Seeing Ukraine’s success, other countries are following suit, including the UK. In May, the government announced £10m of support for Project NYX, an Army demonstrator programme intended to develop uncrewed air systems that can act as “loyal wingmen” for Apache crews. Four industry partners – Anduril, BAE Systems, Tekever and Thales UK – have been selected to develop designs, with the strongest expected to move towards prototype development later this year.
The goal is to reduce the risk of flying sorties in challenging conflict environments. Rather than Apache pilots having to fly into danger alone, autonomous drones could scout ahead, identify targets, conduct reconnaissance, support electronic warfare or even conduct precision strikes. The Ministry of Defence (MoD) says the drones will give Apache pilots information without requiring them to control the aircraft directly, while any decision involving the use of weapons would remain with a human.
But it all requires solving a tricky engineering challenge – how do you keep drones airborne if an adversary manages to lock on to them?
“There are essentially two ways to bring down a drone,” says Arthur Holland Michel, a journalist and researcher specialising in drones. “One is via electronic means, which means either jamming it or hacking it, and the other is via kinetic means, which means either shooting it down or trapping it.”
Each of those two threats requires a different type of approach to defence. Electronic warfare is about attacking the invisible systems that tell a drone where it is and what it needs to do. Kinetic defence is, in theory, more straightforward: either hit the drone, intercept it or trap it to stop it reaching its target.
To ward off the electronic threat, maintaining the link between the drone and its operator is vital. If that electronic link is jammed, the drone can lose its command signal, video feed or navigation. Disruption does not necessarily mean completely destroying that link, either – spoofing it can allow opponents to take control of a device and render it useless.
One way to avoid that is to shift the radio frequencies used. “You can hop frequencies, so that whichever frequencies your adversary is trying to jam, you can evade that jamming,” Michel says.
“You can also rely more on autonomy, meaning that you sever the radio connection between the human operator and the drone for as much of the operation as possible.”
But the more you do that, the less control you have over a drone’s flight. The MoD’s Project NYX announcement explicitly stated that humans will continue to make weapons decisions. It seems likely that more of the flight and coordination work will be pushed onboard, however.
In Ukraine and the Middle East, fibreoptic cables are sometimes used to connect drones and their operators, making them less hackable but limiting their range.
Hardening drones against kinetic attacks is more about agility and tactics. “It’s actually more like an old-fashioned, almost dog fighting-style approach of defence, where you’re trying to make your drones more agile, you’re trying to make them more unpredictable,” Michel says.
The war in Ukraine has shown how difficult this contest can be. The Royal United Services Institute (Rusi) previously estimated that Ukraine was losing around 10,000 drones a month. Quadcopters might last only three flights and fixed-wing drones about six.
Because of that, drones are often designed with the expectation they may not make it back from the front line. The Apache support drones are likely to be far more sophisticated than cheap first-person view systems, so will not be expendable – but they are nonetheless cheaper than a helicopter.
That underscores the problem for drones – defending them against all threats is impossible. “I’m not aware of a future holy grail for securing drones,” says Michel. Military planners instead look to strength in numbers.
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