Why no more Heavy Tanks?

Why are Heavy Tanks not produced anymore, shortly after WW2 the Heavy Tank disappeared and it was basically replaced with the Main Battle Tank. Why was this case? And also what is a Main Battle Tank? Just a buzzword?
Cover design by vonKickass.
Cover Images: Танк Т-10 (T-10 heavy tank), 2021, by Vitaly V. Kuzmin,
www.vitalykuzmin.net/Military...
THE FIREBALL OF PRISCILLA shot fired on 6/24/57 as a part of the Operation Plumbbob series,
Photo courtesy of National Nuclear Security Administration / Nevada Site Office, Public domain, via Wikimedia Commons, commons.wikimedia.org/wiki/Fi...,
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our brains
00:00 Intro
00:10 Initial Question: What is a Main Battle Tank (MBT)?
01:22 Chieftain’s Answer
02:44 What makes an MBT? Part I
03:23 The first MBTs
03:58 What makes an MBT? Part II
07:15 Why no more Heavy Tanks?
08:17 Main Battle Tank - Term of Convenience?
10:48 What is an assault tank, breakthrough tank, heavy tank?
#HeavyTanks,#MainBattleTank,#MBT

[@grizwoldphantasia5005]

This sounds comparable to fighter evolution. Engines improved so much that fighters could carry bombs and be combined attack / fighter planes. F4U Corsairs coould carry 2 tons of bombs; F-4 Phantoms could carry 9 tons of bombs, more than WW II heavy bombers. Similarly, engine improvements allowed tanks to carry more armor and bigger better guns.

[@termitreter6545]

Tbh I think the multirole idea goes way back, it was even a thing in WW2. Fighters could act as Fighter/Bomber, your BF109 or Spitfire could carry bombs and drop them. Some light bombers functioned as recoinnassance or night fighters. There was generally a weird concept of heavy fighter/light bomber that had a lot of overlap. The modern "multirole" term usually comes from stuff like the F18 and F16, although im not quite sure how much different they are.

[@phunkracy]

The advances in metallurgy also allowed for lighter guns that could sustain immense pressures. 120 mm of M103 was a far larger and heavier gun than L-44 of Leopard 2 despite being the same caliber.

[@robertkalinic335]

@@termitreter6545 I think ww2 fighter bomber isnt really supposed to go for bombing mission but only hit targets of opportunity on patrol or help out ground units a bit since they are more likely to be around compared to specialized planes. F16 can go on pure ground bombing mission and do same or better job than A10.

[@colbunkmust]

@@robertkalinic335 A-10 isn't design for bombing, it's role is as CAS and tankhunter, which is a different role to perform, and one that is not performed better by F16.

[@davidchambers8697]

I'm not sure that is a very good analogy, given that the USAF has built specialized bombers, such as the B-1 and B-2, in the decades since the F-4 Phantom was built.

[@davidlisovtsev6607]

well the Soviet view was really different from this view. My grandpa served in a T64 units, they referred to themselves as "heavy tanks" or "breakthrough unit". In the past for that job you needed a heavy armor and a big gun, but with technological advancements you could see the "heavy tank" in the Soviet army evolve into a "breakthrough tank" such as the T64 or the T80, both optimized for breakthroughs while regular line units got the T62 and T72 in the era after the medium tanks ended. Soviet doctrine also somewhat supports this, as the T62 replaced the T55 in units, while the T64 was replacing the T10 heavy tank. TL;DR: don't ask why heavy tanks died, but how breakthrough tanks evolved.

[@yajamanvamsikrishna509]

Nice view

[@steeltrap3800]

Interestingly enough, the famous Tiger I arose in response to a spec from the German Army for a "breakthrough tank". Chieftain's video on the Tiger I makes that point and speaks to why they had issues in the field, namely that they were INTENDED to be used as a fist to break lines, then to be withdrawn and serviced in time to be shipped to the next place in which a breakthrough was required. I imagine you know this, but it is an interesting coincidence. As an aside, the first 1/72nd model tank I assembled was a KV-1 followed by an IS-3. Used to play 'Tractics', an extensive rule set for using 1/72nd model tanks, along with anti-tank guns and soldiers, in wargames on any large area (by which I mean a few square meters at least).

[@DrDeFord]

Or like the disappearance of heavy vs medium machine gun (at least as described by Ian)- could use a MMG in HMG roles, so why haul around a heavier gun?

[@selfdo]

Certainly the automotive characteristics of the T-64 are quite superior to the T-10. Interesting how the Soviet Army still hung on to them in reserve all the way to its breakup.

[@PalleRasmussen]

@@selfdo Ukraine is still using their improved version. They sem to have adapted tank, doctrine and necessity.

[@slaphappyduplenty2436]

“Danke für coming on our show, Chieftain. Let’s talk about main battle tanks” “There’s no such thing”

[@The_Viscount]

You mentioned the classifications of light, medium, and heavy being based on gun caliber not armor. This wasn't just in the Army with armored vehicles. The London Naval Treaty of 1930 codified a light cruiser as a ship of up to 10,000 tones standard displacement with a main battery measuring no larger than 155mm caliber. A heavy cruiser was a ship of up to 10,000 tones standard displacement with a maximum gun size between 155mm and 203mm. This retroactively turned designs like the Pensacola scout cruiser with 203mm guns into heavy cruisers despite lacking heavy armor. While most warships of the period were armored to resist their own guns at battle ranges, these redesignated heavy cruisers had heavy guns but light armor. Admirals had to be careful to remember which ships could take a pounding and which couldn't. Predictably, things didn't always go to plan...

[@elanvital9720]

The very first mention of the term MBT dates back to the October 1957 Tripartite meetings between the US, UK and Canada, calling for "A main battle tank in the general weight class of 25 to 35 tons" that is basically good at everything and can do every mission. It must be capable of seeking out and destroying the heaviest known enemy armor. Of course none of the tanks produced since then by the West truly met these weight requirements, especially not with all the qualities the tripartite group wanted.

[@CharChar2121]

Precisely. The main battle tank is a wet dream of someone who doesn't have one; he described a god-tier superweapon that did not exist at the time.

[@selfdo]

The Holy Grail of tankdom was that they could be readily airlifted. Twenty-Five to Thirty tons? Maybe an IFV, but no realistic battle tank would be that light. So they just made cargo airlifter bigger like the C-5. Just add fuel and lots of dollars/rubles.

[@willw8011]

Interesting, but the M26, M46/M47/M48 were already in the mid 40 tons weight and had 90mm to 105mm cannons before 1957.

[@selfdo]

@@willw8011 For awhile, the US Army classified its tank by the standard main weapon size...so the M41 Walker Bulldog, sporting the 76 mm gun, was that "class" of tank, generally thought of as "light" but hardly so at 25 tons. The M26/46/47/48s were all classified by the 90 mm gun they had, even though the weight started at 46 tons and increased to 50 tons...comparable to the Soviet "Heavies"! Until 1957, when both the M60, and shortly afterwards, the M48A5, there were no 105 mm gun tanks (the M48 being up-gunned in Europe with US Army tank regiments once the M60 was deployed to retain commonality of ordnance; however, most of NATO still had the M47 and they generally kept 90 mm guns on their M48s until both were replaced in front-line units by their 105 mm gun tanks). The M103, developed from the M48 with a new, larger turret to take the 120 mm M58 gun, was, of course, the 120 mm gun tank, this was envisioned not only in the "bunker-busting" role, but to slug it out with the Soviet JS-3 and T-10 heavies. I could get into the M60A2 "Starship" with its unique and troubled 152 gun/missile launcher, but that's an entirely discussion of itself!

[@SpiritOfMontgomery]

Whilst your not wrong, what do you think of Montgomery’s asking for a “universal tank?” I don’t have the actual copy of his memo to I think RAC on hand, but he’s basically wanting something with enough speed to exploit breakthroughs (like cruisers), enough armour to be effective infantry support, and firepower to fight enemy armour and support infantry. The “universal tank” he asks for is literally what becomes Centurion I’d say the MBT and “Universal Tank” concept are really the same thing by a different name. Is there any differentiator between the two really?

[@pincopallo7702]

Centauro, according to the italian army website, is an "autoblindo" (=armored car) used by cavalry units, meant to be a quick platform able to engage the enemy (everything, not just tanks). I did not see wrote anywhere "tank destroier" on any official source

[@neurofiedyamato8763]

Pretty much all modern "wheeled tank destroyers" aren't tank destroyers in function. Mostly fast moving medium weight units for operational and strategic mobility. Or its for infantry support and countering everything BUT tanks. Maybe used for terrain where heavier vehicles aren't suitable.

[@emberfist8347]

@@neurofiedyamato8763 They are tank destroyers as they are intended to be used against tanks as a secondary role to their main infantry support role. This is most clear with the M1128 MGS which was designed so we could finally retire the Sheridan which was designed to fire anti-tank missiles.

[@emilchan5379]

Honestly the term tank destroyer is pretty arbitrary.

[@majungasaurusaaaa]

@@neurofiedyamato8763 They're more like infantry support "assault guns". "Tank destroyer" is something I'd call an ATGM carrier.

[@ulissedazante5748]

Tank destroyer appeared in some press release "Centauro tank destroyers deployed for exercises in Latvia" Note that it's a Cavalry Vehicle. No infantry support as no infantry there - few dismounted alongside in Puma, the personnel carrier version of Centauro.

[@54032Zepol]

I was hoping for future heavy tanks in world War three like double barreled turrets or bunker attachments but instead all I got was lousy pick up trucks with giant machine guns on the back.

[@sevenproxies4255]

My personal dream would be a tank armed with a Vulcan rotary cannon as the main weapon. And I've always wondered if someone ever tried it out. Think of an A-10 Warthog, only it's a tank rather than aircraft. While a single round might not be enough to defeat armour on it's own. Bjt what if you had 15 rounds smacking into the same square inch almost at the same time? 🤔

[@Svemirsky]

or at least a huge speaker tower :D

[@wingracer1614]

@@sevenproxies4255 The whole idea of such a weapon on an aircraft is to strike at the thinner top armor. Mounted to a tank, it's going to be aimed at thick and well sloped frontal armor. It's not going to do jack in direct fire against the frontal armor of an M1. Even a lot of AT missile systems (which have MUCH more penetration than a 30mm cannon) have gone to pop up style, hit from above type trajectories. It would be bloody brilliant against light armored vehicles though.

