CHAPTER 6 – WHAT NEXT FOR THE MAIN BATTLE TANK?
Now that we have reviewed the history and recent combat experience of main battle tanks, it is time to analyze those factors and decide what the future could have in store for modern MBTs.
THE LESSONS TO BE TAKEN INTO CONSIDERATION
As stated before, MBTs are presently judged mainly by three major qualities: firepower, mobility and protection. In terms of firepower, the present generation of MBTs are more than adequate in most cases, with powerful, high-velocity guns able to take out enemy tanks, vehicles, bunkers and other hard targets. However, that gun firepower comes at a price. Those tank guns in the 120-125mm caliber range weigh a couple of tons or more, not counting their support cradles and elevation mechanisms. With the present calibers in use, any future augmentation in caliber would result in rounds too heavy to be handled for any length of time by a human loader, while the total length of those bigger rounds would necessitate to split them into two loads: the projectile plus its propellant charge. Such split rounds would further slow down the rate of fire and would complicate the gun loading process, all this in the constricted internal space of the tank turret. High-velocity tank guns also have a hefty recoil and a length overall of about six meters or more, something that has to be taken into account when designing a new tank turret, so that the elevation limits of the gun inside the turret would not impact on the tactical effectiveness of the gun. This has already been a marked problem in Soviet-designed tanks, whose limited gun depression angles complicate their aim when engaging targets situated below their own tank location. The rather crude solution adopted by the Soviets for that problem was to carry a large log on their rear deck, so that the crew could put it down on the ground, just behind the tracks, and then roll in reverse over it in order to make the whole tank take a nose-down attitude. The reverse is also true, with the maximum elevation of tank guns being too limited to aim at any target past 15-20 degrees above them, like enemy tanks posted on a dominant ridgeline or snipers located on the upper balconies or roofs of surrounding buildings. Such elevation limits also impede the engagement at short ranges of enemy helicopters flying higher than treetop level. The solution to this would of course be to design the tank so that its gun would possess larger angles of elevation and depression but that would greatly complicate the design of the turret and would also make the tank silhouette much higher, a definite negative point in tactical combat. Another limitation of existing modern tank guns is the limited variety of rounds they can carry and fire. Most tanks with 120-125mm guns normally carry only two kinds of gun rounds: an anti-tank long-rod penetrator round (armor-piercing, fin-stabilized, discarding sabot, or APFSDS in short) and a multi-purpose round able to take out vehicles with modest armor protection, bunkers and personnel in the open. The main exceptions to this are the British tanks, which use rifled 120mm guns able to fire multiple types of ammunition. However, those extra types of rounds severely impact on the limited overall number of rounds carried inside the tank, by lowering the number of anti-tank rounds considered as the main type of ammunition for a tank. In the case of Soviet tanks, like the T-72, T-80 and T-90, their carrousels can carry and load a few anti-tank guided missiles, on top of the normal high-velocity anti-tank rounds and multi-purpose rounds. Those gun-fired missiles also have some anti-helicopter capacity, a not negligible capability on the modern battlefield.
Added to the main gun armament of modern MBTs is a varied assortment of machine guns or grenade launchers, either coaxial to the main gun or on a top-mounted pintle mount or small top turret. Those secondary weapons are meant to deal with enemy infantry and soft targets, like trucks and other logistic support vehicles. This helps the tank to conserve its precious main gun ammunition for harder, more significant targets. The French AMX-30 demarked itself in that aspect by having a 20mm cannon rather than a medium machine gun as its coaxial weapon. All modern tanks also carry, attached around their turrets, a number of low-velocity, one-shot grenade dischargers, which can provide a nearly instant protective smoke screen around the tank as it retreats from enemy fire or changes tactical position. The Israeli MERKAVA is also special in that aspect, as it carries as well a small 60mm mortar as part of its secondary armament. However, the more diverse the armament on a tank, the more complicated the ammunition resupply problem becomes. The more advanced types of MBTs may also carry an active defense system which detects incoming projectiles and then fires special types of munitions to intercept and destroy those projectiles before they could hit the tank. However, the efficacy of such active defense systems still needs to be fully proven in combat.
