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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]

#181

Post by dragontamer »

nyolfen wrote: post #172
dragontamer wrote: post #168

Earlier quoted context omitted.

> "220 mm penetration of RHA" which is plenty for top armor I seriously doubt that. Almost all modern tanks have reactive-armor on top. There's a reason why NLAW has 500+mm penetration AND top-down. NLAW is single-charge (no-tandem), to punch-through reactive armor requires a lot more penetration. Let alone lol Javelin with top-down, 900mm+ penetration, and tandem charge. I don't think 200mm or even 400mm is consider…

you should tell that to the RU tanks getting their lids popped: https://youtu.be/tI5ABZPw9Us not sure about nlaw but javelin also features a side targeting mode

> you should tell that to the RU tanks getting their lids popped:

And you should tell that to USA's and Britain's military, which have chosen 400mm penetration (AT4), 500mm top-down penetration (NLAW), and 900mm top-down + tandem penetration (Javelin).

200mm, even top-down, is significantly less than other anti-tank weapons. I presume that the militaries who made these modern weapons know what they're doing.

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

#182

Post by jade-m »

hunter-gatherer wrote: post #136

In the US/Iraq war such contraptions were commonly referred to as EFPs (explosively formed penetrators). My platoon was once hit by a four-array EFP that was hung behind a cement wall (US forces would often line streets with barricades like this) so we couldn't see it. It went through the concrete wall, the humvee, and took some legs with it. Brutal things they were. We avoided prolonged truck excursions, but I remem…

I think you mean the US invasion of Iraq

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

#183

Post by dragontamer »

nradov wrote: post #146
dragontamer wrote: post #68

Earlier quoted context omitted.

Sure, but Javelins (considered a very reliable weapon), is top-down AND 8kg of tandem charge of 900mm+ penetration. I think NLAW is ~500mm of penetration and top-down. Its not too hard to make a top-down weapon these days, but it does add weight to the device. -------- EDIT: I'm pretty sure that you can't just "drop" a mortar or AT4 warhead reliably either. You'd want to make it into the shape of... well... a bomb. S…

Mortar rounds are already the correct shape with fins to stabilize the flight path. Various irregular and insurgent forces have already weaponized the larger consumer drones with a rack that can release a single mortar round straight down. If the drone is hovering and there isn't much wind then the mortar round will fall straight down and detonate on impact. In some cases they may also have made minor modifications t…

> If the drone is hovering and there isn't much wind then the mortar round will fall straight down and detonate on impact.

Dive bombing. These drones should be dive bombing. WW2 strategy to increase precision and placement of the bomb.

Only lesser-trained pilots glide-bombed or otherwise avoided dive-bombing in WW2.

I don't think the let-go at height maneuver is historically considered very good. By dive bombing, you set forward-momentum on the bomb and more accurately place it, compared to dropping it from a hover. The bomb also reaches its target faster, and the pilot has the ability to line-up the shot (especially useful if the enemy is a moving target).

I'm very much unimpressed by the "let go at height" videos, its just not good piloting IMO. But if these drones were dive-bombing instead, maybe I'd have a bit more respect. I'm not necessarily saying that the pilots have to dive-bomb, but maybe an AI could control that kind of pass.

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

#184

Post by GartzenDeHaes »

chemeril wrote: post #122
GartzenDeHaes wrote: post #113

Earlier quoted context omitted.

A plasma technically. And it doesn't exactly penetrate, it pushes the steel atoms aside very literally like sticking your finger in butter. Edit: obviously it penetrates, but not in the way that you would expect.

Certainly not a plasma. It's a coherent spear of hydrodynamic copper, not a bunch of charged ions floating around.

As far as I know, it could be little qanons in there stealing the steel atoms to build jfk jr's moon rocket. However, the principle physicist for the nuclear emergency search team described it using the butter analogy.

