Collections: When is a ‘Tank’ Not a Tank?

(There were some technical difficulties with this post when it first went live. They should be resolved now. My apologies for anyone who got multiple email updates as a result of efforts to get the post working.)

This week we’re going to look at everyone’s favorite kind of armored fighting vehicle, the tank. In part this is a response to my frustration – one shared by, it seems, quite a few people – at the continued inability for journalists in particular to correctly identify what is and is not a tank. But more importantly it provides an opportunity to discuss what tanks are and what they are for.

This isn’t going to be a real ‘deep dive’ into the development and design of armored fighting vehicles as that is a huge topic. Rather this is going to be a brief overview of how we got both tanks but also other tank-like objects which often get mistaken for tanks with some particular attention to what these various vehicles are for: what their role is and how that dictates elements of their design.

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Defining a Tank

Whenever this topic comes up, someone swiftly produces some version of this chart:

Or this somewhat more fanciful version:

So what defines a tank? If I was pressed for a hard definition, I’d say that a tank is a heavily armored and tracked combat vehicle whose purpose is to offer powerful direct fire capabilities against a range of enemy targets. This isn’t quite a doctrine-only definition, but it is certainly a doctrine-first definition; the technical details (heavy armor, tracks) actually both relate to the specific capabilities they provide (which we’ll get to in a moment).

But in practice, like many weapons and weapon-systems, the tank and its definition is rooted in its developmental history and the problems that tanks were created to solve. So…

Where Did the Tank Come From and Why?

We’ve actually already discussed this to a degree: the tank was a direct response to the battlefield conditions of WWI, in particular the trench stalemate on the Western front. The idea of some kind of armored ‘land cruiser’ (potentially armed with machine guns) had been floated before WWI but never seriously considered and developed on, but serious development only began in 1915 with the formation of the Landship Committee early that year. Famously, they needed a code-name for their planned vehicle and opted first for ‘water carrier’ and then for ‘tank,’ thus giving the tank its peculiar English name.

And we should stop to note that as with any question of definition, this one too is language-sensitive. The exact confines of a term vary from one language to another; kampfpanzer, for instance is not necessarily an exact synonym for ‘tank.’

In any event, the basic demands of early tanks were dictated by the realities of the Western Front: a tank needed to be able to resist small arms fire (particularly machine guns), deliver direct supporting fire itself, it needed to be able to move on the muddy, artillery-flattened ground and it needed to be able to cross a trench. This last requirement – the need to be able to both climb a parapet (usually c. 4ft) and then cross over an 8ft wide trench – was significant in the design of early tanks.

Via Wikipedia, a British Mark I tank (‘male’ meaning it has two quick-firing 6-pounder in the sponsons; you can see just one of them here, angled up).
There is one tank in this picture.

Those factors in turn dictated a lot of the design of early tanks. The armor demands of resisting small armies fire meant that the vehicle would be heavy (and indeed, as soon as tanks appeared amongst Allied troops, their German opponents began introducing more powerful bullets, like the K bullet and later the 13.2mm anti-tank round fired from the Mauser 1918 T-Gewehr). And here is the first advantage of tracks. The weight of a vehicle is distributed along all of the area of contact it has with the ground; with tires that area is limited to the bottom of the tire so the total area of ground contact is fairly low, which is fine for most vehicles.

Via Wikipedia, the French Renault FT-17, in this case in use by the United States Army. Smaller, lighter and relatively more reliable, the Renault FT was one of the more successful tanks of WWI, but the move towards larger and heavier tanks in the interwar period rapidly left it obsolete.
These are tanks.

But tanks are heavy. Really heavy. Even something like the Renault FT could mass around 7 tons and by later standards that would be classified as a tankette (a ‘mini-tank’ as it were); by WWII, medium tanks often clocked in around 30 tons. If you put a vehicle like that on tires, you are going to create a LOT of pressure on those small points of contact. That might still be OK if you are just going to drive on roads and other firm surfaces which can take the pressure. But remember: tanks were designed for the Western Front, which looks like this:

Via Wikipedia, no man’s land in Belgium, 1919.
This is not a tank.

