Army’s New Weapon: Laser-Guided Lightning

The US Army wants to add lighting bolts to its arsenal of weaponry.

Scientists and engineers at Picatinny are developing a device that will shoot lightning bolts down laser beams to destroy targets. The Laser-Induced Plasma Channel, or LIPC, is designed to seek out targets that conduct electricity better than the air or ground that surrounds them.

“We never got tired of the lightning bolts zapping our simulated (targets),” said George Fischer, lead scientist on the project.

The weapon idea imitates the way in which lighting leaps from thunderclouds to strike the ground — the electrical energy follows the path of least resistance, he said.

A guided lightning bolt travels horizontally, then hits a car when it finds the lower-resistance path to the ground. The lightning is guided in a laser-induced plasma channel, then deviates from the channel when it gets close to the target and has a lower-resistance path to the ground. Although more work needs to be done, Picatinny Arsenal engineers believe the technology holds great promise. (Image: US Army)

The team used an ultrashort-pulse laser of modest energy to make the laser beam intense enough that it could focus on itself in air and stay focused in a filament, he said.

“If a laser beam is intense enough, its electromagnetic field is strong enough to rip electrons off of air molecules, creating plasma,” Fischer said. “This plasma is located along the path of the laser beam, so we can direct it wherever we want by moving a mirror.”

Although the engineers working on the weapon’s development expressed confidence in the physics behind their work, Fischer cautioned about the technical challenges still ahead.

“If the light focuses in air, there is certainly the danger that it will focus in a glass lens, or in other parts of the laser amplifier system, destroying it,” Fischer said. “We needed to lower the intensity in the optical amplifier and keep it low until we wanted the light to self-focus in air.”

Other challenges include synchronizing the laser with the high voltage, ruggedizing the device to survive under the extreme environmental conditions of an operational environment, and powering the system for extended periods of time.

Despite the challenges, Fischer said the project has made significant progress in recent months.

For more information, visit: www.army.mil