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Yes, but kinetic countermeasures scale really badly. The definition of "drone" is also quite flexible here, a couple guys with shotguns, falcons, or your own anti-drones work fine against a few slow drones, badly against a few dozen slow flying drones, not at all against a few hundred slow flying drones, are essentially useless against one jet-powered drone (microjet engines are very cheap!) don't have a hope against a dozen fast flying drones, and are non-existent to a few hundred fast flying drones.

You'd pay around 2500$ for a 60lbf jet engine, and around 3000$ tops for the rest of the drone. That's around 5500-6000$, so for a hundred drones you'd pay 600 000$, or about 60% of the cost to train one soldier, and around one 0.8 millionths of the yearly US defence expenditure. For 100 drones. That means with the US defence budget you could make 120 000 000 such drones.

Sure, against the current crop of electric consumer drones, it's not much of an issue. But there's the tech to make a 500km/h drone that's fully autonomous and encased in a Faraday cage for less than 10 000$ a piece. That scares the crap out of me.



Bigger isn't necessarily better, here. There's a term for "small jet turbine powered autonomous suicide drone" already - "cruise missile" - and it's something that the US military has put a lot of work into stopping.

Small drones aren't really part of the same threat profile, near as I can tell.


Cruise missiles generally have a diameter of around 70+ cm and a length of over 5 meters. They are also hideously expensive. These drones would have a diameter of around 15-25 cm, a length of a meter or two, a cost a hundredth of a cruise missile. Not comparable.

They're not bigger than a large camera drone, they're just much faster.

The US military has absolutely nothing that can stop a legion of a thousand or more "mini cruise missiles" such as these. Not a chance in hell.


Cruise missiles currently target large things, these would be anti-personnel drones. I guess we could call them “knife missiles”?


I take it that's a culture reference, if it isn't then congratulations, you are in good company.



Umm people speak about lasers, energy based weapons and etc and etc. That problem was solved almost century ago. Flak cannons. The moment you have means to properly detect such cloud of problems, few flak cannons will rip them apart in seconds.


Low flying targets are hard to hit with flak I think. It's also hard to fire flak over the heads of a crowd at a public speaking event without hurting anybody.


No they wouldn't. Flak cannons don't work very well against low flying targets, they tend to just kill everyone on the ground.

Morso, flak cannons are less effective against small targets due to a smaller amount of debris.

Finally, there's no reason for the drones to be that close together. You can have them 30 meters apart , flying at an altitude of 20 meters or so. What then?

Finally, there's targeting. How are you going to target reliably a threat you've never seen before that's a similar size to a lot of birds?


For a state backed terrorist organization, the cost of drones could be even lower. Mass production and very low complexity of engineering will make it easy and cheap to produce drones. Add to that, the cost of failure and innovation is also very less, consequently, the use of drones will increase exponentially.

Just imagine what destruction a terrorist can create if he can launch a 100 drones, from miles away, to attack a filled stadium.


This drone craze is all because we have better batteries today. They should have thought of that when they invented such dangerous tech. /s (Law of unintended consequences)


In my layman opinion the correct solution would be a directed-energy weapon. The most obvious one that comes to mind would be a laser (or an array of lasers, for your dozen-fast flying drone scenario). Imagine the large collection of lights that point multi-directionally behind rockstars at concerts; except, in the future, these are all defensive lasers to defend against a worst-case scenario. Ha, would probably be very impractical except for defending heads of state and the like.


There're relatively easy countermeasures against that too: reflective paint and a rolling airframe. To be effective the laser needs to heat the airframe fast enough to cause structural damage before the energy is dissipated away. This is relatively easy when you're targeting a black plastic drone that remains stationary in the sky. It becomes orders of magnitude less effective when the drone is white or metallic and the point of contact moves all over the drone, particular because flying objects have natural air cooling to dissipate energy away.


Lasers have been demonstrated strong enough that those countermeasures are insufficient.

Bigger problem is, if you’re a politician and this scenario plays out during a rally, you just blinded your own supporters by shining a metal-melting laser at a shiny bauble while it was just above their heads.


I haven't seen any demonstration of a laser destroying a rolling airframe with reflective coatings. The only practical demonstration I could find anywhere was a laser on a boat burning one single drone that was gray in color, from only about 800m away. And it took about ten seconds to do so.

Anyways, I'd love your source.


I think I know the demo you’re talking about.

Most of my search results today are CGI propaganda pieces, the closest I can find is this from 2013, which is just a normal non-shiny and probably non-spinning missile, but from 1.5km and being destroyed 4s after launch: https://youtu.be/kgUnDeED9MM


Maybe the best anti drone would be a swarm of drones you send off to crash into another drone? You could model the schooling from fish or birds, then just have enough of them fill the air with enough density to guarantee a hit of the target within the error of the range finding technology.


The problem is logistics. For this solution to work, the counter swarm should be more capable than the incoming swarm (faster, more AI capabilities, etc), and their quantity should be more than the incoming swarm.

You cannot have millions of drones everywhere, but the enemy just has to be lucky and send a million drones to attack you.

Also, you can have advanced tactics, like releasing the swarm, but programming them to hide and attack at random. With a good enough drone, you can create a almost impossible to evade booby-trap. Especially if you are in a war field.


The counter swarm can be cheaper/worse in some dimensions.

Smaller batteries since they don't need to travel far.

Nets or or even nothing instead of explosives, they need to stop drones not people.

The above two mean a lighter air frame.

The above 3 all mean more speed with the same motors (probably good) or less capable motors (seems like a bad plan).

Communications only need to be short range. Autonomy is plausible (but requires solving friendly fire).


Communications can be jammed.

Counter drones like anti-missile missiles need to be bigger than one would think and require much more energy, because they need to be much faster and more maneuverable than the drones they are hitting. That means bigger motors, higher discharge batteries, and a stronger airframe.

I'm fairly certain they would be more expensive than the attackers drones, and you would need around two orders of magnitude more of them than the attacker.


Why can't shotguns be automated. Building a personal "anti-aircraft/drone" gun should be feasible.


They are. They're usually called CRAM or CIWS on ships (Close in weapons system).[0] They are used as the last line of defense on modern warships against missiles and other threats.

Here you can see one of them in action:

https://www.youtube.com/watch?v=KsVUISS8oHs

[0] https://en.wikipedia.org/wiki/Close-in_weapon_system


They are also ineffective against more than a handful of threats.

They work okay against mortars and dumb munitions, though.




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