[@sevenproxies4255]

@@wingracer1614 I'm not so sure. Sloped armor does increase the effective thickness of armor plating that is true. But only so much. Would like to do a practical experiment of this

[@wingracer1614]

@@sevenproxies4255 The slope is only part of it. It's also MUCH thicker. Why do you think tanks sport 100mm and up guns? They wouldn't need that if 30mm cannons could do the job. Even 37 and 50mm AT guns have been obsolete since WWII. Those guns in a plane shooting top armor might be effective but not against frontal armor.

[@johnyricco1220]

A MBT is a just tank that had all three elements of armor, mobility and firepower sufficient for the job. Today the technology allows us to this easily but in WWII they couldn’t get it all in one tank. A medium tank has the mobility but not the most powerful gun you have. A heavy tank is required, it’s less mobile so armies had to use both. This came to an end at about 1960. This is when NATO had the 105mm and the Soviets introduced the 115mm. These guns had similar penetration to the Conqueror’s 120mm and T-10’s 122mm, yet they were small enough to fit a medium tank. This made heavy tanks obsolete. Medium tank plus new generation guns = MBT. Modern MBTs are as heavy or heavier than WWII heavy tanks. But their weight is not what defines their role. It’s the fact that there’s no need to put an even bigger gun on a heavier vehicle. Arguably the Chieftain was the last heavy tank, at least in the role it played complementing other NATO tanks like the M60 and Leopard. Today if something bigger than a 120mm or 125mm is required we just use missiles or JDAMs. That is why heavy tanks no longer exist.

[@neurofiedyamato8763]

Certainly that's the most common explanation. But one can imagine that this balanced distribution can easily just be swayed in favor of firepower and armor over mobility and operational requirements. If we use all the same technology but just slap a bigger gun and way thicker armor, then all of a sudden other MBTs can't kill it... but it can kill the MBT. And so the other side would need a MBT. Paveways or JDAMs isn't relevant since they aren't a tank and don't do what a tank does. But of course we then ask, do we need such a tank that can definitely kill all other tanks but no longer fulfill other battlefield tasks? The answer is... No ofc. If we are strictly talking about tank killers, we have other means of doing it hence why tank destroyers have also disappeared. Heavy tanks however were relevant because they fulfilled yet another purpose, breakthrough fortified defenses. Large fortified structures aren't really much of a thing anymore, so there's no job for the heavy tank to fulfill. And normal MBTs can breakthrough any modern fortifications people can come up with.

[@PaulVerhoeven2]

It's just a heavy tank with more modern (and thus more powerful) engine. All this "MBT" BS is just marketing.

[@gamingwhatwecan]

How can all MBTs have sufficient firepower and sufficient armor? If MBTs on one side have firepower sufficient for the job, then MBTs on the other side do not have armor sufficient for the job. The whole point of MBT armor is to stop enemy weapons, mainly MBT weapons. If the gun can penetrate the armor then the armor is insufficient, if not then the gun is insufficient.

[@grahamstrouse1165]

The most massive modern MBT (Abrams, Merkava IV) are actually a bit lighter than the heaviest WWII heavy tanks. Anything that you plan on using in, say, Asia, is likely going to be lighter. Russian, Chinese, Japanese & Korean tanks are all notably lighter than American & Western European tanks.

[@selfdo]

Considering that we've seen "MBTs" ranging in weight from about 40 to 75 tons, trying to class them according to weight is academic and doesn't necessarily reflect their intended role. Tanks, during WWII, became bigger, had bigger guns and more powerful engines, thicker armor, and so on, which, of course, made them considerable more expensive. Never mind that as the war went on and better tanks were developed and deployed, that didn't mean a warring power just simply scrapped the previous line. This was especially seen with the Panzerwaffe, which, due to the Treaty of Versailles, was a late comer to the tank game. The Panzer I was developed in secret in both the Soviet Union and Sweden to circumvent Allied inspectors, it debuted in 1932 with the Reichsheer. It was intended solely as a training vehicle, but its future use as various support vehicles (command tank, self-propelled gun, anti-tank gun, ammo carrier) had already been envisioned. When the Nazi regime, already having authorized the Panzer III and IV, realized they wouldn't be ready soon enough, so what was essentially a larger version of the original Panzer, the Panzer II, was authorized in 1934. Again, it was intended as a training vehicle, though it served as a battle tank all the way into 1944, the last two years being essentially a recon role. Far more variants that had artillery pieces or anti-tank guns, effective throughout the war were produced The same was done with the Panzer III, which did serve as essentially the "main battle tank" well into 1943, the self-propelled gun developed from it by 1940 also served very well as a panzerjager, racking up an estimated 11K kills, more than any other German AFV! The same was also done with the Panzer 38(t), which had been developed by Czechoslovakia and was quite effective during the first few years of the war. Once larger, better armed and armored AFVs, especially T-34s, took on the Panzers, it was outdated and couldn't be upgraded to even take the Panzer IIIs turret and 5 cm gun. But it did serve well as an SP gun (Bison), and PanzerJager (Marder III), and was developed into the famous Hetzer, which fit more with the Inspector-General of the Panzerwaffe, Heinz Guderian, idea of a tank destroyer. The Marder III further emphasized the forced resourcefulness of German AFV development, taking a Czech chassis and engine, and mounting a Soviet-made gun on it! The trouble with all these AFVs was that it was, as the narrator for the UK ITV series "The World at War" noted, "too many types of tanks, too FEW tanks in all. Too many calibers of guns...". This obviously posed a logistical nightmare for the Panzerwaffe. In 1944, Albert Speer proposed to realign AFV production on basic types, using common assembles and parts wherever feasible, in their "Entwicklung" series, but this still had at least FOUR different general categories. Whereas the USA and the Soviet Union stuck to a basic medium tank, and adapted the respective models for other roles. WWII was a war of PRODUCTION, one that Germany lost badly and really had no chance to win anyway.

[@cwjian90]

The first Soviet tank to officially get the name "main battle tank" (osnovnoy boevoy tank) was the T-64B in 1976. Even the T-64A and T-64 were officially called "medium tanks" (sredniy tank) in their acceptance for service documents and manuals. To my knowledge the only US tank to have ever carried the name "main battle tank" was the M60, albeit only briefly.

[@christosacholos1082]

I think also the M48

[@phunkracy]

I think this distinction was viable because for quite a long time there were heavy tanks still in line: M103 and T-10.

[@ivanmonahhov2314]

T-64A is first основной боевой танк last medium was T-64 , MBT combines firepower and armor of heavy tank with mobility of medium tank by soviet designation. Firepower also means gun above 120mm

[@ivanmonahhov2314]

theoretically first soviet MBT is T-44-122 but it was created of MBT was created

[@cwjian90]

@@ivanmonahhov2314 if you look in the TO manual for Object 434 (T-64A) from 1973, it explicitly lists it's type as a "medium" (sredniy) tank. Only after around 1976 was the classification of the T-64A changed to OBT after the T-80 and T-64B entered service.

[@norbertblackrain2379]

I think this general discussion is trying to apply laser cut sharp definition fit for lawyers and more fussy real world application. I like the Chieftains focus on "what can the thing do?" is the most reasonable approach.

[@nepete7]

Similar to the battleship/battle cruiser up to WWI. Once fast battleships became as fast as the battle cruiser, the need for the latter ended. Unfortunately because warships are so expensive, the battle cruisers continued in service (and suffered when placed in line with battleships).

[@LoisoPondohva]

@@aestheticdecision1878 not really show of force, just used. Battleships were (and are) still great at shore bombardment. Gulf War has shown that a battleship with modern fire control system can lay as accurate fires as a cruise missile strike, albeit at somewhat lower ranges, but for a fraction of a cost. Battleships weren't discontinued because they weren't useful, in US Navy specifically they were retired for doctrinal reasons (simplifying, outranged by planes, so seen as a cheaper, but inferior analog for a carrier). In other navies it's almost always cost. A battleship with a modern AA system + escorts wouldn't be as vulnerable as people often think, but modernizing, building and maintaining them would be incredibly expensive, but not as versatile as carriers. But, of course, we should keep in mind that most navies didn't REPLACE battleships with carriers, because most navies don't have either.

[@LoisoPondohva]

@@aestheticdecision1878 maybe, especially against a peer adversary. An interesting consideration is that unlike modern US (and most others) ships, an Iowa armour is practically impervious to 90+% of today's anti ship missiles. Well, that is mainly BECAUSE there are no heavily armoured ships around, so most missiles just aren't developed with them in mind. Surely they would catch up fast if armour was to make a comeback. And although using BBs as artillery platforms against an enemy with no anti ship capability to drastically reduce costs of precision fires is probably behind us no matter if it could make sense, I personally think protected arsenal ships somewhat analogous to BBs, but mainly equipped with huge amounts of missiles/railguns/some future technology just might make a comeback. Because operating air wings in some contested spaces might just be infeasible, even if most of them are drones.

[@classifiedad1]

@@LoisoPondohva It does depend on the anti-ship missile in question, as anti-ship missiles come in various sizes for various targets and situations, from small Hellfire missiles intended for use against small boats to weapons with very large warheads like the P-700 Granit, P-500 Basalt, P-800 Oniks, and BrahMos, meant to destroy much larger supercarriers. We can’t forget submarines too, vessels capable of delivering very powerful weapons that can cripple a battleship in but a few hits. Modern torpedoes are pretty scary, detonating under the keel and sending them to the seabed. Submarines can also carry dozens of cruise missiles and anti-ship missiles just in case the target is too far for torpedoes. As the arbiter of the seas, the submarine is king.

[@LoisoPondohva]

@@classifiedad1 that just goes back to the concession I had already made about peer adversaries. Sure, China or Russia has very capable submarines. Some smaller adversaries have less capable, but still dangerous ones. But for every China there are three Afghanistans, Syrias and Libyas, that operate no submarines and no huge precise missiles. For a cost of one F-35 sortie and 4 precision bombs or 4 tomahawks against such adversaries a battleship or an arsenal ship can lay hundreds of dumb shells on the same target with equivalent precision. A submarine is 100% the most dangerous naval combatant, but there are roles it can't cover. I never argued BBs could better fill the same hunter-killer capability as submarines do, but using submarines for shore operations via internally carried cruise or ballistic missiles is probably as costly, but certainly far more limiting as using 5-th gen flights from a carrier.