Fortunately for the landship committee, this wasn’t a new problem: farming tractors were also heavy and also had to operate in churned up (in this case, plowed) soft soil; the heaviest of these vehicles had much the same problem and the solution was continuous tracks or ‘treads.‘ When kept properly tensioned – tune in, by the by, to Nicholas ‘The Chieftain’ Moran’s YouTube for more than you ever want to know about track tension – the track distributes the weight of the tank across the entire section of the track touching the ground, which reduces the ground pressure at any given point, allowing a big heavy tank to roll over terrain where even a much lighter wheeled vehicle would get stuck.

This is one of those points where the functionality of a tank (what a tank does) has such a strong influence on design that the design implications of the functionality become part of the definition: a tank has to be heavily armored and has to be able to move off road and as a result has to be tracked, not wheeled. One might be able to imagine some sort of exotic technology that might make it possible to do all of the things a tank does without tracks, but we don’t have that yet.

The other factor was fire. I’ve mentioned this before, but one of the significant background factors of WWI is that a lot of the belligerents misjudged the kind of artillery they’d need for a general European war. Not to get too deep into the weeds here, but most of the belligerents expected a relatively rapid war of maneuver and so thought that light, direct-fire1 artillery like the famed French ’75 (the Matériel de 75mm Mle 1897) would be the most useful. Those guns could be moved quickly and could deliver a lot of quick firepower on static or moving formations of enemy infantry in support of friendly infantry.

The problem is that in the conditions of trench warfare, those guns – as they were configured, at least – were far less useful. They were, first off, much shorter in range which meant they had to be brought dangerously far forward to do their direct fire role – often so far forward they could be engaged by enemy rifles and machine guns. This was compounded by the fact that direct fire at range was ineffective against trench works (which are dug down into the earth). But at the same time, the value of rapid firing (because these lighter guns could fire a lot faster than the heavy, indirect fire artillery) direct fire artillery remained high, if only you could get it to the fight.

Via Wikimedia, a ‘French 75’ light field gun; the formal name for this fast-firing and deadly light artillery piece was the Matériel de 75mm Mle 1897. Brutally effective in its role, the gun suffered from the fact that trench warfare increasingly prioritized heavy artillery over light, fast moving field guns like this one.
This is not a tank.

This was also a problem a tank could solve: as a mobile, armored platform it could move a rapid-firing direct fire gun forward without immediately being knocked out by enemy small arms to support the infantry. There is, I should note, early complexity on this point, with both ‘male’ (heavy direct fire cannon focused) and ‘female’ (machine gun focused) tanks in WWI though in the end ‘hermaphrodite’ designs with both capabilities (but much more focus on the main cannon) triumph, so that’s what we’ll focus on.

And that gets us the fundamental role structure for tanks: enough armor to resist enemy small arms (but with the understanding that some weapons will always be effective against the tank), enough mobility to cross the churned up battlefield and some direct fire capability to support the infantry crossing it at the same time.

Comes the Halftrack

The period between WWI and WWII – the ‘interwar’ period – was a period of broad experimentation with tank design and so by the time we get to WWII there are a number of sub-groupings of tanks. Tanks could be defined by weight or by function. The main issue in both cases was the essential tradeoff between speed, firepower and armor: the heavier you made the armor and the gun2 the heavier and thus slower the tank was. The British thus divided their tank designs between ‘cruiser tanks’ which were faster but lighter and intended to replace cavalry while the ‘infantry tanks’ were intended to do the role that WWI tanks largely had in supporting infantry advances. Other armies divided their tanks between ‘light,’ ‘medium,’ and ‘heavy’ tanks (along with the often designed but rarely deployed ‘super heavy’ tanks).

