Within Microwave Risk
Can One Microwave Shot Stop a Swarm?
A broad microwave footprint can change swarm defence by affecting many drones at once, but only when the formation and timing cooperate.
On this page
- Why swarm size changes the engagement problem
- How a beam footprint can affect multiple drones
- Where one to many defence still breaks down
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Introduction
Yes, under the right conditions a single high-power microwave (HPM) pulse can stop a drone swarm. The key phrase is “under the right conditions”. Microwave counter-swarm weapons are attractive because they do not have to engage each drone individually. Instead, they project electromagnetic energy across a volume of space, potentially disrupting or damaging the electronics of many drones at once. Recent demonstrations have shown dozens of drones being affected in a single engagement, including a widely publicised test in which a microwave system reportedly disabled a 49-drone swarm with one pulse. [Epirus+2Unmanned Airspace]epirusinc.comLeonidas' suite of capability…Read more…
However, a one-shot defeat is not a universal capability. It depends on swarm geometry, drone spacing, flight timing, beam coverage, electronic vulnerability, and the ability of the defending system to place sufficient electromagnetic energy on multiple targets simultaneously. Understanding those conditions explains both the promise and the limitations of microwave swarm defence.
Why Swarm Size Changes the Engagement Problem
Traditional air defence systems are often designed around a one-target-at-a-time model. Whether using missiles, guns, or even many laser systems, each engagement consumes time, attention, and often a finite resource. Swarms exploit this by presenting dozens of simultaneous threats.
Microwave weapons attempt to change the mathematics of the engagement. Instead of asking how quickly a defender can destroy drones one by one, they ask whether a single electromagnetic event can affect an entire cluster of drones. Systems such as the US Air Force Research Laboratory’s Tactical High-power Operational Responder (THOR) were specifically developed as counter-swarm weapons rather than general-purpose air-defence systems. AFRL describes THOR as a system intended to provide non-kinetic defeat of multiple drone targets in a single engagement. [AFRL+2Air Force Research Laboratory]afrl.af.milenemy drone operators may soon face the power of thor“THOR is essentially a high-powered electromagnetic source that we put together…Read more…
This distinction matters because a swarm’s strength comes from concentration. Ironically, that same concentration can create vulnerability. The more tightly grouped the drones are, the more likely they are to occupy the same microwave footprint.
How a Beam Footprint Can Affect Multiple Drones
A microwave counter-swarm weapon does not usually need to strike each drone individually. Instead, it generates a region of intense electromagnetic energy. Any drone inside that region may experience interference, upset, degradation, or permanent damage to critical electronics. [GAO]gao.govScience & Tech Spotlight: Directed Energy WeaponsScience & Tech Spotlight: Directed Energy WeaponsMay 25, 2023 — These weapons include high energy lasers and other high power electrom…
The mechanism is often described as electromagnetic coupling. Energy enters through antennas, wiring, sensors, power systems, or other conductive paths. Once enough energy reaches sensitive electronics, the drone may lose navigation capability, communications, flight control, or onboard processing functions. [GAO]gao.govScience & Tech Spotlight: Directed Energy WeaponsScience & Tech Spotlight: Directed Energy WeaponsMay 25, 2023 — These weapons include high energy lasers and other high power electrom…
For a one-shot swarm defeat to occur, three conditions generally need to align:
- The drones must occupy the beam footprint at the same moment.
- The microwave field must be strong enough across that footprint.
- The drones must be vulnerable enough for the pulse to produce operational effects.
If those conditions coincide, a single pulse can become a one-to-many engagement rather than a one-to-one engagement.
A useful way to visualise the process is to imagine a flock of birds flying through a spotlight. If the spotlight is wide enough and the flock remains tightly grouped, many birds are illuminated simultaneously. If the flock spreads out, only part of it remains inside the beam. Microwave weapons face a similar geometric challenge.
The Demonstrations That Made the Concept Credible
The strongest public evidence for the concept comes from recent counter-drone demonstrations.