[@classifiedad1]

@@LoisoPondohva There are other costs involved with a battleship as well, such as the maintenance, training, and manning, such that it probably would come close to a carrier. A navy with the option to choose between a carrier and a battleship will have to pick what gives the best bang for buck. And the carrier is a far, far, more capable asset against both peer and non-peer adversaries, as its aircraft in a low-intensity fight can not only deliver strikes, but also provide important surveillance and logistical capabilities with its helicopters and maybe even light transports, and be able to employ them better due to its optimization toward flight operations. By contrast, a battleship is limited to firing on shore and coastal targets, and even then terrain can conspire against a battleship if the mountains literally block the flight path of shells hitting certain areas. The ability to conduct aerial surveillance and possibly perform aerial insertion and resupply to friendly forces would be far more limited as such a vessel necessarily would be limited to a smaller number of helicopters or some VTOL aircraft like a V-22. In this context, everything a battleship can do, a carrier can do better, and the carrier will be infinitely more useful in a peer conflict which we really hope will never happen.

[@lookythat2]

In the 80s MBTs were defined in the professional Western literature as having at least a 90mm main gun. If that's valid, then the whole generation of post-WW2 tanks with 88-90 mm guns were early MBTs. The M-26 Pershing and M-46 Pattons (and later Patton tanks) would be included. The Centurion with the 20-pdr (84mmj) and T-54 with a 100mm as well.

[@PrinceKael14]

I've seen the M46 (which is basically just Production Pershing) be considered the first American MBT in most lists.

[@MostlyPennyCat]

You can also see that as classing classing a tank type by what it can kill. And I suspect those numbers conform to, 'everything it was going to go up against' Like the German 88s, the British 17-pndr and the American hv 70mm. There wasn't anything they couldn't kill (at the correct range but it has to be a useful range for fighting those opponents) I think MBT also means Single Class Fleet though. It has to obsolete the idea of the medium and heavy split fleet. So Centurion, T-54 and M47 onwards, the universal tanks.

[@emberfist8347]

First Generation MBTs is the post-war designs up to the end of the 1950s.

[@rogerpennel1798]

Heavy tanks were not initially designed for tank vs tank warfare. They were infantry support tanks designed to assault fortified positions and their armor was all around and not limited to the front quarter. The T-28, T-35, Churchill, KV-1, and KV-2 were designed with this role in mind. The IS series of tanks were based on the KV chassis and they were a reaction to the Panther and Tiger tanks. Assault guns took over the role of breaking fortified lines to create penetrations while the IS series tanks were designed to counter German Panther and Tiger tanks. The role of the IS tanks, Conqueror, and M103 was to act as fire support for medium tanks. The medium tank was the maneuver element that would exploit breakthroughs. In the 1950s all of the combatants came to the realization that heavy tanks were a dead end because their armor wasn't sufficient to resist high velocity 100-105 mm guns firing sabot rounds or rockets and missiles with HEAT warheads. In response, the French and Germans thought armor was ineffective so they designed the AMX-30 and Leopard I with limited armor. So where was the value of a heavy tank with poor mobility and poor mechanical reliability to provide long-range fire support for medium tanks? Because the idea that you had to tether medium tanks to heavy tanks and go slow to receive fire support from heavy tanks was negating any advantages the medium tanks have in mobility in the exploitation phase.

[@selfdo]

When the "medium" tanks have firepower, if not armor, comparable to the "heavies", what's the point of the latter with their higher per unit cost and lesser mobility and reliability?

[@creatorsfreedom6734]

@@selfdo well a tank is not supposed too be a one man army let alone a Super Heavy with out air support or the means to counter

[@quakethedoombringer]

Funny enough, the proliferation of man-portable ATGM basically reverses the "zero armor" doctrine of the Leo1 and AMX30. Their successor, Leo2 (especially from A6 model and above) and the Leclerc, have decent armor compared to their peers

[@thearisen7301]

In US use you could argue Sherman was an MBT because it filled every role a tank would outside those of light tanks. Any role you might see another country use a heavy tank, the US used the Sherman with very few exceptions. TDs were defensive in doctrine with only a handful of E2 assault tanks in just one theater.

[@Uncle_Smallett]

M4 Shermans did not serve role of heavy tank, as a tank to assault fortified positions with significant anti-tank defences like 75+ AT guns and defeating concrete fortified fire positions. They were used in this role, but suffered heavy losses comparing to heavy tanks like Tiger or IS-2.

[@kane357lynch]

​@Uncle_Smallett the sherman jumbo did.

[@Millermacs]

​@@kane357lyncheven in this video at the end, cheiftain specifically describes why the Jumbo was NOT a "Heavy tank" because it only had the 75mm.

[@Napalmratte]

the compresion resulting in the introduction of HEAT FS at too low battle ratings ... oh wrong vid 0.0 I am gonna enjoy that vid with those 2 chatting!

[@piotrmalewski8178]

Oh yeah, that's exactly the problem in War Thunder. For reasons unknown, they basically put 1940s heavy tanks in the same BR as 1970s MBTs and 1980s light vehicles, which means a damn car easily kills a heavy tank before heavy tank can even rotate the turret.

[@ulissedazante5748]

The Centauro in Italy is a Cavalry Vehicle. The doctrine is good old horse cav: Recon, screen, flank security. Centauro could be a tank destroyer, but not its mission.

[@aaronleverton4221]

Charge the enemy's centre?

[@ulissedazante5748]

@@aaronleverton4221 well, last horse cavalry charge was in Russia - Italians stompin' and galoppin', bulges blarin', swords swingin', pistols firin' and the russkies run for their lives. So, in theory... But usually italian cav on Centauro tend to be a lil'more... Sneaky.

[@aaronleverton4221]

@@ulissedazante5748 Polish cavalry, actually, in 1945, but I'll give you the benefit of national pride as my answer would be "Light Horse, Beersheba, 1917" and they did charge the enemy's centre (but, weren't cavalry).

[@alancranford3398]

Video suggestion: why light tanks failed. The late Ian Hogg wrote that there were two types of light tanks--those that were very good during peacetime but failed in war, and light tanks that didn't succeed during peacetime either. Start with the design intent for light tanks. My background included battlefield intelligence analysis as a soldier in the US Army and there were light tanks, tank destroyers, assault guns, medium tanks, heavy tanks and Main Battle Tanks. Going back to World War One the armored car was a protected and mobile machine gun carrier, great for overrunning enemy troops in flat terrain--until they dug in and erected battlefield obstacles. Self-propelled artillery to deal with field fortifications required armor plating enough to survive rifle and machine gun fire (and near miss artillery shells) and the ability to cross trenches and crush wire--the tank was born. Just "tank:" and the name for these Land Battleships (a Royal Navy innovation, just thank Saint Winston) was supposed to disguise them. The light tank came about because heavy tanks were big, expensive, slow, and hard to maneuver. Whippets and the FT-17 weren't really all that much faster but were far less expensive, could carry either a machine gun or, in the case of the FT-17 a light cannon for dealing with enemy machine gun bunkers, and could go places that the regular tank couldn't go. I think that there was one tank-on-tank incident (too small to be called a battle) during the Great War. Tanks such as the Vz38 and the US M2 were initially "tanks" until overcome by events. Two very successful light tanks were the US M24 and the US M41. The USSR put out its PT-76 amphibious tank. Britain's Scorpion was another successful light tank. Why light tanks at all today? As for heavy tanks--evolution of engines, transmissions, suspensions, track technologies and driver controls make the modern Main Battle Tank (TM) as agile as a light tank, as well armored as a heavy tank, with the heavy tank's big gun, and as numerous as medium tanks. Now if these MBTs can be carried in mass quantities by existing aircraft and boats to where they're needed, if bridges and roads won't collapse when the MBT rolls over them, when the MBT's price drops so that they're cheaper than a jeep, and something can be done about fuel consumption and high maintenance requirements...

[@augustuslunasol10thapostle]

I think changing it to “why old light tanks failed” as modern light tanks are just ww2 mediums in weight

[@imrekalman9044]

Sometimes you need good enough firepower with as low weight as possible, for example for ease of transportation, airborne units mainly, or just general mobility. A 10-20 ton vehicle might be able to navigate terrain that a 50-70 ton monster cannot. And there's as always the price tag. The 2S25 comes to mind, a BMD-3 IFV with a 125 mm smoothbore. Though it is classified as self propelled artillery piece (from the GRAU index 2S25, 2 - artillery, S - self propelled), by all intended purposes it is an amphibious light tank.

[@quakethedoombringer]

I think the question would be why pre-cold war light tank failed. If you classify light tanks as something

[@alancranford3398]

@@quakethedoombringer That 30-ton limit would have made the Sherman a "light tank." The M24 light tank was a credible little monster but would have been classified as a heavy tank in 1940. Time changes everything.

[@LHoner-uw1jm]

I think the clue is in the name. A Main Battle Tank is the tank with which you wish to fill your armoured divisions, i.e. the tank you will be fielding the largest numbers of. If you had to define technical specifications for the MBT, they could be reduced to: -should have a chance to survive against most threats -should be able to effectively engage all (landborne)threats But these specs are only there out of necessity, because the majority of your tank force is going to be made up out of that tank. So if it doesn't fulfill these you are in deep shit. I think a technical definiton isn't necessary, because it seems to me, as if the term MBT is a negation of the earlier efforts to sort tanks into light, medium, heavy and whateverthefuck along technical specs like armour thickness or guncaliber. After all, no one is going to argue that the Leopard 1 wasn't a MBT, even though it has almost no armour. The Leopard 1 is a MBT because it was the tank, which from a doctrinal standpoint was capable of filling up west germanys tank divisions and the main tank germany would go to battle with. Basically it is a term of convenience and not something with which to categorize tanks. On top of that the term isn't even exclusionary, so there can be several MBTs with wildly different specs in one army, as long as they can fulfill the same role. So by that logic the first MBTs were the Mark tanks by the british in WW1. :p

[@DeltaEchoGolf]

I think a MBT is just a heavy tank with better mobility. Early heavy tanks were not known for being fast. Once better, more powerful engines were developed, the heavies achieved all three requirements of protection, firepower and mobility. Being able to perform like the old medium tanks while being almost, if not as heavy as the old heavy tanks. Up until the 60's or 70's they were called medium tanks!

