Tank

Were you looking for the MMO character role that gets applied to tabletop games? If so, we have that under Combat roles.

"Remember Comrades, we are tank!
They take out treads, we are artillery!
They take out main gun, we are pillbox!
They take out machine gun, we are bunker!
They take out armor, we are heroes! "

– A popular internet copypasta about a tank's various roles in a nutshell

"It got in the way... and it died."

– Company of Heroes 2

A French Renault FT-17 Tank, the first tank to have the rough layout that would be the norm for tanks (Crew in the front, top mounted 360 degree turret for main gun, engine in back)

A tank is a tracked, armored combat vehicle. The term is often limited to vehicles intended for direct combat, (e.g. as opposed to self-propelled artillery, which stays to the rear) or armored personnel carriers and infantry fighting vehicles, which are on the front line but are primarily tasked with carrying soldiers as opposed to fighting directly and may not necessarily be tracked. Their invention revolutionized warfare in the 20th century, and any wargame set in or after that time period, or in alternate universes with similar or more advanced technology levels, will have plenty of attention devoted to them -- or to whatever made them obsolete or of secondary importance to militaries (e.g. BattleTech).

The idea of an armored fighting vehicle dates back at least to Leonardo da Vinci and was explored by H. G. Wells and a few theorists, but the modern tank was proposed shortly before World War I, and was then spurred to production by the war itself. When the war on the Western Front got bogged down in trenches, the British Royal Navy, who had already had some success with mobile armored car groups, had the idea to use tracked, armored vehicles with guns to break the stalemate. The name "tank" became attached to the vehicle as a codename to disguise the purpose of the large metal bodies being built. After the first tanks rolled onto the battlefield, other countries called them "battle wagons", "armors", "assault vehicles", and other more descriptive names, but the Anglosphere was stuck with calling them "tanks". (Interestingly, the original British Tank, which looked like a tractor with a metal box on top of it was called "Little Willy".)

Common Features of the Tank

Tanks were built with pretty much any set of features you could imagine, but over time, the militaries of the world settled on several common key features:

1. One single main gun, carefully chosen so it is powerful enough to knock out other tanks with armor-piercing shots and still able to use high-explosive shells to deal with 'soft' targets.
2. A turret to house the main gun, to allow the tank to shoot at targets without having to pivot the entire vehicle.
3. Good protection against most battlefield weapons, with a heavily-armored front face to defeat anti-tank weapons.
4. An engine with a lot of torque and horsepower to give it both decent acceleration and top speed. The ability to run on multiple types of fuel is a big plus.
5. Tracks with independent long-travel suspension for each roadwheel, to improve mobility.
6. A radio of some kind. If that sounds odd, realize that a tank in the middle of battle will have shit situational awareness, even many modern tanks, so having some kind of coordination and forewarning is absolutely a crucial part of tank warfare. (One of the factors that let German tanks run circles around the French in WW2, despite being otherwise inferior to French designs, was that German tanks had radios, while the French ones didn't)
7. As of the early 2020s, some kind of thermal imager. While not all militaries have them, these things are "must-haves" for a functional tank: A thermal imager allows you to fight at night, spot enemies, and have greater situational awareness, to the point of making an otherwise bad tank actually useful, and the absence of one turning an otherwise good tank into a dead tank walking.

Basically, tanks boil down to three main features: firepower, defense, and mobility. Trying to specialize in one or two attributes tended to come at the expense of second or third attributes. The heavier your guns and/or armor, the slower the tank will be, for instance, while a vehicle made for mobility has to sacrifice either protection or the size of its guns. Nowadays, tanks designers try to maximize all three attributes by being cleverer about achieving their goals, with their main limitations being weight and profile. Additionally, a fourth factor to consider in design are support systems: while not necessarily integral to the design of a tank, they are nonetheless essential in allowing it to work as one, as evidenced by the radio.

Offense

As mentioned in the summary above, one of the if not the defining attribute of the modern tank is its main gun. A modern (i.e. third gen and up) main battle tank must be able to engage any threat it encounters on the battlefield (and occasionally flying above it), hence the gun itself is a carefully weighed compromise between raw firepower, versatility, and overall mass. Nowadays most tanks sport a gun with a caliber between 100mm and 125mm. The said gun must be capable of firing a wide range of different projectile types: at the bare minimum, it should have ammunition specialized for dealing with hard targets such as opposing tanks, or soft targets such as infantry.

Historically though, this was not always the case. The very first tanks, like the British Mk.IV and the german A7V didn't really have a primary armament but were bristling with guns and machine guns. Initially, side-mounted sponsons were adopted for carrying armament because they could aim downwards into trenches. Obviously, as soon as trenches fell out of favour, so too did sponsons. Additionally, as an enemy tank will never be in said trench, mounting an anti-tank weapon in the sponson is utterly retarded.

The first ones to figure out the 'definitive' solution as described above were the French with their Renault FT-17 (pictured above), the very first to adopt a turret for the main armament of the tank. While the FT-17 was plagued by a host of teething problems, its overall design was so efficient and cost-effective that absolutely everyone jumped upon the bandwagon at the end of WWI, and (almost all) the rest is history. Indeed, at one point all nations toyed with the idea of multi-turreted tanks or land battleship concept, whereby a tank would have multiple turrets each with their own weapon. The idea was that the tank could attack in all directions at once, but in practice, this led to horribly oversized monstrosities that were less efficient than simply building more tanks with the same armament, and the smallest bomb from a rickety airplane dropped in terminal velocity would obliterate it and ruin weeks of factory man, hours and materials. The madness then died down and coalesced into two main lines of thought right before WW2: The Americans, British, and French limited the number of guns to two on their heavier tanks, one bigger casemate-mounted howitzer to deal with infantry/pillboxes and one smaller turreted AT gun (see also Char B1, the early Churchills and the M3 Lee). The Germans on their side decided 'fuck it!' and just went for specialized tanks sporting either a small-bore long-barreled AT gun or a broad-bore short-barelled howitzer, and then just had both type collaborate on the battlefield (see early Pz.III and Pz.IV). And this went swimmingly for them, at least until the Russians finally entered the dance in 1941 and deployed the revolutionary T-34, whose 76mm gun demonstrated it was possible to have a tank gun both capable of tackling armour and blowing stuff up with explosive shells, setting the precedent that stands up to this day.

Once at that point, the overall design was definitively set and guns just got bigger and better from thereon. Starting with the Soviet T-62, they started to go from rifled to smoothbore guns. If you are in any way familiar with the development of gunpowder weapons, this may seem like a baffling decision, but there is a good reason. Anti-tank shot went from a simple lump of steel to sub-calibre munitions like APCR and APDS, as detailed on the cannon page. These essentially try to be better at penetrating by focusing more energy on a smaller area. A later development was APFSDS, the famous "Silver Bullet" or arrow-like penetrators which turned Saddam's tanks into ooey gooey explody Swiss cheesey. Likewise, they also started using HEAT shells, which are designed to use the power of a focused explosion to bore their way through armour; at one point, they were so effective that tanks were designed specifically around their use. Both of these munitions types actually suffered from the rotational forces imparted by a rifled barrel. For APCR, APDS, and APFSDS, rifling does not stabilize subcalibre rounds nearly as well; likewise, the shaped charge jet from HEAT shells doesn't hold together as well if it's spinning itself apart. Getting rid of the rifling solved a huge number of other problems: it made it easier to fire missiles out of the guns, and also meant that you could fire higher velocity projectiles without having to reline the bore more frequently. The main exception was HESH, which was essentially a shell full of plastic explosive that flattens itself against targets; upon detonation, it creates a shockwave that is transmitted through the material, causing it to break and shatter if concrete, or to spall off into deadly shrapnel if steel. The spin imparted by rifled barrels helps the explosive pat out more evenly, hence why it is still commonly used by the Brits in their tanks.

During the 1960s, there was an attempt to replace the gun with a missile or gun-missile system which... didn't quite pan out. The main problem is that to accommodate guidance systems, fuel, and all that jazz, missiles are a lot larger than an equivalent tank shell, which strictly limits the amount of ammunition that can be carried. Furthermore, limitations associated with the technology at the time (heavy and fragile hardware, minimum firing ranges) precluded their use on tanks. Future vehicles may carry railguns instead, pending the development of a sufficiently capable, lightweight power system and barrels that don't become slagged after like five shots or so.

On a sidenote:

That said, while tanks began to coalesce around the turreted concept many remained turretless and as the German StuG proves, were successful weapons in their own right. The lack of a turret does have some advantages thanks to how it lowers overall profile and allow for a larger gun to be mounted than could otherwise be the case. That said, a turret-less tank is only really useful if you don't have the money to make a turreted tank, don't have a bigger tank for your bigger gun, and will only be fighting on the defensive. The latter is the reason why the only guys ever serious about turretless tanks after WWII were the Swedes with their Stridsvagen 103, and the Germans, with their Kanonenjagdpanzer 90. Even today, many SPG's are still built turretless, however those 'support vehicles' aren't considered proper tanks as they lack both the armor and the tactical flexibilty to act as one.

In addition to the main gun, you also have the following secondary weapons:

• Machine guns: They've been around since the beginning, in some cases serving as primary weapons, and they're still around as secondary weapons on most armoured vehicles. They can be mounted pretty much anywhere: on the front of the hull, in its own turret on the hull, in the commander's cupola, on the side of the hull, on the back of the turret, beside the cannon (coaxial), or on top of the turret next to the hatch. The latter two are preferred for modern tanks: the coaxial can easily be used by the loader or gunner without having to change stations, and the top-mounted gun can be aimed pretty much anywhere around the tank, including at aircraft. Either medium/general purpose machine guns or heavy machine guns are preferred for firepower and rate of fire sustainment usually as one GPMG on coaxial and a heavy on pintle (with some taking a GPMG pintle), though it's not unheard of for some crews to slap on a couple extra mgs of any variety including light machine guns/squad automatic weapons. The French take a coaxial HMG and both a GPMG and a HMG on the pintles, while America has two GPMGs (one coaxial one pintle) and two HMGs (both pintle) because Murica.
  • Crew Weapons technically count as well as it's not unheard of for some crews to take potshots with SMGs or Rifles they are issued from the hatches or from purpose built fireports.

