Fans of Back to the Future will remember Doc Brown's belief that 1.21 gigawatts of electricity could power a time machine. Real lightning delivers far more in a sudden burst, but for now, that energy remains impossible to store.

What it can do, though, is cause immense disruption, damaging buildings, knocking out power lines, and threatening human life. In Japan alone, the economic impact is estimated at up to 200 billion yen (around US$1.3 billion) annually.

While traditional lightning rods offer some protection, their range is limited and they can't always be installed in vulnerable places such as wind turbines, construction sites, or large outdoor gatherings. Society has largely accepted lightning as unpredictable and uncontrollable.

Triggering Lightning

A recent experiment by the NTT Information Network Laboratory Group suggests that might be about to change. Over the course of two months from December last year, the company successfully triggered and guided a lightning strike using a drone, the first time this has ever been done under natural storm conditions.

The setup involved a commercially available drone fitted with a custom-designed protective cage made of conductive metal. During a lightning-prone moment in Shimane Prefecture, in western Japan, ground-based sensors detected a sharp rise in the electric field beneath a thundercloud. At the right moment, the drone was flown to 300 meters and electrically connected to the ground via a conductive wire. When a switch on the ground was activated, the local electric field changed abruptly, creating ideal conditions for lightning to discharge. A high-voltage current then surged through the wire, striking the drone with a visible flash and a loud bang.

And the result? The drone survived the strike. Its cage design redirected the current away from internal components and distributed it outward in all directions from the strike point, helping to cancel the magnetic fields that might otherwise have interfered with flight control. Although part of the cage melted slightly, the drone was able to continue flying.

Working in Theory, Working in Practice

Information Network Laboratory Group researchers were confident their design would work, because they had already tested it with artificial lightning of up to 150 kA, or 150,000 amperes, far stronger than typical natural strikes. To give an idea of perspective, a typical household circuit carries just 10–30 amperes. Although confident of getting a good result, this real-world success confirmed to researchers that the concept would work not just in theory, but in practice.

Small, Inexpensive and Flexible Drones

NTT's system is quite different from earlier methods, such as rocket-induced or laser-triggered lightning. Rockets require heavy infrastructure and involve regulated explosives, while laser systems demand huge amounts of power and are fixed in place. Drone-induced lightning, however, uses small, portable equipment and a simple ground-operated switch. It can be deployed quickly and moved to match storm locations.

What's the Worst That Could Happen?

If a strike fails to occur, the only cost is a drone and some cable, not a rocket or a high-energy laser array. It's an inexpensive, flexible solution that could prevent damage to infrastructure and danger to living beings.

Future Uses

Beyond proof of concept, there are already several directions this technology could take. In cities, drones could be dispatched ahead of storms to patrol sensitive infrastructure, drawing lightning away from hospitals, airports, or power grids. For temporary outdoor venues, a fleet of drones might offer more flexible protection than static rods. In the research world, having a reliable way to trigger lightning could lead to deeper insights into atmospheric electricity and storm behavior, which still contain many unknowns. There's also potential in equipment testing, simulating real lightning strikes in situ for wind turbines or remote towers.

Great Scott!

And who knows? Perhaps one day we might be able to capture the enormous energy of a strike. Lightning delivers a sudden burst of electricity, millions of volts in a fraction of a second. Storing that energy is a difficult problem, but if it can be done, drones could become tools for harvesting rather than just diverting lightning.

For now, NTT plans to refine its technology by improving the accuracy of lightning prediction and continuing to study how lightning forms. It's still early days, and we won't see drones replacing every lightning rod immediately. But the concept of flying machines that can attract lightning, survive the strike, then steer it safely to ground is something new.

Innovating a Sustainable Future for People and Planet

For further information, please see this link:
https://group.ntt/en/newsrelease/2025/04/18/250418a.html

If you have any questions on the content of this article, please contact:
Public Relations
NTT Information Network Laboratory Group
https://tools.group.ntt/en/rd/contact/index.php

Daniel O'Connor

Daniel O'Connor joined the NTT Group in 1999 when he began work as the Public Relations Manager of NTT Europe. While in London, he liaised with the local press, created the company's intranet site, wrote technical copy for industry magazines and managed exhibition stands from initial design to finished displays.

Later seconded to the headquarters of NTT Communications in Tokyo, he contributed to the company's first-ever winning of global telecoms awards and the digitalisation of internal company information exchange.

Since 2015 Daniel has created content for the Group's Global Leadership Institute, the One NTT Network and is currently working with NTT R&D teams to grow public understanding of the cutting-edge research undertaken by the NTT Group.