[@majungasaurusaaaa]

@@DeltaEchoGolf I wouldn't call an AMX-30 "heavy".

[@Appletank8]

The Leopard 1 started off barely armored enough to stop 75mm guns because composite armor to stop HEAT weapons didn't exist yet.

[@user-do5zk6jh1k]

I agree with your definition. MBT sounds like a procurement program name more than a class of vehicle. That's why there's so much variation in MBT characteristics. Are the M1 and Merkava examples of modern heavy tanks, or are they as much an MBT as the Strv 103 and T-72? It's just a fielding term in an era where variety is not supportable.

[@augustuslunasol10thapostle]

@@majungasaurusaaaa we don’t talk about the AMX

[@slimj091]

Don't forget the Leopard 1. Many would consider it a MBT, but it had paper thin armor.

[@CatoRenasci]

The first tank I recall being designated as a “main battle tank” (but obviously the term was around before that) was the MBT70 - a joint US-German project that died.

[@selfdo]

But it didn't really "die"...lessons learned from it were used by the FRG to build the Leopard II, while we built the Abrams.

[@emberfist8347]

@@selfdo It still had not all the features like the 20mm cannon and the ability to shoot missiles.

[@selfdo]

@@emberfist8347 I think that 40 years ago the 20 mm cannon was considered overkill as a weapon against infantry and/or soft targets...the British had used a 20 mm Poston cannon with their Centurion at one time. As for fending off anti-tank missiles, that capability was beyond what on-board computers could be devised in the 80s to make it work.

[@emberfist8347]

@@selfdo It wasn't meant for infantry but for anti-aircraft use.

[@Nikowalker007]

It didn’t die it was prototype for Leopard 2 and Abrams m1a1

[@micumatrix]

In the end the Sherman was the true MBT, since US build stronger only at the end of the war. Nonetheless a Sherman could destroy a Tiger 1 or Panther. For the germans the Pz 4 was the MBT till encountering T34 and KV1. Than they improved it by introducing slope armour -> Panther. Canon was for both 75mm.

[@CharChar2121]

Do not think of a tank's capability relative to its modern counterparts; think of it in absolutes. The MBT has firepower of the biggest tanks of WWII. It also has protection similar to the heaviest tanks. It is also faster than everything that wasn't an M-18 or on wheels.

[@chefchaudard3580]

You may be right for moden tanks, which cannot be heavier than they are, but how do you fit AMX 30 and Léopard 1 in your classification with their paper thin armor?

[@emberfist8347]

@@chefchaudard3580 They are second generation MBTs. Since the development of anti-tank missiles meant you couldn’t rely on any level armor for protection they put on the amount needed to protect against small arms.

[@SD78]

ATGWs and large calibre APFSDS rounds meant that it wasn't feasible for traditional heavy armour to defeat enemy direct fire without greatly compromising the tank's overall performance.

[@JimWarford1]

Great video and discussion guys! By the way, my favorite, the SU-122-54 assault gun/tank destroyer was the most powerful Soviet armored vehicle fielded before the arrival of the Soviet MBT. While the T-10M heavy tank had a slightly more powerful main gun, the SU-122-54 had two loaders with more space to do their job, which meant a higher rate of fire; and the SU-122-54 had a steroscopic rangefinder which meant more accurate long range fire. Had the anti-gun/pro-missile mafia not killed it, it woiuld have been a big problem for NATO armor.

[@Postoronniy]

Turretless SPGs are much harder to use effectively in the attack than tanks, since to engage the target you not only need to stop, but also orient the entire vehicle towards it. It poorly suited the preferred tactical employment of the Soviet Army Ground Forces.

[@taigh456best8]

for me an MBT is a tank that has the reconnaissance capabilities that a light tank has and its speed and maneuverability, the ability to withstand most enemy attacks of a medium tank and equipped with a heavy gun of heavy tanks. Obviously this is speaking from a World War II point of view on how the various types of tanks were divided into tasks, the light ones for reconnaissance, the medium ones for carrying out support activities and also attacks on other tanks and the heavy ones for using heavy weapons to eliminate every other tank and resist numerous of these. In practice an MBT is the union of all these unique characteristics for each type of tank. For me a sort of first MBT is the Sherman tank because depending on how it was equipped it could perform an enormous variety of roles, of course it had to be modified before arriving on the battlefield, but it had the possibility of covering every role always using the same chassis

[@brianwindsor6565]

The British tank design philosophy of the early 40s came to the requirement to design a 'universal tank' that combined the qualities of the infantry tank and the cruiser tank. The term 'main tank' was also used at the same time. The centurion was the first universal tank that fulfilled these requirement, which would also have been a main tank, but who knows when 'battle' was added to main tank to make it an MBT! Great video. Brian Windsor (Bedfordsire, UK)

[@carlpolen7437]

Umm... did you miss what was said in the video. If there is to be a 'first' MBT it was the German panther... which was before the Brit Centurian. I'm sorry, but you Brits really need to address how much of your governments WW2 propaganda you still believe. I've seen dozens of WW2/Brit KZbinrs - LindyBeige, Caliban, Mark Felton just regurgitate info/propaganda from UK WW2 govenermental Ministry of Information/Propaganda sources withhout even a tiny bit of research into if any of it was actually true. Sorry, maybe the Centurian was the first 'British' tank to fulfull these requirements. It wasn't the 'first'.

[@Syndr1]

Awesome, its my favorite Dynamic Duo. Thanks for the awesome video.

The German Tank expert Rolf Hilmes said that the Heav Tanks disappeared because their overwatch job was taken over by missile armed vehicles . Nice Video :)

[@creatorsfreedom6734]

Nuclear Engine Super Heavy Tanks

[@TigerBaron]

As far as I know the Tiger was called a "Durchbruchwagen" (Breakthrough vehicle in English) in the 30s during it's conceptualization, never saw it being called a medium tank although it's weight fell in that category for the late war period but not the early one because their heaviest tank, being the Panzer IV, was less than 30 tons as far as I remember. As far as the Panther goes, I also consider it the first MBT, although unofficially, because it combined the speed and mobility of the medium tank with the armor and armament (penetration wise if not caliber wise) of the heavy tank. The Centurion evolved from that concept that the British took from the Germans, at least in my eyes, because if you look at British tank design during the war they're obviously behind the curve in that department thinking in the beginning of the war that it's going to be another trench warfare style escapade. It's still quite interesting to think about it however, both the Tiger and King Tiger had the same weight as modern Main Battle Tanks, while they were produced in the 40s with that available technology at the time even with all of their faults they still worked and performed extremely well for their cost in terms of kill to death ratio with many being disabled instead of outright destroyed like a lot of medium tanks such as the T34. Kursk is a prime example of how a few hundred Tigers faced thousands of T34s and still came out on top even though they were on the attack, out numbered and going into minefields but there was also the fact of their crew training and experience, not just the machines themselves.

[@PAcifisti]

Your numbers are a bit skewed. It wasn't a "few hundred" tanks facing off thousand of T-34's, it was thousands of German tanks& assault guns vs thousands USSR tanks. While the soviets had more tanks, we're talking ~2900-3300 vs 5000-7300 depending on the time of the battle. You can't forget that the panzer IV and Stug III were the main workhorses of the German army and did most of the heavy lifting. The shiny tigers and panthers just tend to steal the spotlight. Incidentally, most of the heavy german tigers, panthers and ferdinants got taken out by mines as they tried to advance into minefields. While recoverable, they were a nightmare to attempt to do so, especially under fire. It's true that the Soviet tanks around this time lacked the proper guns to punch through panther and tiger front plates, they were still vulnerable to rear and side (especially the panthers) shots. This meant that the new heavier tanks spearheaded the assaults and the flanks got covered by the numerous Panzers. Otherwise they would've just been flanked and encircled on the spot. Because a few hundred tigers and panthers can't kill nor fight thousands of T-34's.

[@trappenweisseguy27]

Supposedly, you can’t go further than 60 kilometres in Europe without having to cross a river. Bridges have a hard time with vehicles over about 40 tons, some much less than that. So, there was always going to be an upper limit in terms of weight.

[@selfdo]

Poor assumption that they'd be in place anyway. So BRING one with you...hence the M60 and M114 or M1074 AVLBs.

[@news_internationale2035]

The Russian Military despite having so many snorkeling tanks does seem to be opting for bridge building in the Ukraine War.

[@Atomio]

A small idea, I would like to contribute to the discussion (let's call it "short-term tank evolution"): Maybe the heavy tank only evolves out of a longer war, involving great powers and tank friendly landscapes, where the war is waged. Yes, a heavy tank is very resource intensive and expensive to maintain, although there might be another reason. It could become obsolete after only a very short time, because counter weapons will be built soon. And a heavy tank for breaking through enemy lines / fortifications must have good enough armor, that can sustain the hits, otherwise a lighter vehicle could do the same. A heavy tank, that gets destroyed by one mediocre, but good enough hit, just like a medium tank, is pretty much less cost effective compared to its lighter counter-part. It probably has an even larger silouette, gets stuck with expensive recovery, has higher consumptions and so on. Also, its gun is only good, if it is capable of destroying the palette of usually encountered enemy tanks at a reasonable range. If not, chance of fullfilling the purpose of a heavy tank is reduced. In large scale wars, we have seen fast developement and thereby weapon systems evolving at very high speeds, though. A heavy tank that was good for one or two years, seemed promising enough. And where a heavy tank always makes sacrifices is mobility and availability, in favor of firepower and armour. So, if you have a medium tank with a good gun at peace time, that is way more practical and versatile and you are still able to destroy any enemy tank with it at proper ranges, the felt demand for a heavy tank may just be too low to put one into service. Of course, there are other arguments: In the early cold war, the heavy tanks also became obsolete very quickly due to the large scale introduction of HEAT-warheads, which were pretty much able to destroy every tank for a period of time. Then, there are logistical problems of course, like bridges, trains or other transport and so on. During war time, one might want to cope with these restrictions, just for the advantages it will provide in certain situations, id est breakthrough or large tank battles, etc. But this may be out of question at peace. Also the potential use of nuclear weapons had an influence, which might have favored the more mobile main battle tank. Yes, there have always been weapons, which could be used to destroy heavy tanks. There always have been. But reducing this amount of weapons, able to destroy a tank, by adding protection, still is a thing. Nowadays, not just with passive armor, but also with active systems. And yes, there have been heavy tanks, which did not evolve out of a war, but were built at peace time, like the Char B1. But these tanks, even if capable, compared to nowadays, were used with different doctrine in mind.

