Correction to This Article
Army Spec. Hugo Gonzalez was misidentified in two photo captions with the Oct. 1 installment of the Left of Boom series, and his rank was incorrect on Page One. Also, in some editions of the Oct. 2 installment of the series, the full name of an EFP, a type of weapon used by insurgents, was incorrectly given as "explosively formed perpetrator." It should have been "explosively formed penetrator."
PART 2 | SUMMER 2004 - SUMMER 2005

'There was a two-year learning curve . . . and a lot of people died in those two years'

By Rick Atkinson
Washington Post Staff Writer
Monday, October 1, 2007

As Gen. John P. Abizaid began his second year at U.S. Central Command in July 2004, the simple solutions he had hoped would defeat improvised explosive devices in Iraq seemed further away than ever. More than 100 American soldiers had been killed by bombs in the first half of the year, and IED attacks were spiraling toward an average of 15 per day.

Eager for creative ideas, Abizaid told Centcom subordinates in August that he would accept what became known as "the 51 percent solution": If a new counter-IED gadget or technique had a better than even chance of success, it would be welcome in the theater. "Listen, if you have something that's greater than 50 percent, then get it forward," he also told Brig. Gen. Joseph L. Votel, director of the Pentagon's Joint IED Task Force. "I've got the greatest testing ground in the world in Iraq."

That testing ground was soon put to use in IED Blitz, an elaborate experiment concocted in late summer by the Pentagon's joint staff.

Spotting bombs had proved fiendishly difficult. Some soldiers fastened rally lights on their Humvees for better visibility at dusk, or mounted leaf blowers on truck bumpers to clear the debris often used to camouflage IEDs. Aerostats -- small blimps with closed-circuit cameras tethered 300 to 1,000 feet up -- watched the landscape for insurgent activity. But soldiers staring at television monitors often found their concentration waning after just 30 minutes.

IED Blitz would focus as many forms of surveillance as possible in a "persistent stare" at a bomb-infested 20-kilometer stretch of Route Tampa, just south of Balad on the road to Baghdad. The blitz would enlist satellites, U-2 spy planes, 14 Mako unmanned aerial vehicles, a pair of larger I-Gnat drones, and the Horned Owl, a Beechcraft turboprop airplane equipped with ground-penetrating radar used to assess whether road shoulders had been disturbed by digging.

Attacks had grown increasingly extravagant, with "daisy-chained" munitions that included as many as 22 artillery shells wired together to explode simultaneously in a 300-yard "kill zone." Intelligence analysts assumed that such ambush sites took hours or even days to prepare. On the basis of past attack patterns, they predicted that 60 IEDs would be planted in 75 days on this short segment of Route Tampa.

Hundreds of thousands of photographs would be snapped as part of a technique called "coherent change detection." Two images of the same scene taken at different times would be compared, pixel by pixel, to spot changes in the landscape -- such as the anomalies caused by an insurgent planting a bomb. Ground convoys could be warned, and, if the reconnaissance was nimble, hunter-killer teams could flush emplacers or triggermen.

The operation, estimated to cost at least $3 million, would be directed from Defense Department offices leased in Fairfax County. "The only unacceptable outcome is to spend all this time and money and not have a definitive outcome because we didn't dedicate enough assets," a senior Pentagon official warned in one planning session. "Don't do it half-assed."

Blitz began on Tuesday, Aug. 24, 2004. So brilliant were the digital color images that analysts could read the brand names on plastic water bottles littering the roadside. They could distinguish an apple from a pomegranate at a fruit stand.

What they could not see was a bomb or a bomber. Technical problems soon emerged. A U-2 making two passes above the road seven hours apart had to fly routes within 5 degrees of each other for those pixels to align; the success rate was "way less than 30 percent," according to an Air Force officer. The I-Gnat routes needed to overlap within about 1 percent of each other, a comparably difficult task. Even blowing trash, a feature of every Iraqi landscape, sometimes made coherent change detection incoherent.

Sandstorms and high winds also plagued Blitz. Insurgents apparently monitored drone takeoffs from Balad airfield to calculate when they could safely move about; when two days of foul weather grounded the aircraft, six IED attacks occurred on Route Tampa. Numerous images showed Iraqis in pickup trucks staring into the sky and making obscene gestures at the drones, which were as noisy as lawn mowers.

When automated photo analysis did not work properly, analysts in Fairfax County were forced to manually review the pictures. "It was an eyeball event," the Air Force officer later recalled. "You have 5,000 images taken in the morning and 5,000 at night. The day shift would take 5,000, the night shift 5,000." The Blitz roadway was divided into five-kilometer segments with teams assigned to scrutinize each one. "If a paper cup was on that route and wasn't there yesterday," the officer added, "you knew it."

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