• Autocannons: The next step up from machine guns. Like machine guns, they've also served on primary weapons on more than a few tanks. After the Second World War however, they've tended to be relegated to the status of secondary armament, with potential use against light armoured vehicles and helicopters. Despite their obvious firepower advantages, most tanks don't have them, on account of being rather cumbersome and requiring a separate ammunition supply. The only places where you could feasibly mount them are coaxially alongside the main gun like the French AMX-30; otherwise, you'd have to create a separate compartment somewhere on the turret or hull, as was done with the experimental MBT-70, which had a retractable cupola for it.

• Grenade launchers: While tank cannons may fire high explosive shells of greater potency, an automatic grenade launcher has similar flexibility to a machine gun in urban environments, only with more firepower. Another form of grenade launcher is the smoke projector that many tanks incorporate as a defensive measure, but that's for later discussion.

• Mortar: Like the grenade launcher, a mortar on a tank can be handy for fire support. The Aussies took a page from the Germans' "mad genius" book and mounted a 7-rounds 178mm spigot mortar on the back of a Matilda II tank, the idea being to give their infantry support tanks some serious close-range firepower for those cases something needed to be softened before an assault. That said, it didn't really take off: there were much more efficient ways of providing fire support separate from a tank, and the only reason it was worth bothering with was because many early-war British tanks of that period (like the Matilda) had extremely poor or even non-existent high-explosive shell capability. Nowadays, the only tank to feature a mortar is the Merkava, which largely serves as a utility weapon for firing special munitions such as smoke or illumination rounds.

• Rockets: During the Second World War, a lot of countries experimented with mounting rockets on tanks, ranging from the various German Nebelwerfer attachments or the Calliope mounted on the American M4 Sherman. Like with the example of the Matilda II above, the point was to provide fire support in anticipation of an assault, or otherwise simply reuse obsolete tanks. They fell by the wayside for similar reasons, or were re-invented as dedicated artillery vehicles (like for instance the TOS-1 Buratino).

• Guided missiles: While attempts to use guided missiles as primary armament in tanks have largely failed to succeed (with one exception), they are still being developed as a special munition designed to be launched out of the main gun. This provides tanks with an option to engage targets that are difficult to hit at distance with their main gun, which can include helicopters. Lighter tanks like the M551 Sheridan typically use guided missiles to give them an extra anti-armor punch when needed. Similarly, old Soviet tanks like the T55AM2 are upgraded to fire advanced missiles as a way of extracting more usage from obsolete but otherwise functional equipment.

Defense

In general, tanks are designed to maximize their protection for a given weight. Initially, the only criteria during World War I was that tanks should be bulletproof... which they were, to some extent. While their armour might have been thick enough to deflect most bullets, poor quality steel and riveted construction meant that tank crew tended to get injured anyways by pieces of steel breaking off from repeated impacts. They also did jack squat against artillery, large bundles of grenades, poison gas, and flamethrowers; later in the war, the Germans developed special armour-piercing bullets and anti-tank rifles that could punch straight through.

Fast forward to the Second World War. Early on, you still had tanks that were so poorly armoured that they could be easily pierced in several places by heavy machine gun fire or special anti-tank rifles. As tanks got bigger and more capable however, they started to incorporate not only thicker, welded armour, but also a technique known as sloping. Basically, what this involved is the angling of armour plates to increase their line of sight thickness, so a 45mm plate angled at 45 degrees relative to an incoming shot would effectively have a thickness of 90mm; slanting the outer surface such that the anticipated trajectory of incoming projectiles will not hit it perpendicularly also increases the likelihood that they will deflect and only deal a glancing blow, instead of penetrating the hull before detonating. This technique was not unknown before the war, but the size limitations of earlier tanks made it difficult to implement, as sloped armour ate into usable interior space; it was also a little harder to build than just slapping everything together at right angles. Of course, then the T-34 came along and showed that sloping could make plates of even modest thickness repel any early or pre-war anti-tank weapon, and then on sloping became an integral feature for almost all tanks.

All seemed fine and dandy until some assholes started knocking together something called a shaped charge onto lightweight launchers that a complete bunch of nutters could use to take out a tank, creating weapons like the American M1 Bazooka or the German Panzerfaust. At some point during the Cold War, the increasing effectiveness of shaped charge weaponry made some designers throw up their hands and give up on providing maximum protection to their tanks. If the thickest armor you can put on a tank is going to get penetrated anyway then your best bet is not to armor it at all and focus on maximizing speed and minimizing profile to make sure you don't get hit to begin with. The German Leopard 1 and French AMX-30 were designed according to this principle, when it seemed like it would be impossible to defend against new HEAT shells. Others kept experimenting, and by the 1970s, people developed measures to deal with them, starting with the well-known principle of spaced armour, and then moving on to quartz and ceramic plates.

Nowadays, most modern tanks have good protection all around from most weapons, with a particularly heavily-armoured turret and front to resist dedicated anti-armor weapons. Most modern tanks have some form or another of composite armour, which consists of layers upon layers of spaced steel plates, ceramic tiles, kevlar liners, and so forth. The idea is that by putting these various materials together, you can achieve greater protection against most things for far less weight than an equivalent protection level of steel, though it does become quite bulky. How these materials exactly work together is not entirely known to even the most pretentious armchair generals. What can be said, however is that there are two big ways to defeat armour: punch through it with enough force (and, for an added treat, explode inside after that) or smash it with sufficient force it shatters and the debris ravage what is behind (somthing called 'spalling'). Thus, modern composites deflect brute-force projectiles away and have spall liners woven throughout to prevent spalling from killing the crew.

Below are a few devices and techniques utilized for defensive purposes:

• Smoke Dischargers: The little pipes or beehive-like clusters you see on the turrets and hull of the tank are smoke launchers, which fire a single salvo of smoke grenades upon activation. You may find the idea of trying to hide a tank ridiculous, but a good tank commander will know how to use smoke to mask their movements in case they need to make a hasty retreat, or to cover an advance into a more favourable position. However, they're also really, really good at fouling up enemy sensors (anywhere from optical to infrared) and guidance systems. Even a few moments of obscuration to the enemy tank's gunner can mean the difference between life and death.

• Camouflage: Because the best defence is often not getting spotted until it is too late. Visual camouflage in the Second World War was extensively employed to either make them more difficult to spot or to obfuscate their silhouette. For the former, tanks would be painted in colours that helped blend in with their background; netting, foliage, and/or debris may be incorporated to complete the look. The latter works by deceiving the enemy into thinking that the tank they're seeing from aerial reconnaissance is actually a truck, or that the tank over there does not have a gun capable of turning your tank inside out. Dealing with non-visual spectrums such as infrared or radar detection require the use of special materials or paints that make tanks harder to pick out of the background.

• Reactive Armor: As per the name, they are designed to react to incoming projectiles. The most common form is what is known as Explosive Reactive Armor or ERA: essentially metal boxes with a small explosive charge sandwiched between two metal plates. When a sufficiently large projectile hits an ERA tile, it detonates, forcing the metal plates apart; this can disrupt a shaped charge jet before it has time to form. Later versions like the Russian Kontakt-5 and Relikt are capable of defending against APFSDS munitions by forcing the penetrator off course, dissipating its kinetic energy. In addition, there is also what is known as Non-Explosive Reactive Armour or NERA. Instead of an explosive charge, NERA incorporates an elastic material that is wedged between the two metal plates. Like ERA, it will react to attacks; however, instead of exploding, the sandwiched layer will expand, with similar effects on incoming projectiles to ERA. Compared to ERA, they have the distinct advantage of not exploding, which makes them safe to use around infantry, so they tend to be more like easily-replaceable armour tiles; modern-day composite armours may also incorporate them into their defence arrays to varying extent.

• Slat Armor: Due to how shaped-charge rounds work, they need to detonate at the right distance of the armor to punch through it. Something as simple as a metal cage surrounding you can prevent the shaped charge from doing much damage by just making it go off early or warping the detonator upon impact, rendering it useless.

• Improvised Armor: Just like its name says. During the Second World War, tank crew tried to bulk up armour with whatever they could find in the field. These can take the form of salvaged armor plates from other tanks and bedspring mattresses, or nothing more than basic materials like sandbags, wooden logs, or ooncrete. Ironically, many of these materials were probably worse than nothing: the added weight overstressed components and slowed down whatever tank they were mounted on. Moreover, due to defects in HEAT design at the time, they may have actually enhanced the effect of the warheads by causing them to detonate at the optimal distance, away from the tank's main hull.

• Active Protection System: An active protection system is a device that shoots down or deflects incoming anti-armor projectiles. It takes two forms. The first is an electronics countermeasure system that detects incoming guided missiles and attempts to trick them into not hitting the tank, usually by messing with their guidance systems. The other type involves an active radar scanner linked together with a launcher or projectile weapon of some sort; when it detects an incoming projectile larger than a bullet, it calculates its incoming trajectory and then fires a projectile which destroys it mid-flight. Like reactive armor, it’s usage is restricted from general deployment due to costs or concerns on the risk of collateral damage to civilians or allied infantry.

• Spaced Armor: Spaced Armor is what it sounds like. Armor with a large gap. This gap helps dissipate the shaped charge. The most obvious examples are goofy-looking thin plates around a WWII German tank's turret and tracks (Schürzen or skirts). Although they were initially designed to deflect light AT guns and rifles, they may have had some effect against HEAT warheads, at least according to some people. Whatever was the case, it has been well-established that trying to force a shaped charge to travel through three feet of air will protect a tank far better than a foot of armour. Usually incorporated as one aspect of modern composite armour.