What drove the differences in tank development between countries were differences between how each of those countries imagined using their tanks, that is differences in tank doctrine. Now we should be clear here that there were some fundamental commonalities between the major schools of tank thinking: in just about all cases tanks were supposed to support infantry in the offensive by providing armor and direct fire support, including knocking out enemy tanks. Where doctrine differed is exactly how that would be accomplished: France’s doctrine of ‘Methodical Battle’ generally envisaged tanks moving at the speed of mostly foot infantry and being distributed fairly evenly throughout primarily infantry formations. That led to tanks that were fairly slow with limited range but heavily armored, often with just a one-man turret (which was a terrible idea, but the doctrine reasoned you wouldn’t need more in a slow-moving combat environment). Of course this worked poorly in the event.

More successful maneuver warfare doctrines recognized that the tank needed infantry to perform its intended function (it has to have infantry to support) but that tanks could now move fast enough and coordinate well enough (with radios) that any supporting arms like infantry or artillery needed to move a lot faster than walking speed to keep up. Both German ‘maneuver warfare’ (Bewegungskrieg) and Soviet ‘Deep Operations’ (or ‘Deep Battle’) doctrine saw the value in concentrating their tanks into powerful striking formations that could punch hard and move fast. But tanks alone are very vulnerable and in any event to attack effectively they need things like artillery support or anti-air protection. So it was necessary to find ways to allow those arms to keep up with the tanks (and indeed, a ‘Panzer divsion’ is not only or even mostly made up of tanks!).

At the most basic level, one could simply put the infantry on trucks or other converted unarmored civilian vehicles, making ‘motorized’ infantry, but as discussed a whole part of the design of tanks is to allow them to go places that conventional civilian vehicles designed for roads cannot and in any event an unarmored truck is a large, vulnerable tempting target on the battlefield.

The result is the steady emergence of what are sometimes jokingly called ‘battle taxis’ – specialized armored vehicles designed to allow the infantry to keep up with the tanks so that they can continue to be mutually supporting, while being more off-road capable and less vulnerable than a truck. In WWII, these sorts of vehicles were often ‘half-tracks’ – semi-armored, open-topped vehicles with tires on the front wheels and tracks for the back wheels, though the British ‘Universal Carrier’ was fully tracked. Crucially, while these half-tracks might mount a heavy machine gun for defense, providing fire support was not their job; being open-topped made them particularly vulnerable to air-bursting shells and while they were less vulnerable to fire than a truck, they weren’t invulnerable by any means. The intended use was to deposit infantry at the edge of the combat area, which they’d then move through on foot, not to drive straight through the fight.

Via Wikipedia, the US Army’s M3 Half-track (deployed in 1940). You can see how the protection it offers the crew and the passengers is not zero but still relatively minimal: you want to get out of these and move on foot once you are at the fight, since infantry can at least take cover as they move whereas a halftrack is a tempting target for enemy fire.
These aren’t tanks.

The particular vulnerability of the open-top design led to the emergence of fully-enclosed armored personnel carriers almost immediately after WWII in the form of vehicles like the M75 Armored Infantry Vehicle (though the later M113 APC was eventually to be far more common) and the Soviet BTRs (“Bronetransporter” or “armored transport”), beginning with the BTR-40; Soviet BTRs tended to be wheeled whereas American APCs tend to be tracked, something that also goes for their IFVs (discussed below). These vehicles often look to a journalist or the lay observer like a tank, but they do not function like tanks.3 The M113 APC, for instance, has just about 1.7 inches of aluminum-alloy armor, compared to the almost four inches of much heavier steel armor on the contemporary M60 ‘Patton’ Tank. So while these vehicles are armored, they are not intended to stick in the fight and are vulnerable to much lighter munitions than contemporary tank would be.

Via Wikipedia, a Soviet BTR-152, developed in 1949 and deployed in 1950. Note while fully enclosed, the purpose of this vehicle is transport, not fighting.
This is not a tank.

