What did the 2025 swarm test prove?

Introduction

The 2025 Leonidas swarm demonstrations are among the strongest public pieces of evidence yet for the central economic claim behind high-power microwave (HPM) counter-drone weapons: a single engagement can affect many drones at once. In a live-fire event at Camp Atterbury, Indiana, Epirus reported that its Leonidas system disabled 61 of 61 drones flown across five scenarios and culminated the demonstration by neutralising a 49-drone swarm with a single microwave pulse. Observers included representatives from the US Department of Defense, other government agencies and allied nations. [Epirus]epirusinc.comThe live-fire demonstration tested Leonidas against 61 drones across five operationally relevant flight…Read more…

For the broader question of how Leonidas changes drone swarm economics, those results matter because they directly address the “one defender shot versus many attacker drones” problem. However, the demonstrations do not by themselves prove battlefield effectiveness under every operational condition. The tests establish important capabilities, but they also leave several key questions unanswered.

The 61-of-61 and 49-drone claims

The headline result from the August 2025 demonstration was straightforward: Epirus stated that Leonidas successfully disabled all 61 drones flown during five operationally relevant scenarios, producing a reported 100% success rate. The event concluded with a 49-drone swarm engagement in which the company said a single burst of electromagnetic energy defeated the entire swarm. [Epirus+2Semiconductor Today]epirusinc.comThe live-fire demonstration tested Leonidas against 61 drones across five operationally relevant flight…Read more…

The demonstration reportedly included multiple engagement types rather than a single scripted event. According to company descriptions and released footage, the scenarios included:

From an evidence perspective, these results prove several important points.

First, Leonidas can generate real-world effects against flying drones rather than merely laboratory targets. The event involved actual airborne systems rather than static electronics tests. [Epirus]epirusinc.comThe live-fire demonstration tested Leonidas against 61 drones across five operationally relevant flight…Read more…

Second, the demonstrations support the basic premise of microwave-based swarm defence. A successful 49-drone engagement suggests that the system can affect many targets within a single engagement window rather than requiring a separate interceptor for each aircraft. That is the core economic argument behind HPM systems. [Epirus]epirusinc.comThe live-fire demonstration tested Leonidas against 61 drones across five operationally relevant flight…Read more…

Third, the tests indicate that Leonidas is not limited to wide-area effects alone. The inclusion of selective engagements and controlled defeat zones suggests an attempt to demonstrate operator control and discrimination, addressing a common concern that microwave systems are inherently indiscriminate. [YouTube]youtube.comEpirus' Leonidas High-Power Microwave Neutralizes 61-of-61…The Leonidas high-power microwave technology platform is changing th…

Why demonstration settings matter

The strongest interpretation of the 2025 tests is that Leonidas demonstrated a credible one-to-many counter-swarm capability. The weakest interpretation would be that it merely succeeded under favourable test conditions. The reality lies between those extremes.

A demonstration proves what happened under the demonstrated conditions. It does not automatically prove performance across all combat environments.

One major uncertainty concerns the characteristics of the drones used. Epirus stated that the 49-drone event involved two threat-representative drone types, but public reporting provides limited detail regarding exact platforms, electronic hardening levels, autonomy features or survivability measures. [Epirus]epirusinc.comThe live-fire demonstration tested Leonidas against 61 drones across five operationally relevant flight…Read more…

Another question involves swarm geometry. Microwave systems gain their economic advantage when multiple drones occupy a volume of space that can be covered by the system’s energy output. A tightly grouped swarm may be easier to engage than a widely dispersed formation approaching from multiple directions and altitudes simultaneously. Publicly available accounts do not provide enough technical detail to determine how representative the demonstrated formations were of the most demanding combat scenarios. [Epirus]epirusinc.comThe live-fire demonstration tested Leonidas against 61 drones across five operationally relevant flight…Read more…

Environmental conditions also matter. Weather, terrain masking, urban clutter, electromagnetic interference and operational tempo can all affect real-world performance. Demonstrations are valuable because they move beyond laboratory conditions, but they remain more controlled than wartime environments. The 2025 event therefore demonstrates capability rather than establishing an upper bound on combat effectiveness. [Axios]axios.comThe event highlighted a significant advancement in counter-drone technology amid growing global security concerns over drone swarms, whic…

There is also a distinction between disabling and destroying. High-power microwave weapons aim to disrupt or damage electronics. Depending on the target, that may result in immediate loss of control, mission failure, crash, forced landing or degraded operation. Public summaries of the test focus on drones being disabled rather than physically destroyed, which is operationally significant but not necessarily identical to kinetic kill mechanisms. [Epirus]epirusinc.comThe live-fire demonstration tested Leonidas against 61 drones across five operationally relevant flight…Read more…

What the tests mean for swarm economics

The demonstrations are most convincing when viewed through the lens of economics rather than absolute lethality.

