NTT says it has triggered lightning with a drone for the first time
NTT said it has successfully induced and guided lightning with a drone in a real thunderstorm, a first the company says could open a new path to protecting critical infrastructure.
The demonstration targets a costly problem that conventional lightning protection has not eliminated. Lightning still causes an estimated 100 billion to 200 billion yen in damage each year in Japan alone, even as utilities and telecom operators deploy lightning rods and other defenses across critical networks. Those systems work best where fixed protection can be installed and where the strike zone is predictable. They are less effective for large open areas or structures such as wind turbines and outdoor venues, where coverage is limited or installation is difficult. NTT has been developing an alternative approach that uses a drone to move under a thundercloud, trigger a strike on demand and then steer the discharge away from assets and people.
The field test was carried out in a mountainous area near Hamada City in Shimane Prefecture at an altitude of about 900 meters between December 2024 and January 2025. Researchers monitored atmospheric electric fields on the ground with a field mill as storm clouds approached. When the electric field intensified on Dec. 13, 2024, the team flew a drone carrying a conductive wire to an altitude of 300 meters and connected the aircraft to the ground through a switch installed below. NTT said a large current then flowed through the wire while the surrounding electric field changed sharply. Just before the strike was induced, voltage between the wire and the ground exceeded 2,000 volts. The company said the abrupt shift in the electric field around the aircraft triggered lightning to the drone. It described the result as the world’s first successful lightning induction using a drone.
The experiment tested two core technologies. The first is a lightning-resistant cage mounted around the drone. The metal shield is designed to divert lightning current around the aircraft instead of through its body. It also spreads that current radially to reduce the magnetic-field effects that can damage onboard systems. NTT said artificial lightning tests showed the cage could cover more than 98% of natural lightning strike conditions and protect the aircraft from malfunction even under a 150-kiloampere discharge, about five times the average natural strike. In the real-world test, the induced strike produced a popping sound, caused the winch to glow and melted part of the protective cage. The drone, however, continued flying stably after the hit. The second technology is an electric-field control method designed to actively trigger lightning rather than wait for a random strike. By linking the airborne drone to the ground with a conductive wire and closing a high-voltage switch at the right moment, the system sharply increases the electric field around the aircraft and makes a strike more likely.
The broader goal is to create a mobile lightning protection system for places where fixed lightning rods cannot do the job alone. If paired with high-accuracy strike forecasting, hardened drones could be dispatched to predicted lightning locations, trigger the discharge and guide it to a safe area before it hits a building, grid asset or crowd. NTT said the next steps are to improve lightning location prediction, deepen research into how lightning forms and explore whether induced strikes could be stored and used as energy. If those efforts succeed, the technology could shift lightning protection from passive defense to active control, with implications for telecom networks, renewable energy sites, public venues and urban safety.