How To: Zap Bombs Before They Blow Up

By Noah Shachtman

A combination of technology and tactics has cut the number of improvised bomb attacks in Iraq by more than 50%. Some of the gear blocks triggering signals, before they can set an explosive off; some protects troops from blasts' impact; some looks for bombs' signature, in the trash and dirt that line Baghdad's roads. But perhaps the least-discussed gadgets are ones that blow up improvised explosive devices, or IEDs, before they're supposed to strike.

IEEE Spectrum, in an exhaustive feature on the tech of Iraq's IED war, looks at exactly this kind of gear:

A type of “predetonator” used in Iraq emits a strong electromagnetic pulse that wrecks the integrated circuits in the cellphone or other appliance that triggers an IED. The pulse comes from a very high voltage capacitor discharging very suddenly. When its ICs are zapped, the trigger might “fail open”—with no explosion—or it might “fail closed,” detonating the IED...

More sophisticated predetonators are said to mimic the signals of the IEDs’ triggering devices in order to set them off...

An article in the 25 March edition of The Scotsman newspaper... said that U.S. forces in Iraq and Afghanistan were using specially equipped Vietnam-era EA-6B Prowler aircraft to clear roads for convoys by transmitting appropriate signals to predetonate IEDs.

But how much impact has this or any equipment had on the bomb fight, really? At the Pentagon, much of the credit has been given to better training -- and better inflitration of the bomb-planting networks. And in Afghanistan (where, presumably, U.S. forces use the same tech), IEDs are way, way up.