M1A2 Abrams SEP v3: Upgrade Time

Well, the Russians have a new tank. And, for all its failings, the US Army is poking General Dynamics Land Systems for some Abrams upgrades to keep pace. Let’s see what they look like.

A brief aside: A separate program, and therefore not included in the SEP v3 upgrade package is a new anti-armor round. It’s the M829E4 round. It’s an APFSDS-T round, and it uses depleted uranium. It’s awesome, but very classified. Interestingly, I saw this a couple weeks after the T-14 was unveiled in a parade, which I find to be interesting timing. Connect two facts…

Anyway, SEP v3!
GDLS has added an under-armor auxiliary power unit (the UAAPU). It’s in the rear left quarter, replacing part of a fuel tank there. This should help with the inefficiency of the big AGT 1500 when it’s idling. Judging by the exhaust the UAAPU probably uses a very small gas turbine. It’s a good application for one, since turbines are small for their power and reasonably efficient under load. It should also help with providing all of the power needed for today’s fancy electrical systems. The UAAPU should provide enough power to run the turret (and everything in it) with the engine off. About time.

The SEP v3 also brings out the armor upgrades. The turret face and the front hull are better than they were before. How much better? Classified. Hooray for a new composite armor array though. I’m not sure if either section has gotten thicker, since I don’t have time up close with the SEP v3 and older v2 units. But the front armor is better now.

The Abrams has gotten some changes to its roof-mounted remote weapons stations. Tank crews in the field complained that the existing units tended to block their view a lot when the buttoned up. Also, they’re quite large, which makes going under bridges and things annoying. So there are new remote weapons stations that are lower profile and placed better to not obstruct the view as much. Happily, there are two RWSes as standard: one with an M2 for the tank commander and one with an M240 for the loader. I always approved of the number of machine guns on the Abrams. It takes advantage of that fourth man to operate another machine gun if he’s not slinging shells for the main gun. This is a big plus in urban areas.

The Abrams finally sees an upgrade to the M256 that lets it interface with guided rounds. There’s a new breechblock that can now perform this task. So integrating gun-launched missiles (such as the Israeli LAHAT) or airburst rounds can actually proceed. About damn time. The Israelis and the Germans have been able to do this on their 120 mm guns for years now. There are also plans to integrate a new airburst round to replace some other antipersonnel and demolition rounds that are currently in the inventory.

The thermal sights on the SEP v3 have been improved to be ‘third generation’ units. So they can see in both long-wave and mid-wave infrared. This allows for better images on the screens as well as better ability to see through obscurants like smoke or fog. Obvious capability win.

Finally, let’s talk about what’s not included: a new gun. It is not clear to me that the Abrams needs one, given the new round and the changes to the M256 to enable linking with smart rounds. They could deploy the XM360E1. They could also field a new 120mm/L55 gun, though this would require some upgrades to the stabilization system.1 If they’re going that far, they might wait to see/opt for the Rheinmetall 130 mm gun. We shall see. For the foreseeable future, I don’t think this is a huge concern.

No side armor changes have been announced. This is unsurprising to me. It is not feasible to provide protection from MBT main gun rounds on the sides. The concern you can do something about is RPG-type attacks, and the Abrams already has an excellent armor kit for the hull skirts and turret sides from the Tank Urban Survival Kit program.2 These systems are tough and combat proven. No more is needed. The TUSK program also added some optional belly armor to counter the IED threat. Again, more isn’t likely needed in the immediate future.

The SEP v3 still lacks active protection systems. Several are under evaluation, and may show up in a follow-on program. The US Army is particularly keen on Trophy, but there are also some promising systems from Raytheon.

Overall, this is a really good set of upgrade features, and there are more follow-ons coming. There are at least two engineering change proposals floating around out there. For once, this is a reasonably well managed program, introducing phased upgrades to keep an older platform competitive. Way cheaper than designing a new one, but it keeps the factories busy (and therefore open). Also, not trying to do everything at once keeps budgets under control and reduces the chance of the dreaded budget kill.

I would love to compare this to the German Leopard 2 improvements (2A8 anyone?), but nothing concrete has been announced. The US Army is doing a really good job of keeping on top of upgrades right now. These new upgrades should help make sure that the Abrams is a match for any tank out there. I’m also pretty happy about the lack of gold plating so far. Better knock on wood there.

1.) This drove the cost up too much back in the 90s when this was last considered. Back when there was no Russian threat to speak of. The US Army has been happy with their depleted uranium alloy rounds. Which tend to perform about as well as a similar-vintage tungsten-based-alloy round from the L55 gun, so maybe Big Army bet right on this.
2.) Specifically the XM-19 ARAT-1 and XM-32 ARAT-2 reactive armor packages.I’ll have a write-up as soon as I can get more information. There’s not much out there on these, especially on the newer XM-32s.

1 thought on “M1A2 Abrams SEP v3: Upgrade Time

  1. Pingback: Abrams Additions - The Soapbox

Leave a Reply