The first fiber optic drones have appeared in the Ukraine-Russia conflict. This innovative new UAV adaptation has already been prototyped by drone designers on both sides of the conflict and, with its unique resilience and stealth aspects, may soon become a force to be reckoned with.
What Happened?
On March 7th, 2024, Serhii Beskrestnov also known as Serhii Flash, a Ukrainian specialist on radio electronics and electronic warfare, shared pictures of a strange new Russian FPV kamikaze drone. Beskrestnov revealed that the drone operated, not off of radio broadcast signals like most drones, but through a thin 6.2-mile spool of fiber optic cable.
By March 18th, Dronaria, a Ukrainian drone development and production group, posted a view of their own fiber-optic drone prototype.
Why such a quick attempt by Ukraine to match Russia’s fiber optic drone technology? In this article, we’ll review what fiber optic cables are, the stealth and resilience advantages made possible by fiber optics for drones , the precedents for such technology, and the radar technology required to detect this new breed of military drone.
See Spotter Global's solution for "dark drone" detection here.
What are Fiber Optics?
Fiber optics are some of the world’s most highly efficient information-carrying cables. The secret to their efficiency is the speed of light.
The idea of sending information through light signals is centuries old. However, after years of scientific research into the properties of both light and light-refracting materials, engineers learned how to send data, encoded into light signals, through a core of optical fibers. Once in use, optical fibers were soon revealed to have many advantages over copper wires and fiber optic cabling has steadily grown in use since the 1980s.
Made of very pure, very thin, flexible glass at their core, fiber optic cables can be incredibly strong, thin, and lightweight. Standard optical fibers are often tested at tensile strengths of 100,000lb/in2 or more (so it takes a surprising amount of pressure to snap them). A single-mode fiber optic cable can be about as thin as a human hair and still deliver about 32 terabytes of data per second. Even with the plastic cladding wraps around the glass core of most fiber optic cables, fiber optic cables can be impressively lightweight and can be manufactured in great lengths. For example, there’s an incredibly long coil of fiber optic cable under the Atlantic Ocean that carries telephone signals from the eastern United States to western Europe.
So—what can a spool of fiber optic cable do for a drone?
How Can Fiber Optic Spools Change Drone Warfare?
Drones That Need Radio Can be Caught by Radio Jammers
Most drones receive their flight instructions via radio signals sent from their pilot. While fast and reliable, these radio signals make drones vulnerable to detection by RDF (radio directional finding)/RF (radio frequency) “sniffers” and susceptible to interference via radio jamming.
This reliance on radio signals and susceptibility to radio interference has shaped much of the back-and-forth drone activity on the Ukraine-Russia front line. Many drone missions, from either side, have failed due to radio jamming.
Some drone missions can be completed with preset flight paths that require no radio signal, but military drones responding to fast-changing battlefield dynamics often do not have that luxury. FPV drones in the Ukraine-Russia conflict are often sent out on surveillance or attack missions looking for targets of opportunity, which requires a strong, constant live connection between drone and drone pilot
Radio Jammers Can’t Stop Fiber Optic Drones
Having a drone “on a tether” may seem impractical at first. The tether might get tangled or otherwise create drag. But fiber optic drones bring certain advantages. With an ultra-light spool of fiber optic cable attached to a drone, it can fly well, avoid detection, and crucially, avoid radio jamming.
With all the pilot-to-drone communication taken care of by the fiber optic cable, fiber optic drones give off no radio broadcast signal for RF sniffers to pick up. As a result, their communications can't be jammed by radio jammers. The only way to cut off communication would be to cut the cable.
In short, fiber optic drones are harder to detect and harder to mitigate: a deadly combination for both surveillance drone operations and the kamikaze missions of drones carrying explosives.
Disadvantages of Fiber Optic Drones
Secure, undetectable fiber optic drone capabilities come with a price. Fiber optic drones fly more stealthily but might not be able to fly as far or deliver as much of a payload as normal, radio-signal based drones.
Fiber optic drones will be limited by the length of their spools. Even assuming the fiber optic lines won’t get tangled up in anything, missions will have to be completed within a certain radius.
As for payload capacity, fiber optic drones will have to carry the extra weight of a fiber optic spool containing many miles’ worth of cable as well as an optical transceiver for reading the fiber optic data. More weight from fiber optic-related equipment means less carrying capacity, smaller warheads, and less destructive capacity.
Thirdly, kamikaze drones often increase their effectiveness by flying in swarms. Coming in swarms makes it harder for defenders, including defenders of critical infrastructure, to down all the drones before at least some of them reach their intended target. Fiber optic drones could, theoretically, fly in swarms, but with multiple fiber optic drones flying in relatively close proximity, the risk of fiber optic tangling would be increased.