Mobility

Another major aspect of the modern tank is mobility. While early WWI behemoths like the British Mark I and the German A7V were content to lumber slowly forward with all guns blazing at the enemy, the need for higher speed and better cross-country capacity soon became apparent. Mobility in general is dependent on four major components, namely: the tracks, the suspension, the transmission and steering mechanism and the engine itself.

• Track design is as integral to the identity of a tank, as it allows it to move around without sinking into the ground. Modern tracks are so good at their job that a tank imparts a lower ground pressure (or weight per square inch on the surface) than an automobile tyre or a human foot. That said, they are a also a significant weak spot: they can break or slip off, leading to a complete loss of traction, and a stopped tank is a dead tank. Nowadays, tracks often use the so called "slack-track" approach: a number of road wheels low to the ground transfer the weight of the tank to the track, two sprocket wheels (one in front and one at the rear) transfer the motive energy to the track and a couple of return wheels on top keep the whole track tense while in use. (Other arrangements have been used historically, but they fell by the wayside due to either fragility, or being too maintenance-intensive.) Efforts are made to keep the height of the whole track assembly as low as possible, as no matter how cool the British Mark I looked, running the tracks over the top of the body is begging for a mobility kill. (Though to be fair to the Mark I, it needed its high tracks to cross trenches, and since it came first, there weren't really any weapons that could specifically take advantage of its exposed tracks at the time.)

• Even more than the tracks themselves, suspension is what allows tanks to travel easily over all terrain, absorbing all of the bumps and lumps. The earliest tanks did not have any suspension. By the Second World War however, you had vehicles using varying arrangement of helical and leaf springs to smooth the ride out a little. Most tanks now employ what is called torsion bar suspension, which translates the up-and-down movement of the roadwheel into a metal bar designed to resist twisting. A few newer models employ hydropneumatic suspension, which can be adjusted to cope with softer or harder terrain, as well as adding a few more degrees of elevation or depression for aiming the main gun.

• Transmission and steering of a tracked vehicle is quite complex in execution, however it is conceptually quite simple: turning is accomplished by accelerating one of the tracks and slowing/stopping the other one. While there have been many different combinations of engines/driveshafts/clutches/brakes to obtain this since the first WWI vehicles, modern tank design boils down to two concepts: Russian/Chinese ones favor two separate transmissions, one for each track; while Western ones prefer the so-called 'double differential' approach that adds a second driveshaft and idler sprocket wheel to each track that can be used to speed/slow it. One big advance of the modern tank (and tracked vehicle in general) is the so-called 'neutral steering' that allows the tracks to turn in opposite directions and the vehicle to easily and quickly turn on the spot, something a wheeled one would be hard-pressed to accomplish as quickly and smoothly (if at all).

• As for the engines, most tanks designed prior to the Second World War but after the First World War utilized the same engines as trucks and buses (cheap but underpowered), while a few settled on downrated airplane engines (lots of power but unreliable). At the start of the war, only the Germans dedicated engine production for military vehicles (which led to problems that we won't get into here) but it was the Soviets who would later take the cake, with the relatively lightweight yet powerful diesel Model V-2 in the T-34 (seeing a pattern here?) that would go onto to power almost all of their tanks. Most tanks nowadays go for diesels but a few use turbines. A diesel has the advantage of being fuel-efficient but with a rather poor power-to-weight ratio, while turbines run on nearly anything flammable and have much better power-to-weight ratio and are quieter, but are very thirsty and their much hotter exhaust can present some trouble to camouflage the vehicle against IR sensors and hazard to accompanying infantry. In the interest of making warfare more environmentally friendly, we may eventually see tanks driven by electrical power and hydrogen-fuelled turbines.

By nature, tanks have some wading capability, capable of going through water that would stop your average automobile dead. To go through deeper waters usually requires extensive modifications. The first truly amphibious tanks for instance, required canvas screens to be attached for flotation, along with a propeller driven by the tank's own engine. Presently, a few tanks, most of them Russian, have the capability to be driven completely underwater, provided that they're provided with a snorkel.

Support

In addition to the essential three attributes of offence, defence, and mobility, tanks rely on a whole host of systems to be tanking. While none of them are strictly speaking indispensable, those extra systems are what turn a tank from a mobile pillbox fighting on its own into a force multiplier able to support their fellow soldiers and efficiently outmanoeuver and take out what has the misfortune of being in front of them. Any modern tank design will weigh the pro's and con's of outfitting the vehicle with said systems. Where including some systems are a given, other's aren't - it will often boil down to intended use, economics, and local limitations.

• Communications: The most vital improvement on this list, it comes in two distinct parts both equally important.
  • Internal Communication An intercom is extremely important inside a tank because, well, tanks are LOUD, and it's the only way for the crew to talk to each other without going hoarse yelling at each other. And it's not a joke: before the advent of intercom the commander often had to kick the driver on the left or right shoulder to indicate the direction he wanted him to turn because even yelling wasn't working with the ruckus of the moving tank. Modern intercoms often have double and sometimes even triple-redundant systems, because it is that important for the commander to tell his driver where to go and his gunner where to shoot.
  • External Communication Another not be overstated improvement is keeping in touch with other tanks as well as whoever is in charge. Having a system to coordinate multiple units determines whether or not a tank is a rolling pillbox or a decisive, mobile weapon of war. Inter-war tanks often relied on flag signals with only the company leader having a radio for coordination, but in the early thirties some guy named Guderian ordered "Each vehicle must have its own radio; no exceptions!" and the rest is history. Indeed, in both the battle for France and the early Operation Barbarossa the German tanks were outnumbered, undergunned and underarmored compared to their opponents but thanks to their radios, they were able to outmaneuver the enemy and take them apart. (Conversely, during the Battle of Britain, the Luftwaffe failed to similarly radio-coordinate their fighter planes whereas the RAF did, giving the British a very significant advantage.) Cue everyone doing the same (even if Soviet tank crews actually communicated mostly in kicks and flags until well into 1943 because early Soviet radios were shit tier and tended to break in the first minute of every goddamn engagement), and still doing it today. The major improvement modern communication systems have brought is the ability to transmit not only voices but also data, which makes keeping everyone informed of the whereabouts of one's allies and enemies much faster and easier. Since WWII, many tanks also come with a built-in wire phone in an armored box on the back called the “tank-infantry or grunt phone” for infantry to talk directly to the tank commander for fire support and coordination of combined arms tactics. This may seem redundant with the use of wireless walkie-talkies but is a godsend in the case that airwave frequencies are jammed and the platoon commander needs to direct the tank to provide armored cover and supporting fire for infantry in a chaotic firefight without rolling over their allies.
    • IFF Piggybacking on the improved communications and electronics of modern vehicles, the "Identification, Friend or Foe" system is basically a nifty little system that transmits a 'I'm a friend, don't shoot me.' signal to any other unit in the vicinity when queried and (if all goes well, for it is not always 100% reliable, especially amongst multi-nation task forces) will prevent friendly fire incidents. A simpler version of this would be IR identity stickers posted on the hull for aircraft to see from afar or RFID tags that can be read with the right scanning equipment. OR, if you're Russian, just covering your vehicles turret to track in hastily spraypainted "Z"s to tell the other conscripts not to shoot at this particular T64, and tell the Ukrainians to line their Javelins up.

• Detection: Tanks have notoriously bad situational awareness, so people came up with solutions to improve it. The most basic instrument is of course, Eyeball Mk. I, initially relying on either vision slots, optical instruments such as periscopes, or the commander poking his head outside of the tank. In WWII, the Germans installed an armored cupola with vision slits atop the turret in order to improve the commander's sight while 'buttoned up'; near the end, they also came up with primitive infrared illuminators as well. Nowadays, you have an array of cameras, night-vision, and infrared/thermal imagers to give you a clearer picture of things. Some tanks also have an automated laser warning system to detect when enemy vehicles have painted them with a rangefinder or are locked on by a homing weapon. Once it detects the laser, it will warn the crew and taken defensive actions such as using smoke grenade launchers, active protection systems, or laser jammers. Lastly, many militaries rely on combined arms use of reconnaissance units (in the form of light vehicles, mounted infantry, aircraft, or drones) to screen the area ahead of tanks to minimize the risks of ambushes.

• Fire Control: Another big chunk of tech, fire control includes any and every system meant to improve the main gun's accuracy and reduce the time between identifying a target and actually blasting it to smithereens. The first tanks did not have really anything like a modern fire control systems. However, when it became clear tanks would be called upon to deal with other tanks, improvements were sought in roughly three different and complementary directions: improving accuracy at longer ranges, improving accuracy while on the move, and improving accuracy when firing at a moving target. There are many historical attempts to achieve this; below you'll find a list of the most common historical ones, all culminating in the modern computerized fire control system.
  • Sights: By the outbreak of WWII, tanks commonly used telescopic sights with stadiametric indicators for ranging; think a rifle scope, but adapted for the tank's gun. The indicators allowed for a precise compensation for the target's range and movement, however the scope by itself had no way to measure said values; and those were often left to the crew's experience, pre-battle reconnaissance and educated guesswork to determine.
  • Ranging Shot: Laugh if you want, but an experienced gunner could use a quick burst from one of the tank's machineguns to make a decent estimate of the range to target and quickly compensate for the follow-up shot from the main gun. Sure, it was crude, but it worked pretty well for what it was. The British went a step further and attached ballistically-matched spotting rifles to their tank guns, where firing solution was confirmed by a tracer impact on target (the American M60 'Ontos' did it in 'nam as well).
  • Rangefinder: Battlefield experience from WWII impressed upon military commanders the importance of ensuring the first shot fired at an enemy tank hit, denying the enemy the ability to react to a missed shot. As tank warfare rolled into the Cold War, so-called "first-shot accuracy" became a priority for tank designers, who once again took a page from the navy and started mounting dedicated optical rangefinders to their designs. These devices allow crew to determine the range of a target, without having to leave their positions inside the tank. Rangefinders were considered a huge improvement, and quickly became commonplace. Modern ones are laser-based, computerized, and far quicker to operate.
  • Stabilizer: Essentially, this is a mechanism for keeping your main gun pointed in the correct direction while the tank is moving. While these sound great in theory, initially they were not viewed as critical to tank effectiveness, particularly since early designs didn't work very well: in WWII the American M4 Sherman tank used a stabilizer which only compensated for vertical movement, and only at low speed. But as we've said earlier, a stopped tank is a dead tank, and moving makes it harder for you to be hit. As such, even the earliest iterations were useful as a critical time-saver: relieving the gunner of some of the burden of aiming after the tank comes to a stop to fire at a target. As WWII ended and the Cold War began, stabilizer designs continued to improve. Later designs provided stabilization for movement in the horizontal and vertical angles, and modern designs even accommodate for the vertical heave of the tank changing physical elevation as it drives. Stabilizers have become essential for modern tanks, allowing for accurate firing while on the move.
  • Ballistic Computer: A modern development allowing for the gunner to accurately compensate for the target's movement (and other factors if necessary), especially when his tank is moving as well. This is yet another adoption from the navy, who were already using mechanical targeting computers during the turn of the 20th Century. It required half of a century's advances in computing miniaturization to create a mechanical targeting computer small enough to be fitted into tanks. Mechanical rangefinders appeared during the early Cold War, and digital computerized rangefinders would be developed and used in the late Cold War.

