Fall of the Landship
When the first tanks lumbered onto the Somme in September of 1916, they ushered in a new era of combat. But while those tanks were cutting-edge technology, the theory behind them was much more primitive. In terms of application, the British Mark I tank, with its distinctive rhomboidal design, was much closer to a medieval siege engine than a modern Main Battle Tank (MBT). It was there to break the enemy defensive lines and little more.
By the end of the war, tank theory was already evolving. The first tank-vs-tank engagement happened on April 24, 1918, and the diminutive Renault FT-17 set the basic design that would hold into the modern era. In 1918 a British officer by the name of JFC Fuller had devised a 5,000 tank attack supported by aircraft and artillery. Dubbed Plan 1919, JFC Fuller’s proposal to end the war had many modern elements. It is unlikely JFC Fuller’s plan would have been enacted had the war dragged on, but it demonstrates how theories regarding the use of tanks were evolving.
At the war’s end, JFC Fuller was not the only one trying to determine what the future of the tank may be. Throughout the interwar period, the major powers wrestled with the concept of the tank. Its value was not lost but tacticians were not sure how to best employ the new weapon. It became a period of great experimentation in theory and design. Some armies attempted to simply slot tanks into preexisting cavalry and infantry roles.
Here heavy “breakthrough” tanks broke the lines with the infantry while lighter cavalry tanks exploited those breaks. Others began looking into modern combined arms formations. More extreme theorists looked to the Navy for inspiration. They envisioned a possible future where wars were won by fleets of “landships” maneuvering on the field with everything else taking a subsidiary role. As is often the case when putting early theories into practice, designers borrowed from both the landship and breakthrough ideas to produce a historical oddity: The multi-turreted tank.
All multi-turreted tanks shared a basic design layout where the main turret was supported by up to four sub-turrets. The main turret held a cannon while the sub-turrets held machine guns or smaller cannons. The idea was that their 360-degree firepower would allow them to blast through enemy defensive lines while still being able to engage enemy tanks. A few models, such as the Soviet T-35, had a pair of cannons that could theoretically engage separate enemy vehicles at the same time. It was not long before the design became obsolete though. By looking at how multi-turreted tanks failed, one can also understand why the modern MBT design succeeds.
Complexity
The complexity of these tanks was their first downfall. Compared to other tanks of the day, multi-turreted tanks were massive and complex. The space required to fit four to five turrets dictated a large hull. To move a large hull weighted down by the turrets required a large engine. All of this weight puts a greater strain on the vehicle. The drivetrain, tracks, and suspension were particularly vulnerable to the loads. Furthermore, because they were limited in width by the railways transporting them, the designers added length to support the turrets and engine. The long hulls increased the wear on tracks when turning.
The excess turrets created further maintenance problems. Speaking from experience as a former Armor Officer, tanks are difficult to maintain. Every addition is a potential point of failure. Five turrets equal five times the opportunities for problems to arise. It also requires Supply to have five times the amount of parts and the crew to take care of more equipment.
But the biggest negative here was the sheer cost. An early multiturreted tank, the A1E1, cost 150,000 Pounds Sterling to develop and build one copy. This was an exorbitant sum for a tank. For reference, the excellent Vickers 6-Ton tank from the same era could be purchased for 4,200 Pounds Sterling. The size also meant it was costlier to transport, fuel, and maintain the vehicle. And for all that expense, the vehicle had very little use outside of a major conflict.
The complexity of design compromised protection too. Though designers had not fully grasped the best practices for armor plating at the time, generally a cohesive armor scheme provided the best protection. The irregular surfaces created various weak points and shot traps in the armor. The Soviet SMK came closest to solving this problem but it still had serious weak points in the armor when compared to simpler heavy tanks of the era.
Finally, the height of these vehicles was a problem. Tank designers strive for a low silhouette. A low profile makes the tank harder to see and hit. But on multiturreted tanks, the main turret had to be able to fire over the sub-turrets. This required the turret to be mounted on an elevated platform. The platform dramatically increased the tanks' profile and created an irresistible target for enemy gunners.
Command and Control
For a Tank Commander (TC), appropriate control of the vehicle is their primary task. In no place is this more obvious than the utilization of the vehicle's weapon system. In modern doctrine a tank engagement is supposed to go something like this:
Gunner: Identified tank! [This informs the TC he has a target and type]
TC: Gunner, sabot, Tank. [The TC command confirming who is doing the shooting and what round they are shooting; TC should also confirm what the gunner is looking at]
Gunner: Sabot indexed, range 1800 meters. [Gunner has confirmed ammunition type dictated by the TC. The range call is the signal the gunner is ready to fire]
Loader: Up! [A confirmation that the correct round is in the tube and the cannon is off safe]
TC: Fire and adjust! [Permission to fire and make necessary follow-on shots]
Gunner: On the way! [A warning to the crew, the trigger is pulled on the Y of way]
TC: Target, ceasefire. [You have hit and destroyed the target, stop firing, safe the weapon]
Despite the length of this sequence, a good crew executes it in seconds. And in combat situations with a familiar crew, it gets reduced even further. But the important thing to note here is the amount of control the TC exerts. The TC is ultimately responsible for everything the tank engages. During engagements, he/she has to ensure the target they are aiming at is an enemy vehicle. However, they also have to keep track of where friendly vehicles and units are, confirm the priority of the target (ie not engaging a truck while an enemy tank is looking at you), verify the appropriate ammunition is being used, and ensure their driver is not heading straight into a ditch. This is just for wingmen tanks. For platoon and company-level leaders, the level of multitasking gets exponentially higher.
From this perspective, a multi-turreted tank is a TC’s nightmare. It is not humanely possible to simultaneously control five weapon systems. In WWI this did not matter much; the battle lines were set and the crew just blasted away knowing that anyone ahead of them was the enemy. But by WWII tanks were fulfilling more dynamic roles, roles in which the TC would have needed more control over the tank. Such considerations rendered these tanks obsolete before they even left the drawing board, but they still lingered on.
The Closing of an Idea
In WWII multi-turreted tanks were already an antiquated concept, but the existing ones soldiered on until they were knocked out or pulled from service. The final nail in their coffin was the need for larger guns. As tanks got progressively better armored in WWII, gun size and power increased dramatically. These guns increased the size of turrets to the point where multiple turrets were not feasible.
For all their complexity and difficulty to control, the one advantage multi-turreted tanks had was 360-degree protection. But once the coaxial machine gun was perfected this advantage went away. The coaxial machinegun also provided 360-degree protection while being light, simple, and easy to control. Finally, tanks rarely operate alone. By mid-WWII radios were common enough that wingmen could cross-talk with one another to deal with threats.
Perhaps the multi-turreted tanks' most important role was in iconography. Dwarfing contemporary vehicles and bristling with guns, these tanks were far more effective at projecting power than utilizing it. It comes as no surprise that Soviet multi-turreted tanks featured heavily in their propaganda and Mayday parades. The vehicles conveyed aggression and power, so much so that their design influences can still be seen in the vehicles of dystopian fiction such as the Warhammer 40K universe.
But the multi-turreted tank concept may be quietly returning. Advances in robotics and remote control technology have led to a resurgence of independent machine guns. Modern M1 Abrams are currently being retrofitted with the CROWS system. This system is effectively a remote-controlled sub-turret mounted to the top of an Abrams and is controlled by the TC. It provides TCs with a safer and more accurate way of engaging targets than the old, external .50 caliber machine guns. Ironically though, CROWS shares many of the same flaws as the multi-turreted tanks of old: it is heavy, tall, and complicated.