At the same time, it wasn’t just the infantry that needed to be able to keep up: these powerful striking units (German Panzer divisions, Soviet mechanized corps or US armored divisions, etc.) needed to be able to also bring their heavy weaponry with them. At the start of WWII, artillery, anti-tank guns and anti-air artillery remained almost entirely ‘towed’ artillery – that is, it was pulled into position by a truck (or frequently in this period still by horses) and emplaced (‘unlimbered’) to be fired. Such systems couldn’t really keep up with the tanks they needed to support and so we see those weapons also get mechanized into self-propelled artillery and anti-air (and for some armies, tank destroyers, although the tank eventually usurps this role entirely).

Self-propelled platforms proved to have another advantage that became a lot more important over time: they could fire and then immediately reposition. Whereas a conventional howitzer has to be towed into position, unlimbered, set up, loaded, fired, then limbered again before it can move, something like the M7 Priest can drive itself into position, fire almost immediately and then immediately move. This maneuver, called ‘shoot-and-scoot’ (or, more boringly, ‘fire-and-displace’) enables artillery to avoid counter-battery fire (when an army tries to shut down enemy artillery by returning fire with its own artillery). As artillery got more accurate and especially with the advent of anti-artillery radars, being able to shoot-and-scoot became essential.

Via Wikipedia, an M7-Priest self-propelled gun. Note that whereas a tank essentially took up much of the role of direct fire artillery, self-propelled artillery generally takes up the role of indirect fire artillery.
This is not a tank.

Now while self-propelled platforms were tracked (indeed, often using the same chassis as the tanks they supported), they’re not tanks. They’re designed primarily for indirect fire (there is, of course, a sidebar to be written here on German ‘assault guns’ – Sturmgeschütz – and their awkward place in this typology, but let’s keep it simple), that is firing at a high arc from long range where the shell practically falls on the target and thus are expected to be operating well behind the lines. Consequently, their armor is generally much thinner because they’re not designed to be tanks, but to play the same role that towed artillery (or anti-air, or rocket artillery, etc.) would have, only with more mobility.

So by the end of WWII, we have both tanks of various weight-classes, along with a number of tank-like objects (APCs, self-propelled artillery and anti-air) which are not tanks but are instead meant to allow their various arms to keep up with the tanks as part of a combined arms package.

MBTs and IFVs

As we get into the Cold War era, one thing becomes simpler: the distinction between different kinds of tanks (heavy, medium, light, cruiser, infantry, etc) largely4 drops away. Improved engines, suspension and lighter but more effective composite armor meant that the slightly different roles of the different weights of tank could increasingly be accomplished by a single platform evolving out of late-war medium tanks. You could now fit a heavy tank’s gun and armor on a chassis with a medium tank’s speed and maneuverability. The first of these ‘universal’ tanks was the British Centurion (first deployed in 1946)5 and other countries followed suit.

Via Wikipedia, Centurion, the world’s first main battle tank, having a favorable mix of armor, speed and firepower in a single platform.
This is a tank.

The result is the modern ‘main battle tank’ (MBT), typically between 45 and 75 tons, with a single powerful direct-fire cannon as its primary armament. That’s not to say design differences between militaries drop away; there are still decisions to be made: the level of emphasis between speed, armor and firepower for instance. Another major decision is whether a tank is designed with a three-person turret (one of whom is a dedicated loader) or a two-person turret with an autoloader (that is, a machine that does the loading for you). It used to be that now I’d have to go on about why going autoloaders aren’t simply obviously the best but given the live demonstrations of some of the drawbacks of Soviet/Russian carousel autoloaders going on right now I’ll just say that both options have advantages and drawbacks and move on. So there is variety within the idea of an MBT, but by and large most countries field just one type of MBT (or one family of MBTs for countries which can’t afford to retire older systems) and that covers their tank needs.