• Autoloader: A mechanism for automatically loading shells into the main gun, obviating the need for a loader. This is less of an obvious decision than it would seem. For decades, human loaders were actually regarded as better than mechanical loaders because they were generally faster and better: most early autoloaders had to depress the gun to a minimum elevation before loading and had difficulty switching between different types of shells. An autoloader that is put out of action by mechanical failure or damage will either make the cannon more difficult to load by hand or at worst, render it entirely inoperable, requiring extensive repairs in order to be restored to fighting condition. Plus, as mentioned in the previous section, having a human loader lends versatility and redundancy to a tank crew, as the loader could function as an additional pair of eyes and hands whenever needed. Initially, the main advantage to automating the loading process was that you could afford to have one less crew member, thus reducing overall weight. Newer developments however, can easily match or surpass human loaders in terms of loading speed, with the additional benefit of never tiring.

Due to their desire to man more tanks for the same unit size (cutting crew from 4 down to 3), the Soviets went in heavily for carousel-style autoloaders, storing ammunition beneath the main turret. One unfortunate (but hilarious) drawback of these autoloaders is that in the event of a strike to the turret (especially by a top-down anti-tank guided missile), this will often lead to all of the rounds cooking off, blowing the turret off the tank and killing the crew (examples can be now found all over Ukraine). Newer style autoloaders, such as that used on the Leclerc, mitigate this concern with the use of blowout panels.

• Remote Weapon Systems The pintle-mounted gun is great for clearing out and suppressing infantry because it can rotate 360 degrees and is at the top of the tank, so it has a bird's-eye view of the area. Unfortunately, popping your head out to shoot at people makes you a prime target for snipers. A solution for this is having the pintle gun be virtually controlled from the inside by a remote weapon system, so the gunner can still shoot at targets without threat of catching a bullet in the face the moment they peek out of the hatch. Granted the gun itself can still be shot, but it's a lot easier to replace a machine gun than a trained crewman. The aforementioned blurb regarding replacing the MG with grenade launchers also apply here.

• Air Conditioning System/Climatization: Yes, I can already hear you laughing. First, watch this 30 seconds video. Then imagine having to ride/fight into a vehicle getting that hot for hours, you'll get the point. An airco is not strictly speaking mandatory, depending on where your tank is operating. But many modern designs include one by default, as it is an easy way to improve crew morale and efficiency.

• Automatic Fire Extinguisher Fire in the hull? No problem. Tap a button to activate some kind of extinguishing system in either the engine compartment or fighting compartment. Modern systems are automatic, in the case of the Abrams tank the crew just wait a few seconds and Halon gas at 7% concentration will puts it out.

• Damage Control: A big problem with tanks is them tanks going up from the ammunition being detonated when hit. The remains of the crew would be... messy, to say the least. Frequently they would be buried all together in a matchbox. So, once again, we came up with way to limit that happenstance.
  • Common Sense, Better Training and Improved Logistics: Early in WWII, the doctrine called for full combat load and crews tended to cram in a generous extra helping of fuel, ammo and spare parts in their tanks, "just in case". This turned their tanks into mobile explosion hazards (just imagine a Sherman chock full of over 120 shells, 5000 MG rounds, extra fuel drums lashed to it... you get the idea). To remedy this, combat loads were lowered, logistics were improved to make sure tanks could be repaired and resupplied easily, and crews drilled to take on no more than needed for the mission; which led to a marked decrease in such big booms.
  • Welded Armor: Toyed with by all belligerents, the idea was to weld extra armor plates on the outside of where the ammo racks were. Which was a double-edged sword: it added protection, but was also an unmistakable 'shoot here for full effect' sign. Quickly abandoned when it became clear guns would improve faster than armor.
  • Ready-Rack and Secondary Ammo Stowage: The idea here is that the gunner/loader only keep around 'a handful of shells' (between 6 and 10 shells depending on the tank) inside the turret in easy reach, and the rest of the ammo stocked in armored compartments near the bottom of the tank, where the tracks/wheels/transmission/engine would work as that much added armor. The reasoning being that if a shot was powerful to reach the ammo stocked there in the least vulnerable part of the vehicle, the tank was fucked every way to Sunday anyway; and the decrease in rate of fire when the ready-rack needs restocking was an acceptable drawback for the improved protection. This concept is still in use on modern Russian/Chinese tanks, who have a rotating ammo carrousel at the bottom of the tank.
  • Wet Storage: Ammo compartments surrounded by a reservoir full of a mix of glycerine and salt water that would flood the ammo compartment if breached and buy time for the crew to bail out by delaying the cook-off. Good idea that worked good enough (lowering the risk of a cook off by about 30% when first introduced with the M4A3E8 Easy Eight Sherman) but ultimately more hassle than it was worth, and dropped after WWII. But...
  • Blowout Ammo Compartment: The idea of 'wet storage', adapted for modern tanks. They're basically compartments that blow outwards when the ammunition is hit and begin to burn; they vent the bang away from the main body of the machine, thus saving the million dollar tank (and the squishy but almost equally expansive meatbags inside). Sure, the tank must retreat to restock ammo, a new storage bin and some tuning up; but it can still fight with a small repair... if your ammo storage compartment wasn't open the moment it was hit.

• NBC protection: Because war never ceases to become dirtier, modern vehicles are outfitted with a system that creates slightly more air pressure in the crew compartment than is outside, and circulates air through a filtration device to protect against airborne threats to the crew. Those broadly come in the forms of nuclear, bacteriological or chemical agents which may be lingering outside the tank.

Crewmen

Unlike a car or most combat airplanes, a tank isn't something that one person can fully operate alone (at least for today's standards). It is a large, complex machine that requires multiple people with specific tasks to keep it working. Never discount the importance of a well-trained crew, as they can be every bit as important as the selection of equipment. While technically feasible to operate a tank with only two people (a driver and a gunner, as was the case with the Renault FT), it’s much more practical to have more people per tank to divide the workload, especially since a successful tank battle is heavily determined by the time it takes to get off a successful shot. Early tanks were envisioned as 'landships' and had a crew of around ten men, but most tanks today have a crew of three or four, with some crewman having multiple duties to keep things as streamlined as possible.

• Commander The commander is the one who issues orders to all crewmen. Their main responsibilities for the tank are navigating for the driver, spotting targets for the gunner, and coordinating everyone to work as one well-oiled deathmachine. They're also the one who typically mans the hatch-mounted machine gun when needed. In modern times, they are also responsible for the radio, which gives them the responsibility of coordinating with other tanks or infantry as well.
• Driver Maneuvers the tank, but with a twist. Because the driver is typically near the bottom of the tank he only can see in front of him unless he sticks his head out of a hatch; his peripheral vision borders on the non-existent. Because of that, they have to rely on the commander for precise maneuvers when the tank is traveling at full speed. That said, it is still possible for a driver to maneuver the tank on his own (yay for vision slits and/or cameras). In modern times, they also double up as the crew's mechanic.
• Gunner Operates the tank's main cannon(s) and coaxial machine gun, again with a small twist. He's responsible for aiming the guns where they need to shoot and firing when appropriate. They can also double as a loader if one's not available. But because the gunsight is quite narrow they can only make fine adjustments on their own and so need the Commander to spot the target and give them the rough direction in which to point the gun in the first place for them to acquire it and blow it up. A tank typically only needs 1 gunner, but older models that have more than 1 main cannon (like the WW1 British Mark tanks) required a gunner for each gun.
• Loader Assists the gunner by loading the appropriate ammunition into the main gun. Loaders are less common in modern tanks due to rise of autoloaders these days, but older tanks needed them to perform efficiently and the extra man has advantages his own. These include helping in field repairs and helping fuel the tank up and in the Abrams' case manning a second pintle gun.
• Mechanic Responsible for fixing up the tank when it breaks down (well, the whole crew pitches in but he's the guy with the knowledge). In later years to ease space concerns; the driver typically doubles as the crew's mechanic.
• Radio Operator Operates the radio and relays any orders and communications with friendly forces to the commander. Due to advancements in radio technology; radio operators are no longer needed in modern tanks as the commander can do that on their own these days.

Tank Classifications

In spite of what many autists would tell you, there are no objective classifications for tanks. Militaries throughout history, especially those that design their own equipment, have experimented with (and adapted from other militaries) different designs, configurations and loadouts for their tanks. These are based almost entirely on their needs and combat philosophy at the time.

