric roof painted and stretched to look like the real roof under casual inspection, is then parked within range of the airport, ideally at a place where the range has been calculated to spread the mortars around the areas of the taxiway where there are most likely to be hits on planes. It would be a lot more dangerous to man and control a real mortar, but completely feasible, particularly if one is not worried about being caught.

What are the implications? If there is a perceived threat of such an asymmetric attack, then every space where a vehicle can be parked within the range of an improvised system must be subject to some kind of monitoring; again, greatly increasing the burden on security systems and response. If there is the threat of the use of an attack using conventional mortars, then there should be significantly more intelligence warning (the training in the use of fire control as well as mortar systems), but the burden on finding the system, which is proportionately significantly busier given 3 mile-ish ranges, before an attack (after the attack starts it is simple to follow the noise – and flash if at at night), looking for what is relatively a very small target.

The real lessons? There are two. Asymmetric threats remain, and when dealing with an asymmetric threat both imagination as it relates to possible attack profiles, combined with contingency planning that deals with effects, not causes, is imperative.

Like the Twin Towers during 9/11, we cannot prepare for every possible contingency before they occur, but effective mitigation and emergency response plans – those that address the effects, whatever the causes – are essential.