From Rob Lee’s twitter feed, a destroyed Russian T-72B3 with the turret having been blown off. This happens because the ammunition in the carousel autoloader ‘cooks off’ when the body of the tank is struck and penetrated by enemy fire. The structure of an autoloader makes keeping ammunition secure and channeling any ammunition explosion to the outside of the tank more difficult, but the carousel autoloader design of the T-72, T-80 and T-90 tanks is particularly poor at this. Crew survivability in these cases is extremely low.
This was a tank.

But of course nothing could easy so just as tanks were getting easier to keep track of, APCs get much more complicated. Even before they were fully enclosed, APCs had generally carried some kind of defensive weapon (usually a heavy machine gun), but you weren’t supposed to fight with it if you could avoid it. Beginning in the 1950s, designers – first in West Germany – began experimenting with the idea that an APC could be armed to not merely deliver the infantry (‘dismounts’) but to actually fight when they got there. The thing is, there are a lot of situations where an infantry formation might want more firepower but where a tank would be overkill: armored vehicles lighter than tanks, or enemies with lighter fortifications, for instance. West Germany pioneered the idea by putting a 20mm autocannon on their APC, the Schützenpanzer Lang HS.30, enabling it to put out some meaningful firepower, albeit much less than a tank.

Via Wikipedia, a Schützenpanzer Lang HS.30 currently in the German Tank Museum. As you can see, it is still mostly an APC, with the turret not being the main focus of the design, but nevertheless offering substantial firepower.
Despite its location, this is not a tank.

The USSR cottoned on to the idea and liked it, resulting in the Soviet BMP-1 and the subsequent BMP family of what we call ‘infantry fighting vehicles’ (IFV). Initially resistant to the idea (American doctrine was that APCs move troops and should not fight if they could help it), the United States, noticing the effectiveness of these sorts of platforms, got into the act with the Bradley Fighting Vehicle (these days the M2 Bradley). And IFVs, especially the Bradley, look like tanks. And indeed, they are sometimes called on to do the kind of armored reconnaissance and infantry support jobs that in a previous era would have gone to a light tank.

Via Wikipedia, a BMP-3, prominently displaying both its main armament and the All-Purpose Soviet Log attachment (The USSR may be gone, but the All-Purpose Soviet Log survives!). You can see the evolution in design: greater emphasis on the weapon, but this is still primarily a troop transporter with a lot of internal space for the purpose.
This is not a tank.

But they are also notably not tanks in several key ways. The primary job of an IFV is to move infantry and support them against lighter targets; some IFVs do maintain some kind of anti-tank capability, but it tends to be more limited (e.g. the Bradley’s pair of TOW AT missiles). The requirement that an IFV needs to be fairly fast but also needs to fit a bunch of dismounts means they can’t carry the firepower or the armor of a tank, often using lighter aluminum armor rather than steel or heavy composites. Finally, the tendency is for IFVs to mount lighter primarily armaments – again, space and weight concerns – like the Bradley’s 25mm M242 Bushmaster chain gun. The BMP-3 is probably the most heavily armed IFV out there with a low-velocity 100mm rifled gun and a 30mm autocannon, which is still a far cry from the firepower of the high-velocity 125mm main gun of a contemporary T-80 or the 120mm high velocity gun of a M1A1 Abrams. Instead, most IFVs would rely on anti-tank missile systems to engage tanks (although IFV autocannons can cause a tank serious problems if they can engage the rear or side armor, which is thinner).

Via Wikipedia, the Bradley (in this case, M3), probably the single worst not-a-tank offender for its appearance. One thing that confuses people in this is scale: the Bradley is taller than the Abrams (just about 10ft to 8ft), so it is easy to mistake the proportions. Moreover that height also goes towards the design consideration: tanks, because of their offensive role, need to have lower profiles so they can fire and then hide behind things (‘turret down’ or ‘hull down’ position); the Bradley’s role is different – it has to fit a bunch of dismounts and/or scouting gear – and so it ended up a lot taller.
This is not a tank.

