23-05-2025
NTT develops world's first 'flying lightning rod' using drones
Telecom giant NTT has developed what it describes as the world's first 'flying lightning rod,' or drones that will trigger lightning and redirect it safely to the ground to prevent it from striking people or vital infrastructure.
In multiple field tests in the mountainous areas of Hamada, Shimane Prefecture, between December and January, the company flew a drone equipped with a proprietary lightning-resistant cage to an approaching thundercloud when it noted the electric field intensity at ground level had increased, signaling an impending lightning strike.
The drone, which was connected to the ground with a wire, triggered a lightning strike — marking the first time such a feat has been achieved globally, according to NTT — with the 2,000 volts of electric current flowing through the wire.
The drone's protection cage was partially damaged, but the drone was able to continue flying, the company said.
NTT has been developing measures to avoid lightning strikes on its communications infrastructure. According to the Institute of Electrical Engineers of Japan, lightning-related damages are estimated at ¥100 billion ($700 million) to ¥200 billion annually.
In April, six students were hospitalized after they were struck by lightning at a junior high school playground in Nara Prefecture. Such incidents underscore the limits of lightning rods, which offer only localized protection and cannot be installed in many environments like wind farms or open-air venues.
NTT's technology offers a new approach to prevent lightning strikes — flying the drone into the thundercloud and triggering lightning, then redirecting it. Its drone employs two key technologies: a metal shielding cage that can withstand lightning and an electric field manipulation technique that boosts the likelihood of attracting a strike.
The drone was stress-tested against artificial lightning up to 150 kiloamperes, five times stronger than typical strikes, with no malfunction — effectively protecting against over 98% of real lightning scenarios.
NTT plans to refine its technology to improve the accuracy of lightning prediction and develop methods for capturing and storing lightning energy.
With the technology, NTT said it hopes its flying lightning rods will one day shield cities and digital infrastructure from strikes, with hopes of building a 'lightning-free society.'