It remains to be seen how much either side will be willing to spend on fiber optic drones, especially as fiber optic cables can be expensive.
Precedents for Fiber Optic Drones
Though certainly coming as a surprise, the emergence of fiber optic drones isn’t completely without precedent.
There is a history of artillery missiles (which drones are being used to replace) including “tethered” models resistant to radio interference, such as the:
TOW-2 Anti-Tank Missile: Developed in 1970, these “Tube-launched, Optically tracked, Wired-guided” missiles used 2.4-mile dual lengths of copper wires to aid in navigation. This model has reportedly been present among the armaments given to Ukraine by the United States during the Ukraine-Russia conflict.
Spike LR2: These Israeli-made guided missiles use fiber optic spools of about 5.5 kilometers.
Also, the idea of fiber optic drones has been proposed to Ukrainian forces before. Serhii Beskrestnov, who has been an advocate of fiber optic drone innovations for some time, has stated that proposals were made for such technology during a previous Hackathon event organized by the Ministry of Defense of Ukraine. Such proposals were, on that occasion, rejected due to doubts about feasibility. But now the Russians are getting a start on fiber optic drones, and a prototype is already in Ukrainian possession, Ukrainian leadership may reevaluate their stance on this technology.
Questions About The Future of Fiber Optic Drones
Technical and logistical questions about fiber optic drones still remain.
How much fiber-optic range will fiber optic drones be given? Due to their smaller payload capacity, will fiber optic drones be used more for surveillance or kamikaze missions? Will fiber optic drones include a fail-safe to restore radio communication if the fiber optic wire snaps?
Have the Russians, as the first ones to develop this technology, already refined their design to their satisfaction? Will they soon commence mass or even limited production? How will Ukraine respond to this new threat and will they respond by producing fiber optic drones of their own?
It’s a stretch to imagine the no man’s land between Ukrainian and Russian forces densely littered and spiderwebbed with thin fiber optic cables—but it's not an impossibility.
What Would It Take to Detect and Mitigate a Fiber Optic Drone?
The steps are simple: detect and then mitigate.
Radio waves may still have a role to play in drone detection, but instead of picking up drone-broadcasted frequency communications, radio waves would have to be used to detect the radio-silent drone body/housing in the air. Fiber optic drones may be able to hide their communications but not their physical matter.
Compact surveillance radars (CRS) are the sensor of choice for “dark” drone threats. Able to detect airborne perimeter breaches through low-light, fog, smoke, and other low visibility conditions, compact surveillance radars use radio waves for object and motion detection. The radio waves emitted from the radar bounce off of anything present in the airspace and return to the radar setup, delivering information on the size, speed, and trajectory of the target.
When it comes to defense, especially around sensitive areas, perimeter threats need to be quickly detected and confirmed. Smart software built into CSR systems allows radar setups to immediately detect live drone threats and just as quickly distinguish drone targets from nuisance alarms such as birds flying by.
As pioneers in compact surveillance radar for military and domestic defense, Spotter Global has deployed more than 400 drone-detecting radars to protect military and critical infrastructure sites worldwide. For larger sites and locations dealing with high-altitude drone threats, we recommend our AX250 3D Dome model (seen below) designed to catch “dark” drones coming in from any angle, including the high-altitude diving maneuvers that fiber optic drones may favor.
As for mitigation, when radio jamming won’t work, more “hard kill” methods may be needed. Firearms, though not always successful, have been used to take out drones. The United States Navy has successfully tested a laser weapon system to shoot down drones. And in some cases, net guns, drone vs. drone combat, or even trained falcons have been used to mitigate active drone threats.
Staying Vigilant at Home
Threat developments in military zones around the world, all too often, eventually become threats on home soil.
In this age of abundant information, news of new military tactics and technologies spreads quickly. Those looking to do harm in the domestic arena are typically all too happy to adopt innovative ideas from zones of armed conflict. Many military-developed technologies eventually become commercialized and put into the hands of the public, where they can be adapted by nefarious parties to do all kinds of harm, but some determined parties will wait only for news of new methods before attempting to replicate them for their own ends.
Our aim is to stay ahead of the curb. If fiber optic drones are successful in the Ukraine-Russia conflict, they may soon become a weapon of choice for DVE (domestic violent extremists) intent on disrupting critical infrastructure. Security professionals tasked with defending critical infrastructure need to know what drones are capable of and be prepared for their use by DVEs.
Staying updated on drone developments through the Spotter blog. Also, for security professionals concerned about drone threats, live demos of Spotter Global radars, including the AX250, can be requested. Contact us to get a demonstration or a quote for a Spotter radar.
In the meantime, stay tuned for more information regarding fiber optic drones, other drone developments, and perimeter security news. And stay safe.