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

#185

Post by jakear »

jade-m wrote: post #182
hunter-gatherer wrote: post #136

In the US/Iraq war such contraptions were commonly referred to as EFPs (explosively formed penetrators). My platoon was once hit by a four-array EFP that was hung behind a cement wall (US forces would often line streets with barricades like this) so we couldn't see it. It went through the concrete wall, the humvee, and took some legs with it. Brutal things they were. We avoided prolonged truck excursions, but I remem…

I think you mean the US invasion of Iraq

Vouched for this. Names are important, it’s disingenuous to suggest US and Iraq played an equal role in initiating the engagement.

Do we call it the Russia/Ukraine war or the Russian invasion of Ukraine?

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

#186

Post by IMTDb »

jakear wrote: post #185
jade-m wrote: post #182

Earlier quoted context omitted.

I think you mean the US invasion of Iraq

Vouched for this. Names are important, it’s disingenuous to suggest US and Iraq played an equal role in initiating the engagement. Do we call it the Russia/Ukraine war or the Russian invasion of Ukraine?

We call them : The Iraq War (https://en.wikipedia.org/wiki/Iraq_War) and the Russo-Ukrainian War (https://en.wikipedia.org/wiki/Russo-Ukrainian_War)

This is a discussion about a special kind of explosive and a first hand story on how it is used in a conflict. Leave politics aside.

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

#187

Post by tomcam »

hunter-gatherer wrote: post #136

In the US/Iraq war such contraptions were commonly referred to as EFPs (explosively formed penetrators). My platoon was once hit by a four-array EFP that was hung behind a cement wall (US forces would often line streets with barricades like this) so we couldn't see it. It went through the concrete wall, the humvee, and took some legs with it. Brutal things they were. We avoided prolonged truck excursions, but I remem…

No post body was provided.

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

#188

Post by MertsA »

nyolfen wrote: post #166
tootie wrote: post #139

Earlier quoted context omitted.

Great video on the engineering of the Javelin and why it's so simple and effective: https://youtu.be/SUdHzKRiBX8 The Javelin has multiple tricks up its sleeve to defeat sophisticated armor and Russian armor is just behind the curve. It's a literal arms race to add more layers of defense and more layers of attack and right now, NATO is far ahead.

this is compounded by the fact that much of the armor on the ground in ukraine does not actually seem to feature the advanced defenses developed during the soviet era, like ERA. i've seen several photos of what appears to be decoy ERA on destroyed t-72's, which was nothing more than a hollow brick of steel. i suspect graft or a weak economy is the reason.

Forget decoys, some of the videos coming out of Ukraine were showing plenty of Russian tanks with the bags for the reactive armor sagging down clearly only holding the spacers and no ERA plates. It's like the troops believed the cover story that they were only going near the border for a training exercise.

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

#189

Post by earthbee »

hunter-gatherer wrote: post #136

In the US/Iraq war such contraptions were commonly referred to as EFPs (explosively formed penetrators). My platoon was once hit by a four-array EFP that was hung behind a cement wall (US forces would often line streets with barricades like this) so we couldn't see it. It went through the concrete wall, the humvee, and took some legs with it. Brutal things they were. We avoided prolonged truck excursions, but I remem…

EFPs are similar but distinct from shaped charges. Shaped charges use a conical liner that forms a jet that is only really effective over a limited range, the liner on EFPs is usually flatter and is designed to form a projectile that is effective over much wider ranges.

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

#190

Post by bawolff »

somenameforme wrote: post #177
Retric wrote: post #145

Earlier quoted context omitted.

Depends on how often you role the dice not just how bad the dice are. Someone that’s got a 1% chance of dying every fireworks show is extraordinarily bad at their job. But if they only put on 2 shows a year they have better than even odds of surviving a 40 year career.

The odds there are surprisingly high, but not better than even. 44.75%

But the important odds in this situation is not the individual, but the group - if you start with a group of 100 (or whatever) people extraordinarily bad at their job, what is the probability at least 1 makes it 40 years.

Survivorship bias is a bias because the sample is biased - Its when you pick a group of people who have already won and then are surprised that they beat the odds and won because you confuse the probability that a specific person wins with the probability that at least 1 person wins.

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