[@ycplum7062]

Sometime a classification is based on firepower/armor, other times, it is based on mission. I always considered a MBT as the primary multi mission tank.

[@robbabcock_]

I'm glad that we've entered into the age of heavyweight KZbin crossovers! Great video.

[@matthewspencer5086]

The term "Main Battle Tank" was in use when my late Uncle was in the Royal Armoured Corps in the mid-fifties. Because he'd been to the Royal Agricultural College he was asked to be "commander" in a crew test-driving one of the first Conquerors, but I cannot image that the _Conqueror_ was what the term was applied to! There was a massive snowfall on the North York Moors and Dales and the government wanted troops to use "their main battle tanks" to deliver fuel and fodder to the farmers. This would have been a fairly deranged plan with Cromwells or Centurions (narrow roads, drystone walls) but with Conquerors it would have been unimaginable carnage: they would have flattened more sheep than they rescued! {The test Conqueror had an early explosion-suppression system (not unlike some (most?) D-class Motor Gun/Torpedo Boats) and the surviving tank crew members were, in the late 1990s, paid compensation for the long-term health problems caused by methyl bromide poisoning when there was an actual fire (not planned in any way) and this went off. At about the same time that the MoD finally admitted liability for this, all MoD stocks of methyl bromide fire-suppressant were concentrated at RAF Cardington near Bedford for disposal and I saw stacks and stacks of cylinders, cannisters and larger tanks next to the airfield's former hydrogen gas plant from the 182 bus at it went past. Yes, methyl bromide suppresses fires, but it was also used to fumigate newly-arrived ships' cargoes that might harbour insect or rodent pests because it also suppresses pretty well all animal life. What are the Chieftain's views on the things governments do to their own soldiers? And RAF Cardington is not exactly situated in a low-population area either.}

[@TheGrenadier97]

Great discussion. Several "specialized" weapons in the past had this distinct phase that was blurred by battlefield realities and forced into convergent evolutions. In the Great War there were battleships and battlecruisers, essentially replaced by the unofficial "fast battleship" in the 1920s; in the II World War aircraft carriers had three types of planes at least, while few decades later one larger jet displaced them. And of course, one cannot mention tanks without mentioning cavalry: for centuries there was that distinction between heavy and light with dragoons in between, all of which mixed into an "universal" cavalryman by the 1850s. The case of the iconic Centurion tank proves that pre-war doctrine (e.g. cruiser or infantry tanks) was so relatively obsolete that equipment itself got beyond the concept, into a type that could really .

[@Impovsky]

I thought that a Main Battle Tank concept came up from the fact that modern armies adopted a single tank design (per army) to simplify production, deployment, logistic and adjusted their operation practices and tasks profiles accordingly.

[@TheDude50447]

The M1A2 SEP V3 is well over 70 tons. Thats a pretty heavy tank :D

[@willw8011]

A DDG 51 Class is about 10,000 tons. The DDG 1000 class is about 15,000 tons. Both would be the same weight of a light and heavy WW2 cruiser.

[@selfdo]

And in 1940, the French Char B1 bis was their "heavy" tank at 28 tons. Compared to their various Renault and Hotchkiss light, two-man tanks (basically bigger, heavier versions of their venerable FT17 vehicle from WWI) at about 8-1/2 tons each, and their "medium" tank, the Somua S-35 (looks like a "baby" Sherman) at 19 tons, it WAS a "heavy". But that wasn't even the biggest "Frog" tank...that dubious honor went to the Char 2C, at 68 tons. I believe only ten of those leviathans were produced, AFAIK, none saw combat.

[@Nikowalker007]

Almost as much as Tiger 2

[@TheDude50447]

@@Nikowalker007 didnt the Video say that the Tiger 2 was 68 Tons?

[@Nikowalker007]

@@TheDude50447 yep

[@benjammin3381]

the way i understood MBT was that it fills the role of the old designations in one tank. So instead of having mediums for this and heavies for that, you now have the same tank for both situations.

[@mattlentzner674]

My definition - which I'm sure I read somewhere - is that an MBT is a tank designed primarily to fight other tanks. Panther fits that description. Size wise they are heavy medium and value the pieces of the triad of mobility, firepower, and protection equally.

[@Boric78]

Very good this. Took far more away than I was expecting. Should have known - let the experts speak.....

[@charlietipton8502]

Great combination of experts.

[@kewlwarez]

With regards to nomenklatuur and the origin of terms like 'main battle tank', it may be interesting also to look into conventional weapons treaties and their terminology, especially the late Cold War ones like the treaty of limitations on conventional weapons in Europe. That one e.g. redefined the tank in such a way that the Centaro also was one.

[@obsidianjane4413]

What did the Brits call the Chieftain? For its day it was one of the heaviest Western "MBTs". There is only a 5 ton difference in weight between an IS-3 and a T-72. Shaped charge HEAT made the "heavy tank" obsolete. There was no practical thickness of RHA armor that could defeat it. So the term, doctrin, and relative heavier mass and focus on the firepower and protection legs of the tank design triangle favored invested declined. Eventually the medium tank grew to heavy tank proportion when armor and automotive technology developed to make them practical.

[@grumpyboomer61]

The first time I can recall hearing the term Main Battle Tank was in reference to the joint US/German MBT-70 program from the mid 1960's. I suppose it could have originated prior to that as a general concept though.

[@JopardBDS]

This does make me think of the pieces Drachinifel done regards battle cruisers, battleships and fast battleships. Eventually the tech (particularly the powerplant but also better metallurgy) allowed ships to be both full battle hardy and as fast as was ever going to be necessary for naval conflict, making the 2 prior categories only relevant due to financial or treaty restrictions

[@frankgulla2335]

Great discussion.

[@adams8530]

That's quite similar to the way i see it. Medium tanks continued to get better weapons and armor schemes, while heavy tanks continued to get better engines and mobility closer to medium tanks, at some point the line has blurred so much they coalesced into MBTs, and now we have both 45 ton and 70 ton tanks classified as MBTs.

[@skipperg4436]

Better question to ask, what would be a heavy tank in modern warfare? Among Abrams, Paladin and Bradley, what kind of a vehicle would qualify as a "heavy tank"?

[@phil20_20]

Well, look how many times they brought back the battleship. Heavily armored weaponry is missed eventually, especially when great powers start running out of fancy ammunition. A heavily armored slugger always comes through. I think reasonable operating speed is a big factor in addition to the durable armor and effective firepower. The main drawback of the heavy tank concept was lack of speed. If it went any faster, they'd add more weight to it. ;D I think the main point of the Main Battletank is optimized armor and firepower, within the parameter of useful battlefield speed. Just like the Fast Battleships, you had to get to the fight first.

[@bernieeod57]

The MBT combines the function of the Heavy & Medium tank plus the Tank destroyer. The Sheridan was the last light tank whose role was superseded by armored wheeled vehicles

[@mikem67]

@militaryhistoryvisualized. The development of the MBT, and the term, was developed in the early 70s. The US and West Germany were developing the MBT-70. This was a "main battle tank" that would replace the in service M48 medium and the "heavier" M60 with a single tank that would fill both roles. Out of this came the M1 Abrams and Leopard 2 tanks.

[@ivankrylov6270]

The t-10 and cheiftan were removed from service after the introduction of lightweight 120+mm tank guns. The difference with caliber now meant that a lightweight and highly mobile platform could sling an HE shell that is destructive enough to take out fortifications in the assault role. That's what made the heavy tank obsolete in doctrine

[@PrinceKael14]

Here's a question I've come up with while trying to build doctrine for fictional states: Why use a tank for recon at all? Why not use exclusively light tracked vehicles or wheeled vehicles that can move much faster and are typically much smaller (and thus easier to hide) than a tank, even a light tank?

[@TheChieftainsHatch]

Some countries do that. Others also give their recon troops a counter reconnaissance role, others want to be able to "fight for information" by punching through the first, light line to see what lies beyond, and the US, at least, considers its recon units to be multi functional and capable of holding their own in a full on fight.

[@TheLDK47]

To the part about the term MBT missing in official documentation. What about the MBT-70 / Kampfpanzer 70? And in general, is the term Kampfpanzer official in the Bundeswehr?

[@1337flite]

MBTs - I think - are tanks where there was far less clear trade off between protection, firepower and mobility. I think the tradeoffs came back a bit (compare Leopard I - low armoured and Chieftain - low mobility) but we kept the terminology anyway, because all though tradeoffs became a bit more prominent they were not as prominent as they had been pre WWII and you can still essentially use the same tank for most roles. Cold war Brit recon units still had tanks - Scorpions. Light tanks, but still tanks.

[@LessAiredvanU]

The resignation for the Scorpion was, Reconnaissance, Armoured, Tracked, making it a companion to the wheeled Armoured Reconnaissance vehicles like Ferret than the tanks such as Centurion or Chieftain.

[@Gho73t]

I think that the western MBT kind of developed after the war when all western forces got access to all the stuff from both sides. Because if you think about it both Panther and Sherman went in the MBT direction but came from different angles. The Sherman came from below basically optimizing the medium tank philosophy of something that could be used on mass and would be suited for all theaters. While the Panther came from above performing something like an ABC analysis for heavy tanks. Because the Panther managed to reach 90% of a heavy tank’s capabilities with just 10% of its cost. So, I would argue that the modern MBT from a western perspective is a combination of the Panther´s competitiveness with the compatibility of the Sherman. Meanwhile the soviets simply scaled up the t-34 which also worked out fine XD

[@whya2ndaccount]

A MBT is effectively a "multi-role" tank (i.e. one vehicle, many roles). No ongoing requirement for a "heavy" (which by the way is not weight dependent). It also simplifies logistic and other support issues.

