US Air Force shoots down drone swarm with THOR microwave weapon

[jameshart]

“non-kinetic, speed-of-light microwave pulses”

Presumably the version that uses kinetic faster-than-light microwave pulses is still classified.

[abracadaniel]

The kinetic slower-than-light microwave pulse is just a guy throwing microwave ovens at drones with a catapult

[Retric]

I recall reading about some microwave or laser weapon which was pulsed to in theory increase effectiveness. Part of the design was using kinetic effects and the sub light speed propagation of pressure waves through the material.

Basically rather than trying to vaporize armor you heat or blast chunks off in rapid succession which can do all sorts of things including creating strong magnetic fields. Which was then possibly more efficient in defeating armor etc.

I can’t find the exact source but this seems related: https://www.nre.navy.mil/organization/departments/aviation-f...

[sidewndr46]

actually the pulses went back in time and killed the systems inventor. So it no longer exists.

[reilly3000]

Shhhh. Don’t want to be on THEIR naughty list.

[moomoo11]

So it basically does an omae wa mou on the enemy?

[AHOHA]

While I’m working mainly on drones/robotics, counter drones is also becoming a big talk with a lot of interest from investors, however, countring drones isn’t that easy, even with latest sensors (sound/visual/Lidar/radar sensors), there’s a lot of false positives when deployed in real scenarios, one trial we tried near an airport, the system we tested caught a lot of birds as drones, you tune it not to detect it, then drones goes undetected. Some systems tries to us AI to study the fly path and find some anomalies and trigger based on that, but so far I didn’t see personally an acurate system that can reliably detect and neutralize. Swarm on the other hand, might be easier given how easy to detect them.

[all2]

There's a lot of electronics on a little drone that all produces a lot of noise. Depending on the control schema it may be dumping a video feed or telemetry to the base station (typically over 2.4Ghz?). There's also an incidental EM footprint put out by the electronics on board. Brushless motors are extremely electronically noisy and shielding is expensive (by weight, aluminum foil works, but to be effective it needs to be wrapped around everything). I'd go hunting for ways to characterize that EM signature at a distance. Do you need to point a big collection dish at the target? Yes, very likely, but it should get you beyond the standard set of false-positive scenarios caused by Not Enough Information (TM).

Can we listen for motor noise broadcast by the brushless motors?

[bandyaboot]

> there’s a lot of false positives when deployed in real scenarios, one trial we tried near an airport, the system we tested caught a lot of birds as drones

Those weren’t false positives.

https://birdsarentreal.com/

[runtime_blues]

Airport is probably a very different environment, though? I imagine that if you have a military installation, you don't mind blasting some birds with RF every now and then (and the birds probably don't mind either).

[rad_gruchalski]

Silly question but is it possible that the army would not care about birds triggering false positives if the weapon can do the work fast enough?

[dist-epoch]

How about trying your tech in Ukraine.

> Russian electronic warfare (EW) remains potent, with an approximate distribution of at least one major system covering each 10 km of front. These systems are heavily weighted towards the defeat of UAVs and tend not to try and deconflict their effects. Ukrainian UAV losses remain at approximately 10,000 per month.

[TheRealPomax]

Did they also trial it against a drone swarm that knew about THOR (which an assailant would) and had put the drones in "not even Faraday mesh" but just a fairly open wire sphere because microwaves are trivially neutralized with a "mesh" that has several inches of space between the wires?

(E.g. wired cages that are already commonly used by drone-operators in the ducting/smoke stack/container/etc inspection business to prevent their $50k industrial drones from crashing into walls/ceilings)

Because a test that doesn't test "what happens when the enemy knows the weaknesses" is not a test.

[themodelplumber]

That promo video has "suck it Iran" written all over it. Right down to the truck launches and drone shapes.

I do admit I wonder about single point of failure with this, so hopefully it's part of some layered strategy. Maybe with some flingy nets, those matrix-barrel guns with like 100 barrels in a grid, eagles trained to swoop down and pick apart the props, etc. etc.

