By Max Hunder
KYIV, July 10 (Reuters) - Russia has been using small drones flown via fibre-optic cables to bypass Ukrainian defences and damage high-voltage electricity substations in the frontline northern Ukrainian region of Sumy, open-source analysis shows.
Footage of the new spate of strikes, which has been posted on Russian social media channels, was verified by the Centre for Information Resilience, an open-source investigation group based in London, and confirmed by Reuters.
Russia has regularly
bombarded Ukrainian energy facilities, especially in frontline provinces, throughout the war. In response, Ukrainian authorities have covered high-voltage transformers with vast concrete sarcophagi and anti-drone nets.
Ukraine's frontline regions also teem with electronic warfare systems designed to disrupt the radio signals controlling the drones.
However, small, nimble First Person View (FPV) drones flown by fibre optic cable are immune to signal interference as long as their thin, translucent cable is not cut or snagged.
RUSSIA APPEARS TO WANT TO BLACK OUT UKRAINIAN REGIONS
Joshua Scriven, an investigator at CIR, said the Russians were creating holes in the protective netting by breaking it with a first drone before sending a second one through the gap.
Since May, Russia has been using these drones to navigate around the vast structures of the sarcophagus and find their way through ventilation holes to a central piece of equipment: the autotransformer.
Taking out the autotransformer, which in a 330-kilovolt substation is worth about $3.5 million, brings down the entire transformer unit, said Oleksandr Kharchenko, head of the Energy Research Centre in Kyiv.
CIR has verified four such strikes on large and seemingly well-defended 330 kV substations, and at least four more on smaller, less defended 110 kV substations.
The locations of the strikes on 330 kV substations range from 16 to 26 km (10-16 miles) from the frontline, according to Deepstate, independent producer of an online battlefield map, demonstrating the growing range of small fibre-optic drones.
"I think why they've started using them is because of these protective sarcophagi. They protect against missiles and Shaheds (heavy-duty drones),” Scriven said.
A fibre-optic FPV drone can cost as little as $2,000.
“The cost-benefit analysis there is staggering.”
Scriven said the strikes appeared to be part of an overall Russian strategy to isolate Ukrainian regions from the national grid and then black them out by attacking local power stations.
Sumy has suffered badly from Russian bombardment since summer 2024, when Ukraine launched an offensive into Russian territory from the province. It was pushed out last year, after which Russia launched its own attack into Sumy.
On Wednesday, Ukrainian Defence Minister Mykhailo Fedorov said the region's security situation had deteriorated in June.
“Russia's goal is to terrorise people and make life in the border regions unbearable,” he wrote.
The International Criminal Court has issued arrest warrants against senior Russian military commanders for strikes on Ukraine’s power grid between 2022 and 2023.
Russia denies targeting civilians and says all its strikes have a military purpose.
(Reporting by Max Hunder, additional reporting by Felix Hoske and Magdalini Gkogkou; Editing by Kevin Liffey)