[@WWFanatic0]

I would contend that the Sherman and to a lesser extent T-34 were at minimum proto-MBTs, like a gen 0.5 MBT. In Sherman's case, it was *the* tank of the US aside from the very early war when production hadn't caught up with expansion of the army and lend-lease (and production lines of the Grant got extend to ensure something got built as retooling takes time) meaning some line units were light tanks and some Grants still in service. It was there to do all the jobs a tank needed to do in breakthrough and exploitation. With the 76mm gun it could kill basically anything on the battlefield aside from some of the true monstrosities like Jagdtiger and even the 75mm was far more capable against tanks than movies and games would have you think. It was well armored with more emphasis on the front with a slope. Aside from recon tanks (which generally has been a light tank role) or theaters where even a Sherman is too heavy it was basically the only tank the US used from 1943 onwards. Compare this to the Germans and Brits who had a dizzying array of tanks in service. You might run into Panzers III-VI in the same battle and that's just the proper tanks not counting TDs, and assault guns. The Brits had too many tanks beginning with C for me to count plus a few that got to use other letters like Matilda and Valentine. A ley part of being an MBT is that it more or less is all you need. For 95% of jobs you need a tank for it can do them 95% of the time as good or better than any other tank. There's niche cases like recon or amphibious operations where a lighter tank might be better, but the universality is a big part of the MBT.

[@ShadowDragon1848]

You could also argue that on the one hand the medium tank evolved to have the same capabilities as former heavy tanks had AND a new version of heavy tanks would be in the range of 90 to 100 tons with maybe a 150 mm gun or so. Sounds impressive, but that would absolutely over the top.

[@franzenders344]

Yes, I agree with many comments saying that the main battle tank is a tank that functions in most roles and fills your armored units and has a balance of firepower, armor and mobility. I did not hear a discussion or mention of the 60's where this balance was upset. Notably, the Germans and French decided that you could not get enough armor to defeat HEAT rounds/missles, so they figured mobility equals armor so the Leopard 1 and AMX-30 are firepower and 2x mobility.

[@jamesevans886]

Something I learnt a long time ago is that Military terms become amazing elastic over time and nothing is set in concrete. The term heavy tank was normally implied a break in and or break through tank. As far as I am aware it is the British coined the term MBT in a limited way concerning a tank which could equally function as both infantry tank and cruiser tank. Montgomery referred to this as a universal main tank in his doctrine for the 21st army group towards the very end of the 2nd World War. The project was politically high jacked by the cruiser faction and the end product was the Centurion MK1 armed with a 17lbs gun. This is the tank the English referred to as the first MBT. The term caught on and NATO countries started to referring to their new designs as MBT. It is an interesting question. Did MBTs exist before there were MTBs. If the answer is yes then we need to look at candidates that combine 2 or more forms into one vehicle. If you decide that it is the Panther that is the first MTB then surely it is trumped by the T-34 which had an effective HE shell, but it isn't the first MTB either. Perhaps it is some of the multi turreted designs prior the WW2. Some of which had low velocity gunned turrets and high velocity turrets. Don't forget we are looking for what best fulfils the definition not how good they actually was as many designs of this time period quickly became obsolete. Other candidates would be the Char B or the M3. Or do we draw a line in the sand and say it applies only to post WW2 designs. Also your perspective changes things as well. From a WW2 perspective all modern MTBs are heavy tanks and from a modern view they are all medium tanks. Take the M24/M46 Patton tank. During WW2 it was classified as a heavy tank while post WW2 it was reclassified as a medium. There will always the ambiguity cased by form and function. Do we classify something by what it was designed to do or by what it was eventually used for. Because the way NATO tanks were used during the Korean war should they be reclassified as armoured artillery? Time and definition of terms do not make good bed fellows. Thanks guys for a very thought provoking video.

[@kevinjohnson8220]

MBTs tend to have a balance of armour protection, mobility, and firepower, while heavy tanks tended to sacrifice mobility for increased armour protection and firepower. The Panther and Pershing were primitive MBTs and the T-54 was developed shortly after these.

[@mikaelgrande6968]

It’s very confusing trying to use the same words across multiple nationalities when every nation have their own interpretation of said word

[@ditzydoo4378]

When it came down to doing all jobs across the whole battle front with a good gun, high mobility, good armor, reliability and maintainability during WWII it was hands down the later 76mm HVSS versions of the Sherman tank. The Panters Achilles heel was always its maneuverability/mobility, reliability and maintainability which always stopped it from being the best all-around tank.

[@majungasaurusaaaa]

The 75mm was the more numerous and versatile in ww2. It was a good enough gun for combatting all medium tanks and a far better gun for infantry support.

[@nickthenoodle9206]

The Sherman was probably the first MBT in practice, if not in theory. It wasn't great at the heavy tank role, not even the Jumbo variant, which was an inferior Infantry Tank compared to the obvious, but the USA did use the M4 successfully in all roles. It was why it was used by all nations that had access to them.

[@phunkracy]

If Sherman was an MBT then why T-34 wouldn't be?

[@nickthenoodle9206]

@@phunkracy Because the KV-1 was being used as a heavy.

[@phunkracy]

@@nickthenoodle9206 Yet T-34 was also used in the same role as KV-1. The entire reason KV-1 was deemed unsuccessful is because it had comparable weaponry and armor to T-34 while being less mobile.

[@nickthenoodle9206]

@@phunkracy While you have a heavy tank being developed and used along side a medium, you don't have an MBT. Some people consider the Centurion to be the first MBT, but while you have the Conqueror heavy tank, that's not the case. Same with Panther and Tigers.

[@boydgrandy5769]

The Panther really is a good candidate for being an MBT. It was fast, relatively light, heavily gunned, and armored sufficiently well to survive hostile fires at its own effective range. It could kill, or at least mission kill, any Allied or Soviet tank it could encounter. It was light enough to be able to transit to the battle over existing bridges if necessary, unlike the slower, heavier, better armored and up-gunned Tigers, while still able to shrug off most Allied anti-tank long range fires. It had drawbacks, mostly centered around an underpowered engine and an unreliable drive train, but it was in most respects the tank that could perform the armor mission assigned better than the other German tank models and marks.

[@Ukraineaissance2014]

I think tanks will go the other way now, they cant get the armour to defeat top attack manpads while being transportable or able to use public infrastructure so they will go for extreme mobility. We will have something like heavier infantry fighting vehicles used to electronically network drones, artillery fire and anti tank fire. Main armaments perhaps a cannon, anti tank rockets as a main anti tank measure and an actually useful AA weapon. The space where you used to carry soldiers used for a better engine and electromic warfare equipment. These will be used alongside some traditional MBTs though

[@HerrPolden]

So, if the definition of a MBT is a tank that has enough protection to take hits, the Leopard 1 and AMX30 would not really qualify, as they do not prioritize prioritize armor? Or are the roles to be filled Infantry tank, cruiser and TD (light or heavy)?

[@onQ11]

A main battle tank is the heaviest tank that will still function reliably. Originally it was described as an intermediate between a medium tank (+- 30 tons) and a heavy tank (45+ tons). However as technology develops the allowed weight keeps increasing. Its that simple.

[@TheIvanNewb]

I remember James Holland's top five tanks video over on the Bovington Tank Museum's YT page, and some people in the comments lost their shit at him calling the Churchill a main battle tank. What he said was that it was a battle tank, and the main one for the British in many cases. I think the same might apply here, that MBT isn't a technical or doctrinal term, but a word for what the standard gun tank of modern armies has developed into? Because one could also argue that the Tiger was used as an MBT, as a maneuvering gun tank shooting at whatever it could as opposed to the breakthrough role of a heavy tank. Just my two cents though, interesting discussion!

[@George_M_]

Heavy tank armor and guns are now on the medium/main tank while retaining high mobility (Russian tank reverse speed notwithstanding). The ability to deliver a good HE shell is everything. The proliferation of effective infantry portable antitank weapons make the extra expense not worth it too.

[@patrickshanley4466]

Great discussion guys, I have to go with the chieftain

[@mikekarns5286]

MBT came out as a term when the Joint US-German MBT-70 was built as a concept was being cobbled together. Because they made a mistake after that failed. In the frustration due to the germans wanting a lighter armored bigger gun tank built for specific mission and the US design that wanted a multi-role tank heavier tank. What happened after the MBT-70 concept failed was the US design team asked real tankers, IE Sheridan M551 tankers. And their input was that they needed a tank that could be more survivable, originally meaning heavier armor than a Sheridan. That was also the time when American forces in central Europe decided to abandon the multiple types of tanks (light and main) and concentrate on a single type of tank. The interim tank was the M60A1 thru M60A3 variants. Instead of the M551's and M113's M60A3's replaced the Sheridans in the squadrons. The trade off was mobility for crew survivability. The Idea was that trained tankers were more valuable than tanks, Nato could replace the vehicles but needed to retain the crews alive and as unhurt as possible. Doctrine changed then also, NATO became interested in the deep interdiction strategy. Armor Cavalry Squadrons were to delay the Russians until the effects of the deep interdiction of the Russian supply of fuel and munitions were disrupted. Much as the same strategy the Ukraine side used. The weak link was not the Russian tanks, it was their Fuel trucks. Destroy them and you blunt the offensive, and then subject the spearheads to relentless attrition. Just as the Germans used tanks in the North african desert, it was the doctrinal use of the assets in combined warfare that gave them the edge. Again in Iraq the Americans learned or relearned the combined tank - infantry team concept that towards the end of WWII was a well practised procedure. A tank - infantry team is a powerful and more flexible unit. In that the tank can protect the infantry from medium and large threats and the infantry part of the team can protect the tank from the smaller deadly weapons. Modern warfare requires more men as replacements so that units are not rapidly depleted to the point that they are combat ineffective. As the lethality reaches the limits on infantry and drone weapons, the ability to replace losses and retain live crews and troops will be a decisive factor in winning.

[@Syndie702]

Doctrine aside, the M4 Sherman was essentially used as a jack of all trades, universal tank. The Americans had no heavy tank for most of the war, and never really missed them.

