Within THOR
What Else Could THOR Affect?
Wide-area microwave effects could help against swarms, but they also raise hard questions about nearby radios, radars, vehicles, aircraft, and personnel.
On this page
- Why wide area effects need safety rules
- Risks to friendly electronics and operations
- How exclusion zones shape real use
Page outline Jump by section
Introduction
THOR’s attraction as a counter-drone system is also its main safety challenge. Unlike a laser that concentrates energy on a single point, THOR uses high-power microwave (HPM) pulses intended to create electronic effects across a broader volume of air. That wider-area approach offers a potential advantage against drone swarms, but it raises a practical question for commanders and airbase operators: what else could be affected when the system fires? Public information on THOR’s exact power levels, frequencies and operating envelopes remains limited, yet the broader experience with high-power microwave systems makes one conclusion clear. Effective use depends not only on defeating hostile drones but also on protecting friendly electronics, nearby operations and personnel through carefully designed safety procedures and exclusion zones. [Air Force Research Laboratory]afresearchlab.comA target is identified, the silent weapon discharges in a nanosecond and the impact…Read more…
Why Wide-Area Effects Need Safety Rules
THOR was developed to disable multiple drones through high-power microwave pulses that produce a “counter-electronic effect” rather than a kinetic impact. The system’s value comes from the possibility that one engagement can affect several targets at once. However, electromagnetic energy does not inherently distinguish between hostile and friendly electronics. Any military deployment therefore has to manage where the beam is pointed, what equipment is nearby and which systems must remain protected during operation. [Air Force Research Laboratory]afresearchlab.comA target is identified, the silent weapon discharges in a nanosecond and the impact…Read more…
Government assessments of directed-energy weapons consistently note that high-power microwave systems operate by interacting with electronic systems rather than simply destroying physical structures. Depending on intensity and exposure, effects can range from temporary disruption to permanent damage. This means safety planning extends beyond the target drones themselves and into the broader electromagnetic environment. [GAO]gao.govgao 23 106717Science & Tech Spotlight: Directed Energy Weapons25 May 2023 — These weapons include high energy lasers and other high power electroma…
For this reason, microwave counter-drone weapons are often discussed alongside electromagnetic compatibility requirements—the discipline concerned with ensuring that one electronic system does not unintentionally interfere with another. A successful deployment is therefore not merely a question of whether the drone swarm is neutralised, but whether critical friendly systems continue operating as intended during and after engagement.
Risks to Friendly Electronics and Operations
Radios, Networks and Command Systems
Military airbases depend on dense concentrations of electronics: communications equipment, data networks, sensors, navigation aids and command-and-control systems. A high-power microwave system intended to couple energy into drone electronics naturally creates concern about unintended coupling into nearby friendly systems.
Publicly available information does not indicate that THOR has caused operational damage to friendly military equipment during testing. Nevertheless, the underlying physics that make HPM weapons effective against drones explain why operators must account for nearby electronics. Microwaves can enter systems through antennas, cables, wiring harnesses and other conductive paths. Sensitive components may experience interference, resets or, at sufficiently high levels, hardware damage. [GAO+2ResearchGate]gao.govgao 23 106717Science & Tech Spotlight: Directed Energy Weapons25 May 2023 — These weapons include high energy lasers and other high power electroma…
This concern becomes more significant on modern bases where radar systems, communications nodes and electronic warfare assets operate in close proximity. A counter-swarm engagement cannot be allowed to disable the very systems required to maintain situational awareness.
Aircraft and Ground Vehicles
Aircraft create a particularly demanding safety problem. Modern military aircraft contain extensive avionics, flight-control electronics, navigation systems and communications equipment. Ground vehicles increasingly rely on networked electronics as well.
Public reporting on newer microwave counter-drone systems highlights that high-power microwave effects are not inherently limited to drones. Manufacturers and observers describe the technology as producing counter-electronics effects that can influence a broad range of electronic devices under appropriate conditions. That reality explains why military users establish controlled engagement sectors rather than treating microwave weapons as universally safe in all directions. [Epirus+2Wikipedia]epirusinc.comEpirusEpirus Leonidas High-Power Microwave: Directed Energy…Leonidas is a solid-state, high-power HPM system, utilizing Gallium Nitrid…
For an airbase-defence system such as THOR, the operational question is therefore not only whether a drone is within range, but whether friendly aircraft, maintenance areas or mission-critical infrastructure lie within the relevant electromagnetic hazard area.