In general, the best definition for a "tank" would be: "fully-tracked, cannon in a turret, fights other vehicles." This would ironically exclude the earliest tanks and tankettes, while also including Turreted Tank Destroyers which many more autists will tell you are "NOT TANKS". This gets even more complicated when you learn that most tank chassis end up being adapted to serve other functions, like tank destroyers, impromptu APCs (Kangaroo APCs), engineering and bridge-laying vehicles, or guided missile systems built on older tank chassis but designed to look like another tank (but still isn't a tank). Consider as well that the doctrines of different countries could classify the same tank differently (American WWII doctrine would call the Churchill a "heavy tank", but the original WWII British designers called it an "infantry tank"), and it's possible that a country's modern doctrine would classify a tank differently than it's historical doctrine! The key takeaway here is to just go by whatever the designers/military intended for simplicity, keep in mind that most militaries had flexible definitions, and don't sperg out because some reporter called an APC a tank.

The modern catch all term for all purpose built and improvised combat vehicles, not necessarily tanks, is Armored Fighting Vehicle (AFV). Below you'll find some historical classifications and /tg/ related examples of both proper tanks and their AFV cousins.

Classes of Proper Tanks

• Male/Female A very, very early designation that only really applied to the British Mk-series of tanks from World War 1. These tanks have very little in common with their descendants, being little more than rolling bunkers. They didn't even have turrets, instead having sponson guns. The main difference between them is obvious, male tanks have cannons, and female tanks have only machine guns. In modern time however Gendering Tanks is completely obsolete since most tanks by definitions have cannons and it is generally pointless to use an expensive tank to not carry a large caliber cannon. A comparison might be drawn to something like the BMPT Terminator which has autocannons, grenade launchers and ATGMs but no cannon on a tank as being the equivalent a female, though this is a thin stretch.

• Tankettes Less of a tank and more of an armored clown car with guns; these were in vogue for a while in the 1930s. They're essentially a one or two-person tank, armed with machine guns, flame throwers, or anti-tank rifles and not designed to move much faster than the infantry around them (except for the italians, whose cute lil' buggers could reach a respectable speed). They're generally made to act as mobile infantry support or anti-tank weapons. Needless to say, this idea didn't stick because when even a high-caliber machine gun (which WW2 was rife with) could penetrate the armor of the tank, making it useless in straight-up combat. Only the Japanese extensively used them during WW2, which made some sense as most of their combat theater is in jungles that would bog-down full-sized tanks (Plus their doctrine emphasized more on air and naval superiority, with them island-hopping during their conquests). Tankettes however, were still fielded in limited quantities after WW2 due to their light weight that allowed them to be safely air-dropped, mainly for non-front line use like tank destroyers, AA guns, and recon vehicles. The only tankette still in use is the German Sedan-sized Wiesel, an airdropped scout vehicle. In effect, the smallest of the tankettes with a crew of one were an attempt to make an individual soldier into a one man tank to allow them to support their comrades. Sounds familiar, doesn't it?

Examples: Grot Tanks

• Light Tank Light Tanks are usually small, fast, and carry smaller caliber guns. Because of size constraints, they also have smaller crew sizes. Because of their small size, they're also significantly lighter, making them much easier to transport/air-drop. Historically, the transition from tankette to light tank is blurred, since most militaries developed some sort of light tank during the interwar years, then scaled up tank production from there, going from two-man tankettes armed with machine guns to three-to-four-man light tanks armed with smaller-caliber (less than 75mm) cannons.
  • Light tanks aren't universally fast and weak, though. Some of the early British infantry tanks were classified as "light" in comparison with their contemporaries, but were equipped with armor that was much thicker than their competition. The Sheridan light tank from the 60s was also armed with a 152mm cannon, a caliber much, much larger than anything mounted on WW2 Heavies (with one notable exception), and continues to be an exception even with today's MBTs.
  • Unlike their Medium and Heavy counterparts, light tanks have survived in some form or another to the 2000s, even to the present-day in some armies. Since modern tanks are less reliant on armor thickness, and gun caliber matters a little less when you can load a guided anti-tank missile into your gun (though shaped charge effectiveness still depends on ATGM diameter) or just bolt it externally, Wiesel-style, Light Tanks have seen a resurgence as fire support for marines and air-dropped units, as well as taking priority in high altitude or jungle areas where keeping an MBT operable is very expensive.

Examples: Siegfried, M551 Sheridan

• Infantry/Cavalry tank- A paired concept developed by the British and the French (but mostly the British, due to the occupation of France and all), Infantry and Cavalry tanks were the first attempt at diversifying tanks, classifying them by role rather than weight division. The Brits kept this system throughout WW2, and because they were classified by role, infantry and cavalry tanks don't fit neatly within the weightclass categories. In fact, there is an infantry tank for each weight category, including superheavy.
  • Infantry tanks would be used to support infantry, so they did not need to be fast, but they did need to be able to shrug off incoming fire and cross difficult terrain, so most were long and ungainly so they could be used as mobile cover and to cross trenches. In some cases, it was more important to be used as cover by infantry than having exceptional armor. Tank on tank fighting wasn't really a concern at this point, since most tacticians, even the Germans, believed that towed support guns would be sufficient, so early-war infantry tanks didn't have the large caliber long cannons needed to punch through their own armor. Examples: Churchill, Matilda II
  • Cavalry/Cruisers tanks were designed with mobility in mind so that they could exploit holes in the enemy's defenses and cause general havoc in the enemy's rear. Just like the infantry tanks, they weren't really meant to fight other tanks either and instead attack targets of opportunity like supply trucks, so their guns weren't all that powerful, either. Some attempts were made at making Cruisers just as tough as infantry tanks, and at first this was a losing battle as guns would simply get better and render all that work moot. However eventually the cruisers got faster and were armed with better performing guns. These developments eventually led them to design "Universal" tanks post WW2, which were fast, decently armoured, and had guns that could punch through anything the enemy had.

Examples: Cromwell

• Heavy tank - "Heavies" is a catch-all term for big, fuck-off tanks with loads of armor. They're what most people think about when you think "tanks", and most of the first tanks built fit this mold even before they needed to distinguish them. What all Heavy Tanks have in common is their role: take a lot of shots and shoot as much as you take. They saw their peak in World War 2, with some post World War 2 developments, but changing technology saw the entire designation become obsolete in favor for Universal/MBT designs.
  • Russia was the first to supersize their tanks. Their first attempts at "breakthrough" tanks were multi-turreted monstrosities (T-28, T-35) that had lots of guns but no armor, and were so complicated and redundant as to be useless. Their next attempt with the KV was much more successful, being practically impenetrable by German weapons when it was first encountered. But being a rushed design that prioritized armor over function meant that it would quickly become obsolete in favor of tanks that were easier to manufacture. Soviet heavy tank production culminated with the IS series, tanks that were equipped with largebore (85mm, very quickly replaced by 122mm, standard now, but massive at the time) guns and used steeply-sloped armor over raw thickness. These tanks were actually the impetus for British and Americans to abandon heavy tanks for Universal designs, since they weren't planning on facing the Soviet tanks head-on, but instead destroy them at range. The Soviets were designing heavies until the death of Stalin, when the lack of pressure from him and the popularization of ATGMs made heavy tanks moot.
  • Germany's experiments into heavy tanks also began with some multi-turreted breakthrough designs, but they quickly changed their minds when they encountered British and French infantry tanks. The Germans realized that what they needed was a tank that was at the same time heavily-armed, heavily-armored and with the mobility to keep up with the rest. The result was the Tiger 1 and it was successful in that it did exactly what they wanted (big gun, heavy armor, good enough mobility) while also scaring the shit out of its opponents. But it was also over-engineered and was so complicated that it became unreliable, was simply too heavy for many roads and bridges and costed a lot of hard to get resources to make. Heavy tanks, while cool and absolute beasts on the battlefield when used correctly, were faced very real technological, physical, and environmental limits; and the Tiger was (depending on who you ask) either close to hitting or already past that limit. On top of it, while the Germans got what they wanted they didn't really know how to use it. In the mind of the people responsible for revolutionizing warfare with the Panzer divisions, Tigers were basically a special operations unit. Sure, they destroyed enemy tanks like nobody's business hanging back and firing at long range, but couldn't act as an actual breakthrough tanks. Doubling down when encouraged by the perceived success of the Tiger 1, the Nazi's proceeded to make them BIGGER, to the point that they began making Superheavies that would never make sense in the real world.
  • The British and American heavies, on the other hand, were more reigned in, if for no other reason then both of them would have to put there tanks on boats to get them to mainland Europe. As mentioned, their Infantry Tanks were their heavies, and because they weren't trying to cram speed, armor, and gun into a single perfect tank, they were a bit more reliable than the German vehicles at the cost of giving up either speed or armor. Compared to the Soviets and Nazis they didn't go overboard with gun caliber, and instead settled for high-velocity 75-77mm caliber cannons that were 'good enough' against the vast majority of opponents. Should they run into anything requiring a larger gun; well, time to call in the tank destroyers/artillery/airforce. The Americans made one "Heavy Tank," the M26 Pershing, which was designated a "Heavy" because it would have filled that role if it ever saw real service in WW2 (it was also important from morale perspective) but by the end of that war it was demoted to "Medium" status because of how it compared against the IS-2.