Now, about mobility. Mobility may be the domain where most critiques could be made against modern MBTs. While their tactical mobility ranges from good to very good, with theoretical top speeds of up to ninety kilometers per hour on roads, their operational mobility is a lot more limited, while their strategic mobility positively sucks! The problem here is the sheer bulk and mass of modern MBTs, with widths of 3.5 meters or more and weights going from 45 tons all the way to 75 tons. This means that the width of all modern MBTs surpasses the standard rail gauges used in most countries (3.15m Berne International, 3.5m Western Europe with restrictions, 3.32m Soviet wide gauge), which in turn complicates any movement of tank units by rail, forcing railroad managers to temporarily restrict travel along parallel rail tracks. Also, only a portion of existing bridges and highway overpasses can support the mass of MBTs, which means that the movements of tank units along existing roads and bridges have to be carefully planned, further limiting the operational mobility of tank units. When it comes to movement by air, the problem becomes even more acute, with only a handful of heavy transport aircraft types being able to lift and carry a single MBT, at great cost in fuel. Sea movement via ro-ro type cargo ships is a lot more practical but such ships take a week or two to cross the oceans and deliver their loads to the operational theater. Once at destination, powerful low-bed semi-trailer trucks are then needed to carry the MBTs closer to the battlefields, in order to save from unnecessary wear the tracks and automotive components of the tanks. Finally, even at tactical level, tanks hate soft grounds, like mud, bogs and deep snow, with many of them ending up sinking into soft grounds and getting stuck. They also mangle the terrain behind their tracks to the point of making it impractical for wheeled vehicles to follow them. Just ask a European farmer what he thinks about tanks after a column of MBTs has just plowed through his fields during a military exercise and you will get some salty response from him. The only realistic solution to the mobility problem would be to significantly cut both the bulk and the mass of main battle tanks, something that cannot be done without affecting the protection level of the tank. A difficult tradeoff would thus be needed deal with that problem.
PROTECTION LEVELS: DESIRABLE VS REALISTIC
Next is the matter of protection level in a tank. Armor protection was the primary reason the tank was invented and used since WW1, in order to making it safer to cross the battlefield while under enemy fire. During WW2, the matter of armor protection levels was a bitter subject of discussion among Allied tankers riding American or British medium tanks, like the SHERMAN and the CROMWELL, while having to face such scary monsters as the PANTHER and TIGER. The demand then was for ever more armor, which meant in turn heavier tanks and the need for bigger and more powerful engines in order to keep some acceptable level of mobility. This competition between firepower and protection continued after 1945, resulting in progressively bigger and heavier new tank designs, with the poor mobility factor stuck between those two other factors. Then came the advent of anti-tank guided missiles and rockets equipped with large caliber shaped charge warheads (HEAT) able to pierce about any existing tank at long range. That fueled another scramble for improved protection, resulting in the development of new types of armor able to better resist HEAT warheads, like spaced armor, multi-layered composite armor and explosive reactive armor (ERA). However, reactions inevitably trigger counter-reactions and the tandem HEAT warhead was then invented, in which a small precursory charge carried at the end of a nose probe of the missile, ahead of the main HEAT charge, causes the ERA bricks protecting a tank to detonate prematurely. Then, the main HEAT charge explodes and burns through the main armor. Now, many types of modern anti-tank missiles and rockets have such tandem HEAT warheads, thus rendering the utility of ERA questionable. Just look at pictures of Russian tanks destroyed by man-portable anti-tank weapons fired by Ukrainian infantrymen and you will see that nearly all of them are covered with ERA bricks. Yet, those Russian tanks had their turrets blown off after those missiles and rockets burned through their hulls and ignited their reserves of gun ammunition. So, what can be done to realistically limit the effectiveness and lethality of those modern portable anti-tank weapons? The honest answer is: not much. Claiming that more armor would solve that problem would be a fool’s errand. As for the active protection systems touted for the newest generation of MBTs, I will say this: I will believe in them once they will have proved their efficiency on the battlefield. Too many variables are in play for us to rely only on theoretical studies and pre-arranged field trials. The best protection is still for the tank to not get hit in the first place, which in turn places a special premium on mobility, agility and small vehicle silhouette. A more fundamental question would be: how much protection is realistic vs desirable? The actual course to continuously add more armor to tanks and to bet on complicated and expensive active protection systems, with their own electronic sensors vulnerable to all the projectiles flying around the battlefield, while new anti-tank weapons continue to emerge, simply cannot go on for much longer.