Traditional air-defence systems often face a scaling problem: more drones generally require more interceptors, ammunition or engagement opportunities. The Leonidas demonstration suggests that engagement demand does not necessarily increase linearly with swarm size. If one pulse can affect dozens of drones, then the cost-exchange ratio potentially shifts in the defender’s favour. [Epirus]epirusinc.comThe live-fire demonstration tested Leonidas against 61 drones across five operationally relevant flight…Read more…

That does not mean the economics become universally favourable. The attacker still influences outcomes through swarm design, spacing, electronic protection, flight profiles and attack timing. Nevertheless, the 49-drone event provides direct evidence that the one-to-many concept is not merely theoretical. The demonstration’s significance lies less in the exact number 49 than in showing that the engagement model can scale beyond one target at a time. [Epirus]epirusinc.comThe live-fire demonstration tested Leonidas against 61 drones across five operationally relevant flight…Read more…

For military planners evaluating directed-energy weapons, this is arguably the most important takeaway. The test supports the proposition that microwave systems may reduce the saturation advantage that large drone swarms seek to create. [Axios]axios.comThe event highlighted a significant advancement in counter-drone technology amid growing global security concerns over drone swarms, whic…

What evidence would strengthen the case

The 2025 demonstrations are persuasive but not definitive. Several types of additional evidence would significantly strengthen confidence in the system’s operational value.

Independent government test reporting

The strongest corroboration would come from detailed assessments released by military test organisations rather than company summaries. Independent reporting could clarify engagement conditions, success criteria and system limitations. The presence of government and allied observers adds credibility, but publicly available data remain limited. [Axios]axios.comThe event highlighted a significant advancement in counter-drone technology amid growing global security concerns over drone swarms, whic…

More demanding swarm profiles

Future demonstrations involving larger numbers of drones, wider dispersal patterns, mixed autonomy levels or more complex attack geometries would provide a clearer picture of performance boundaries. The key question is not whether Leonidas can defeat a swarm, but how swarm characteristics affect success rates.

Operational deployment evidence

Perhaps the most valuable evidence would be performance data from sustained military use. Systems often behave differently when exposed to continuous operations, maintenance demands, varying climates and adaptive adversaries. Public reporting indicates that Leonidas-related systems have moved into military testing and deployment pathways, but comprehensive operational data remain limited. [DefenseScoop]defensescoop.commarines microwave weapon hpm epirus leonidas expeditionaryMarines to get new drone-killing microwave weapon…Sep 23, 2024 — The high-power microwave weapon prototype, known as Leoni…

Performance against evolving threats

The drone threat continues to evolve. Subsequent Epirus demonstrations against fibre-optic-controlled drones show that the company is attempting to address emerging threat types rather than only conventional radio-controlled systems. Continued testing against new classes of drones will be important because swarm economics depend on whether the defender can keep pace with attacker adaptation. [Epirus]epirusinc.comEpirusEpirus' Leonidas Demonstrates Successful Use of High-…13 Jan 2026 — 2025 · Epirus' Leonidas High-Power Microwave Defeats 49-Dron…

What the 2025 tests actually proved

The most defensible conclusion is that the 2025 Camp Atterbury demonstrations validated the central engineering and economic premise behind Leonidas. The reported 61-of-61 result and 49-drone swarm engagement show that a high-power microwave system can disable multiple airborne drones in a live-fire setting and can do so at a scale that conventional one-interceptor-per-target systems cannot easily match. [Epirus+2Semiconductor Today]epirusinc.comThe live-fire demonstration tested Leonidas against 61 drones across five operationally relevant flight…Read more…

What the demonstrations do not prove is that every swarm, under every operational condition, can be defeated with equal effectiveness. Questions about threat diversity, formation geometry, environmental complexity, survivability against hardened systems and long-term operational performance remain open. The tests therefore provide strong evidence for the one-to-many concept, but they are best understood as a significant proof point rather than a final verdict on combat effectiveness. [Epirus+2Tom's Hardware]epirusinc.comThe live-fire demonstration tested Leonidas against 61 drones across five operationally relevant flight…Read more…

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Endnotes

1. Source: axios.com
   Link: https://www.axios.com/2025/08/28/epirus-indiana-drone-swarm-demo-leonidas
   Source snippet

   The event highlighted a significant advancement in counter-drone technology amid growing global security concerns over drone swarms, whic...

