Editing Tank (section)

==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:

# 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. 
# A turret to house the main gun, to allow the tank to shoot at targets without having to pivot the entire vehicle. 
# Good protection against most battlefield weapons, with a heavily-armored front face to defeat anti-tank weapons.
# 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. 
# Tracks with independent long-travel suspension for each roadwheel, to improve mobility. 
# 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)
# 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, [[Land Raider|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, [[Baneblade|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.

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On a sidenote:
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That said, while tanks began to coalesce around the turreted concept many remained turretless and as [[Wikipedia:Sturmgeschütz_III|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 [[Jaguar Jagdpanzer|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.
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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 [[awesome|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 ([[Pereh|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 [[Tankbustas|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 [[Creed|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 [[Wikipedia:Mark I tank|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 '''[[Noise Marines|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 [[Nazi|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 [[Ork|Russian]], just covering your vehicles turret to track in [[Administratum|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, [https://www.youtube.com/watch?v=x1rXLhow1Ro 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 [[Nurgle|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.