IEEE Spectrum September, 2008 - 28

eutralizing an IED
means either disabling it or
destroying it. Both jobs are
performed by military specialists trained in the rapidly
expanding discipline known as explosive
ordnance disposal, or EOD.
U.S. EOD teams travel in 26-ton
technology-stuffed trucks called Joint
EOD Rapid Response Vehicles (JERRVs)
that cost more than $1.2 million fully
equipped (the JERRV was also a JIEDDO
project). The teams, usually made up of
two or three people, strive to disable and
recover unusual IEDs because of their
intelligence value. Those recovered IEDs,
as well as forensic evidence gathered at
places where IEDs have detonated, are
sent to a laboratory near Baghdad airport for analysis. IED specialists say that
years of work at that lab have enabled
them to know, in many cases, such details
as exactly who built an IED and possibly
where he built it.
If the IED isn't unusual, or if disabling
it doesn't seem straightforward, the EOD
technicians use special-purpose robots
to place plastic explosives on it and
blow it up. [In next month's issue, IEEE
Spectrum will publish a companion article to this one, on EOD in Iraq.]
There are other ways to neutralize an
IED. 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.
Inevitably, there has been a countermeasure, and a cheap one at that. "These
are billion-dollar solutions with ten-cent
countermeasures," says Daniel B. Widdis,
an instructor at the Naval Postgraduate
School, in Monterey, Calif., who did a tour
as an electronic countermeasures specialist in Iraq. [Editor's note: In response to
JIEDDO's request, IEEE Spectrum agreed
not to disclose the countermeasure.]
More sophisticated predetonators
are said to mimic the signals of the IEDs'
triggering devices in order to set them off.
In the typical case the triggering devices,
and therefore the specific codes that
will trigger them, are not known. In an
interview published in the 3 September
2007 issue of Aviation Week and Space
Technology, James M. Smith, the CEO of
EDO Corp., said that the predet systems
transmit sequences of codes very rapidly.
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NA * iEEE SpEctrum * SEptEmbEr 2008

When the right code comes up, the IED
detonates. The technique doesn't work,
however, if the code is long-say, 18 bits
or more. There are simply too many possible combinations, Smith said.
In February, JIEDDO announced that
it had canceled two big predetonator programs, code-named Alexis and Electra-C,
on the grounds that the signals from
those systems interfered with counterIED jammers such as Duke. A third program, called Blow Torch, is ongoing.
An article in the 25 March edition of
The Scotsman newspaper, which quoted
only anonymous sources, 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. (The article said
the sweeps are called courtesy burns.)
A former JIEDDO official points to
a tempting but difficult challenge for
future predetonators. "It would be a
breakthrough if we could find a safe and
effective way to predetonate blasting
caps," he says. "To underline the difficulty, remember that industrial and military caps are designed to not react to the
static electricity that creates lightning."

ow do you mitigate an
IED blast? Today, mostly
with armor. Over the past
year and a half, contractors
and soldiers have gone from
3-ton SUVs to 7.8-ton Revas, and from 5-ton
Humvees to 25-ton MRAPs and JERRVs.
Of course, there are disadvantages.
Tons of armor make vehicles too sluggish
to speed away from an ambush. And simple physics and economics confirm that
in an escalating contest between bombs
and armor, it's much cheaper and easier to make bigger bombs than to try to
shield against those bombs with more
and more armor.
But armor isn't the only factor in
the life-death equation. MRAPs and
JERRVs are much higher off the ground
than Humvees, and parts of their undercarriages are V-shaped. The V shape
deflects the force of a blast under the vehicle outward, away from the vehicle. The
increased height not only puts more distance between the passenger compartment and a bomb buried in the road, it
also makes it more difficult for insurgents
to target the passenger compartment with
an explosively formed penetrator.
The first MRAPs were delivered to
Iraq in January 2007; there are now more

than 3200 of them in combat roles. There
have been more than 150 IED attacks on
MRAPs, the U.S. Defense Department
says, which resulted in a total of eight
deaths. All the fatal attacks involved either
an EFP or a deep-buried IED. The Defense
Department plans to spend $5.4 billion
to buy 4000 more MRAPs, making this
acquisition program the Pentagon's third
largest (only missile defense and the Joint
Strike Fighter are bigger).
Future combat trucks will mitigate
blasts with more than simple armoring. Some of the competing designs
for the Joint Light Tactical Vehicle, the
MRAP's proposed more agile but no-lessblast-resistant successor, take inventive
approaches. For example, to reduce the
organ- and spine-crushing shock from a
blast that comes from below, some JLTV
designs suspend their seats from the ceiling, rather than bolting them to the floor.
"If I can vastly mitigate the effects of an
attack, I would argue that that is defeating the IED, too," says the Lexington
Institute's Gouré.

ver the past 5 years,
during which the U.S.
Department of Defense
spent more than $13 billion
on counter-IED efforts, the
IED did in fact become less effective. But
how much of that success is attributable
to technology? And was the money well
spent? The answers are elusive.
At the very outset of the IED problem
in Iraq, in mid- to late 2003, with soldiers
driving around in unarmored Humvees
and contractors in unaltered SUVs, almost
every IED attack caused a casualty. It now
takes roughly six IED attacks to cause one
coalition casualty, according to JIEDDO.
Slightly more than half of all IEDs
are found and cleared without detonating, JIEDDO says. Of those that do detonate, roughly 40 percent of them cause no
injuries. More heavily armored vehicles
are behind that statistic. And the more
technologically advanced JLTV promises
further improvements in survivability.
There are other indications of progress.
Insurgent groups typically pay people,
usually freelancers who are just in it for
the money, to emplace IEDs. Several years
ago, the going rate was about $50 per IED.
Today the rate is $200 outside Baghdad,
and $400 to $500 inside Baghdad, according to a counter-IED training official in
Iraq. The higher rates are believed to
reflect, among other things, the increased
risk and danger of the job.
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Table of Contents for the Digital Edition of IEEE Spectrum September, 2008