The Rise of Fiber Optics in Military UAVs

This proposal has sparked widespread disbelief online, with many questioning the feasibility of such a method. However, this guidance technique has a strong history of use.

When ZALA, a subsidiary of the Kalashnikov consortium, proudly announced that its new “Product 55” quadcopter drone was immune to any form of radio interference, it hinted at autonomy similar to that demonstrated in its previous developments.

However, a recently intercepted Russian FPV assault drone revealed a remarkably different and surprising technique for circumventing radio interference: instead of using radio signals, it maintains communication with its operator via a deployable fiber optic cable during flight.

On March 2, Ukrainian military blogger Serhii “Flash” shared details about an unusual type of Russian kamikaze FPV drone. This drone, in addition to its conventional explosive charge, carried a strange hollow plastic object containing an unidentified material. Flash asked his audience for ideas about the possible function of this object.

A few days later, he provided an update based on analysis by Ukrainian experts. After examining the drone, they determined that the enigmatic object was a spool of fiber optic cable linked to a Chinese-made high-speed optical transceiver. The label on the reel revealed that it contained 10,813 meters of cable.

Innovation in UAV communications: The fiber optic cable

“During a Ministry of Defense Hackathon, a participant suggested this same technology for UAVs,” he commented, “but I and other colleagues on the jury were skeptical about its feasibility. “A drone deploying 10 kilometers of fiber optics in the air without breaking the cable seemed implausible.”

This proposal has sparked widespread disbelief online, with many questioning the feasibility of such a method. However, this guidance technique has a strong history of use.

Evolution of cable orientation: From copper to fiber optic

The weapons provided by the United States to Ukraine include thousands of TOW-2 anti-tank missiles, a system with decades of service in the American arsenal, operational since 1970. TOW is the acronym for “Tube-launched, Optically tracked, Wire- guided,” highlighting its guidance method by a pair of copper cables that are deployed during the missile’s flight. The maximum impact distance is limited by the length of these cables (3.9 km).

This system was adopted in response to the vulnerability of earlier anti-tank missile radio links to electronic countermeasures.

The exclusive use of copper cables was to transmit control commands. However, with the advent of fiber optics, it was possible to devise an improved version capable of sending real-time video signals to the operator from the missile. This innovation was the basis of the US EFOG-M (Enhanced Fiber Optic Guided Missile) program in the 1980s, allowing operators to engage targets outside their direct line of sight.

Although competitors such as the infrared-guided Javelin missile and the laser-guided Hellfire limited its development, tests demonstrated the viability of the technology, although projects such as the long-range Polyphem missile were eventually discontinued.

Expanding the urban battlefield: Fiber-optic guided drones

Fiber optics have been viewed as a promising technology for unmanned aerial vehicles (UAVs). In the early 2000s, the United States Defense Advanced Research Projects Agency (DARPA) explored this possibility with the development of a kamikaze drone equipped with explosives within the Close Combat Lethal Recon program:

“… A portable, tube-launched, fiber-optic-guided explosive device designed for tracking operations, optimized for the pursuit of out-of-sight-range (NLOS) targets by individual combatants in urban environments… The guided munition shall be capable of attacking targets from widely extended approach routes, for example, flying over buildings or around corners, reaching distances of up to ten blocks, depending on the specific characteristics of the terrain and the urbanization.

This fiber optic guidance approach was eventually replaced by radio control systems, but many technological advances were incorporated into what would later become the SwitchBlade 300 loitering munition, produced by AeroVironment and currently in use in Ukraine.

Although fiber optic UAV control technology exists, its application remains a specialized niche without a broad commercial market. Oregon-based Timbercon specializes in fiber optic solutions with a range of products for drone control and video transmission, offering standard configurations and customizations for specific needs.

Innovation and adaptation: The new era of Russian drones

What stands out about the Russian drone design is not its origin in a traditional military complex but in one of the numerous Russian teams dedicated to UAV innovation with commercial components.

These projects range from drones with thermal imaging capabilities to systems that can remain in hibernation mode for weeks, waiting for activation, and even relay devices for long-range communications. Previously, state bureaucracy slowed down these developments, but the current situation allows for more agile progress.

The assembly composed of the cable coil and the optical transceiver significantly increases the weight of the drone, limiting the size of its payload. However, this system offers a crucial advantage: fiber optic communications are undetectable and immune to interference, an invaluable quality in scenarios where electronic countermeasures strategies determine the operational effectiveness of UAVs.

This development is not only relevant to the war context but also poses significant challenges for anti-drone defense systems in the Western world, which are primarily based on radio signal jamming or spoofing techniques. The possibility that any individual could build a fiber-optic guided drone in a home environment greatly complicates the security picture.

“I am already asking Ukrainian experts to evaluate this control technology to avoid being left at a disadvantage against the adversary,” says Flash, underlining the importance of quickly adapting to these technological innovations.