In 2025, defence company Epirus announced a live-fire event in which its Leonidas high-power microwave system defeated 61 drones across several scenarios. The most publicised result involved a reported 49-drone swarm neutralised with a single pulse of electromagnetic energy. According to the company, the drones represented multiple threat types and were engaged in an operationally realistic environment. [Epirus+2Unmanned Airspace]epirusinc.comLeonidas' suite of capability…Read more…
Earlier programmes pursued similar objectives. The US Air Force Research Laboratory’s THOR system was developed specifically to defeat multiple drones simultaneously. AFRL reported successful demonstrations against swarm-style attacks, while later tests expanded the scale and realism of swarm engagements. [Tech Briefs+3AFRL+3AFRL]afrl.af.milTactical High-power Operational ResponderA high-powered microwave counter drone weapon, stands ready to demonstrate its effectiveness…
The United Kingdom has also tested high-power radio-frequency systems designed to engage multiple drones within a broad electromagnetic footprint. Public reporting on the RapidDestroyer programme described successful engagements against drone swarms and more than one hundred drones across trials. [Financial Times]ft.comFinancial Times UK tests microwave weapon to disable drone swarmsThis weapon emits a wide beam of radio frequency energy designed to disable or destroy drones by damaging their electronic systems. Durin…
These demonstrations do not prove that every swarm can be defeated with one pulse. They do show that one-to-many engagements are no longer merely theoretical.
Why Tight Formations Are Easier to Stop
The most favourable target for a microwave weapon is not necessarily the largest swarm. It is the swarm whose drones remain concentrated within the effective footprint.
A swarm approaching a defended site often begins as a dense formation because coordination is easier when aircraft remain relatively close together. During this phase, a microwave pulse may expose many drones simultaneously.
As spacing increases, the challenge grows. A swarm spread across hundreds of metres may require multiple pulses, multiple aim points, or multiple systems. The defender’s advantage declines because fewer drones occupy the beam at any given instant.
Timing therefore becomes critical. Operators want to engage a swarm when:
- Drone density is highest.
- The formation is least dispersed.
- The greatest number of targets occupy the footprint simultaneously.
- The swarm has not yet fragmented into separate attack elements.
The same swarm may be vulnerable to one pulse at one moment and largely immune to a one-shot solution a few seconds later simply because of geometry.
Why One-to-Many Defence Still Breaks Down
The phrase “one shot stops a swarm” can create unrealistic expectations. Several factors limit the concept.
Dispersed formations
Swarm designers can deliberately spread drones apart. Wider spacing reduces the number of aircraft exposed to a single pulse and forces defenders to perform multiple engagements.
Hardened electronics
Not all drones are equally vulnerable. Military systems can incorporate shielding, filtering, hardened components, or redundant electronics. Such measures may reduce microwave effectiveness, although they often add cost, weight, and complexity.
Mixed swarms
Future swarms may contain different drone types with different vulnerabilities. A pulse that disables one class of drone may produce weaker effects against another.
Terrain and geometry
Microwave systems generally require favourable line-of-sight conditions. Buildings, terrain features, and other obstacles can complicate engagements and create gaps in coverage.
Power-density limits
A microwave footprint is useful because it covers multiple targets, but spreading energy over a larger area can reduce the energy received by each target. Designers must balance coverage against effect. A beam that is too broad may affect more drones but with insufficient intensity.
These constraints explain why developers continue to emphasise layered defence rather than relying on a single weapon type. [GAO]gao.govgao 23 105868Directed Energy Weapons: DOD Should Focus…17 Apr 2023 — The Department of Defense (DOD) is currently developing directed energy…
What Makes the Concept Strategically Important
The significance of one-shot swarm defeat is less about spectacular demonstrations and more about changing the economics of defence.
Drone swarms seek to overwhelm defenders through numbers. A microwave weapon seeks to reverse that advantage by making numbers less valuable. If dozens of drones can be affected in one engagement cycle, the attacker gains less benefit from simply adding more aircraft to the formation.
That does not eliminate the swarm threat. Instead, it shifts the contest toward formation design, spacing, electronic resilience, timing, and electromagnetic survivability. The most important lesson is not that a microwave pulse can always stop a swarm. It is that swarm designers can no longer assume that numerical mass alone guarantees success.
