u/EaRLyHawk924

Reading the comments under the posts, I noticed that some players may have not entirely correct ideas about the M829A3 APFSDS, which will be added to the game in tomorrow's update. So I decided to make a short post briefly explaining which APFSDS rounds can be effective against which ERA, and which cannot. In the future, one can refer to this post for explanations.

TL;DR:

The M829A3 is not a universal armour-defeating round. It was specifically engineered to counter older Soviet anti-kinetic ERA like Kontakt‑5 by using a sacrificial nose cap that triggers the explosive layer and allows the main penetrator to pass largely intact. However, against modern Russian Relikt ERA - found on the T‑90M, T‑80BVM, and T‑72B3 - this trick no longer works. Relikt is a dual‑stage system designed to defeat such precursor rods, so the M829A3 performs about as poorly as the DM53 against it: expect frequent non‑penetrations or unreliable results. In practice, do not assume the M829A3 will slice through top‑tier Soviet armour; against Relikt, you still need careful aim and often a second shot.

The common misconception in the War Thunder community is that all Explosive Reactive Armor is created equal, and that a single, high-penetration round should perform uniformly against any ERA array it encounters. In reality, the philosophy behind ERA development diverged sharply between the Eastern and Western blocs, and understanding this split is the key to understanding what the M829A3 can and cannot do in the upcoming update. NATO ERA systems, such as the American ARAT or the Israeli Blazer, yada-yada, were almost exclusively designed to counter chemical energy penetrators like HEAT warheads and ATGMs. This was a doctrinal choice; Western planners assumed that chemical penetrations munitions would be the primary threat to heavy armor, while kinetic protection was to be handled by the composite armor layers built into the hull itself. Conversely, the Soviet Union and its successor states followed a different path, opting to keep the base hull of their mass‑produced MBTs relatively consistent - so as not to retool production lines every three to five years - while dramatically enhancing protection through supplementary bolt‑on systems, like ERA or APS. Starting with Kontakt‑5, Soviet ERA took a radical turn by explicitly engineering their reactive armour complexes to disrupt long‑rod penetrators, a trend that continued with Relikt and Malachite.

When a long‑rod projectile strikes an anti‑kinetic ERA block, it first pierces the thin outer metal plate, triggering the sensitive explosive layer inside. The subsequent detonation accelerates the inner metal plates - often called flyer plates - outward at extreme velocity, directing them into the side of the incoming rod at a sharp angle. This sudden impact delivers a powerful lateral impulse across the entire length of the penetrator. Since an APFSDS dart is essentially a very long, slender rod traveling at immense speed, this transverse shock is highly effective at bending, cracking, or even completely severing the projectile. As a result, the rod either loses a substantial portion of its kinetic energy, shatters into smaller fragments that lack sufficient sectional density, or gets deflected from its original trajectory, causing it to strike the main composite armor at a less favourable oblique angle. In the best case for the defender, the damaged and destabilized penetrator simply fails to get through the underlying armour at all; in other cases, even if it does manage to punch through, its residual energy and post‑penetration effect are so drastically reduced that the crew and internal components remain largely unharmed.

Naturally, NATO powers did not remain idle. The American response was the M829A3, a round whose sole design imperative was to negate the specific threat of Kontakt‑5. Its construction features a distinctive nose cap and a segmented rod design. In practice, the forward section of the penetrator acts as a sacrificial probe - it is designed to strike the ERA tiles, trigger the explosive reaction, and be “eaten” or broken by the violently moving flyer plates. By the time the reactive armour has exhausted its energy on this forward segment, the main, much longer body of the depleted uranium rod continues its trajectory largely unimpeded, retaining the vast majority of its mass and velocity to tackle the composite armour beneath. While the Germans made significant strides with their DM43 and DM53 rounds, these penetrators were built with a different optimization in mind. The earlier DM43 proved largely ineffective against Kontakt‑5, with only about 40% probability of defeating such targets, which spurred the development of the DM53. The latter features a long nose tip specifically designed to fool the ERA fuze into sensing a much smaller projectile, about 20‑25 mm in diameter, often preventing the reactive tiles from detonating at all. Moreover, the DM53 has an increased structural rigidity and reduced risk of rod fracture upon impact with ERA plates. While this combination of a specialised tip and enhanced robustness offers a clear improvement over the DM43, it still lacks the sacrificial multi‑part nose of the M829A3, making it generally less reliable at defeating the shear effect of Kontakt‑5 compared to the American counterpart.

With the release of the upcoming update, it is crucial for players to look past the stat card and understand the specific capabilities and limitations of the M829A3. While it should be an excellent counter to any vehicle relying on Kontakt‑5 - such as the T‑90A or the early T‑72B models - it is not a universal panacea. Against the Russian top‑tier tanks like the T‑90M, T‑80BVM, and T‑72B3, which utilize the more modern Relikt ERA, the M829A3 will find itself largely stymied. Relikt is effectively a dual‑stage system designed to defeat those very same pre‑cursor rods that the M829A3 uses to trick Kontakt‑5. Consequently, against Relikt, the M829A3 performs almost identically to the DM53 - it will struggle to achieve a clean, reliable penetration and will often be defeated outright. The next generation of penetrators, such as the M829A4 and possibly the later German DM63/73/83 developments, were designed to counter Relikt, however, even those advanced rounds do not guarantee a 100% success rate.

In practical terms for your gameplay, do not expect the M829A3 to slice through modern Soviet armour with impunity. It is a highly effective against older heavy ERA, but against Relikt you are still facing a shield that requires careful aim and, often, a well‑placed second shot.

Sources:

https://www.academia.edu/145585481/Reactive\_Armor\_on\_Modern\_Main\_Battle\_Tanks\_Working\_Mechanisms\_and\_Lessons\_from\_Russias\_Kontakt\_and\_Relikt\_Reactive\_Armor

https://www.armyrecognition.com/focus-analysis-conflicts/army/analysis-defense-and-security-industry/focus-reactive-armor-a-quiet-revolution-in-russian-tank-protection

https://de.wikipedia.org/wiki/Relikt\_(Reaktivpanzerung)

https://euro-sd.com/2019/05/articles/13297/active-and-reactive-vehicle-protection-systems/

https://btvt.info/4ourarticles/armor\_72\_80\_84/armor\_72\_80\_84.htm

And overall, about the effectiveness of reactive armor against kinetic penetrators.

https://www.academia.edu/94054300/Armour\_Protection\_and\_Affordable\_Protection\_for\_Futuristic\_Combat\_Vehicles?email\_work\_card=title

https://www.academia.edu/106483107/Non\_Energetic\_Reactive\_Armor\_NERA\_and\_Semi\_Energetic\_Reactive\_Armor\_SERA\_FY13\_Final\_Report?auto=download&email\_work\_card=download-paper (Regarding the effectiveness of NERA/SERA against kinetic penetrators.)

https://www.academia.edu/75032150/The\_Influence\_of\_the\_Front\_Layer\_of\_a\_Reactive\_Armor\_on\_Long\_Rod\_Penetrator\_Disruption?email\_work\_card=view-paper

https://reddit.com/link/1thwol9/video/o26rrol3652h1/player

BTW, on the Su-57D's vertical tail you can see an interesting drawing — the two-seat Su-57D itself, the S-70 Okhotnik, the Su-75 Checkmate, and two unknown munitions.

One of them looks like a glide bomb, and the second looks like an aeroballistic (or anti-radar?) missile.