This article originally appeared in Popular Science.
Before I could lock the laser weapon’s crosshairs on the DJI Phantom drone, I had to make sure it was in the right position. With the drone against a cloudless blue sky, the weapon’s sensors could clearly see and track it, but hard-coded rules of engagement prevented the weapon from firing until the target had an earthen backdrop. Light travels far, and we don’t want to accidentally zap the wrong thing that’s far away.
The target drone’s pilot directed the Phantom below the horizon line, with some landmass behind it. On the laptop in front of me, I placed a tracker marker just to the side of the drone, a push of the left joystick of an Xbox controller fixing the tracker to the target. With a slight nudge of the right joystick, I moved my crosshairs onto one of the quadcopter’s rotors, and then held the trigger. The Phantom lit up on the infrared view, and 15 seconds later it crashed down, the molten plastic of the rotor arm bending on impact.
I set the controller down and an engineer flicked the “armed” switch to the off position. It was my first time firing a laser weapon.
The 10-kilowatt laser in question was a High-Energy Laser Weapon System built by Raytheon, and I was invited by the company to observe it in operation at the Energetic Materials Research and Testing Center, part of New Mexico Tech, in Socorro, New Mexico.
To get to the range, we had to take a four-wheel drive vehicle onto the dirt roads, about six miles behind Socorro Peak. While New Mexico Tech has its origin in mining, its proximity to White Sands Missile Range (and the availability of EMRTC itself) have kept other defense contractors, like Northrop Grumman and Aerojet Rocketdyne, as range tenants.
Some of what is tested at the range is explosives. The shape, composition, and aerodynamics of artillery can all be studied through live fire. On the other side of the ridge from where Raytheon has set up its work station came the unmistakable thunder of artillery. Around the testing area were several M110 Howitzers, artillery pieces on treads that the US retired in 1994.
This old artillery, juxtaposed against a field demonstration of lasers disabling drones, illustrated one of the realities of modern warfare. Artillery can remain effective for decades after it enters service, but drone scouts are changing how armies move and fight, and how armies direct artillery fire, too. The lasers are a reaction to those drones, and an attempt to make drone destruction simple, effective, and in the long run, affordable.
As we arrived on site, past the weathered cannons, I disembarked from the SUV and saw a launch zone of roughly ten or so DJI Phantom 4s. Depending on the model, these drones can cost up to $3,500 each. That’s on the higher end of DJI’s commercial offerings, but an order of magnitude cheaper than the most bare-bones drones designed for military use. At the range, these Phantoms were lined up like clay pigeons, waiting their turn in the sky before being shot down.
Frying these drones would be a pair of High Energy Laser Weapon Systems (HELWS), made by Raytheon. One was mounted on the back of a Polaris MRZR, a military grade dune buggy. The MRZR still had the two front seats, and in the back sat the power supply and targeting system for the HELWS. Next to the buggy-mounted laser weapon was an identical system, only this one was on the bed of a large truck. In the field, HELWS is designed to be battery powered, but for today each was running off a portable generator, burning gasoline.
A relatively small amount of fuel would power the two lasers in use that day for the whole of their operations. By the end of the day, 10 DJI Phantom 4s would lie, collected, in various states of destruction. At roughly $3,000 apiece, depending on the model, that’s $30,000 in drones destroyed for roughly what it takes to fill up a small car.
This cost disparity, between cheap drones and even cheaper laser takedowns, is an explicit reason for developing laser weapons. Current means of destroying drones in the field can risk overkill, and come with various drawbacks.
“It has to be a cost-effective solution for soldiers to be able to use it,” said Annabel Flores, chief operating officer of Global Spectrum Dominance at Raytheon Intelligence and Space. “It makes no sense to shoot something that’s hundreds of thousands of dollars or a million-dollar missile into something that’s a thousand dollars.”
In 2017, a US ally reportedly fired a Patriot anti-air missile at a hobbyist quadcopter. Patriot missiles are designed to intercept cruise missiles and airplanes, and they cost about $3 million apiece. Patriots are also made by Lockheed Martin and Raytheon, and while the missile was effective against the drone, the cost difference is so great it was at best a Pyrrhic victory. It’s like killing a mosquito using a grenade.
“That’s just the wrong side of the cost equation that you wanna be on,” said Flores. “What fundamentally drove us down this path is that this is a real need and a real solution.”
The cost of each laser activation is only part of the equation. Raytheon has been awarded at least $52.4 million to develop and deliver HELWS systems to the Department of Defense. Those prototypes and models have been put through the paces, with deployments outside the United States and 25,000 hours operational hours.
“The next step for us is really being prepared so that it’s not just a cool demonstrator, a cool prototype, but these are producible systems that assembly technicians are putting together today,” said Flores. “Originally physicists were the ones that were working with lasers, then it became engineers while we were doing these proofs. Now it’s assembly technicians that are pulling these systems together.”
What I saw on the monitor in front of me
On the drive to the range, my hosts asked if I play video games. It’s been a decade since I really spent time on a first-person shooter, but there’s a muscle memory to video game controllers that persists. The controls for the laser were set up inside a nearby trailer with plywood walls, but they could fit into a backpack easily. Firing the HELWS laser is done through a program running on a laptop, which is fed information by ethernet or fiber-optic cord. In my hand, controlling the turret and the laser, was the plug-in Xbox controller.
