TOP ATTACK TANK SHELL vs T-72 +ERA | 120mm XM943 STAFF vs Kontakt-1 | Armour Penetration Simulation

The simulation presents the 120mm STAFF shell's explosively formed penetrator impacting Kontakt-1 explosive reactive armour (ERA) on the roof of the T-72.

The Smart Target-Activated Fire and Forget projectile was an American prototype munition developed for 120mm tank cannons in the late-20th century. The projectile could detect and track targets, then flying overhead and firing an EFP downwards onto the roof of the vehicle. The project was cancelled at the end of the 1990's, but the projectile has lived on in video games such as Battlefield.

TO NOTE:
Due to lack of information and computational constraints, certain aspects of the simulation had to be omitted or approximated, however these aspects should not have a large effect on the overall result:
1. The XM943 STAFF Projectile
Internal diagrams could not be found, so everything inside the shell was approximated, including the EFP. However, seen as the projectile is 120mm in diameter, the EFP cannot be larger than this, so with the thickness of the shell and EFP walls, the diameter of the EFP liner is likely to be around 100mm (it is exactly 100mm in the simulation). The liner material and thickness also had to be assumed, but due to how small the EFP is, it is likely that everything was done to maximise performance, hence the choice of a 4mm Tantalum liner -one of the most ideal materials for an EFP, with a thickness/diameter ratio suiting its high density. The explosive used in the model is Octol, just because it is also found in the American CBU-97 cluster bomb EFPs.

2. Computational Constraints (Velocity and Casing omission)
For the explosive material, a domain needs to be defined, however the mesh within it needs to be relatively fine so it doesnt seep through thin structures. So the explosive domain was only put in a small area around the EFP, and not the whole projectile to minimise the number of elements. However, as the walls of the shell around the EFP are very thin, this caused issues with seep-through and meant the simulation would take weeks to solve. The same issue would occur when the other parts of the projectile would move into the explosive domain (due to the projectile's velocity), hence why both the velocity and casing were omitted. This wouldnt make too much of a difference apart from the EFP coming in at a slight obliquity.

3. ERA
The geometry of the Kontakt-1 was taken from the Soviet armour blog, and its acceleration defined by a variable pressure load based on the Gurney and Flis equations. It is uncertain if the ERA would even detonate when impacted by the EFP, as it is insensitive and mainly meant for shaped charge jets...but its much more interesting if it does detonate.

[SYsimulations]

The projectile velocity should be included, as well as the casing around the EFP, however these were causing computational problems and had to be omitted. The composition of the EFP was also assumed as there was insufficient information available online. See the descrition for more details :)

[fratercontenduntocculta]

I remember being a Tanker and wondering what STAFF stood for. They never removed the STAFF reticle in the GAS, so on every Abrams tank you'll see the STAFF reticle in the GAS but no other switch or control for it.

[_germanikus_]

Just imagine the rest of the Projectile stopping mid air until the explosion finished

[xilano]

Another advantage of STAFF would have been its ability to receive targeting data from friendly helicopters and UAVs. Thanks to the nature of the EFP, it could detonate much further away from the target than even this simulation depicts. Obviously many of the projectile's details are still classified, but it apparently worked pretty well and was only canceled thanks to the budget cuts of the late '90s, and the growing irrelevance of Russian armour.

[Treblaine]

Could this theoretically hit a tank in full defilade so there is no direct line of sight to the tank?

[NotTheCIA]

I'd be interested to see an EFP interact with "heavy" ERA like Relikt or Kontakt 5

[RomanianReaver]

Lotta idiots in the comments.

That's simulating Kontakt-1 ERA. Not dual-layer Kontakt-5 or Relikt or Duplet or anything used this side of 1990.

[DamplyDoo]

Incredibly interesting, thank you for this one

[UraniumEagle]

Please do a video on the process of creating these videos! Would love to see a walkthrough of the software and process behind it.

[Juel]

"Top attack broken, please nerf" - Russia probably

[Klovaneer]

Impressive. Very nice. Let's see how it fares against K-5 that was already in service.

[pniak_]

Thanks, I wanted to see how top attack missiles pen armor

[uniquescorpions]

Well it wasn’t cancelled just because of the cost I bet, because Kontact 5 was being fielded in what, 83-84? So they put that on everything and it have over 25x the original kinetic protection

[antimatter]

In this case a cage on top of the tank would be very effective.

Round would smash into the side of the cage and ruin the electronics before it detonated. Either that or it would detonate higher, the efp would possibly hit the cage and then break up before hitting the ERA.

Would be interesting to see this scenario if you can model it. I've also seen some Russian tanks with cages covered with ERA as well, that would also be an interesting simulation, K5 era+ 5mm mild steel, 1 meter air gap, K5 and finally the roof armor.

Final note is that this like most top attack munitions suffer from the same common issues, price and accuracy. Usually by the time you calculate the amount of kills they achieve they're about as expensive as the tank they're trying to hit. Under ideal conditions a javelin has around a 80% accuracy, when used under actual combat conditions (smoke, panicking/under trained crews, longer ranges, clutter, multiple other destroyed vehicles in area, evening/morning thermals) the accuracy quickly drops below 50%. Then you have to account for soldiers wasting them on bunkers, lightly armored vehicles, systems destroyed before they got a chance to launch either on the frontlines or during missile strikes on storages.

The you need to account for the fact that 50% of hits won't even be a kill, I've seen a javelin hit an engine compartment, where the crew bailed and the tank was possibly recovered afterwards.

So at the end of the day you need around 6 javelins to destroy a single tank. Which is why there's like 1-2 videos from two years of fighting in Ukraine with actual tank kills with hundreds if not thousands of missiles sent to Ukraine.

Even the US army equips only a tiny fraction of their forces with javelins. Too expensive. It's a propaganda weapon more than anything else. You tell the soldiers on the frontlines that we have javelins and himars and leopards 2a6s and Bradley and when the soldier gets there he's given an AK and a shovel to dig trenches...

[AlexanderGee]

It's so odd and unfortunate that we are finally getting the tank war the generals were expecting when this munition was developed.

[LtAce]

I wasn't sure at first but I think I like this sensual voice over you've added. Another excellent video SY, thank you

[yelectric]

An APS that could stop HEAT shells may stop this if the trajectory is right and the velocities line up. EFP carriers are wild.

[Maverick]

You Should try against Kontact 5, it is more of a kinetic round, Kontact 1 is ineffective against it.

[mohammadshehada]

It is interesting that they called it “Fire and forget” With most rounds the gunners would aim at the target and fire and with XM943 the same thing so why they called it FF ?

[d]

Well done gettng the EFP to form correctly!