Sensor and Radar Interference
Air-defence operations depend heavily on radar and sensing systems. A counter-drone microwave system that creates strong electromagnetic emissions must be integrated into a broader electromagnetic spectrum management plan.
The challenge is not necessarily permanent damage. Temporary interference, degraded sensor performance or operational disruption at a critical moment may be sufficient to create problems during a defensive engagement. As a result, microwave weapons are generally treated as part of a coordinated system rather than standalone devices operating independently of other sensors and effectors. [GAO]gao.govgao 23 106717Science & Tech Spotlight: Directed Energy Weapons25 May 2023 — These weapons include high energy lasers and other high power electroma…
Human Safety Is Part of the Same Problem
Discussion of THOR often focuses on electronics, but personnel safety is another reason exclusion zones exist. Public sources describing other directed-energy systems show that military organisations already use exposure limits and operational controls when electromagnetic energy could affect people. The well-known Active Denial System, for example, was designed specifically around human exposure to directed electromagnetic energy and required carefully managed operating procedures. [PHR]phr.orghealth impacts of crowd control weapons directed energy devicesHealth Impacts of Crowd-Control Weapons: Directed…Oct 28, 2020 — This technology delivers very high-frequency millimeter-wavelength…
THOR operates in a different part of the directed-energy landscape and serves a different mission, but the broader principle remains the same: personnel should not be exposed to uncontrolled high-energy electromagnetic fields. Exact safety distances for THOR are not publicly available, yet research on high-power microwave counter-drone systems routinely includes exclusion-zone calculations and compliance with electromagnetic exposure standards, illustrating how central safety geometry is to practical deployment. [arXiv]arxiv.orgOpen source on arxiv.org.
The result is a layered safety framework that considers:
- Operators positioned near the system.
- Maintenance personnel working around protected assets.
- Aircrew and ground crews operating in defended areas.
- Civilian workers who may be present on large military installations.
- Nearby electronic medical or monitoring equipment where relevant.
How Exclusion Zones Shape Real Use
The most important governance tool for managing THOR-related risks is the exclusion zone. An exclusion zone is a defined area in which people, friendly equipment or specific activities are restricted when the system is operating.
In practice, exclusion zones are not simply circles drawn around a weapon. They are shaped by factors such as beam direction, terrain, nearby infrastructure, operating frequency, power levels and the sensitivity of protected systems. Because many technical details remain classified, public observers cannot calculate THOR’s exact operational boundaries. However, the need for such boundaries is widely acknowledged across the high-power microwave field. [GAO]gao.govgao 23 106717Science & Tech Spotlight: Directed Energy Weapons25 May 2023 — These weapons include high energy lasers and other high power electroma…
For airbase defence, this creates several operational consequences:
- Pre-planned firing sectors: Operators may have approved engagement directions that minimise exposure to friendly infrastructure.
- Protected equipment zones: Critical communications and command systems may receive additional shielding or separation.
- Coordination procedures: Air operations, maintenance activities and microwave engagements must be synchronised.
- Electromagnetic spectrum management: Microwave weapons become part of the wider process used to manage radars, radios and electronic warfare systems.
These requirements help explain why high-power microwave systems are often described as promising against swarms yet operationally complex. The challenge is not merely generating enough energy to affect hostile drones; it is doing so while preserving friendly capabilities.
Why Safety Constraints Matter to THOR’s Future
The strongest argument for systems like THOR is their potential “one-to-many” effect against large groups of drones. Demonstrations have shown the appeal of microwave approaches when multiple unmanned aircraft must be engaged quickly. [Air Force Research Laboratory]afrl.af.milrl conducts swarm technology demonstrationAir Force Research LaboratoryAFRL conducts swarm technology demonstration16 May 2023 — “The THOR team flew numerous drones at the THOR sy…
Yet the same characteristic that makes microwave weapons attractive also drives their governance burden. Every expansion in coverage area increases the need to understand secondary effects on friendly electronics, nearby operations and personnel. As microwave counter-drone technology evolves into systems such as AFRL’s follow-on efforts and other military HPM programmes, success will depend as much on electromagnetic safety management as on raw counter-drone performance. [Journal of Electromagnetic Dominance]jedonline.comhigh power microwave systems getting much much closer to operational statusJournal of Electromagnetic DominanceHigh-Power Microwave Systems – Getting (Much…24 Jan 2023 — AFRL's Tactical High Power Operational…
For that reason, safety zones are not an administrative detail attached to THOR after the fact. They are a central design and operational requirement. The practical value of a wide-area microwave defence system depends on proving that it can disable hostile drones while leaving the rest of the defended base functioning normally.