A single microwave shot can stop a drone swarm when the swarm remains concentrated, enters the weapon’s effective footprint, and relies on electronics vulnerable to intense electromagnetic energy. Recent demonstrations suggest that such one-to-many engagements are achievable in practice. Yet the capability remains highly dependent on geometry, timing, and target characteristics, which is why microwave systems are best understood as powerful counter-swarm tools rather than universal swarm killers. [Tom's Hardware+4Epirus+4AFRL]epirusinc.comLeonidas' suite of capability…Read more…
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Endnotes
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Source: afrl.af.mil
Title: enemy drone operators may soon face the power of thor
Link: https://www.afrl.af.mil/News/Article-Display/Article/2339175/enemy-drone-operators-may-soon-face-the-power-of-thor/Source snippet
“THOR is essentially a high-powered electromagnetic source that we put together...Read more...
-
Source: gao.gov
Title: Science & Tech Spotlight: Directed Energy Weapons
Link: https://www.gao.gov/products/gao-23-106717Source snippet
Science & Tech Spotlight: Directed Energy WeaponsMay 25, 2023 — These weapons include high energy [lasers]({{ 'lasers/' | relative_url }}) and other high power electrom...
Published: May 25, 2023
-
Source: afrl.af.mil
Link: https://www.afrl.af.mil/News/Photos/igphoto/2003223867/Source snippet
Tactical High-power Operational ResponderA high-powered microwave counter drone weapon, stands ready to demonstrate its effectiveness...
-
Source: gao.gov
Title: gao 23 105868
Link: https://www.gao.gov/products/gao-23-105868Source snippet
Directed Energy Weapons: DOD Should Focus...17 Apr 2023 — The Department of Defense (DOD) is currently developing directed energy...
-
Source: epirusinc.com
Link: https://www.epirusinc.com/press-releases/epirus-leonidas-high-power-microwave-defeats-49-drone-swarm-100-of-drones-flown-at-live-fire-demonstrationSource snippet
Leonidas' suite of capability...Read more...
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Source: unmannedairspace.info
Title: epirus leonidas defeats 49 drone swarm with one electromagnetic burst
Link: https://www.unmannedairspace.info/counter-uas-systems-and-policies/epirus-leonidas-defeats-49-drone-swarm-with-one-electromagnetic-burst/Source snippet
Epirus' Leonidas defeats 49-drone swarm with one...2 Sept 2025 — Epirus' Leonidas defeats 49-drone swarm with one electromagnetic burst...
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Source: tomshardware.com
Title: Tom’s Hardware High-power microwave system downs 49 drones in one shot
Link: https://www.tomshardware.com/tech-industry/high-power-microwave-system-downs-49-drones-in-one-shot-weaponized-electromagnetic-interference-erases-drone-swarms-en-masseSource snippet
electronics warfare company, successfully demonstrated a major advancement in counter-drone technology with its Leonidas high-power micro...
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Source: afresearchlab.com
Title: counter swarm high power weapon
Link: https://afresearchlab.com/counter-swarm-high-power-weapon/Source snippet
Air Force Research LaboratoryTACTICAL HIGH POWER OPERATIONAL RESPONDER...Winner of the What's New in Defense 2021 award, THOR is a count...
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Source: techbriefs.com
Link: https://www.techbriefs.com/component/content/article/49907-meet-thor-afrls-counter-drone-that-tracks-and-disables-drone-swarmSource snippet
Meet THOR: AFRL's Counter-Drone that Tracks and...THOR is a high-power microwave counter-drone weapon that the Air Force Research Lab ha...
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Source: ft.com
Title: Financial Times UK tests microwave weapon to disable drone swarms
Link: https://www.ft.com/content/41703199-201e-4702-b34a-a0a633cdfcf5Source snippet
This weapon emits a wide beam of radio frequency energy designed to disable or destroy drones by damaging their electronic systems. Durin...
Published: April 17, 2025
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Source: unmannedairspace.info
Link: https://www.unmannedairspace.info/counter-uas-systems-and-policies/us-army-releases-video-animation-of-high-powered-microwave-technology-designed-to-counter-drone-swarms/Source snippet
US Army releases video animation of high-powered...The system, which shoots high-powered [microwaves]({{ 'microwaves/' | relative_url }}) at unmanned aircraft to disrupt thei...
Published: June 2019
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Source: epirusinc.com
Link: https://www.epirusinc.com/Source snippet
Epirus - Home of Leonidas, the Premier High-Power...Epirus' Leonidas High-Power Microwave Defeats 49-Drone Swarm, 100% of Drones Flown a...