THE MAIN BATTLE TANK: STILL AFFORDABLE?
Another criticism made about main battle tanks is their high unit cost, which is now in the multi-million dollar per tank and tends to blow the minds of national budget managers around the World, while the best man-portable anti-tank guided missiles can be had for a few thousands of dollars apiece. Here is a short list of the more modern types of MBTs in existence, with their approximate official unit cost, combat weight and width (the two latter factors directly affecting operational and strategic mobility):
As you can see from that list, buying a fleet of modern MBTs, on top of paying for its maintenance and operation, is not something every country can afford. In the case of the new Russian T-14 ARMATA, first seen in a Moscow parade in 2015, it is still not in service in any sizeable quantity. One of the reasons proposed for that lack of T-14s in active service, apart from rumors of teething technological problems, is its high price, which the Russian government may not be able to afford in quantity. The recent economic sanctions and embargos on electronic parts inflicted on Russia after it started invading Ukraine will certainly not help in accelerating the putting into service of the T-14. So, for the moment, we may have to consider the Russian T-14 tank as merely a show piece.
WHAT WEAPONS?
Since the main goal of main battle tanks is to engage the enemy and destroy it, the question of its armament is certainly a primordial one when designing a new tank. To better decide what armament to put on a new tank, we have to consider what it will face in the field and in what conditions. Is the battlefield area constricted (built-up areas, forested areas, jungles, hilly country) or wide open (desertic areas, arctic tundra), or a mix of open and constricted areas? In that aspect, a country like Saudi Arabia will certainly not need the same kind of MBT than what Sweden or the Netherlands would need. Does the potential enemy have a modern anti-tank arsenal and modern tanks, attack helicopters, attack aircraft and armed drones? In the case of the war in Ukraine, the Ukrainian forces have proved to have all of these, so its opponent would have had to plan for the worst scenario in terms of Ukrainian resistance. While the invading Russian forces certainly had the types and quantities of weapons and equipment required to successfully invade Ukraine, their failings were more in how they used (or misused) their weapons, including their tanks, something that relates to the human factor. The Russians also failed to take into account all the modern portable anti-tank and anti-aircraft missiles which were being sent by the thousands to the Ukrainian forces by NATO countries and thus got badly burned right from the start. The fighting to date in Ukraine also pointed out some major problems with Russian equipment and armored vehicles. Russian tanks, while in theory well protected and extensively using ERA armor bricks, still blew up with disconcerting regularity when faced with portable anti-tank weapons like the JAVELIN, NLAW and PANZERFAUST 3. The Russian tanks could probably have used weapons better adapted to fight off the enemy infantry, like tank gun canister shells or remotely-operated machine gun mini-turrets. However, the best weapon for tanks against enemy infantry is still friendly infantry in close support. The Russian tanks, like other Russian vehicles, also proved vulnerable to the armed drones used by the Ukrainians, something that integral anti-aircraft missiles on Russian tanks could have helped them in fending off those drones. One notable point about tank guns is that their so-called multi-purpose shells, being of the HEAT-Fragmentation variety, are less lethal than artillery shells of the same caliber, producing less fragments and a smaller lethal radius. While most tanks have turret roof-mounted machine guns on pintle mounts, a crewman sticking his torso out in order to man it would quickly become a target for enemy riflemen and snipers hiding around the tank. A remotely-controlled turret would thus definitely be a better solution in that case. However, that raises the question of who would operate that mini-turret? In tanks crewed by three men, like the T-72 or the LECLERC, that would add an extra task to a crew already barely large enough to fill all the basic combat functions of a tank. Even with a loader present as a fourth crewmember, having to man a machine gun turret would severely affect the rate of fire of the main gun. The point here is that close protection of tanks from enemy infantry is a very real and serious problem, one that has to be addressed. Contrary to the German soldiers of WW1, well-trained modern infantrymen can now fight on nearly equal terms with main battle tanks, if equipped with effective weapons and using good tactics. If the tanks are not able to obtain some friendly infantry as close escort, then they will have to assume that task by themselves, something that present modern MBTs are ill-designed to do, unless some imaginative tank commander decides to stick directional anti-personnel mines like the CLAYMORE all around the chassis of his tank and detonates them as he goes. Another solution would be to have extra smoke grenade dischargers fitted and loaded with HE-Frag grenades, which could then project a number of explosive grenades all around the tank, in order to pepper the enemy infantry with shrapnel. To recap, a main high-velocity tank gun and one or two machine guns may look sufficient at present to do the job for a MBT, but actual combat experience is showing that notion to be flawed.
