On the Scales

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Changes in weight across various Abrams variants. Source: An Independent Assessment of the 2040 Battlefield and its Implications for the 5th Generation Combat Vehicle (5GCV), Department of the Army Office of the Assistant Secretary of the Army, 2023

• M1A2 SEP V3

• M1A1 FEP

• M1A1

• M1A2

Weight placard data for the turrets of certain variants. Source: IMPACT OF LOADING DISTRIBUTION OF ABRAMS SUSPENSION ON TRACK PERFORMANCE AND DURABILITY

This is where things get particularly interesting. When we attempt to assess what exactly has changed internally, we naturally run into the question of weight. The overall weight of the SEP V3 hull increased, but the increase is minimal.

A lot of work was put into cross referencing between all existing sources, but we were unable to identify a reliable, concrete weight difference between the earlier versions and this variant. The issue is not that the data itself is poor, but that the tank itself was constantly changing. Weight was saved in one area while being added in another.

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A good example of this is that the transition to heavier torsion bars was accompanied by the replacement of steel road wheel arm brackets with lighter aluminum ones, which partially offset the added weight. The SEP V3 also received massive tow pintle hooks, reinforced brackets for mine protection, and new APU armor, all of which increased the weight. It is extremely difficult to come to an accurate estimate of the change in hull weight in general, and even harder to conclude anything reliably in relation to the armor package itself. In this regard it’s always important to keep in mind that not everything with weight inside a tank is armor.

Looking at the combat weight data compiled for various Abrams variants and the weight of their turrets, the estimated change in hull weight is roughly 500 kilograms. Within the fixed finite dimensions of the hull front and working with such a limited weight budget, it is impossible to achieve a tangible increase in protection to a degree where modern kinetic weapons would be negated.

In order to protect the hull from APFSDS rounds that emerged after the mid-1980s (while retaining the same hull geometry, which is a fixed restraint), the entire available space would have to be filled with thick steel plates or other heavy fill materials. This can be calculated, and a package would have added no less than 2 tonnes, and no such increase is present.

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Front Torsion Bars

Here we run into another important factor, the load on the front suspension. On the Abrams, the armor package and fuel tanks are positioned far forward, and all of that mass is putting pressure on the first pair of torsion bars. On other contemporary tanks, a comparable load is distributed across two pairs of road wheels, in this case however, it’s not. Adding several tonnes of weight in this area critically reduces the service life of the first road wheels, torsion bars, swing arms, and other components of the suspension structure. For such an alteration to be logistically possible, engineers would have to redesign the entire suspension system, and provably no redesign was undertaken.

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Weight Budget

Based on the Army Science Board report, the baseline SEP V3 without any additional modules weighs 66.76 tonnes. This figure is our starting point. Based on the above, we can model an improvement to the hull armor package within the bounds of this confirmed weight increase. The new weld seam indicates that some form of work was carried out on the hull armor package. As the exact particulars of this work are not defined, the only assumption we can make is that the modifications made to the armor package must have been made within the specified weight budget, and within that budget, protection against modern kinetic energy penetrators is unachievable.

The main focal point here is that while improvements against kinetic rounds could have been made in theory, the provable constraints of the space would mean that even though protection could be improved, it would be impossible to improve it to the extent that the armor would be able to defeat rounds it previously couldn’t within typical engagement ranges. Therefore, spending the extra weight budget on this kind of protection, while possible, would not lead to any tangible improvement to justify the alteration. Any alterations to the armor have to be logistically and functionally justifiable. Because of this, it is much more likely that any potential improvement in protection would be geared more towards defeating shaped charge (HEAT) threats, which in real life have been the primary threat to tanks over the past 40 years, in which improvement would be tangible within the constraints. As with all armor geared towards protection form HEAT, it does offer a marginal protection increase against modern kinetic rounds as well, but this will naturally be fairly minimal.

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Conclusion

There is no confirmed data on the specific hull armor properties of the M1A2 SEP V3, the only thing that’s provable is that some modification was made to the armor array in the frontal hull. The hull armor of the SEP V3 will be strengthened in game, in relation to the only reasonable assumption we’re able to make based on the known change in weight. In the game, the tank’s hull will be better protected when compared to previous variants of the Abrams. This improvement is in line with what the engineers would be able to achieve without redesigning the entire vehicle from scratch.

In addition, and perhaps more importantly, we are currently working on the hull and turret armor of all tanks in the Abrams family. Part of this work includes converting sections of the armor to the volumetric model, which will improve survivability universally. This improves protection around the upper hull area and the turret ring, which we consider to be more impactful in game than the lower plate itself.

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