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Source: epirusinc.com
Link: https://www.epirusinc.com/electronic-warfareSource snippet
Epirus Leonidas High-Power Microwave: Directed Energy...Epirus' Leonidas High-Power Microwave Defeats 49-Drone Swarm, 100% of Drones Flo...
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Source: afrl.af.mil
Title: mil AFR L conducts swarm technology demonstration
Link: https://www.afrl.af.mil/News/Article-Display/Article/3396995/afrl-conducts-swarm-technology-demonstration/Source snippet
conducts swarm technology demonstrationMay 16, 2023 — “THOR was exceptionally effective at disabling the swarm with its wide beam, high p...
Published: May 16, 2023
Additional References
-
Source: airuniversity.af.edu
Title: army partners with air forces thor for base defense
Link: https://www.airuniversity.af.edu/News/Display/Article/2511792/army-partners-with-air-forces-thor-for-base-defense/Source snippet
partners with Air Force's THOR for base defenseFeb 23, 2021 — THOR is a prototype directed energy weapon used to disable the electronics...
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Source: aspistrategist.org.au
Title: war at the speed of light the emerging role of directed energy weapons
Link: https://www.aspistrategist.org.au/war-at-the-speed-of-light-the-emerging-role-of-directed-energy-weapons/Source snippet
the emerging role of directed-energy weapons15 Apr 2026 — High-power microwave weapons can be used offensively alongside electromagnetic...
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Source: calibredefence.co.uk
Title: epirus zaps fibre optic fpv with leonidas microwave weapon
Link: https://www.calibredefence.co.uk/epirus-zaps-fibre-optic-fpv-with-leonidas-microwave-weapon/Source snippet
Epirus zaps fibre-optic FPV with Leonidas microwave...28 Jan 2026 — Epirus has developed a microwave weapon called Leonidas that has dem...
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Source: coherentmarketinsights.com
Title: directed energy weapons in counter drone missile defense 3576
Link: https://www.coherentmarketinsights.com/blog/aerospace-and-defense/directed-energy-weapons-in-counter-drone-missile-defense-3576Source snippet
Directed Energy Weapons in CounterDrone Missile Defense4 May 2026 — The high-energy lasers that are being used to defeat any aerial threa...
Published: May 2026
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Source: defence-blog.com
Title: epirus confirms leonidas microwave system integration with dft platform
Link: https://defence-blog.com/epirus-confirms-leonidas-microwave-system-integration-with-dft-platform/Source snippet
Epirus confirms Leonidas microwave system integration...25 Feb 2026 — The combined system links autonomous detection and tracking with n...
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Source: defencefinancemonitor.com
Title: directed energy weapons in 20252035
Link: https://www.defencefinancemonitor.com/p/directed-energy-weapons-in-20252035Source snippet
Directed Energy Weapons in 2025–2035: Development...23 May 2025 — This prototype HPM system, developed under Team Hersa, successfully br...
Published: May 2025
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Source: defencefinancemonitor.com
Title: non kinetic counter uas with high
Link: https://www.defencefinancemonitor.com/p/non-kinetic-counter-uas-with-highSource snippet
Non-Kinetic Counter-UAS with High Power Microwave8 Dec 2025 — Jamming remains the first line of defense due to its simplicity and low cos...
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Source: dronelife.com
Title: microwave counter drone system
Link: https://dronelife.com/2025/10/15/microwave-counter-drone-system/Source snippet
15 Oct 2025 — Epirus and General Dynamics unveil Leonidas AR, a mobile microwave counter drone system designed to defeat drone swarms for...
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Source: dvidshub.net
Link: https://www.dvidshub.net/video/904340/thor-tactical-high-power-operational-responderSource snippet
Thor - Tactical High-power Operational ResponderTHOR is a high power microwave counter-drone weapon that the Air Force Research Lab has d...
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Source: facebook.com
Link: https://www.facebook.com/AFResearchLab/videos/afrls-tactical-high-power-operational-responder-or-thor-system-%EF%B8%8F-is-swarming-int/1138955837220051/Source snippet
AFRL's Tactical, High-power, Operational Responder or...Thor is a high-power microwave counter drone weapon that the Air Force research...
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