2. Source: semiconductor-today.com
   Title: epirus 300925.shtml
   Link: https://www.semiconductor-today.com/news_items/2025/sep/epirus-300925.shtml
   Source snippet

   Epirus' GaN-based Leonidas high-power microwave system neutralizes all 61 drones in live-fire demo. Epirus Inc of Torrance, CA...Read more...

3. Source: youtube.com
   Link: https://www.youtube.com/watch?v=na0pGfopahM
   Source snippet

   Epirus' Leonidas High-Power Microwave Neutralizes 61-of-61...The Leonidas high-power microwave technology platform is changing th...

4. Source: defensescoop.com
   Title: marines microwave weapon hpm epirus leonidas [expeditionary]({{ ‘marine-variant/’ | relative_url }})
   Link: https://defensescoop.com/2024/09/23/marines-microwave-weapon-hpm-epirus-leonidas-expeditionary/
   Source snippet

   Marines to get new drone-killing microwave weapon...Sep 23, 2024 — The high-power microwave weapon prototype, known as Leoni...

5. Source: youtube.com
   Link: https://www.youtube.com/watch?v=ZrkopSw5uas
   Source snippet

   100% successful against drones flown...

6. Source: youtube.com
   Link: https://www.youtube.com/channel/UCbN5WM_Smgm5AmscysS-e4g
   Source snippet

   EpirusEpirus is a high-growth technology company dedicated to overcoming the asymmetric challenges inherent to the future of national sec...

7. Source: youtube.com
   Title: Drone Swarms Are Here. This Technology Could Stop Them
   Link: http://www.youtube.com/watch?v=unraT22a4zY
   Source snippet

   The US Army's new answer to drone swarms: LEONIDAS...

8. Source: youtube.com
   Title: The US Army’s new answer to drone swarms: LEONIDAS
   Link: http://www.youtube.com/watch?v=GSETxYGrxVw
   Source snippet

   Epirus’ Leonidas High-Power Microwave Defeats 49-Drone Swarm...

9. Source: youtube.com
   Title: Epirus Leonidas HPM: The Premier Counter-Drone Swarm Solution
   Link: http://www.youtube.com/watch?v=gAmSDdK57o0
   Source snippet

   Epirus Leonidas 2025 drone swarm test US-made Leonidas High-Power Microwave Defeats 49-Drone Swarm #airdefense UNITED24...

10. 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-demonstration
    Source snippet

    The live-fire demonstration tested Leonidas against 61 drones across five operationally relevant flight...Read more...

11. Source: tomshardware.com
    Title: Tom’s Hardware High-power microwave system downs 49 drones in [one shot]({{ ‘one-shot/’ | relative_url }})
    Link: https://www.tomshardware.com/tech-industry/high-power-microwave-system-downs-49-drones-in-one-shot-weaponized-electromagnetic-interference-erases-drone-swarms-en-masse
    Source snippet

    electronics warfare company, successfully demonstrated a major advancement in counter-drone technology with its Leonidas high-power micro...

12. Source: epirusinc.com
    Link: https://www.epirusinc.com/electronic-warfare
    Source snippet

    Epirus Leonidas High-Power Microwave: Directed Energy...Leonidas is a solid-state, high-power HPM system, utilizing Gallium Nitride (GaN...

13. Source: Wikipedia
    Title: Epirus Leonidas
    Link: https://en.wikipedia.org/wiki/Epirus_Leonidas
    Source snippet

    Epirus LeonidasThe Leonidas is a high-power microwave (HPM) weapon developed to disable unmanned aerial vehicle (UAV) swarms. It was n...

14. Source: epirusinc.com
    Link: https://www.epirusinc.com/press-releases/epirus-leonidas-demonstrates-successful-use-of-high-power-microwave-to-defeat-fiber-optic-controlled-uas
    Source snippet

    EpirusEpirus' Leonidas Demonstrates Successful Use of High-...13 Jan 2026 — 2025 · Epirus' Leonidas High-Power Microwave Defeats 49-Dron...

15. 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

    Many counter-drone...Read more...