The laptop’s screen was divided into quadrants of different sizes. In the upper-left, there’s a wide view from the electro-optical camera, showing a slice of surrounding terrain. In a smaller window on the upper right is a narrower view, looking down the “sight line” of the laser. (More on that in a moment.) Below the narrow view is a compass on a map, showing the direction the vehicle is facing, the orientation of the laser, and when designated, any targets in view. That quadrant also has columns for “cues” that the camera can quickly pivot to, which could be predetermined points to focus on or could be new drones added to the system by sensors.
In the bottom-left of the screen was a landscape-oriented photographic panorama of the area surrounding the laser. This image was captured by the camera pod, and it has layered data on top. A bright red line traces the horizon, hard-coding a boundary that, for this range on this shoot, the laser is not permitted to fire above. In a cluster, beneath a high slope, sit several green rectangles, marking fields of vision and fire zones. Within those settings, the laser turrets can track and then fire and melt drones, but above the horizon line or outside the box, the trigger pull on the laser won’t work.
This capability, which was set by other menus, is useful on the training range, and has applications in the field. A laser deployed to protect a power plant, say, may want to be hard-coded with certain areas as off-limits, to be absolutely sure the laser doesn’t hit infrastructure by accident.
Arming the laser
Before firing the laser, it needs to be armed. A safety interlock box with two toggles lets users turn on the laser weapon, and turn on a laser illuminator, which is distinct from the laser weapon. The illuminator is used for targeting, but can also cause harm and disorientation if pointed in a person’s eyes. To ensure that the laser cannot be set up without command authorization, the toggles can be locked off by a key, carried by a commander.
With the controller in hand, targeting the laser is something like playing a video game, though one where the difficulty of aiming in infrared is hard to ignore, rather than eased for sake of playability. Once an object is designated as a target, the turret can follow it well, but zooming around to find the object can be tricky, especially against the juniper-speckled hills of the high desert.
In the field and at other ranges, optical identification can be aided by radar data, which can ping and track new drones arriving within range. With this, a laser gunner can “Slew to Cue,” or toggle between tracked objects the way a remote flicks between favorite channels.
Firing the laser
The laser of the HELWS is housed in the body beneath the turret, and it points upwards at a lens that focuses it. This orientation also lets a camera point in the same direction, giving the video feed a perspective that’s equivalent to looking down the barrel of a gun, though the laser has no barrel and is not a gun.
The HELWS laser is built into an existing Raytheon camera and laser designator pod. Remove the laser weapon, and the pod’s infrared and electro-optical cameras, as well as the laser illuminator, can be found on vehicles like Predator drones and C-130 planes. The illuminator can seem redundant, but in action it can even out the image on the camera while the laser weapon itself is powered on. In the infrared view, the heat of the laser distorts the target, a bright glowing spot over what was once clearly drone features. With the illuminator, the heat appears washed out, and the laser on the target can clearly be seen.
The laser has an effective range of 3 kilometers, or just over 1.8 miles. The speed at which the laser can burn through a target depends on a host of factors, not least of which is the air itself. Had the day been rainy, or windy and dusty, the visit would have been rescheduled, as the particles in the air can hinder its function. The laser’s time to destroy a target is also determined by the steadiness of its focus, the wattage of the weapon, and the material of what it was firing against.
To get a feel for the laser before firing it at drones, some targets were set on a board, with another board on a stand behind it. These included inert 20mm rounds with rubber tips, mock grenades, cans of energy drinks and soda and, later, an ammunition box. One of the 20mm rounds lit like a candle under the laser fire, as the heat from the metal moved upward to burn off part of the rubber tip. The soda cans popped and drained, thin metal heating quickly and bursting outwards. The empty ammo box burned open in seconds. The grenades were uneventful. The cement backing of the board behind the objects melted, cement and fiber looking glassy, crystalline upon examination afterwards.
Against drones, the key factor for how long a takedown took was what part of the drone was hit. Battery casings took the longest. A clean shot into the hull and electronics could down a drone in 8-10 seconds. My long shot on the rotor, which melted part of one arm, was the slowest of the day, at 15 seconds.
Modern weapons for modern battlefields
Ultimately, it’s hobbyist drones used as cameras that have sustained the Pentagon’s interest in the HELWS and weapons like it. Prior to drones, aerial surveillance was expensive, requiring planes or helicopters, and could be neutralized with expensive weapons. Now camera drones, even ones cheap enough to buy at a store, are useful enough that forces fighting on both sides in Ukraine see them as essential. The drones can scout, sometimes even attack, and guide artillery fire. In real time, soldiers operating long-range weapons can see not just where to shoot, but the impact of a shot after the dust settles. The lasers, mounted on trucks and buggies, are a way to prevent that, to incapacitate drones and leave foes without that information in the field.
Throughout the day, the boom of artillery would occasionally interrupt conversation, adding extra ambiance. The laser testing facility was, ultimately, a trailer and a few four-wheel drive vehicles, parked on a hill with some porta-potties and sparse bunkers. The landscape was beautiful, especially at a distance. Worn and rusted metal collected in certain spots, and hardy plants with sticky seeds dug into everything.