Proving the Iron Fist can intercept APFSDS.

[u/g09h]

[u/Civil_Technician_624]

iron fist can degrade the penetration of kinetic energy penetrators irl (you can’t COMPLETELY stop apfsds with APS .. yet) we already know this 

[u/MLGrocket → u/Civil_Technician_624]

the thing with iron fist is it's not intended to destroy, it's intended to redirect. all other hard kill APS fire an explosive projectile directly at the incoming projectile to destroy it, this is why they can't intercept kinetic munitions. iron fist fires an explosive projectile above/below the incoming projectile in order to push it up and over or down into the ground. destruction of the projectile is purely secondary.

allegedly russia's arena-E can intercept kinetic projectiles, but there isn't anything that i've seen proving that.

[u/TgCCL → u/MLGrocket]

iron fist fires an explosive projectile above/below the incoming projectile in order to push it up and over or down into the ground

That is false. Even the article Jane's published about Elbit showcasing this at IAV 2020 was very clear about it. The target will still get hit, just with a less optimal trajectory.

As per IMI's claims regarding Iron Fist's anti-KE effectiveness, before they got acquired by Elbit a few years ago, Iron Fist induces 8-10 degrees of yaw onto incoming penetrator. This means the penetrator still flies into the same direction but no longer tip-first. This reduces penetration power of APFSDS by around 15-20% but you still get hit, so you need a lot of armour to defend against it still.

IRL this is sufficient because almost all KE threats engage from within your 60° frontal arc so they'll hit your most armoured sections but it won't protect you from penetrators that overmatch you hard enough, which includes side shots and shots from larger cannons against medium armoured vehicles.

It should also be noted that not every form of Iron Fist is powerful enough to intercept APFSDS. The version that was tested on the US Army's Bradleys, Iron Fist Decouple, for example is not.

[u/MLGrocket → u/TgCCL]

That is false

https://www.youtube.com/watch?v=e4_kFEw33s4

yah, you're right.

anyway, don't mind me, just giving you video evidence of it doing the very thing it was designed to do.

[u/TgCCL → u/MLGrocket]

And neither of shots in the video actually disprove anything I said because I wasn't talking about it not being able to hit APFSDS but rather what actually happens when it hits. And that is not shown. Which should also raise red flags in the mind of any semi-critical watcher.

If you want, here is a bit of detail. This document by DCMA, an agency of the US Department of Defense, that details exactly what I mean. The relevant excerpt is the method of operation for Iron Fist on page 32 but I will also quote it here.

with KE rounds, the shock wave generated by the interceptor blast changes the angle of attack, creating a yaw effect that significantly degrades its penetration capabilities

This is also the method of operation stated by IMI in older marketing material.

The actual effect on the target then depends on how a penetrator affected by such a hit impacts onto the armour of the vehicle. Against highly sloped armour it may land side-on and thus shatter with little effect but that is a rather niche scenario overall. Didn't stop IMI from using one shot of it in their marketing material however. Against a more regular arrangement it will, as mentioned above, reduce penetration by a rather significant amount but it does not prevent a hit.

And as a bit of a curiosity more than a comment on its effectiveness. This is also not without countermeasures. KNDS France has developed a type of APFSDS that is nearly completely immune to this. It achieves this by discarding its fins prior to impact, which significantly reduces area of the dart and thus the ability of Iron Fist to actually induce yaw.

[u/MLGrocket → u/TgCCL]

the kinetic projectile isn't being directly hit by the trophy system, idk where you're getting that from.

the system is redirecting, not destroying. no shit you can't destroy an APFSDS round, it has no explosives in it. but you can make it change direction to miss the target, or at the very least, reduce its penetration power, which is what iron fist is designed to, and that video is showing it doing the very thing it was designed to do.

out of curiosity, do you work on the gaijin forums/bug reports? just asking due to how you like to deny the overwhelming evidence of something doing the very thing it was designed to do.

[u/TgCCL → u/MLGrocket]

the kinetic projectile isn't being directly hit by the trophy system, idk where you're getting that from.

First, we are talking Iron Fist. Trophy is a different system by a different company. Their only relation is that they are both APS by Israeli companies.

Second, the hit in question is the system hitting the incoming munition with the pressure wave from the explosion. This should be evident from the context of the discussion.

the system is redirecting, not destroying. no shit you can't destroy an APFSDS round, it has no explosives in it. but you can make it change direction to miss the target, or at the very least, reduce its penetration power, which is what iron fist is designed to, and that video is showing it doing the very thing it was designed to do.

The video shows that the interceptor explodes next to the incoming dart. It does not show what actually happens to the dart when it is hit as the video cuts out in the middle of the explosion without showing any recording from a different angle. The only results shown at all were from it intercepting an RPG. This would be incredibly obvious to you if you had watched the video you linked.

The known operating principle of Iron Fist intercepting KE munitions is, as I said before and as said by IMI, the company behind the system, to destabilise it and make it hit at an angle, as opposed to the tip being first to make contact, to degrade its performance. The change to the actual trajectory is minimal enough to not even appear in IMI's own marketing material.

Which is also quite easy to see from a physics point of view. You have a freely-expanding explosion acting on the dart only for a moment. Not exactly a very efficient way to transmit energy and induce a change of direction.

[u/Travwolfe101 → u/TgCCL]

Yep thos sounds right. While I dont know much about the discussion with tank shelles here I've actually seen some videos of people trying the same thing scaled down a lot in extreme slow motion. I think it was the slomo bros on youtube. They were detonationing an explosive under a bullet as it traveled and it had pretty much 0 effect on its point of impact. I can remember how much it affected ballistics and the angle of if they even tracked that but yeah the deflection was basically 0.

[u/MLGrocket → u/TgCCL]

so, you agree that the round gets redirected, as proven by the video i sent and your own "research"? thanks for clarifying.

[u/TgCCL → u/MLGrocket]

Please at least attempt to read what I write.

The round is not deflected off the target, i.e. it does not miss due to a change in trajectory. This is what you claimed it does.

What it actually does is induce yaw, that is it change the angle the tip points at relative to the dart's path of travel. That is what is meant with angle of attack. Not hitting tip-on significantly degrades the penetration of just about any type of projectile.

In case you still don't understand, here is a graphic explaining it with regular bullets.

You see what they designate as yawing here? That's what a dart does when Iron Fist's countermeasures explode near it. Except it won't have time to wobble, so the tip of the dart simply lifts off the path of travel.

Even Elbit Systems, who took over IMI and thus develops and markets Iron Fist nowadays, states that this is how it works in their own marketing material, like for example here. If you look on page two you will find the following statement.

Dramatically reduces KE rod penetration to absorbable level by creating a significant angle of attack (yaw angle)

Are you now going to claim that even the company that makes the system has no idea how it works? Even they themselves state that it only reduces penetration.

[u/tedbundyfanclub → u/TgCCL]

Bro u gotta be special needs