Note that the IFV did not mean the end of the APC just as the APC didn’t bring the end of soft-skinned troop transports. In the US military, the Bradley serves alongside lighter-but-still-IFV Strykers, the venerable M113 APC along with soft-skinned HMMWV (Humvees; to be in theory replaced with the Oshkosh6 L-ATV) and trucks of various kinds and uses. Likewise, the Russian army has its BMPs (which are IFVs), and BTRs (which are APCs) as well as soft-skinned vehicles – or at least it did until, I am now being told, they were all towed away by Ukrainian farmers. The real Iron Harvest.

The final category worth noting here are variations on the concept of the MRAP (Mine-Resistant, Ambush-Protected): infantry transport vehicles designed to resist the sort of dangers one encounters in counter-insurgency operations, mostly mines, IEDs and small-arms ambushes. In essence, these vehicles are a purpose-built version of the up-armored Humvees designed to operate in a very particular combat environment (insurgencies and particularly urban insurgencies). These sort of vehicles have gotten more visibility in the United States because many of them have been shifted into the hands of law enforcement, where their utility is questionable, to say the least.

Via Wikipedia, a set of Caiman MRAPs deployed in Iraq. I actually use this vehicle when talking to my students to talk about trade-offs in the kind of conflicts a force prepares to fight, because the improvements that make an MRAP safer in an urban insurgency would render it much less viable in a large-scale conventional conflict than thinner-skinned, less well armored (but lower profile and faster) vehicles.
These are not tanks.

So What is a Tank?

In many ways, the role a tank fills hasn’t changed much since WWII when ‘engage other tanks’ was added to its list of jobs: tanks provide offensive ‘punch’ and firepower to allow infantry to advance, seize ground and maneuver in an environment where, thanks to machine guns, even small enemy forces can put out a lot of bullets to otherwise prevent infantry from doing those things. Tanks also need to engage other armored vehicles and potentially fortified positions. Doing those two jobs require that tanks heave the heaviest armor and the heaviest main gun possible, which both precludes them doing other things (like moving infantry) while at the same time demanding that they be tracked in order to manage the weight of that stuff.

I don’t think a tank needs to have a turret, by this definition, to be a tank, but most tanks have turrets. But many non-tanks also have turrets. The key here is role and function, not any particular design element.

Via Wikipedia, the Swedish Stridsvagn 103 or ‘S-tank’ (in service from 1967 to 1997) is a rare example of a turretless tank, though it is worth noting that Sweden’s later tanks are turreted.
This is a tank.

What has changed is that tanks have gone from being effectively the only armored vehicle on the battlefield to working in concert with many other armored fighting vehicles, which have different roles. IFVs, in particular, can blur the line a bit between a tank and an APC, but in most cases the differences in design, firepower and thus capabilities between a tank and an IFV is massive; attempting to use IFVs like tanks is a good way to lose a lot of IFVs.

Is the tank on the way out? I don’t think so. Nicholas ‘The Chieftain’ Moran did a fairly good overview of the question, but the key point here is that the design of the tank is dictated by its battlefield function and there still isn’t anything out there that does a tank’s job better than a tank does; IFVs and other AFVs have to make pretty clear compromises in armor protection and firepower to accomplish their main roles. And while the public may be discovering the vulnerability of the tank for the first time, tanks have always been vulnerable to a wide variety of threats and have always required supporting arms to mitigate (but not remove) that vulnerability.

