The 20th century tank is obsolete on the battlefield

This blog post is a little different from my usual content, I know, but it relates to technology, and specifically, military technology. As we have seen in the Russo-Ukrainian war, the 20th century tank is increasingly obsolete on the battlefield. In the past, the biggest threats to tanks were artillery, mines, and other tanks. This has not changed much, but the modern battlefield introduces two new threats: man-portable anti-tank guided missiles like the NLAW and the Javelin; and drones of various types, be it kamikaze, long-rate high-altitude drones like the Bayraktar, or quadcopters with grenades.

As a result, tanks have become hopelessly vulnerable, facing threats from the air, the ground, infantry and long-rate artillery. But believe it or not, this situation is not without historical precedent. When the Leopard 1 and AMX-30 were developed, the threat landscape was similarly dire; instead of heavier armour, designers focused on lighter vehicles that were more mobile, and which could gain an advantage in firepower. This advantage didn’t necessarily come in the form of high-calibre guns (the 105mm L7 gun was more than sufficient) but in the form of night vision, stabilisation, and ballistic computers.

If you are expecting this piece to argue that tanks should ditch armour and focus on being light—or that MBTs should be swapped for armoured recoinaissance vehicles like the AMX—then you’d be wrong. Tanks need to be redesigned for the 21st century, and while, yes, they should be lighter (perhaps in the 45 tonne range rather than 70 tonnes) the real solution to the problem is much more sophisticated.

Active Protection Systems

APS systems like the Rafael Trophy have proven very successful, and armies have recognised this potential, with Germany and the US retroffitting their tanks with these systems. APS systems are effective against the biggest killer of tanks in Ukraine: man-portable ATGMs. However, they are not enough on their own, and particularly, they still leave the tank vulnerable to top-attacks, i.e. drones.

How to counter drones?

When we say drones, we are referring to a large variety of systems. It is not realistic, for example, to expect a tank to defend against Reaper or Predator drones, as these will fire long-range missiles from high altitudes (that is the job of air-defence systems like IRIS-T or Patriot). However, we do need to protect tanks from ordinary sons-of-bitches like quadcopters, which might only cost $80,000 rather than millions. These systems fly lower, and have to be directly above their target to drop their payload.

Perhaps the simplest solution is tactical: have a SPAAG like the Gepard accompany each tank squad. The flak gun defends the tanks and APCs from aerial attack, while the other armoured vehicles focus on ground threats. In my opinion, this is the best solution in the short-term.

Another solution is to outfit a tank with its own air-defence system and radar. This had advantages and disadvantages. The advantage is that it makes the tank more independent, rather than relying on a SPAAG which could be shot by other tanks, or the drone itself. The disadvantage is primarily the increased cost and complexity of accommodating such a system. Also, the radar would give the tank’s position away.

The air defence system could be in the form of missiles like Starstreaker or Mistral, or it could be as simple as repurposing the tank’s machine gun. (Some tanks have two machine guns.) A machine gun firing high-velocity 5.56 or 7.62 ammunition (in the 1000 m/s range) would be capable of taking down drones at altitudes up to 500m or so. While a missile is more capable, it costs far more; it doesn’t make sense to expend a $150,000 missile to take out a drone costing as little as $40,000. Or, it might do, if it protects a multi-million dollar tank.

Stealth

The Challenger 2 is one of the few tanks to have been designed with a low radar signature. It’s a step in the right direction, but it’s not enough. Tanks should be designed with stealth in mind, as it will help them evade drones and artillery. Camouflage is one obvious way to do this; tanks hidden in forests can be very hard to spot. But the biggest problem is probably the IR signature (and noise) of the diesel engine.

I think electric tanks are a non-starter because the infrastructure doesn’t exist to support them, and range will be a problem. However, hybrid diesel-electric tanks could work very well indeed. They can use the diesel engine when on the move over long distances, and rely on electric power for stealth and urban combat.

Armour considerations

I think a tank, at least in its base configuration, should not expect survive anything bigger than a 30mm auto-cannon. From the front, it may be possible to armour it against 105mm and maybe 120mm calibre ammunition, because of the slope; but it any case not from the sides and rear.

Instead, tanks should think more about their top armour. In Ukraine, we have seen a PzH 2000 (an armoured howitzer) survive a top-attack from a kamikaze drone with a payload in the 4kg range. The howitzer was damaged, but the damage was repairable and all the crew survived. This is very impressive, and it was made possible thanks to “hedgehog” armour: rubber spikes on the top. This should become a standard applique on MBTs.

Another design consideration is that ammunition should be stored separately from the turret, as ammunition cooking off makes a hit from an ATGM or similar munition more deadly. Better to lose one man than the whole crew.