Examples: Tiger 1, Churchill, IS-2

• Medium The most enduring class, Medium tanks are the most flexible, being much more capable than light tanks in a fight, but not as tough and cumbersome than heavies. Medium tanks were originally built with specific purposes in mind, rather than being generalists: During the Interwar period, the British divided their tanks between "Cruisers," which sacrificed armor for speed, and "Infantry tanks", which were meant to either support infantry advances, or hold the line as an anvil while the Cruisers maneuvered around to the exposed rear. The first infantry tanks weren't as crazy huge as the heavies that succeeded them, nor were the Cruisers as light and defenseless as the light tanks that preceded them.
  • For their part, after the Germans rearmed in secret, their arsenal was nothing but medium tanks. Just like the Brits, their tanks were specialized towards certain roles. Their Panzer IIIs were smaller and more mobile than the Panzer IV and built to fight other AFVs. Its guns, ranging from 30mm to 57mm, were adequate at the time for the job of killing trucks and punching tanks in the butt. The bigger Panzer IV did the same job as the Matilda as an infantry support vehicle, but was nowhere near as heavily armored (or slow for that matter.)
  • When they finally met on the battlefield, it was more or less stalemate. While the British infantry tanks were impenetrable from all but the closest ranges, the Germans could outmaneuver them and had superior fire-support. Of course, being early in the war, both armies went back to the drawing board, with Germany deciding to build heavy-tanks and up-gun the Panzer IV as a stop-gap, and the British doubling-down on their Cruiser-Infantry tank paradigm, creating the Cromwell and Churchill respectively.
  • While many wehraboos jack themselves off to pictures of Tigers in the mud, it was the humble medium tanks like the M4 Sherman and the T-34 that really won the war by the sheer dint of them being completely reasonable. It cannot be overstated how important it was to the war effort that the Allies put their resources into tanks that weren't struggling to even bear their weight, because rather than creating contrived solutions just to make their big caliber fantasy a reality, they settled for designs that were reliable, easy to produce and with 'good enough' performance. Sure, you may not have wanted to be inside the poor Sherman/T-34 facing off against a Tiger, but your comrades thank you for your sacrifice as they dog-pile on the tank that killed you and eventually win the war.
  • The difference in firepower between the T-34/M4 Sherman and the German heavies did not last, however. Being flexible and having tonnage to spare, engineers were able to mount better performing guns on their chassis. Though it took some time, when the T-34-85 and the Sherman 76's/Firefly finally rolled out they were more than adequate at challenging German heavies. Sure, the German still had the advantage in kill range, but dog-piling them was now even easier and less costly thanks to the better guns. Foreshadowing the new lap of the arms-race between anti-tank weapons and armor thickness, the Western Allies would continue to develop Medium and Universal Tank concept until the advent of the Modern MBT.

Example: M4 Sherman, T-34, Panzer IV

• Universal/Main Battle Tank - The advent of the MBT is ironic, because it became the standard when militaries realized that you can't mount enough armor to stop dedicated anti-tank weaponry on all sides, and front armor should be an absolute priority. As an example, M1s shrugged off direct hits from T-72s from the front during invasion of Iraq, but had to be upgraded with TUSKs so they won't be burned down by an RPG older than its' entire crew combined from the side. This realization came about at different times for different nations, and everyone had different ways of dealing with it. The Soviets, for example, continued to experiment with dedicated heavy tanks until the 50s (creating monsters that weighted as much as Tiger II in the process) so the Western Allies built guns to destroy it, and built the tank around the best way to use said guns. They are often separated by "generations".
  • The first British "Universal" MBTs continued to be split between a "medium" MBT for close combat (The Centurion) and a "heavy" MBT (Conqueror) for ranged combat, before eventually settling for the modern Chieftain with its iconic 105mm Royal Ordnance gun, the gun that was exported to the rest of the West. Interestingly, Brits are special unique due to rocking rifled barrels on their modern MBTs.
  • American design basically boiled down to capitalizing on what they had and continually improving it, only switching to the next generation when the last one was really no longer viable: starting with the M46 Patton and its multiple upgrades (the M47 and M48, upgraded versions of the M48 are still in reserve in many NATO countries), then the M60 and its multiple upgrades and eventually everyone's favorite dispenser of FREEDOM! and its multiple upgrades. Just never mention the MBT-70 project...
  • The Soviets made many, many different MBTs in response to advancing Western technology, but they were all pretty much just modernizations of the previous design. Steeply angled armor, low profiles due to people sitting on top of the ammo, autoloaders on later models, easy to operate even for conscripts and being dirt-cheap to produce. Thanks to how Cold War worked, they were lethal opponents to the previous generation of MBTs they were made as a direct counter to; and a manageable but not neglectable threat to the next one... as long as the crew was competent, that is.
  • Germans, when they got the chance to restart their own armament industry in the late fifties, realized that should WWIII arrive they would be first in line for another bout of being rolled over. So they designed their machines to give them the best chance of holding the line long enough for the rest of NATO to arrive. Both the Leopard 1 and the more modern Leopard 2 emphasize high firepower and high mobility at the cost of armor, and Rheinmetall-Borsig's Rh 120 gun has become a staple of MBT main armament all over the globe.
  • The French, in a display of irony are today pretty similar to the Germans: just like their ancient enemy they came later into the picture with vehicles that prioritized mobility warfare over attrition matches. And while many jokes were (and are still) made about their overall performance, you do not want to be on the recieving end of their AMX series or Leclerc's punishment. As of today, there are talk of a joint-venture between France and Germany for a successor to both the Leopard 2 and Leclerc.
  • Another feature you may notice in Universal to MBT tanks is that the turret gets larger and more elaborate as time goes on. Turrets would become the most well defended part of the vehicle, partly because if it got penetrated the ammo would likely blow, but also because ideally the only part you want exposed is the turret. NATO tanks were perfect for this "hull-down" deployment and could hit a Soviet tank before they could even consider rangefinding, while Soviet Tanks were very low to the ground and relied on slope and gun-fired ATGMs for extra range.
  • For defense, most Western tanks use some sort of Composite Armor. Composite Armor is much thicker than metal, but lighter and much more resistant against anti-tank weapons. Kinetic shells can shatter before they make it through, and explosives find it harder to melt their way through layers of different, non-metal materials. Composite Armor is the reason why all Western Tanks have that flat smooth look, because steep angles actually make Composite armor less effective. So yes, the Leman Russ makes some sense at least.
  • Soviet countermeasures relied on both composite armor (the T-64 was the first tank equipped with it) and Explosive Reactive Armor. Think of an ice cream sandwich, but the filling is explosives. When hit, the explosive detonates and (hopefully) disrupts the projectile. Since then, tandem charges were created, specialized two-stage missiles that trigger the ERA prematurely with a smaller charge, before delivering the bigger, main charge, which is countered by new-generation ERA, to the point of some engineers suggesting to mount three charges in one ATGM. Needless to say, it's a little excessive in a world where concepts like Javelin and NLAW exist.

Examples: Chieftain, M1 Abrams, Leman Russ (tank)

• Super Heavy Tank Superheavies were conceived in World War I, essentially using the term "landship" literally. Armed with giant cannons (sometimes multiple ones, and usually reserved for artillery or battleships) and armor plating so heavy you'd mistake it for a fortress; they were meant to be the ultimate line breakers. While some prototypes were fleshed out, none (except for the French Char 2C, although it arrived too late to be used in WW1 and was obsolete in WW2) were put into service because they were simply too impractical. They were often too heavy to be supported by most roads (and off-road would have been worse), and were a logistical nightmare since their engines guzzled gas like no tomorrow. There was also the combined problem of being so slow and so large that they were easy targets for artillery spotters and bombers and it was near impossible to hide in the field due to it's large profile, so it was easy to disable the tank even before it got into effective range (No matter how much armor you put on a tank, artillery designed to level structures will eventually turn it into an expensive hunk of scrap metal). Overall, commanders found out that it was much better to send out multiple medium/heavy tanks to do the job, than sending a single super heavy. Still, because the idea of a multi-turret warship on treads is universally hella cool, that didn't stop writers from including such weapons in the arsenal of their armies, just to show how powerful they are. Super-Heavy prototypes had cannons that could range between 120mm-280mm, with the Nazis having many of the more absolutely ludicrous designs *cough*Ratte*cough*Maus*cough*. At the end of the day, this whole concept ended up being a useless waste of money in real life, at least until technology improves sufficiently.

Examples: Baneblade, Maus

Classes of Not Actually Tanks

Despite having treads and a gun, the following vehicles are not considered tanks. The difference is that tanks are designed for frontline combat, while other vehicles with treads are designed to carry and support infantry (APC/IFV), bombard enemy positions with heavy artillery (SPGs), or act as general support weapon systems. Many of these vehicles are light enough to be deployed by aircraft, giving them an edge over tanks in response time to emerging threats. If it isn't a purpose built chassis, they are frequently based on the previous or current tank being used to simplify logistics.

• Armored Personnel Carrier APCs are light vehicles designed to carry infantry and not much else. They're usually given a heavy machine gun to support the infantry they're carrying into battle and to defend itself, but they're highly unlikely to have more firepower than that. They're designed to protect against small arms fire, not tank shells. Unlike IFVs, APCs are not expected to fight on the front due to their lackluster protection and armaments. However, they're sometimes also amphibious, something that the vast majority of tanks are not, allowing for both seafront assaults and quick getaways down waterways. Don't expect anything bigger than a HMG (that being under 20mm, usually also under or equal to 15mm) and a grenade launcher. Very rarely a low caliber (20 to under 25mm) autocannon may be present. May have a couple ATGMs (Anti Tank Guided Missile) to suppress the enemy but it isn't designed to stay in a firefight, an APC is first and foremost a transport.

Examples: Rhino, M113, Namer (notably, it is based on the Merkava, an MBT, and has unusually tough armor)

• Self-propelled gun (SPG) Vehicles armed with artillery weapons designed to bomb the enemy back into the stone age, ranging from howitzers, mortars, or missile systems. Typically built similarly to tanks, but sacrifice armor for their heavy guns since in normal circumstances they should be too far away to get shot at directly. Not to mention that some artillery pieces have a minimum range where they can drop their payload; thus, the SPG needs to put some distance between them and their target so that they can be in effective range. The advantage to having such artillery on an actual vehicle rather than being stationary, is that counter-battery fire can threaten static guns, while mobile guns can safely get out of the danger zone once they've delivered their payload. Self-propelled guns typically carry a 150+mm Howitzer, much larger than what any proper tank would carry. While mobile rocket platforms such as the BM-21 Hail or MLRS are more popular than Self-propelled guns and are capable of absolutely soaking an area in rocket spam, the SPG has the advantage of being able to sustain fire for longer periods of time. Besides that, most SPGs can also depress the barrel enough to engage something directly which can be useful in some situations (avoiding collateral damage, for instance). Do note that standard operating procedure for SPGs is to leg it like a little bitch tactically redeploy if the enemy close on their position: even if they carry a big gun, they are not front-line capable vehicles. Direct engagement is avoided even if a huge shell will ruin a punk's day just fine. May have a machine gun or two just in case (and theoretical anti-air in older models, mostly enough to scare them off with a burst of tracers), or an autocannon if the armed force is particularly passive aggressive and has money to blow on useless overkill.