Now does it matter that the general public cannot tell the difference between a tank and an IFV? No, it probably doesn’t, to be honest. But it does matter that journalists covering wars and politicians making decisions about them also don’t seem to be able to, because it hints at a broader gap in the base of knowledge they are working with. “Bradley/BMP-3 isn’t a tank, but something else (an IFV) with a different function and purpose” is a fairly entry-level piece of information about modern warfare. And at some points that information gap can be abused, as when the German ambassador to the United States described Germany sending ‘Gepard Tanks’ to Ukraine:

Presumably Emily Haber was attempting to avoid a truer description of the event which would have been, “Germany is sending largely obsolete self-propelled anti-air platforms, the Flakpanzer Gepard, to Ukraine.” A journalist who is actually qualified to be covering a modern conflict ought to immediately be able to call this out as, at best, an unfortunate mistake (if not an intentional error). But journalists often sadly lack that kind of domain-specific knowledge, which really hurts their ability to inform the public.

(Edit: It seems worth clearing up confusion here about the German word panzer. While it is often translated as ‘tank’ (and so Flakpanzer gets translated as ‘Flak-tank’ or ‘AA-tank’) that’s not really right. Panzer means ‘armor,’ thus kettenpanzer is the German word for mail armor (one of them, anyway), “chain armor” literally. The direct German equivalents for ‘tank’ are the older panzerkampfwagen (‘armored fighting vehicle’ but in use clearly means ‘tank’) or the more modern Kampfpanzer. Of course you can just use panzer in German to mean ‘tank’ just as in some cases you can use ‘armor’ in English to mean tank (“enemy armor, coming down the road!” means tanks, not a procession of breastplates). That said, this article was fundamentally about the usage in English where ‘tank’ is more narrowly defined than panzer is in German. Equipment terminology actually tends to be very language-specific in terms of what it includes and excludes.)

In any case, here is the terminology shorthand: any armored fighting vehicle is an ‘armored fighting vehicle’ (AFV – convenient, huh?); that includes tanks, but also self-propelled artillery and self-propelled anti-air, IFVs, MRAPs and APCs. A tank is an AFV whose purpose is to offer powerful direct fire capabilities against a range of enemy targets (infantry, buildings, other tanks and other AFVs); tracks, while not a dead giveaway are good to look for. Not all tracked AFVs are tanks, but all tanks are tracked AFVs because of the demands that the weight armor and firepower place on them. If you take an APC and put big gun on it, it becomes an IFV, not a tank. If you take a truck and put a big gun on it, it becomes a technical, not a tank (but that’s a story for another post).

This post is not a tank.

This, however, is a tank.

Edit: Turning the Post off and on again.

Edit2: For some further viewing if you want to know more about the development of armored fighting vehicles of all kinds, may I suggest the videos of Nicholas ‘The Chieftain’ Moran and Bernard Kast, the latter of whom has a channel, Military History Visualized. Both are great channels that I particularly like because they foreground their sources, be that surviving examples of equipment, academic literature or doctrine publications.

  1. That is, guns that fire in low arcs towards their targets. The opposite is indirect fire, where the projectile is shot mostly up to fall on the target.
  2. Technically here a major issue is also the size of the gun, since a larger gun means a bigger turret, which means a much heavier tank
  3. At least not against well-armed enemies. It is worth noting that, when fighting against enemies who lack access to effective heavy weapons and also don’t have any armored platforms of their own that would require something more powerful than a heavy machinegun, APCs could be used as a sort of ‘poor man’s tank.’
  4. With some exceptions
  5. You really feel for the British, whose tank designs during WWII often left a lot to be desired and it is only as the war is basically over that they stumble on one of the best tank designs ever in Centurion.
  6. B’gosh

357 thoughts on “Collections: When is a ‘Tank’ Not a Tank?

    1. It’s not visible on desktop either for me, although I can see the text in the email newsletter

    2. Not on Firefox or Chrome on a Win10 PC either. Can be read in the notification email I got.

    3. Not just mobile, I can’t see anything on my laptop either. It’s not browser dependent either

    4. It’s not even visible in the source. The part where it should be ( div class=”entry-content” … /div ) is empty ( angle brackets around tags omitted on purpose to avoid weird html parsing bugs, just to stay on the safe side). On the other hand the wordcount and the meta datas are OK. So the article did exist at some point, there is a trace of it in the WP table, but the database entry corresponding to the text is empty. Looks like some slightly-too-hurried ctrl+X before closing the browser and going for dinner (or Friday beer). 🙂

      I sure hope there is a backup copy of the text somewhere…. :-/

  1. Off-topic question. I’m thinning my library and found I bought but never read:

    Ferrill, Arther. “The Origins Of War: From The Stone Age To Alexander The Great” 1985)

    Worth reading, or not?