[@selfdo]

Logistics (not only producing and shipping these 32-ton vehicles from their factories in the Midwest, but also loading them aboard "Liberty" ships, getting across the Atlantic to Europe, and off-loading them via LSTs or, when available, the "Mulberries" or European ports like Cherbourg or Antwerp, dictated the use of the Sherman. The Sherman was fast...ENOUGH. Its protection was...ENOUGH, especially once the "wet stowage" to prevent ammo fires if penetrated was devised. It's firepower was...ENOUGH, and generally suited its intended roles and did well ENOUGH against most German and Japanese AFVs that it took on. And yes, thanks to Yankees and Limey ingenuity (notably with the latter: "Hobart's Funnies"), the Sherman could and was adapted to a variety of roles...ARVs, CEVs, the "tank dozer", having the "prow" to cut through the thick hedges of the "Bocage" in Normandy, and fitted later in the war with either more potent anti-tank main weapons, or, in the infantry support role, a short-barreled 105 mm gun-howtizer. The chassis was adapted, with different turrets and light armor, to maximize vehicle speed and acceleration ("shoot and scoot"), as two different types of M10 tank destroyers, sporting either the 76 mm gun ("Wolverine") or the 90 mm gun ("Jackson" or "Slugger"). Post-War, the IDF did things with Shermans never envisioned, putting into them updated diesel engines and modern fire control systems, as well as more potent main weapons, never mind all the specialized vehicle that IMI or Soltam devised, like the L33 155 mm Howitzer or the "Tankbulance". In the 1967 and 1973 wars, their "Super Shermans" were more than a match for Egyptian, Syrian, and Jordanian armor, though the success in those engagements may, like the US Army prevailing in Korea, especially in the August and September 1950 battles along the Naktong river, can probably be better attributed to leadership, logistics, training, experience, and doctrine than the relative technical merits of the AFVs involved.

[@Syndie702]

​@@selfdo Logistics led the US to develop a universal tank before technical specifications allowed a single AFV platform to excel in all roles sans modification. The M4 Sherman may not excel as a breakthrough tank sans modification, but it was the MAIN armored vehicle used in every BATTLE the US fought in, and was employed in all the roles a TANK might be used. It may have been a medium tank on paper, and in terms of weight and armament but it was America's first Main Battle Tank, and entered service well before the Panther.

[@selfdo]

@@Syndie702The M4 was classified as a "medium" simply because it was intended to be deployed along with the M3/M5 Stuart Light tanks (more recon vehicles), and later the M24 Chaffee, and, at first, the M6 Heavy tank (which, thankfully, was not produced in significant numbers), later the M26 Pershing, which got into action only as the war had but a few months left. True, it was exactly logistical considerations that had the M4 Sherman doing just about EVERYTHING, from infantry fire support, anti-tank work, CEVs, ARVs, and other specialized vehicles. When you have a good automotive platform to begin with, why literally re-invent the wheel? BTW, the Sherman "Jumbo" or "Cobra King", with considerably thickened frontal armor, did quite well in the "break-through" role, able to shrug off 75 mm German anti-tank rounds. This is yet another reason why I think the Sherman had it over the Soviet T-34s and ANY German panzer as the best, certainly most VERSATILE, tank of WWII. Given how the IDF was able to upgrade the Sherman into a battle tank that could take on and prevail over much more modern Soviet-made armor, as well as adapt it into just about anything that 'clanked', including vehicles like the Tankbulance and the Soltam L33 155 mm howitzer, I'd say that's all the evidence of the worth of the basic Sherman design.

[@lavrentivs9891]

Now we need an explanation of "breakthrough tank". Many countries seem to talk about them, but they seem to refer to two different types of tank. Either a heavily armed and armoured tank that will help create a breakthrough in the enemy lines e.g. the Tiger or JS2, or it refers to a fast medium-sized tank with good enough gun, armour and mobility to exploit the breakthrough, e.g. Sherman or Cromwell.

[@TheRezro]

Common definition of MBT is (rationally) Heavy Tanks, with flexibility of Medium Tanks and sometimes speed of Light Tank (optionally). Original tank roles were Infantry Tanks (basically mobile bunkers), Cruiser Tanks (close to modern concept) and Scout Tanks (self explanatory). During WW2 tanks become universal enough that they become defined rather by weight. Heavy, Medium and Light. Though it correlated to original specialty, they also do other things. Finally Centurion was heavy, flexible and fast enough that it become new quality on its own. In modern days Light Tanks are defined as actually Assault Guns (providing fire suport to mechanized units) also capable of limited tank operations (they usually use lighter, but still rather heavy chassis of IFV's).

[@TheRezro]

Panther was in theory MBT, even in practice it was defined as heavy and in reality it was hunk of junk. Lot of people also confuse prototype Panther II, with actual production model (what was so bad it could be killed with anti-tank rifle). Centurion was first MBT what actually reach design maturity.

[@oisnowy5368]

Humans like categories. And like to place things into categories. That makes one able to say this is like that, or this is not like that. It's a mental tool. Says more about us than about light/medium/heavy/main battle tanks.

[@gort8203]

Excellent comment! I also get a kick out of all the arguments that this or that airplane was not a fighter but was an interceptor, or this jet is really just Generation 4.36259 instead of Gen 5. It's all quite silly. An airplane is what it is capable of doing, and most can do more than one thing. Apparently the same thing applies to many armored vehicles. People also argue whether the MG-34 or another weapon was the first "universal machine gun", a single weapon that could replace light and medium machine guns, and maybe even a heavy in some circumstances. I wonder if the designers of the MG-32 and MG-42 were concerned with what category it would fit into, or were just trying to build the best combination of mobility and firepower they could build. If anybody has the answer, I'm curious.

[@majungasaurusaaaa]

@@gort8203 Designers and engineers have limited budgets and doctrinal as well as political pressure to keep in mind. If Hitler told you he wants the MG to be "universal", it better be able to do the trick. So yes, they were absolutely concerned. Their careers depended on it.

[@gort8203]

@@majungasaurusaaaa "IF" Hitler told you . . . Well, obviously. The question is did he, or any other authority, and what did they tell you. The designers are obviously trying to meet performance specifications for any new design. The question is whether it was specified as or thought of in terms of a new category called "universal".

[@Moggy471]

The designation of a tank by the calibre of it's gun makes sense. At sea there wre a lot of light cruisers that were bigger and displaced more than some heavy cruisers. The designation was purely about the guns.

[@stephenbesley3177]

The Egyptians still had a few old IS3 heavies used as pillboxes 1973 but the old heavy tank thing was pretty dead by then

[@Redmanticore]

i think its still a small wonder in technology, that armored personnel carriers of today can have tank-killer guns in them. (like patria amv xp, or centauro II, that can be fitted with 120mm cannon) and still go on water, or drive 100km/h, with 1000kilometer range. so, in a pinch, fast moving infantry units with just apc´s could destroy main battle tanks and out-maneuver them. and probably much cheaper than the 7million abram, with 420 kilometer range, probably 1/7th of the price. so, in theory, you could have seven 120mm units versus 1 abrams, if its 7million vs. 7 million fight. if you have 10 abrams, he has 70 apc tank destroyers. a highly mobile tank-killer groups like that, that can also carry antitank personnel, are perfect for defenders. sudden counter-strike pincer movements, ambushes, and fast, nimble retreats. that's just 35 000kg in weight, 71 000 lb in usa units, 35 tons. m1 abrams that has same 120mm cannon is 67tons.

[@DD-qw4fz]

Heavy tanks (dis)appeared for multiple reasons Doctrinal - many ideas about tanks in the 1920s and 30s were created using theories often influenced by the traditional split between infantry and cavalry, infantry breaches cavalry exploits. As such the idea on the tank were similar, influenced by traditional branches of the military. The heavy tank was there to "grind through". Today we know what works and what not what are limitations of the tank... Technological - both limits and advances in technology spelled the end of the heavy tank. It must be noted that in its core the idea of a heavy tank was to bust through standard AT defences of the time and be heavily armored from all sides. It was after all taking the brunt of enemy fire when enemy positions are at best softened up by artillery and air support. At the time of 1930s and up to 1942 anti tank guns usually were of smaller caliber and had at best mediocre penetration. This enabled for the heavy tank to shine as its overall tonnage could still be held under 60 tonns and the all around armor protection would be such that guns up to that point had real trouble getting through them. In 1943 things started to change more than they did in the last 7 years, large numbers of 17 pounders pak 40s and 43s , Soviet 85 and 100 mil guns meant that the before respectable 80-120 mm of armor on the heavy tank were suddenly not enough for a heavy tank...which led to even thicker armor... and thats where the first cracks in the idea of a heavy tank became apparent with the.... ....Experience of 1943 onwards (and later introduction of primitive ATGMS). Imo it all came down to practical volume versus weight versus armor penetration of AT guns With the King Tiger the Germans refused to sacrifice interna volume and ammo stowage...this led to a tank with a staggering (for that time) weight of 70 tons...and yet the side armor of the King Tiger was marginally better than that of the Tiger 1. The front armor surface is small compared to the side profile of any tank and thats two sides. Adding a inch of armor on the front is a challenge but can be doe and was frequently done (best example is perhaps the panzer4) ...adding a inch to the thickness of the armor surface (of both sides) of the tank is a huge increase in weight for little gain. Long gone were the years of 39-41 where a medium tank was in the 15-20 ton range and heavies were maybe 30-35...at that time there was "space for growth" so to speak. The Russians/Soviets went the opposite direction and created the IS2 and 3, focus was on maximum armor in a sub 50 ton tank, sacrificing internal volume, crew ergonomics and most notably ammo stowage...in the end this didnt fare well , coupled with the 122 gun it had a miserable rof and yet again the armor was still far from making a pak 40 "the second pak36 door knocker" when facing a KV1 in 1941. There was just no place for the heavy tank to grow...and by experience no matter the designations used at the time all sides naturally started making tanks that had the following specs/focus by 1944-45 based on practical experience...some would call it medium, or a cruiser tank, or whatever it really doesnt matter... What we got is the following Firepower close to that of a late war ww2 heavy tank - introduction of large diameter turrets and turret rings Frontal armor similar to that of a heavy tank Mobility close or similar to that of a medium tank at the expense of side armor (for the before mentioned reasons explained) Focus on AP first and HE second while maintaining a at least good ROF (so no huge guns like the 122 on the IS2) Panther, T-44, Centurion, Pershing..all fit the bill with minor variations