Amazon book picks
Further Reading
Books and field guides related to What Else Could THOR Affect?. Use these as the next step if you want deeper reading beyond the article.
Army of None
Strong background on autonomous systems and swarm threats that THOR is designed to counter.
EMC for product designers
First published 1992. Subjects: Standards, Electromagnetic compatibility, Electronic apparatus and appliances, Electric apparatus and app...
Introduction to Electronic Defense Systems
First published 1991. Subjects: Electronics in military engineering.
eBay marketplace picks
Marketplace Samples
Example marketplace items related to this page. Use the search link to explore similar finds on eBay.
Endnotes
-
Source: gao.gov
Title: gao 23 106717
Link: https://www.gao.gov/products/gao-23-106717Source snippet
Science & Tech Spotlight: Directed Energy Weapons25 May 2023 — These weapons include high energy lasers and other high power electroma...
Published: May 2023
-
Source: researchgate.net
Link: https://www.researchgate.net/publication/4229403_Research_on_high_power_microwave_weaponsSource snippet
(PDF) Research on high power microwave weaponsThis structured narrative review analyses how High-Power Microwave (HPM) Directed Energy We...
-
Source: arxiv.org
Link: https://arxiv.org/abs/2602.08477 -
Source: Wikipedia
Title: Epirus Leonidas
Link: https://en.wikipedia.org/wiki/Epirus_LeonidasSource snippet
Epirus LeonidasThe Leonidas is a high-power microwave (HPM) weapon developed to disable unmanned aerial vehicle (UAV) swarms. It was n...
-
Source: phr.org
Title: health impacts of crowd control weapons directed energy devices
Link: https://phr.org/our-work/resources/health-impacts-of-crowd-control-weapons-directed-energy-devices/Source snippet
Health Impacts of Crowd-Control Weapons: Directed...Oct 28, 2020 — This technology delivers very high-frequency millimeter-[wavelength]({{ 'wavelengths/' | relative_url }})...
-
Source: arxiv.org
Link: https://arxiv.org/abs/2311.12809 -
Source: Wikipedia
Title: THOR (weapon)
Link: https://en.wikipedia.org/wiki/THOR_%28weapon%29Source snippet
THOR (weapon)The Tactical High-power Operational Responder (THOR) is a high-power microwave directed energy weapon developed by the Un...
-
Source: Wikipedia
Title: Directed energy weapon
Link: https://en.wikipedia.org/wiki/Directed-energy_weaponSource snippet
Directed-energy weaponA directed-energy weapon (DEW) is a ranged weapon that damages its target with highly focused energy without a s...
-
Source: gao.gov
Link: https://www.gao.gov/video/directed-energy-weapons-dod-should-focus-transition-planningSource snippet
Directed Energy Weapons DOD Should Focus on Transition...DOD spends about $1 billion annually on directed energy--concentrated electroma...
-
Source: youtube.com
Link: http://www.youtube.com/watch?v=r8SYbFQGr-YSource snippet
Epirus Leonidas: High-Power Microwave for Counter-Electronics...
-
Source: youtube.com
Title: Epirus Leonidas: High-Power Microwave for Counter-Electronics
Link: http://www.youtube.com/watch?v=vLA826fH4Vc -
Source: afresearchlab.com
Link: https://afresearchlab.com/counter-swarm-high-power-weapon/Source snippet
A target is identified, the silent weapon discharges in a nanosecond and the impact...Read more...
-
Source: afrl.af.mil
Title: rl conducts swarm technology demonstration
Link: https://www.afrl.af.mil/News/Article-Display/Article/3396995/afrl-conducts-swarm-technology-demonstration/Source snippet
Air Force Research LaboratoryAFRL conducts swarm technology demonstration16 May 2023 — “The THOR team flew numerous drones at the THOR sy...
Published: May 2023
-
Source: epirusinc.com
Link: https://www.epirusinc.com/electronic-warfareSource snippet
EpirusEpirus Leonidas High-Power Microwave: Directed Energy...Leonidas is a solid-state, high-power HPM system, utilizing Gallium Nitrid...
-
Source: epirusinc.com
Link: https://www.epirusinc.com/Source snippet
Epirus - Home of Leonidas, the Premier High-Power...Epirus combines the latest in solid-state, long-pulse high-power microwave systems w...
