WASHINGTON — At the vast, windswept White Sands Missile Range in New Mexico earlier this year, nearly a dozen military contractors armed with laser guns, high-tech nets, and other experimental systems met to tackle one of the Pentagon’s most vexing counterterrorism conundrums.
The goal is to destroy the Islamic State’s increasingly lethal fleet of drones.
The militant group has used surveillance drones on the battlefield for more than two years. But an increase in deadly attacks since last fall has highlighted the terrorists’ success in adapting off-the-shelf, low-cost technology into an effective new weapon.
The drones have mostly been used to target Iraqi troops and Syrian militia members with small bombs or grenades, but they also pose a threat to US advisers.
The Pentagon is so alarmed by this growing threat — even as it routs the Islamic State from its strongholds in Mosul, Iraq, and Raqqa, Syria, — that it has launched a $700 million crash program overseen by two senior Army generals to address it.
The program is drawing on the collective know-how and resources of all branches of the armed services, Silicon Valley, and defense companies like Boeing and Raytheon to devise tactics and technology to thwart the menace.
One important piece of that effort was the contest in New Mexico. It amounted to a Pentagon counter-drone bake-off, called the Hard Kill Challenge, to see which new classified technologies and tactics proved most promising.
The results were decidedly mixed, and underscore the long-term problem confronting the Pentagon and its allies as it combats the Islamic State and Al Qaeda in a growing number of hot spots around the world beyond Iraq and Syria, including Yemen and Libya.
“Threat targets were very resilient against damage,” the Pentagon agency assigned to help crack the problem, the Joint Improvised-Threat Defeat Organization, said in response to questions from The New York Times about how the contractors fared against mock enemy drones. “Bottom line: Most technologies still immature.”
The agency said some of the technology might work well with “adjustments and further development.”
In the meantime, the Pentagon has rushed dozens of technical specialists to Iraq, Syria, and Afghanistan to help protect US troops and to train and, in some cases, equip local allies against the drone threat, which has killed more than a dozen Iraqi soldiers and wounded more than 50.
The aircraft, some as small as model airplanes, conduct reconnaissance missions to help Islamic State fighters attack US-backed ground forces. Other drones drop bombs or are rigged with explosives to detonate on the ground.
“These things are really small and hard to detect, and if they swarm in groups, they can overload our ability to knock them all down,” said J.D. Johnson,
US troops are using an array of jammers, cannons, and other devices to disrupt, disable, or destroy the enemy drones, often quadcopters rigged with explosives. And the military has increased airstrikes against Islamic State drones on the ground, their launch sites and their operators.
“This isn’t just an Iraq and Syria problem; it’s a regional and global problem,” Lieutenant General Michael Shields, director of the threat-defeat organization and one of the two generals overseeing the effort, said in a telephone interview. “These are airborne IEDs,” meaning improvised explosive devices.
The peak of the threat came this spring during the fight to wrest Mosul from Islamic State control in northern Iraq, military officials said. Since then, the military has repeatedly attacked Islamic State drones in the air and on the ground.
Earlier this month, the Pentagon said it had killed Junaid ur Rehman, a senior Islamic State drone pilot trainer and engineer, in an airstrike near Mayadin, Syria, south of Raqqa.
“We are destroying their launch points, we’re killing their engineers, we’re dismantling their manufacturing facilities and their users,” said Colonel Ryan Dillon, a spokesman for the US military in Iraq.
In Washington, however, Pentagon officials worry about the rapid spread of armed drones to other conflict zones, where the United States and its local partners may be less prepared to confront the threat.
In February, the Defense Department created a special task force headed by Lieutenant General Anthony R. Ierardi, a top officer on the military’s Joint Staff, to coordinate a Pentagon-wide counter-drone campaign along with Shields.
“These are learning experiences, and the adversary will adapt,” said Ierardi, who added that the Pentagon’s $700 million effort was likely to grow in the next few years.
Some of that money will go to help organize events like the Hard Kill Challenge in New Mexico, where major defense contractors including Boeing and BAE Systems, as well as much smaller specialty technology companies, participated in a five-day competition that extended longer for some firms.