SAN ANTONIO — As Islamic State-piloted commercial drones complicate the offensive in Mosul, sending Iraqi troops scattering as grenades and bomblets rain down, the Army has field tested vehicle-based lasers to combat the growing threat of enemy eyes in the sky.

Infantry-carrying Stryker vehicles mounted with the Mobile High Energy Laser, a 5-kilowatt beam that scrambles the circuits of drones, took part in demonstrations at the Maneuver Fires Integration Experiment at Fort Sill in Oklahoma, a 10-day exercise that ended last week.

The system includes radar detection and a camera to visually track aircraft on a screen, where an operator targets the drone with the laser. A "hard kill" will disable the drone mid-flight and send it crashing to the ground, the Army said. A "soft kill" occurs when the laser severs the communications link between the drone and its ground control station.

"[Then] we can send artillery after the ground control station," Lt. Col. Jeff Erts of the Fires Battle Lab at the Fires Center of Excellence at Fort Sill said in an Army story about the exercise.

In all, 50 drones were brought down during the exercise, the story stated.

The laser, which does not emit a sound when it pulsates, is the centerpiece of an experimental Stryker variant used during the field exercises.

It is mounted atop the 16.5-ton infantry vehicle where a .50 caliber machine gun or Mk 19 automatic grenade launcher would be, outside the vehicle commander's hatch. An M240B machine gun replaces that weapon, according to an Army video demonstrating the vehicle.

The counter-drone mission has been given to reconnaissance units, a soldier in the video said.

Future use

It remains unclear how effective the weapon could be in operations against larger, more sophisticated unmanned aircraft used by conventional militaries, whose signals could be better protected as the aircraft fly much higher than commercial drones.