WHAT KIND OF FUTURE: STAGNATION, EVOLUTION OR FADING AWAY?
If one goes by the various tank projects being presently pushed around the World, it seems that the trend towards ever bigger, heavier and more protected tanks will continue for at least a few years. No actual tank project is truly trying to break out of that mold, mostly due to ingrained conservatism among the senior military staffs, who are the ones establishing the desired specifications for new combat vehicles. Add to that the political interference by officials with no true understanding of what is needed in military terms and who are mainly preoccupied with obtaining juicy contracts for the defense industries established in their constituencies and the end product will often not reflect what is truly needed. Right now, the chances of seeing a truly revolutionary main battle tank design emerge somewhere and be adopted by a government are about zero for the next five to ten years. However, there are a few examples of hybrid types of combat vehicles, like the Russian BMPT TERMINATOR, that have appeared and are of interest. The BMPT TERMINATOR is classified as a ‘tank support fighting vehicle’ and was designed for supporting tanks and other armored fighting vehicles inside urban areas. It is armed with four anti-tank missile launchers, two 30mm automatic cannons, two 30mm automatic grenade launchers and one coaxial medium machine gun. It is built on the chassis of the T-72 tank, is well protected and weighs 48 tons. It was first introduced into limited service in 2018, while a variant based on the chassis of the T-14 ARMATA tank and named ‘BMPT TERMINATOR 3’ appeared in 2021. However, the BMPT is still not in widespread service and none of them have been seen in Ukraine, where they would undoubtedly have proved themselves useful if properly employed.
Finally, here is some dreaming of my own. What I imagine as a successor to the actual MBTs is a smaller, lighter, more mobile armored combat vehicle armed with a combination of missile launchers for long-range anti-tank and anti-helicopter/anti-aircraft combat, one 30mm automatic cannon to deal with enemy armored troop carriers and one large caliber, low velocity gun of a caliber of at least 150mm meant to fire highly destructive explosive rounds against bunkers and soft targets and to also ideally be able to fire as well guided missiles through the tube, with both the 30mm cannon and the large gun mounted together in a high elevation, compact turret. An automatic loader would be used to feed a mix of heavy rounds/missiles to the large gun, while two extra crewmembers, located in the rear, would man two mini-turrets armed with medium machine guns or automatic grenade launchers, with the task of protecting the vehicle on its sides and rear against infantry ambushes. A number of directional fragmentation mines could be fixed in armored boxes around the hull, to deal with approaching enemy infantry, and would be remotely-detonated by the vehicle commander. If enough space could be found inside the vehicle, a fire team of four infantrymen could ideally be carried, ready to dismount when needed. The vehicle could use a modern, compact but also powerful diesel engine like the MTU 890 Series, which would be located in the front of the vehicle, with the transmission, possibly of the electric drive type. This would both keep the bulk and mass of the vehicle to a minimum, while allowing the use of the rear half of the vehicle for the combat systems and crew. It would also allow the base vehicle to be used to produce multiple variants for different roles. Since the actual armor vs weapon appears to be an endless and futile competition, the base armor would be designed to only resist automatic cannon shells and low velocity medium guns, in order to keep the vehicle’s mass below forty tons, and ideally below thirty tons, so that the vehicle would be easier to transport by air and could roll on roads and bridges without mass constraints. I strongly believe that such a vehicle could be designed, as long as the designers and project managers show open minds and accept to leave the beaten tracks. I strongly believe that the actual MBTs could be better replaced by a combined arms armored combat vehicle (CAACV) as described above, able to deal by itself with the various threats found around the modern battlefield. Adopting such a type of vehicle would of course mean a rethinking of army combat doctrines and unit organizations, but I believe that a full integration of all combat arms in a single, homogeneous unit is a necessity rather than a dream. If that course is not eventually taken, then armies will continue to lose multi-million-dollar main battle tanks (and their crews) to foot soldiers armed with portable anti-tank weapons costing only a few thousand dollars each.