[@martinrose2833]

The first MBT called an MBT in 1969 was. The Chieftain MBT was the first tank designed as a MBT , Leopard was a medium tank that became a MBT with Leopard II

[@martinrose2833]

It was made with the intention of replacing both Centurion and Conqueror and called an MBT

[@gerfand]

I look at the Tiger and I would argue that the thing that makes one a Heavy, Medium or Light is how they armour it, Lights have no armour, Mediums have frontal armour, and Heavies have all around armour (even if front is thicker) but that can only work with Germans and by my view. What I like instead is Infantry and Cruiser tanks, because Cruisers are designed for being fast and fight where they need to be, meanwhile Infantry are designed to support the infantry. This means that an Abrams would be a Cruiser, meanwhile something like the new "Light Tank" the US is building could be called a Infantry tank, since they would not be used in a Cruiser like role, but instead as fire support units for the infantry. ofc this is all "tism" just like discussing the difference between Battle cruiser and Battleship after WW1

[@Silver-vy9ie]

What about side armour? should side armour be considered to be the key feature of heavy tank? Since the role of "breakthrough" of "heavy" tank often come across hits from all angles, with example of US m6/m4a3e2, german DWs, which lead to Tigers, British infantry tanks, Russian KVs, ISs, T--10 all had very good side armor compare to medium or early MBTs.

[@acctsys]

This is how technology advances. Breaking through certain constraining variables enables exploration of different combinations.

[@hetzer5926]

I’d actually argue that the first MBT would have been the Sherman. It was the backbone of the US armored forces. They were fast, assisted infantry and could destroy tanks other tanks. Especially the Sherman’s equipped with the longer 76mm.

[@iMost067]

I just there to say that by any qualification if MBT didnt existed as term - Abrams M1 and Leclerc is in fact a Heavy tanks, being much heavier than JS-3, JS-8 and Pershing

[@snugglecity3500]

My thought was that an mbt was an mbt because it was the main battle tank used by a nation. For instance if you have a challenger 2 as the tank you use as an armoured fist but you also have a t72 that you use for ambushing vehicle columns and then you use a leopard 2 as a more mobile tank designed to flank the enemy armour then none arr your main battle tank.

[@hummel6364]

The big thing that makes the Panther the first MBT is it's armament. If not for that, I would say the T-34, and Sherman tanks are good contenders, as they had most of the capabilities the Panther had to some degree. Really I would classify all three of those as proto-MBTs if I was the ultimate authority on the matter. In my opinion the real dividing line is when sabot projectiles (also squash head and modern HEAT to an extend) became prominent, giving any tanks carrying guns capable of firing these projectiles the ability to destroy nearly anything the enemy might throw at them with relative ease, including the likelihood of being able to destroy future enemy vehicles with reasonable effectiveness. For example the Panther could not be expected to destroy a vehicle like the late Soviet heavy tank concepts, or the Maus, although it might be able to under ideal conditions. Such vehicles would have to be taken care of using specialized tactics, possibly relying on artillery support, or infantry getting close enough to fire a HEAT projectile into the side of said tanks. TL;DR: If it can't handle ANY armored target that it might be forced to face, without extensive support, it isn't an MBT in my eyes. This means MBTs were really a post-war development being made in the same time period by most/all major powers. This also means MBTs can lose their status as MBTs over time.

[@daredemontriple6]

Personally, I think MBT is just the point at which tank designs no longer have to compromise on 1 side of the tank triangle to achieve the other 2 sides in sufficient quantity. Tiger I - Heavily armoured, Heavily armed, but the compromise is it's poor mobility. T-34, Heavily armed and highly mobile, but a distinct lack of armour. All the British Cruisers (and IMO the M3/M4s of the States) compromised on both armour and firepower until later in the war, in favour of mobility and importantly mass production. Panther comes close to striking the balance - but it's underpowered for the armour. An excellent gun for tank-hunting but it's actually a little underwhelming for HE work. Panther *can* shift when it wants to, at least in theory, but at 14hp/ton it's rare that it gets there. Compare this with something like Centurion, which actually has a slightly worse power-to-weight ratio at ~13hp/ton, but has stronger frontal armour, and far stronger side and rear armour. Centurion represents the protection of a tank like Tiger I, with the mobility of a tank like Panther, and firepower much better than anything else once the L7 shows up. And at more or less the same time everyone else starts to come to the same conclusion as the Brits. T54/55, Patton, Leopard 1, AMX 30 - All of them have Firepower, Mobility, and protection in sufficient quantity. That does not mean that they were impervious, or they were lightning quick, or that they could kill any target from 8 miles - but it does mean they had no glaring weaknesses like Panther's soft sides and rear or Cromwell's under-powered 6pdr, or KV-1s sluggishness. All of them could be expected to be reasonably mobile, reasonably resilient, and reasonably deadly in a stand-up fight, whereas the wartime armour before them would often need to add caveats to achieve the same, i.e. resilient, so long as it's only attacked from the front.

[@timgerritsen7579]

To me, the MBT is a tank with the maneuverability of a medium tank with the fire power of a heavy tank, which made the distinction of both obsolete. It's a bit like how the 'fast battleship' made the distinction of a battlecruiser (which had the maneuverability of a cruiser and the firepower of a battleship) from a battleship obsolete. Technology made the old definitions no longer valid.

[@Raptor747]

I'd say that the Panther kind of checked all of the boxes of an MBT, but its mechanical/logistical problems prevented it from actually acting like an MBT would. Unable to take proper advantage of its operational mobility because its transmissions/final drives couldn't really handle such movement on an operational scale in any kind of sustainable way. Unable to actually deal with the firepower of practically all threats it could face via its frontal armor because of faulty construction/armor plating and the prevalence of actual heavy tanks and heavy tank destroyers, while also not quite being able to deal with the armor of said vehicles easily either. Its weight was also very high, especially for its engine power and supporting engineering equipment, making it a heavy tank in all but name. But the key characteristics--or the clear potential for them--are there.

[@majungasaurusaaaa]

Too thin side armor. Still too heavy for the infrastructure of the time. It has the drawbacks of a heavy weight wise but not the armor advantage. It was an overweight, heavily frontally armored doctrinal medium.

[@notsofresh8563]

If you want to win a fight you have to both punch but also dodge and weave. I would imagine suspension design had quite a bit to do with the drop in heavy armour. Better suspension=greater speed and mobility. Since the tank could drive and turn faster, rear and side armour could be reduced because it is easier to turn towards enemy and back away fast while shooting. The reduction in armour weight additionally increased mobility. Heavy tanks needed side and rear armour because they were not very nimble and were much more likely to take a side hit as a result.

[@Wick9876]

Soviet tanks can't back away fast. The reverse speed of a T-80 is 10mph while it's 4mph on the T-54 through T-72.

[@captiannemo1587]

The American prospective is interesting. The 90mm cannon is proposed for T1/M6 as well as T14 and eventually M4. As is several studies to up armor all 3.

[@MetalX34]

that said, mbts are pretty big, tough and heavy themselves relatively to other armours. lore aficionados take notes : make sure your fictional country's army doctrine labels their mbts as heavy tanks just to tease everyone without necessarily being nonsensical. would not be surprised some nation already kinda did that irl, there is even another comment claiming soviet t64s were assigned as breakthrough tanks replacing heavy t10s.

[@Jadefox32]

For those not familiar, the MBT concept (a tank with better armored protection than a medium tank, the mobility of a medium tank, and the firepower of a heavy tank) only came about after world War II and in that regard the M47, Centurion Mk 3, and the T-54 started that trend off. The M46 and tanks preceeding it in US service are medium tanks (M26 was redesignated a medium tank after WW2). Similarly, the Centurion Mk 2 and 1 are medium tanks, T-44 is also a medium, and so is the Panther. If we look back on it now, all these tanks fit the concept but can't be called MBTs because it didn't exist as an idea at the time.

[@misosvantner9080]

In other words it's abpout the purpose and not the desigm. Altough purpose to some extend dictated the design, which is why people get confused. Btw, Soviets were designing heavy tanks well after WWII: T-10 (retired only in 90ties)

[@brucetucker4847]

I don't think this really answers the question. "Advances in engine tech mean you can now have the armor and gun of a heavy tank with the mobility of a medium tank" ignores what seems to me to be an obvious corollary: advances in engine technology also mean you can have even _more_ armor and gun, more than anything ever contemplated in WW2 or for a postwar MBT, and still have the mobility of a a heavy tank. Such a tank might be as resistant to the gun of an MBT as a Tiger II was to a WW2 medium tank, and as easily able to penetrate an MBT at long range as a Tiger II was a WW2 medium tank. I would imagine it was more a recognition that the heavy tank concept was flawed from the get-go, and that a tank with as limited mobility as a Tiger II (or the IS-3) was of equally limited usefulness no matter how much its gun and armor outmatched those of medium tanks/MBTs. And also, of course, no matter how much armor you pile on it is still just as vulnerable to other types of casualties - immobilization by mines, for example, or air attack, or engine breakdown - as a much cheaper MBT.

[@noahvcat9855]

I would like to say that from my understanding, the role of a Assault Tank which is to help support infantry to attack enemy positions and provide fire support and all, is somewhat similar to the British doctrine for Infantry Tank where it is meant to support and help punch a hole into enemy lines so I have to say is the Jumbo could also be considered as a Infantry Tank? that and/or can something like the Matilda or Churchill be considered as Assault Tanks? because to me (though albeit with amateur knowledge of tanks) are they both the same kind of tanks?

[@joaosabino2909]

South Africa use Centurian Mk3 upgraded each Centurion with a 29-litre Continental turbocharged diesel engine and a new transmission adopted from the M60 Patton.[74] The refurbished Centurions were also armed with a South African variant of the Royal Ordnance L7 105 mm main gun. In the early 1990s, the Olifant Mk1A was superseded by the Olifant Mk1B, which incorporated major improvements in armour protection, a slightly more powerful engine, a double armoured floor for protection against mines, and a torsion bar suspension.