[notatoad]

given the number of actual incidents involving shooting down drones in recent months, it might have been nice to include right in the title that this was a demonstration, and not an actual deployment against an enemy.

[falcolas]

FWIW, it was a practical test, so while it does not presage war for the US, it does prove that this is a real weapon outside of computer simulations.

[barbegal]

Lots of words but not much detail. What I'm interstates to know:

- The effective range of the system, if the range is only 100m or so then you might need a lot of these to protect a larger strategic area.

- How it neutralises the drones, does it overheat certain components or just inject sufficient noise into the system that the flight controller stops working or just disrupt any command signals.

[narigon]

My guess is it just overwhelmems the control. Solving auto-homing sounds like a hard problem and it's more feasible to just have the drone land on the loss of control.

[hn8305823]

> THOR engaged the targets and knocked them out of the sky using its non-kinetic, speed-of-light microwave pulses.

Maybe that's military jargon but in Physics photons definitely carry and deliver kinetic energy.

[zacharycohn]

A kinetic weapon is one that damages the target by smashing into it. Blunt projectiles like rocks, arrows, bullets, etc.

This is a non-kinetic weapon, because it does not damage the target through kinetic force.

[karaterobot]

Yes, I do think the military usage is different than the physicist's usage. I don't think (or at least cannot find) a consistent, hard-and-fast definition, but it seems like they are using kinetic in this sense to mean something that goes boom, and looks cool, and is hard to deny when shown on television. One thing I'm fairly sure about is that they aren't thinking about physics when they use that phrase!

https://en.wikipedia.org/wiki/Kinetic_military_action

[paulddraper]

> photons definitely carry and deliver kinetic energy

Technically correct, practically irrelevant.

Full direct sunlight exerts 1 ounce per 20 aces.

---

Kinetic weapons are bullets, bombs, etc.

As contrasted with chemical weapons, or electromagnetic weapons.

[jameshart]

It’s energy, but is it kinetic energy? The photon’s massless, but it has momentum… so it can transfer kinetic energy, but does it do so kinetically?

More to the point, ‘kinetic energy’ is ‘movement energy’ - energy you possess by virtue of the fact you are moving.

Show me a stationary photon and we can talk about its ‘kinetic’ energy vs. some other kind of energy.

[reilly3000]

microWaves ≠ photons. It just has to mess with the target’s waves with precision chaos.

[otoburb]

>>[the] weapon proved effective in neutralizing multiple targets even though it had never before been tested against the types of drones used in the trial.

Presumably THOR was tested against American and/or foreign-made retail drones, and not foreign military-grade drones. Hardened electronics aren't a new concept.

[sorokod]

May be true, but a lot of the stuff flying over Ukraine is retail. Future conflicts may be similar.

DJIs seem to be popular

https://gagadget.com/en/153538-ukrainian-intelligence-servic...

[DirectorKrennic]

I presume that the Defense Department's experts are well aware of these things. The article is sparse in details. Maybe they did test this new capability on "military-grade" drones, whatever "military-grade" means. Military technology isn't always superior to civilian, commercial technology, as anyone with even a passive familiarity with government acquisitions could attest. Both Ukraine and Russia have resorted to modified commercial drones in the Ukraine war. A North Korean drone was once recovered that was nothing more than a piece of crap with a cheap camera mounted[1]. Really, the only serious and adversarial competitor in the drone space is China.

[1] https://www.cbsnews.com/news/suspected-north-korean-drones-l...

[justapassenger]

Hardening against really high energy pulses adds weight, and quite a lot of it. And flying things don't like weight.

It'll be arms race, as always.

[bitcurious]

> Presumably THOR was tested against American and/or foreign-made retail drones, and not foreign military-grade drones. Hardened electronics aren't a new concept.

So your assumption is that the airforce can’t source a military grade drone to test with?

