New air defense exercises by China have highlighted the fierce challenge of mitigating fast-moving drone swarms, a tactic that will likely be used by the US in any Taiwan conflict.
China’s military just conducted air defense drills to test its abilities against drone swarm problems, according to the South China Morning Post (SCMP ) this month. These drills apparently revealed significant difficulties in effectively targeting the small, quick-moving challenges.
In a first round of anti-aircraft artillery launched against a drone swarm, the People’s Liberation Army ( PLA ) was only able to cause 40 % damage, according to a report from a Chinese state broadcaster CCTV.
Tan Xiaolong, from the PLA Ground Force’s 77th Group Army, noted the problems in hitting robots due to their speed, smaller size and ability to change flight paths.
According to the SCMP report, the exercise exemplifies China’s ongoing efforts to improve its drone capabilities by investing in more creative and quick unmanned aerial vehicles ( UAVs ), which are a part of a global effort to create cost-effective countermeasures to the increasingly sophisticated aerial threats.  ,
In an August 2024 Proceedings article, Karl Flynn highlights the cost dilemma defenders face when using high-end systems like surface-to-air missiles ( SAMs) against cheap, mass-produced drones.
Flynn mentions that, as shown by the continuous Ukraine conflict, commercial drones with cameras may charge a few hundred dollars, while an Egyptian Shahed-136 drone deployed by Russia runs at around US$ 20, 000 per unit.
That compares to the cost of short-range Coles like the IRIS-T, which runs at around$ 450, 000 per bullet. Due to this disparity, defenders can immediately reduce their costly weapon arsenals by putting large amounts of cheap drones in front of them.
Flynn notes that algorithms for as” bright shooter” and “intercept sniper” have limitations in countering advanced swarming behavior. He says that the” bright shooter” engine, which includes specific deconfliction, and the “intercept shooter” algorithm, which uses point-of-intercept navigation, struggle with complicated flight activities and require considerable course corrections.
Additionally, Jonathan Bell makes a point in a 2022 Joint Force Quarterly ( JFQ ) article that the scale and coordination of swarms make it impossible for current counter-drone systems to defeat individual or small groups of drones.
Bell claims that conventional techniques, such as kinetic defenses or jamming, are frequently too slow or resource-intensive to handle the large volumes involved. Moreover, he adds the rapid development of drone swarm capabilities, such as the US Replicator initiative, has outpaced innovation in countermeasures, leaving defense systems vulnerable.
The limitations of the most recent defensive measures are revealed by the growing competition between drone swarms and anti-swarm defenses. Growing drones can swarm and outmaneuver already weak defenses more quickly than they can keep up.
Zachary Kallenborn and Marcel Plichta discuss how a drone swarm’s strength comes from its sheer numbers and the complex, decentralized coordination that enables its dynamic adaptation during engagements in a 2024 JFQ article.
According to Kallenborn and Plichta, drone swarms can exploit gaps in defense coverage, saturate interceptors, and even use decoys to confound and drain defenders ‘ resources.
For instance, they claim that drone swarms can launch saturation attacks when numerous drones target a single defense system, causing it to run out of ammunition or energy, leaving its primary targets unprotected.
They add that drone swarms can employ a variety of tactics, such as firing one drone group to a weak defense while another aims at the weakest defenses.
On the other hand, Kallenborn and Plichta claim that using multiple layers of technology and tactics to defend against these swarms. They note that kinetic weapons, like anti-aircraft guns and missiles, can be effective but may become overwhelmed by the swarm’s numbers.
They say that directed-energy weapons, like high-energy lasers and high-powered microwaves, provide a cost-effective and versatile option, but their performance can be affected by environmental conditions and advancements in drone defenses such as protective coatings.
Kallenborn and Plichta note that while spoofing and jamming can interfere with the swarm’s coordination, the drones ‘ growing autonomy and ability to use alternative systems to navigate are limited by the drones ‘ increasing autonomy.
In spite of that circumstance, Daniel Shats and Peter Singer mention in a Defense One article from November 2023 that China is developing its anti-drone technologies to combat US drone swarms, as highlighted at the Zhuhai Airshow last year.
Shats and Singer claim that China Space Sanjiang Group’s LW-30 laser defense system is a key breakthrough that can down small drones several kilometers away with a 30-kilowatt beam. They mention that this system, which reportedly costs around U1.75 per shot, exemplifies China’s focus on cost-effective, directed-energy weapons.
They say China’s HQ-17AE short-range air-defense system, presented by CASIC’s Second Academy, combines missiles, radar and electronic jamming to target multiple airborne threats, focusing on improving early-warning and interception capabilities through its three-dimensional network design.
In addition, Shats and Singer mention that China’s military-industrial complex, led by entities like CASIC, Poly Technologies and CETC, is also developing high-power microwave weapons and autonomous counter-drone systems.
The best putative counter to an expendable drone swarm is another expendable drone swarm, according to Kristopher Thornburg in a December 2022 Proceedings article.
In line with that, Matthias Brust and other authors make mention of counter-unmanned aerial systems (C-UAS ) as a novel strategy for avoiding malicious UAVs ( mUAVs ) in increasingly congested airspaces in a December 2021 article in the peer-reviewed journal Discover Internet of Things.
The idea behind Brust and others revolves around the deployment of a swarm of defensive UAVs (dUAVs ) that work together and independently create a three-dimensional cluster around the ingested mUAV. They claim that this cluster slows down the mUAV’s movement and eventually leads it out of the conflicting flight zone.
Significantly, this system operates independently of GPS, enhancing its resilience against communication loss and other disruptions.
Brust and others note important aspects of the system, such as balanced clustering, which allows for the formation to function even in dynamic circumstances, and the use of local formation control to adapt to real-time threats.
They note that the defense swarm’s modular design comprises patrolling, detection, interception and counter-attack phases that neutralize the mUAV threat.
Brust and others claim that simulations demonstrate that the system can successfully guide and capture hostile drones, but that factors like communication range and UAV stability affect its performance.
They point out that this approach reduces potential collateral damage and offers a scalable and adaptable solution to the rising risk of unauthorized UAVs in comparison to conventional ground-based systems.