Examples: Basilisk Artillery Gun, M109 Howitzer

• Self-propelled anti-aircraft gun (SPAAG) Tank-like vehicles armed with weaponry designed to shoot aircraft out of the sky to provide mobile anti-air cover. There are only three real ways to shoot a very fast moving aircraft out of the sky. First you can use as many rapid fire guns as you can to fill the air with as many bullets as you can and hope for one hit. Second, you can fire one big shell up into the air and at a certain height have it explode spraying shrapnel around it self to score the one hit you need, this are known as Anti Air Artillery, and are known in the English world by the name the Germans used during World War 2, flak. Both have been superseded by AA missiles which can track a target and put that shrapnel warhead closer to the target than just guess work and a slide rule can. Others use both guns and SAMs. As a sidenote, flak tanks (and half-tracks) equipped with heavy machine guns and small autocannons have a nasty reputation as being infantry trouncers as multiple barrels spewing lead at high speed will turn soft ground targets into mulch very quickly. Indeed, both the M19 MGMC and the M42 Duster were primarily used in this role despite having been envisioned as point-defense SPAAGs. That role had something of a heyday between WW2 and Vietnam, with the quad mount 50 cal M45's being nicknamed Kraut Mover and the twin 40mm's of the M42 being used to lumberjack VC hiding in treelines. Modern variants mostly have guided missiles and the BRRRRT variants are usually not mounted on tanks.

Examples: Hydra Flak Tank, ZSU 23-4 Shilka

• Infantry Fighting Vehicle Known as IFVs, these almost-tanks are capable of transporting infantry forces, while being armored and armed enough to be of support to the field, unlike light tanks. However, unlike true tanks, IFVs can't be expected to stand up to enemy armor. Modern IFV's can have anti tank missiles, but with their tin can armor, going toe to toe with a main battle tank is suicide and so it supports regular tanks or takes on enemy armor in emergencies. While APCs and IFV can share similar roles and armaments today, the main way to distinguish them is with their main gun: anything that has a main gun smaller than 25mm is classed as an APC, and anything higher is an IFV. IFVs are designed to stay and fight (though not toe to toe with enemy tanks) and act as direct fire support. Effectively, when comparing a squad with an IFV vs a squad with an APC, the later is an infantry squad with a transport, the former is a (light) tank that can dismount some of its crew.

Examples: Chimera, Razorback, most Land Raider patterns (albeit with the difference that they can hold their own against regular tanks just fine), BMP, M2 Bradley

• Armored Reconnaissance Vehicle In some ways they can be confused for IFVs in that these vehicles are similarly equipped and focus on mobility, and may even have limited troop capacities. But where they mainly differ is in doctrinal use: Armored Recon is mainly used to provide independent support to a recon team rather than support front-line troops. As such, troop carrying capacity isn't as necessary if it has any at all. See below the Infantry vs Cavalry Tank distinction as it can apply here as well, since modern cavalry units use such vehicles. Some IFV's share a base chassis with ARVs , those ARVs are usually called Cavalry Fighting Vehicles (CFV).

Examples: Salamander Reconnaissance Tank, LAV-25, M113 MRV, M3 Bradley

• Tank Destroyer Tank destroyers are specialist armor designed for one thing in mind: knocking out armor and not much else. Some are turreted, and some aren't. Most modern ones use guided missiles, all historical and some modern use cannons. What makes them not tanks is a matter of technicality. Tanks are designed for general military purpose (so useful for a range of tasks) while tank destroyers are for only one thing, destroying armor (especially on vehicles). After World War 2 we figured out that since tanks fought other tanks so often anyway tank destroyers don't really make sense so we upgraded the guns on regular tanks. While the role of “Light Anti-Armor Vehicle” was taken by ATGM carriers, which are mostly modified APCS and IFVs, have the ability to kill tanks while being very mobile and easy to transport. A handful of cannon-armed Tank Destroyers still exist, some tracked, others wheeled, but they're a rare breed. They tend to be considered for use with airborne troops in need of anti-armor capability (since a proper tank tends to be too heavy to airdrop) and for certain strategic mobility concerns, usually built by replaced IFV turrets with a cannon equipped one, practically making a wheeled light tank.

Examples: Destroyer Tank Hunter, Leman Russ Vanquisher, M901 ITV

• Assault guns Similar to tank destroyers, assault guns differ in one important way: instead of an anti-tank gun, they're armed with a anti-building weapon, frequently a howitzer. These tended to be fairly big and fairly heavy compared to SPGs, because they're made to get in close to heavy fortifications. After World War 2 assault guns became light air-dropped weapons to support airborne troops if they encountered hard targets. They are comparatively very rare in modern orders of battle. Most that remain are in the Third World (usually WW2 Soviet vintage, they made a LOT of things), but some nations use IFV's equipped with cannon turrets, effectively making wheeled or tracked tank destroyer assault gun hybrids.

Examples: Vindicator, Churchill AVRE

• Flame tank a tank (going from tankette to heavy, all types were used in WWII) with a werfer zat werf flammen instead of a big gun as main weapon. Only used in the 1920s-1950s as they were quickly rendered obsolete (it was more cost-effective and just as efficient to have standard tanks have a flamethrower as a coaxial gun), though incendiary weapons of various sorts are still used today, mainly in artillery roles. Typically unpopular with both forces using and opposing them for many reasons: the implications of this weapon were very harsh as the typical man-portable flamethrower has a range of 60 meters max (video games lied to ME?!) and their heavy mechanized versions could reach most of a quarter mile with their concentrated hydraulic spray of diesel fuel. Flame tanks were supposed to start with a "Wet fire", basically spraying the fuel without igniting it into bunkers or fortifications to get enemy units to realize just how hard they were fucked, really weren't protected from the coming blaze at all and in turn they would surrender before being cooked to death. Which a vast majority actually did when hosed with gasoline. The problem was that, due to either open fighting, soldiers that just wouldn't surrender or sadistic crews/commanders, the weapons were often fired outright the first time around to horrific physical and psychological impact on both sides - burning, screaming soldiers, the fumes making crews sick, thick diesel smoke inhalation or oxygen depletion asphyxiating those in poorly ventilated areas (especially caves in the Pacific Front) and the smell of burnt human flesh permanently seared in their minds meant that instant life derailing post-traumatic stress disorder was a very common side effect of witnessing a flame tank in action. Another was that flame tank crews that were captured were usually subjected to torture and summary revenge executions. In the end, flame tanks are remembered as a job nobody wanted to do, an enemy nobody wanted to face, a weapon that accomplished little that soldiers using the man-portable variety (which already had a bad rep' but was begrudgingly tolerated by soldiers as tactically necessary to avoid chemical warfare, nobody in their right mind wanted to clear caves out directly) could not do and pushed the propaganda and soldier's beliefs forward that the enemy truly were barbarians and made of evil, all pushed ahead because a Commissa -- I mean General far removed from the field said they were necessary. Real life Grimdark indeed.

Examples: L3/35 "Lanciafiamme", M3 "Satan", M4 "Crocodile", Flammpanzer III, Churchill Crocodile, Kliment Voroshilov model 8, OT-34,

And finally, something of a special case:

What a "technical" looks like over history, as demonstrated in this meme photoshop.

• The "Technical", also known as "non-standard tactical vehicle" or "light improvised fighting vehicle". Essentially, just a pickup truck with a machine gun (or some other semi-portable weapon, like an anti-air or anti-tank weapon) mounted in the back. Originally named "Technical" because some of the first notable versions were hired by charities operating in very dangerous territories in Africa, and since said charities were forbidden from calling them "mercenaries", they euphemistically referred to the money used to hire them as "technical assistance grants". The Technical's most shining moment was probably the "Great Toyota War" of 1984, where Technicals, armed with precision anti-tank missiles from France, beat a Libyan force with actual tanks. Technically, counts as an Infantry Fighting Vehicle, but fills a distinct, unique role in modern warfare: the cheapest, frequently fastest to make IFV available to just about anybody with access to weapons and trucks, useful for projecting power and supporting infantry on the quick and cheap.

Examples: Too many to list, although a Toyota Hilux with an M2 Browning or DShK is probably the most popular Real Life combination, Goliath Truck

Tanks in Warhammer 40,000

Since Games Workshop seems to think that tank development in the Warhammer 40,000 universe stopped somewhere between the World Wars, most of the iconic fighting vehicles of the Imperium are a mish-mash of modern and historical designs. We can quibble that some of those vehicles are not really tanks but armored personnel carriers or other specialized classes of armored fighting vehicles, but GW's design team has a serious problem with looping their tracks all the way up and over the chassis for that 1918 flavor, and not even in the correct direction for what they were designed for. A variety of other vehicles in the 40k universe are referred to as tanks, but these are often hovering vehicles like those used by the Tau or Eldar, and thus technically don't count.

Real vs Fictional Tank Designs

Its important to know that games like WH40K subscribes to the rule of cool, rather than logic. So while things like the Land Raider or Baneblade looks cool; in a real combat situation, these tanks would range from highly impractical to down-right detrimental for everyone involved. Here's a short list of why real-world tanks, aren't designed like most fantasy tanks.

