On the battlefield in Ukraine, fibre-optic-guided drones are now an everyday occurrence. Both Ukraine and Russia use them in large numbers for attacks, reconnaissance and disrupting logistics. Precisely because these drones are almost insensitive to classic electronic warfare, they have so far seemed nearly unstoppable. Against that background, the recent demonstration of the American Leonidas system from Epirus is striking: for the first time it has been shown that an electronic weapon can actually take out fibre-optic drones. See the video below.
Leonidas is not a jammer, nor a classic air defence system. The platform works with high-power microwaves that direct electromagnetic energy at a target. This does not disrupt the connection, but damages or destroys the drone’s electronics itself. That makes the system fundamentally different from existing countermeasures. Whether a drone is controlled by radio, fibre optics or autonomously is in principle irrelevant, as long as the electronics are vulnerable.
During a test at the end of 2025, Leonidas managed to take out a fibre-optic-guided FPV drone. That may seem like a small technical success, but operationally it is an important breakthrough. Fibre-optic drones are used precisely because they are immune to jamming and spoofing. That a non-kinetic system can still neutralise them breaks a tactical advantage that until now was seen as almost untouchable.
Why fibre-optic drones are so problematic
Fibre-optic drones owe their success to simplicity and effectiveness. A thin cable unrolls during flight and provides stable control and a live picture, without a radio signal that can be intercepted or jammed. In Ukraine they are used for one-way attacks, knocking out vehicles and observing movements behind the lines. Russian sources now speak of use at distances of up to fifty kilometres.
The problem lies not only in what these drones can do, but above all in their numbers. They are relatively cheap, quick to produce and are used en masse. Even if some are shot down, there are always enough left to cause damage. Kinetic means are expensive and inefficient, while electronic warfare has simply not worked against fibre-optic drones so far. The result: constant pressure on front lines and supply lines, without a reliable defence.
Leonidas tackles the problem at its core
Leonidas offers a fundamentally different approach. The system uses software-controlled phased-array antennas to emit microwave energy in a very targeted way. This allows a specific drone to be affected without much collateral damage. The effects are almost immediate: electronics fail and the aircraft becomes uncontrollable. Because it involves non-ionising radiation, the system is safe for personnel in the area when used correctly.
It is also important that Leonidas is scalable. In theory, one system can affect several drones in quick succession, or even simultaneously. That makes it relevant in scenarios where swarms or large numbers of drones are used — exactly the problem Ukraine and Russia face every day.
No miracle cure, but a crucial link
Leonidas will not eliminate the drone problem completely. Its range is limited, the system must be linked to sensors and it works best as part of a layered defence. But it fills a crucial gap: until now there was virtually no effective answer to fibre-optic drones other than shooting them down physically. Now, for the first time, there is a way to affect them on a larger scale. Especially around critical sites such as bases, logistics hubs and command posts, this can make the difference. Counter-drone drones, other systems such as the Mark 1 and, for longer range, NOMADS also remain part of the defensive shell. This creates a layered air defence.
War as an engine of innovation
The development of Leonidas fits a pattern that is becoming ever clearer: every new tactic provokes a counter-reaction. FPV drones led to jammers, jammers to fibre-optic drones, and fibre-optic drones now to microwave systems. War accelerates innovation, not in years, but in months.
The success of Leonidas shows that even trends that initially seem unstoppable – the massive use of fibre-optic drones – eventually get a counter-reaction. Not with one wonder weapon, but with new layers, concepts and ways of thinking. In a conflict where numbers are often more important than perfection, such a shift can make the difference.