-
Source: jedonline.com
Title: high power microwave systems getting much much closer to operational status
Link: https://www.jedonline.com/2023/01/24/high-power-microwave-systems-getting-much-much-closer-to-operational-status/Source snippet
Journal of Electromagnetic DominanceHigh-Power Microwave Systems – Getting (Much...24 Jan 2023 — AFRL's Tactical High Power Operational...
-
Source: youtube.com
Link: https://www.youtube.com/watch?v=na0pGfopahM -
Source: epirusinc.com
Link: https://www.epirusinc.com/press-releases/epirus-leonidas-demonstrates-successful-use-of-high-power-microwave-to-defeat-[fiber-opticSource snippet
Epirus' Leonidas Demonstrates Successful Use of High-...13 Jan 2026 — Leonidas is the first EW-based counter-UAS technology to demonstra...
-
Source: epirusinc.com
Title: Tap to unmute.Read more
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
Epirus' Leonidas High-Power Microwave Defeats 49-Drone...10 Sept 2025 — Leonidas neutralized 61-of-61 drones, culminating in a 49-drone...
-
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...
-
Source: afrl.af.mil
Link: https://www.afrl.af.mil/News/Video/?dvpTag=Thor&dvpmoduleid=69743Source snippet
Force Research Laboratory VideoTactical, High-power, Operational Responder, known as THOR... AFRL's THOR Tracks and Disables Drone Swarm"...
-
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...
-
Source: linkedin.com
Link: https://www.linkedin.com/posts/epirus_epirus-leonidas-high-power-microwave-defeats-activity-7371575751776608256-i0zZSource snippet
tic interference. “We believe showcasing our weaponized...
-
Source: milmag.pl
Title: epirus gdls and kodiak unveil the leonidas agv autonomous counter drone system
Link: https://milmag.pl/en/epirus-gdls-and-kodiak-unveil-the-leonidas-agv-autonomous-counter-drone-system/Source snippet
Epirus, GDLS, and Kodiak unveil the Leonidas AGV...24 Mar 2026 — Leonidas AGV offers the modularity and scalability of the Leonidas high...
-
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...
-
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 system emits controlled bursts of high-power microwave energy...
Additional References
-
Source: facebook.com
Link: https://www.facebook.com/AFResearchLab/posts/for-this-techtuesday-we-look-back-at-the-power-of-thor-and-what-that-means-for-n/3271349919568312/Source snippet
For this #TechTuesday, we look back at the power of THOR...The system, known as the Tactical High-Power Operational Responder (THOR), us...
-
Source: kirtland.af.mil
Link: https://www.kirtland.af.mil/News/Photos/igphoto/2000429585/Source snippet
High-Power MicrowavesThe Active Denial System is a counter-personnel, non-lethal, directed energy weapon. Traveling at the speed of light...
-
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...
-
Source: onr.navy.mil
Link: https://www.onr.navy.mil/organization/departments/code-35/division-353/directed-energy-weapons-high-power-microwavesSource snippet
Office of Naval ResearchDirected Energy Weapons: High Power MicrowavesNavy DEWs include systems that use high-energy lasers (HEL) that em...
-
Source: rtx.com
Link: https://www.rtx.com/raytheon/what-we-do/integrated-air-and-missile-defense/phaser-high-power-microwaveSource snippet
Phaser High-Power Microwave System | RaytheonDefending at the speed of light. The Phaser high-power microwave system uses directed energy...
-
Source: youtube.com
Link: https://www.youtube.com/watch?v=0pwv1BOuqN4Source snippet
AFRL's THOR Tracks and Disables Drone SwarmTactical, High-power, Operational Responder, known as THOR, is a high-power microwave counter...
-
Source: youtube.com
Link: https://www.youtube.com/watch?v=QjHGxKb6W1cSource snippet
THOR (Tactical High-power Operational Responder) Destroys...AFRL's THOR (Tactical High-power Operational Responder) is a prototype Direc...
-
Source: youtube.com
Link: https://www.youtube.com/watch?v=X1toVupe_R8Source snippet
U.S. Directed Energy Weapons SystemsThe Government Accountability Office explains what are Directed Energy Weapons and takes a look at ho...
-
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...23 Sept 2024 — The high-power microwave weapon prototype, known as Leonidas Expediti...
-
Source: ndupress.ndu.edu
Title: directed energy weapons are real and disruptive
Link: https://ndupress.ndu.edu/Media/News/News-Article-View/Article/2053280/directed-energy-weapons-are-real-and-disruptive/Source snippet
Energy Weapons Are Real... And Disruptive9 Jan 2020 — DE weapons include high-energy lasers, high-power radio frequency or microwave d...
Topic Tree