16. Source: Wikipedia
    Link: https://en.wikipedia.org/wiki/Epirus
    Source snippet

    EpirusEpirus is a geographical and historical region in southeastern Europe, now shared between Greece and Albania. Classical Epirus r...

17. Source: sossecinc.com
    Title: epirus inc
    Link: https://sossecinc.com/company/epirus-inc/
    Source snippet

    Phone: 3106208...

6

7

1. Website: https://www.epirussystems.com. Email: aaron@epirussystems.com. Country: USA. Address: 2100 East Grand Avenue

2. Source: epirusinc.com
   Link: https://www.epirusinc.com/
   Source snippet

   Home of Leonidas, the Premier High-Power...Epirus combines the latest in directed energy, long-pulse high-power [microwaves]({{ 'microwaves/' | relative_url }}) (HPM), AI, an...

3. Source: epirusinc.com
   Link: https://www.epirusinc.com/newsroom
   Source snippet

   Jan 13. 2026 · Epirus' Leonidas High-Power Microwave Defeats 49-Drone Swarm, 100% of Drones Flown at Live-Fire Demonstration. Sep 4. 2025...

4. Source: linkedin.com
   Link: https://www.linkedin.com/posts/epirus_epirus-leonidas-high-power-microwave-defeats-activity-7371575751776608256-i0zZ
   Source snippet

   tic interference. “We believe showcasing our weaponized...

5. Source: linkedin.com
   Link: https://www.linkedin.com/posts/epirus_100-successful-6161-drones-disabled-across-activity-7366862288256999424-1WbN

6. Source: linkedin.com
   Link: https://www.linkedin.com/company/epirus
   Source snippet

   EpirusEpirus is a high-growth technology company dedicated to overcoming the asymmetric challenges inherent to the future of national sec...

7. Source: linkedin.com
   Link: https://www.linkedin.com/posts/jenerdrum_61-drones-one-electromagnetic-pulse-zero-activity-7372448959027404803-rnG8
   Source snippet

   49 drones simultaneously. With a single pulse. Total test score: 61...Read more...

8. Source: unmannedairspace.info
   Title: Leonidas disabled all 61 drones across five flight
   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...

Additional References

1. Source: reddit.com
   Link: https://www.reddit.com/r/technology/comments/1ntgl3j/usmade_leonidas_microwave_weapon_takes_down_49/
   Source snippet

   US-made Leonidas microwave weapon takes down 49...Leonidas wiped out all 61 drones in the demo Robotics/Automation techspot.com Epirus r...

2. Source: linkedin.com
   Link: https://www.linkedin.com/posts/gustavo-scotti-di-uccio-18137519_epirus-leonidas-high-power-microwave-defeats-activity-7378746403466051584-GJfO
   Source snippet

   Gustavo Scotti di Uccio's Post30 Sept 2025 —... Leonidas High-Power Microwave Defeats 49-Drone Swarm, 100% of Drones Flown at Live-Fire...

3. Source: newsflare.com
   Link: https://www.newsflare.com/video/792400/jaw-dropping-new-weapon-knocks-dozens-of-attacking-drones-out-of-sky
   Source snippet

   le drone swarms by emitting targeted electromagnetic pulses to overload and...

4. Source: reddit.com
   Link: https://www.reddit.com/r/TankPorn/comments/1h3dyft/[stryker
   Source snippet

   he electronics of an entire drone swarm in SHORAD distance.Read more...

5. Source: facebook.com
   Link: https://www.facebook.com/infotechindi07/posts/%EF%B8%8F-industrialist-anand-mahindra-highlighted-the-leonidas-developed-by-epirus-in-t/1374944311320862/
   Source snippet

   defense company Epirus demonstrated its Leonidas high-power microwave (HPM) weapon. The...Read more...

6. Source: inss.org.il
   Link: https://www.inss.org.il/social_media/innovative-systems-for-neutralizing-drone-and-uav-swarms/
   Source snippet

   Innovative Systems for Neutralizing Drone and UAV Swarms11 Dec 2025 — During the trial, a total of approximately 61 drones were intercept...

7. Source: facebook.com
   Link: https://www.facebook.com/groups/2863649300556204/posts/4103110459943409/
   Source snippet

   On August 26, 2025, at Camp Atterbury in Indiana, U.S....Epirus demonstrated its Leonidas. The system disabled all 61 drones across mult...

   Published: August 26, 2025