Profile

One of the main concerns of a tank designer has always been reducing a tank's profile as low as possible. This is for this main reason: it makes the tank harder to spot, and shoot at, at range. The others are mainly for mobility, like making the center of gravity lower so it doesn't flip over on uneven terrain, or smaller so its able to operate in various locales. Plus smaller tanks mean less material used, so that can be used on another tank or given to another project.

Sure it seems odd that this would be taken into account, given a tank is as large as a city bus; but since WW2: it wasn't really that hard to disable a tank (rocket launchers, mines, anti-tank guns, AT grenades, aerial bombers, artillery, better concealed tanks, to name the most common), if your opponent had the weapon to do so, and if they didn't: making a tank unnecessarily large just made it easier for your opponent to spot you. Thus, making your tank's profile as low and small as possible, contributed in making it less of an easy target, while still being able to act like a priority target for your opponent.

As with so many other aspects of tank design, there is a trade-off involved. Making a tank too small can compromise its ability to function as intended on the battlefield. Interwar tankettes were the most extreme example of this, with some that were smaller than the average automobile but lacking armament more powerful than a machine gun and armour that could protect against the same. With larger tanks, you could still run into similar problems by simply not leaving enough space for sufficiently powerful armament or engines (a problem which plagued many British tanks during the Second World War) or by making it too cramped for the crew to efficiently work with (which is common to many Soviet tanks before and after the Second World War).

Speed

Like what we've described above: it wasn't that hard to stop a tank with the proper armaments (or at least avoid it once spotted) and once your opponent has the guns to stop it, your hulking behemoth will slowly turn into a liability soon enough. (And even if they didn't have the guns; that makes your tank too-slow of a threat, which begs the question as to why you have it there in the first place).

Tanks were also pretty vulnerable on their own, requiring infantry support to deal with targets at close range (the co-axial gun only had limited elevation and was slow to aim as the entire turret had to face the target, and the pintle-mounted gun was limited to the line of sight of the gunner) as a nutter with a powerful-enough explosive could easily run/sneak to an unsupported tank and blow it to smithereens, or disable it (which pretty much meant the tank is still toast).

Nazi Germany got around this problem by using mechanized infantry (troops transported in vehicles) to support their armored forces, so everyone picked up on that and started making tanks fast enough to keep up with infantry transports to create a combined-arms assault, allowing tanks to deal with hard targets while infantry dealt with other targets that were too small for the tanks to take care of.

So, people started distancing themselves from heavyweight tanks, and started using lighter, but more faster tanks in modern combat (plus advances in modern technology made it that even a medium tank could still be as survivable and powerful as a true heavy, while still retaining maneuvrability).

Mobility

An immobile tank, is a dead tank, so people have gone to great lengths to either reduce, or outright remove the many ways on how infantry could disable a tank from moving; but the most common of this is by taking out the tracks with mines or explosives. This was partly fixed by putting the tracks at ground level, covering the tracks with armor, and adding additional armor skirts to further guard it from attacks from the side, ensuring that little of the tracks were exposed to direct enemy fire. Sure it was still vulnerable up-close and mines can still do a number on it, but that's what your infantry support is for (you did bring them, right?).

While the British Mark 1's rhomboid-tracks looks cool; having that on a tank today made it incredibly easy for an opposing force to disable your vehicle, as the tracks could be easily targeted. Plus even if you were to cover it in armor; it made your tank unnecessarily bigger, and people wanted to make their tanks as low and small as humanly possible. It also made maintenance and repairs unnecessarily complicated (Have to repair the tracks? Too bad, now you gotta get on top of your tall tank to fix that. Hope snipers aren't watching.).

Also while the sponson-mounted guns look cool, they're useless in modern tank combat. Apart from the obvious issues of being unable to bring your full-firepower to bear if your opponent isn't situated right infront of you AND that they have to be larger than the width of your tank: having two of your sophisticated weapon systems near ground level meant a plethora of reliability issues (went through water or muddy terrain? Pray to the Machine God your gun doesn't malfunction if you didn't clean that right away. Went through a building? Hope all that rubble didn't tear off anything important.).

Also note that this setup was done to for trench and fortification clearing, not tank vs tank combat (since WW1 focused on trench warfare than mechanized assaults). Having your turret in be centered with the hull itself, either with a turret or having it built into the tank itself to save on parts, was infinitely more effective. It also made weight distribution more balanced, which made it easier for tanks to maneuver in rough terrain.

Logistics

This should be an obvious point, but the Imperium of Man has only been able to create and maintain ludicrous super-heavy tank designs, because they have the aid of the Mechanicus (even if they've been reduced to a shadow of their former glory) to assist with creation and maintenance, plus having access to thousands of planets full of resources to get materiel and fuel from. Plus the creative liberties of simply accepting that "It just works" and "THE FUTURE", because it'd be boring if we had to explain that a Forge World couldn't build a Baneblade because some mining world couldn't produce the output or the resources for it were earmarked to other projects, rather than something more exciting, like foul traitors constantly assailing their supply lines, or the techpriests need some MacGuffin stolen by the Orks. After all, 40k is a wargame, not a convoluted bureaucracy simulator.

Another design point for tanks is resource economy. It had (and still has) to be produced using, and maintained with, the least possible amount of resources whilst still being formidable in it's role. If an army would deploy superheavies today, just remotely near the scale of how Imperial forces do during wartime; they'd be bankrupt and end up with a lopsided army. If creation didn't eat up most of their supplies; the amount of resources they'd need to keep these war machines maintained would put the US Army to shame. Once they realize they can't keep it up, they'd start scrapping those and scramble to turn them into practical tanks (assuming they still had fuel left).

It should also be noted that Warhammer 40k (or most military fiction for that matter) tends to focus on the cutting edge of warfare. We have far more images of Leman Russ tanks and the thousand varieties of Guardsmen than the logistical trucks or field kitchens which keep the Imperium's war machine functioning on a day to day basis. In escapist fiction people want to be Luke Skywalker rather than one of the the X-Wing mechanics at Yavin Base.

Armaments

Putting two cannons as your tank's main armament like C&C's Mammoth Tank looks neat and UNLEASHING ELEVEN BARRELS OF HELL sounds awesome, but that has its own set of problems. One is that putting a lot of main guns on your tank requires you to make the chassis bigger, as you need more room to accommodate the guns, ammunition, and larger engine (as you need more power to keep that sucker mobile), which makes it an even bigger target.

Another is that its a waste of resources; those other main guns, ammo, and materials, would be better put in making another tank, and two tanks are still more threatening than one. It is also either overkill, as the main guns of today's battle tanks can typically penetrate tank armor easily enough, or worthless since if you did meet a tank with armor too strong for your guns, having more of them is not gonna help. The probable rate-of-fire, firepower, or accuracy advantage you have over tanks with only one gun, would be easily off-set with autoloaders, specialized ammunition, better targeting systems, and/or a well-drilled gunner crew. That or an auxiliary missile launcher, which is loads more practical and cost-effective.

One more, is that in the event your tank is destroyed; that's a massive ammo-cookoff you're looking at, which can be dangerous to both the crew and surrounding friendlies.

The "Soft Factors"

Then there are a bunch of factors that can't quite be quantified, but significantly impact the quality of the resulting tank. Things such as "How quickly can you reload the main cannon *in combat conditions*?", "How hard is it to aim the cannon?", "How reliable is the engine?", "Why is it so goddamn hard to steer this thing?", "How much situational awareness can the tank commander have?", "How long does it take to repair?", "Does it have a radio? That you can use in combat conditions?" and so on. They heavily distort the quality of the resulting tank, yet are (mostly) really hard to fit on a data sheet.

Character Role

See also Combat roles for other roles

In many role-playing games, particularly the online ones, the term "tank" has also arisen to describe a character whose primary purpose is redirect all damage from enemies to himself. This was one of the primary purpose of actual tanks as well; tanks, being as armored and threatening, are supposed to get most of the enemy's attention while the squishier units like infantry and light vehicles move into advantageous positions to deal more damage, without the threat of serious retaliation.

See, many enemies in RPGs have way too much health, deal way too much damage for most classes to withstand, and fights with them are unlikely to be decided in one round unless they're uncharacteristically vulnerable to save-or-die rays (which almost never happens).

Furthermore, many of the classes that are best at dealing damage (assassin and wizard types, for example) often have very little survivability when it comes to being punched in the face, in order to balance out classes. If a class can both tank damage and deal high damage at the same time, they either render other classes redundant or can do neither as well as a dedicated tank or damage dealer. (This is where the gaming term differs from the historical/military term - a "pure" tank (unit role) is strictly something that attracts and survives damage, without much or even necessarily any of the punch a tank (vehicle type) has.)

Thus, demand is created for a character whose job is to redirect enemies' aggression away from the squishy members of the party and towards them instead, usually using their mastery of mind-control, irritating sound effects, imposition of dangerous effects for attacking anyone else, or simply cutting insults and rude gestures which draw attention to themselves. They also tend to have abilities that help them in resisting, mitigating, avoiding, or regenerating from some of the damage they suffer (and on occasion act as a secondary damage dealer). In most cases, tanks are also often reliant on healer classes as well to keep them alive while they do their thing, as enemies that require tanks can usually deplete a good chunk of their health in a few attacks. Making sure that chunk is constantly restored is required to make sure they can keep at it.

Fourth Edition refers to this role as the "defender," while Dawn of War 2 vets will recognize it as the "Tarkus", and later the "Diomedes." While it is most obvious in online video games, the necessity of drawing fire away from squishier party members toward tougher ones who can take a beating exists in a variety of different games, from cooperative card games to MOBAs. The wargame equivalent would be the DISTRACTION CARNIFEX.

See Also

• Team Yankee - a tabletop game that revolves around late Cold War tank warfare, with plenty of info on real-world tanks.

Vehicle Warfare
Combat Aircraft - Siege Weapons - Tank - Warship