[awestroke]

Still a good thing that they can stop massively asymmetric attacks (huge number of cheap drones with cheap explosives)

[tracker1]

I would assume any such drones would be larger/heavier and in fewer relative numbers. As such, able to be dealt with by conventional means (surface to air missile defense).

[nonethewiser]

This is so snarky I cant tell if its genuine or mocking.

[smaili]

Do they decide on an acronym first then work backwards to try and come up with what each letter stands for or is it just a coincidence that they landed on THOR? :)

[hammock]

Chatgpt makes this fun and rewarding. How about: Mobile Integrated Countermeasure Radiating Overwhelming Waves Against Virtual Enemies (MICROWAVE)

[jstarfish]

The last time they didn't do this, they ended up carrying MANPADS into battle.

[falcolas]

As they say, "Someone really wanted our initials to spell out 'SHIELD'."

[Taek]

It's called a backronym :)

[AHOHA]

Both way, I did some projects with military and they care much about these acronyms for some reason.

[denton-scratch]

I'd like to know more, like the power of the beam, and what it does to the drones. I'm not wow'ed to learn that an electronic circuit can be influenced by microwaves, nor that a HF radio beam can be jammed. I note the article didn't claim this thing can be used to disable an autonomous cruise missile using inertial/map-based guidance, and having no radio receiver.

[SEJeff]

Let’s also not forget LEONIDAS, which is a bit more mobile but smaller.

https://www.thedefensepost.com/2023/01/24/epirus-counter-dro...

[dmbche]

I wonder if these devices could ever become powerful enough to be mounted on missiles and thrown at helicopters or planes and have them drop out of the sky - or mounting them on Growlers! Could be interesting as an alternative to explosives

[fennecfoxy]

Why call it THOR when it uses microwaves rather than bolts of electricity?

More expensive but I think small, fast drone interceptors would be better. Show them the target and then let the machine guide it there, squirt out some 5 cent netting and the target drone is toast if they use a propellor, if they use some sort of jet then hmm. Just have like 500g of explosive in the interceptor I guess.

[epolanski]

Serious question, what if instead of pointing it to drones it was pointed to organic flesh? Wouldn't that microwave burst the water contained in someone's body?

[rohan_]

Defense engineers have more fun!

[epolanski]

I don't know, I was offered to design and implement military cockpits UI and tracking systems for the biggest weapon exporter in Italy for a very good salary, a 60% raise of what I earned at the time and I was like "no thanks, I want to go sleep without thinking I'm helping writing software to kill people".

Since then I have a very clear clause in my contracts that I don't work in projects involving law enforcement, military and some other business.

[rdtsc]

Very neat. Wonder if drones could fly lower and swarm around it in an almost full circle. There could be anti-THOR suicide drones attacking first before the rest fly in. Then, would any shielding work or even some kind of a microwave energy reflector, like an inverted cone, to concentrate the energy back at the THOR system to use its energy against itself.

[hendersoon]

They say it's a wide beam. Is that a misinterpretation of the spectrum used or did they mean physically a wide beam, as opposed to a thin maser? That would be extremely inefficient compared to a pinpoint accurate defense, wouldn't it? I assume military drones are difficult to spot, so maybe they need a shotgun pellet approach.

[Marlon1788]

I wonder how effective this is against a microwave resistant design. microwaves are incredibly easy to deflect, 1mm sheet steel at the right angles would be interesting to see. 1M USD start up drone company inquire here.

[arcastroe]

According to the article, this anti drone system works by targeting the electronics inside the drone with microwave pulses.

Dumb question: why couldn't the electronics be shielded like the door of your kitchen microwave?

[two_in_one]

anti-drone 'rifles' are used a lot in Ukrainian war by both sides. As I understand they mostly target GPS receivers and force 'disoriented' drone to land. Also there are attacks on control frequencies. Which are countered by frequency changes or hopping, obviously. Attack on drones electronics itself requires significant power. So that thing likely to have short range. AI powered drones, which don't need constant control and GPS, will be much harder to take down. They can be made today for about $1k, more for bigger ones.