Gadget makes bombs, mines go off 'on average' 20m away
What's the value of σ here, exactly?
Colombian and Swiss boffins say they have developed a cunning electromagnetic device which can make landmines or terrorist bombs explode from a distance.
Félix Vega and Nicolas Mora, doctoral students at the école polytechnique fédérale de Lausanne (EPFL) in Switzerland, developed the bomb-triggering device as part of their doctoral theses. It works by using powerful radio waves to induce currents in the heating filaments within electrically-actuated detonators, so causing them to go off without benefit of any energy from the mine or device's firing system.
The radio waves are emitted in short, intense pulses, targeted at specific parts of the radio spectrum.
“We then realised that in spite of the wide diversity of these mines, they are however all in similar frequency ranges,” says Mora in an EPFL statement issued yesterday. “So we developed a system that concentrates on those, and thus loses less energy.”
According to the EPFL:
The EPFL Electromagnetic Compatibility Laboratory tested this system in Colombia last November, using actual improvised mines provided by a team of professional bomb disposal experts, which they were able to set off at an average distance of 20 meters.
That might do for clearing small landmines or bombs, but it would be dangerous for dealing with bigger devices – and large roadside or buried bombs intended to knock out armoured or protected vehicles are all too common these days. And "an average of 20m" means, of course, that
half some of the devices detonated closer than that.
In many cases, too, making a bomb go off just where the bomb-maker has placed it might be construed as helping him carry out his plan. The old bomb-disposal instructor's line "we have become the terrorist, haven't we" – often delivered sarcastically to trainee ordnance-disposal operators – might become relevant here.
But the two Colombian PhDs seem happy with their invention nonetheless.
“Now we have to develop a smaller prototype that is weather-resistant and especially easier to transport in the field,” says Vega. “In Colombia, we often have to travel on small country roads.”
Alternatively, one might try calling in some US "Prowler" electronic warfare aircraft, reportedly able to detonate roadside bombs from far above. Admittedly, the Prowlers may be/have been achieving a somewhat easier task – that of inducing firing currents in long command wires used to trigger bombs as US convoys pass them, rather than tiny filaments inside the detonators themselves (or wiring inside a compact device). A long receiving antenna makes transmitting significant amounts of energy easier – it seems that not everyone remembers to use twisted-pair firing wire.
Even if Vega and Mora could get their device up to the performance of US electronic-warfare planes, however, they would still be far from solving the problems of bombs and mines. It is a simple matter to build such things to function mechanically, without any electronics in them at all: no amount of cunning electromagnetic trickery will work against such a device. ®
Lewis Page is a former armed-forces explosive ordnance disposal (EOD, bomb disposal) operator.