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M1A2 Abrams SEPv4: The ‘New’ Tank Russia Won’t Be Able to Defeat?

M1 Abrams. Image Credit: Creative Commons.
The Abrams Main Battle Tank closes with and destroys the enemy using mobility, firepower, and shock effect.

The US Army has relied on the M1A2 Abrams main battle tank for forty years. Yet, a new version of the vaunted tank is under development, meaning the Abrams is likely to remain in service for decades to come. The new version, known as the SEP version 4, or SEPv4, will include multiple modernizing upgrades, which should help the tank remain a valuable battlefield contributor.

“The Abrams tank sends a message to those who would oppose the United States as to the resolve, capability, and might of the US Army,” the US Army Acquisition Support Center’s (ASC) website reads. Jingoism aside, the M1A2 Abrams is indeed an advanced weapons system, worthy of an adversary’s respect. First introduced in 1980, the Abrams was well ahead of the curve, becoming one of the first “third-generation” tanks in any military, anywhere. Third-generation tanks are recognized for their composite armor and their computer-stabilized fire control systems – which represented a significant upgrade over second-generation platforms. To emphasize how ahead of the curve the Abrams was in the 1980s, consider that nations like Ukraine and Bangladesh were still producing second-generation tanks as late as the 2010s, meaning that the Abrams was more advanced in the early 1980s than the tanks that Ukraine uses today.

When the Abrams debuted, it was loaded with cutting-edge, and still-useful, features. The most significant new feature was perhaps the top secret armor; the Abrams relied on Chobham composite armor, making the tank one of the few in the world confirmed to use the advanced defense system. Chobham armor’s design details remain top secret even today, several decades after first being designed. What we do know about Chobham armor is that the design features ceramic tiles encased within a metal framework, which is then set against a backing plate that has several layers of elastic. The ceramic backplates are extremely, extremely hard; hard enough that they may prevent shaped charges from penetrating the Abram’s armor. In addition to being hard, the ceramic plates are also brittle. Why? So that when a projectile does penetrate the backplate, the Chobham’s brittleness will create a jagged entrance channel (instead of the smooth entrance that conventional metal armors leave).

The result: a jagged entrance channel creates uneven pressure points on the penetrating charge, which can cause the charge to fail. Chobham is not just theoretically superior – it has been proven on the battlefield, where Chobham equipped tanks are rarely destroyed.

Still, the US Army is working to upgrade the Abrams. In fact, the SEPv3, which the SEPv4 will be replacing, is itself rather new. The SEPv3 is “the current production version of the Abrams” and was “scheduled for First United Equipped in FY2020,” according to Army ASC. So, the SEPv3 is brand new, not unveiled until fiscal year 2020, when it was without question a highly advanced tank system. And the SEPv3 was a considerable upgrade over the SEPv2.

The upgrades were the result of difficult lessons gained from years of combat in the Middle East; the SEPv3 “rectifies many of the space, weight, and power issues identified during Operation Iraqi Freedom,” Army ASC wrote. “It is the most reliable Abrams tank ever produced.” Now, the most reliable Abrams tank ever produced is being replaced.

The SEPv4 was supposed to begin testing in 2021 – but the Army has kept the program details close to the chest. A sense of what the SEPv4 will look like is starting to emerge, however. According to, the SEPv4 will include “new laser rangefinder technology, color camera, integrated on-board networks, new slip-rings, advanced meteorological sensors, ammunition data links, laser warning receivers and a far more lethal, multi-purpose 120mm tank round.” Army ASC did confirm that the SEPv4 would feature 3GEN FLIR technology, which will assist in conducting nighttime operations. The new FLIR technology will help Abrams crews target enemies, while also avoiding friendly fire incidents.

So, the Abrams should be both the most lethal – and the safest – US tank yet.

Harrison Kass is the Senior Defense Editor at 19FortyFive. An attorney, pilot, guitarist, and minor pro hockey player, he joined the US Air Force as a Pilot Trainee but was medically discharged. Harrison holds a BA from Lake Forest College, a JD from the University of Oregon, and an MA from New York University. He lives in Oregon and listens to Dokken. Follow him on Twitter @harrison_kass.

Written By

Harrison Kass is a Senior Defense Editor at 19FortyFive. An attorney, pilot, guitarist, and minor pro hockey player, he joined the US Air Force as a Pilot Trainee but was medically discharged. Harrison has degrees from Lake Forest College, the University of Oregon School of Law, and New York University’s Graduate School of Arts & Sciences. He lives in Oregon and regularly listens to Dokken.