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Shaped Charges – Sheet of copper going through 1ft of solid steel (2010) [video]

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Re: Shaped Charges – Sheet of copper going through 1ft of solid steel (2010) [video]

#11

Post by alkonaut »

londons_explore wrote: post #6

This is just a few dollars worth of copper and explosives. Attach it to a few tens of dollars worth of drone. (The cheapest drones are under 10 dollars now). A country could release 1000 of these and direct them at any military target, and they'll do massive amounts of damage at very low costs. Most anti-drone defences can be defeated simply with a redesign of the drone (eg. Use UWB for Comms, and have dual gyros and…

Something that carries say 1kg for any distance, is a pretty significant drone. The Dji Mavic pro can carry 1kg and is around $1k.

> I think the only reason we haven't seen this on the battlefield yet is that we haven't yet had a war between the right countries. But we will.

There are videos every day of Ukrainian drones dropping shaped charges like the Russian RKG-3/1600 from drones.

Ukraine even has special troops specialized in it, the Aerorozvidka (Google for the videos).

The reason they apparently aren’t bothered by anti drone efforts is because the Russian forces don’t seem to have the training and equipment for it, so regular drones work well enough (with selection bias of course - we don’t see the videos of the failed attacks).

It’s clear from that footage what an advantage it is to be able to drop 2 or 3 munitions since you can correct for wind if you miss the first, something you can’t do with a single drop.

The larger octocopters that can carry 5kg or more is probably what you want for the job. Some range, and at least 2 charges to drop.

Re: Shaped Charges – Sheet of copper going through 1ft of solid steel (2010) [video]

#12

Post by formerly_proven »

londons_explore wrote: post #6

This is just a few dollars worth of copper and explosives. Attach it to a few tens of dollars worth of drone. (The cheapest drones are under 10 dollars now). A country could release 1000 of these and direct them at any military target, and they'll do massive amounts of damage at very low costs. Most anti-drone defences can be defeated simply with a redesign of the drone (eg. Use UWB for Comms, and have dual gyros and…

UA is literally dropping anti-tank grenades and other explosives from commercial/civilian drones as we speak.

Re: Shaped Charges – Sheet of copper going through 1ft of solid steel (2010) [video]

#14

Post by ChuckMcM »

londons_explore wrote: post #6

This is just a few dollars worth of copper and explosives. Attach it to a few tens of dollars worth of drone. (The cheapest drones are under 10 dollars now). A country could release 1000 of these and direct them at any military target, and they'll do massive amounts of damage at very low costs. Most anti-drone defences can be defeated simply with a redesign of the drone (eg. Use UWB for Comms, and have dual gyros and…

And you have just described the AeroEnvironment Switchblade 600 drone. According to Drive they haven't actually been deployed in Ukraine yet but they are on the list apparently. The smaller 300 has been deployed apparently but it doesn't carry a shaped charge, instead it carries an antipersonnel charge. More of a flying hand grenade kind of deal.

Re: Shaped Charges – Sheet of copper going through 1ft of solid steel (2010) [video]

#15

Post by Vladimof »

giantg2 wrote: post #7

If you're going to play around with explosives, an old knowledgeable teacher is best. I imagine incompetence gets weeded out early. The guy in the video has been in quite a few others too. It's fun to see how the hosts are usually a little nervous and he's calm as can be.

This type of explosive is very stable... nothing like nitroglycerin ...

Re: Shaped Charges – Sheet of copper going through 1ft of solid steel (2010) [video]

#16

Post by daenz »

I'm not sure I fully understood the explanation. So the copper cone is turned inside out and turns into a pointed wire that drives into the target? How is it that this wire can continue through the 1ft of steel? Is the force of the explosion flowing through this wire/tube, like liquid in a straw? And somehow it can sustain this through 1ft of steel?

Re: Shaped Charges – Sheet of copper going through 1ft of solid steel (2010) [video]

#17

Post by Vladimof »

londons_explore wrote: post #6

This is just a few dollars worth of copper and explosives. Attach it to a few tens of dollars worth of drone. (The cheapest drones are under 10 dollars now). A country could release 1000 of these and direct them at any military target, and they'll do massive amounts of damage at very low costs. Most anti-drone defences can be defeated simply with a redesign of the drone (eg. Use UWB for Comms, and have dual gyros and…

Did you just upgrade the Slaughter bots? https://www.youtube.com/watch?v=HipTO_7mUOw

actually I think that you didn't because slaughter bots are trying to not cause any collateral damage

Re: Shaped Charges – Sheet of copper going through 1ft of solid steel (2010) [video]

#19

Post by trhway »

daenz wrote: post #16

I'm not sure I fully understood the explanation. So the copper cone is turned inside out and turns into a pointed wire that drives into the target? How is it that this wire can continue through the 1ft of steel? Is the force of the explosion flowing through this wire/tube, like liquid in a straw? And somehow it can sustain this through 1ft of steel?

due to the copper cone shape and the explosion wave propagation from the back the copper, which at those pressures is flowing like a liquid, is formed into a jet and pushed forward like a water in a power washer hose. Water at 3000bar would cut several inch steel (https://www.youtube.com/watch?v=quL14Csmi_Y). The copper in that explosion gets accelerated to the speeds of like 10km/s and as a result cuts through everything in its way.

A bit of current context - beside deep penetration the jet isn't that destructive to surroundings. And here comes design flaw of Russian tanks - getting inside a Russian tank such jet frequently hits the tank's ammo which in those tanks is stored in a carousel around/under the turret and thus it results in the whole tank ammo explosion which even throws the multi-ton turret several stories up into the air (you can see a lot of the tanks blown up in that way - 'lollypops' - in Ukraine). To compare - US Abrams tank has ammo stored in separate compartment in the back of the turret.

Re: Shaped Charges – Sheet of copper going through 1ft of solid steel (2010) [video]

#20

Post by nine_k »

daenz wrote: post #16

I'm not sure I fully understood the explanation. So the copper cone is turned inside out and turns into a pointed wire that drives into the target? How is it that this wire can continue through the 1ft of steel? Is the force of the explosion flowing through this wire/tube, like liquid in a straw? And somehow it can sustain this through 1ft of steel?

Update: this is incorrect.

The cone becomes very hot stream of molten copper. It melts through the steel plate, much like a jet of hot water melts through a block of ice.

This happens fast enough that much heat does not have the time to escape from the impact site, despite high thermal conductivity of metals. The high pressure created by the explosion keeps the jet compressed from sides, too, so it does not fragment easily.

Various kinds of "active armor" trigger the munition by a thinner layer of metal well ahead of the real thick armor plate, then produce counter-explosions to break the jet.

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