  2. Article is not visible. Firefox on Ubuntu Linux desktop. Same with Chromium (Linux Chrome port).

    1. His sudden shift to writing zen koans is unexpected. However, I will think upon the tank that isn’t, like the sound of one hand clapping.

  3. I read the article when it was delivered by email. I don’t see it on this page, either.

    I’m starting to wonder about the operational utility of AFVs in general, including tanks. The Ukraine-Russia war has pointed up that modern man-portable anti-tank missiles are really effective. The Javelin is thirty year old technology, and it’s pretty well stopped Russian armored assaults cold. Now, this may be because the Russian Army isn’t good at combined arms operations, but talking to a friend in the National Guard he made the same comment: A dude with a Javelin in a prepared position is almost impossible to spot before he fires. And since the Javelin is fire-and-forget there’s no counter once he’s pulled the trigger.

    So as long as an army can identify attacks in advance (modern drones are making this real easy) and move reinforcements to a planned attack point for a hasty ambush, then a modern tank attack never gets off the ground. The counter to this, of course, is to establish air superiority and shut down your enemy’s ability to reinforce. Russia has, uh, not been able to do that.

    I’m starting to think that we’re returning to a high-technology version of the WWI stalemate. Defensive systems have gotten so good that they can blunt any attack and leave the attacker open for an infantry counter-attack. The jury is, of course, still out on this. But it looks a lot more probable than it did three months ago.

    The moral of the story, of course, is buy Raytheon stock. A whole lot of Javelins have been consumed, will continue to be consumed, and Raytheon is going to get a contract to refill inventories.

    1. Hasn’t it been doctrine since… well… forever, that a tank force is supposed to be screened by infantry or at the very least lighter armored or mobile elements, though?

      Like during the push on Kiev I kept seeing all these videos of Russian columns being hit from prepared defensive positions as they trundled merrily along, and just thinking “where are your footsloggers? Where is your recon? Why don’t you have screening out? I’m not seeing any light vehicles out there that can respond with agility. You just rolled your heavy stuff in completely exposed?”

      1. “A Bridge Too Far” revived? I found it hard to believe that they could’ve be so unprepared, but then, Russia over the past few years has had pretty much the same problems the Weimar Republic faced with corruption, and a lot of the resources that would’ve otherwise wound up in triaing, undoubtedly got spent by others elsewhere.

        1. Less then the lack of preparedness, though there was definitely that, is (in my view) expectations completely contrary to reality. Much of Russian decision making in how the war was prosecuted in the early days makes sense if you assume they expected the Ukrainian military to fold as in Crimea and for there to be a large number of pro russian operatives moving in concert with the invasion to show panic and confusion. Had these two things been true, everything would have gone far better for Russia and we would probably be talking about how dangerous the Russian army clearly is. This invasion has showcased a monumental inteligence failure by Russia and a spectacular inteligence success by the US.

          1. Hmmm. Does not figuring out that your operatives embezzled the money meant to corrupt key enemies figures qualify as an intelligence failure? Or is the failure in hiring such corrupt operatives?

            The fires in Russia may have been destruction of evidence.

        2. While I agree that Russia has had huge problems with corruption that have clearly weakened their military preparedness, I don’t know that the Weimar Republic had such problems as you imply it did, Potkoorok.

          Weimar had an army whose size was limited by treaty regulations, and very good reasons to focus on economic reconstruction. It had to start out devastated by World War One and certain amount of low-level civil war against some internal factions, and just as it was getting things back together, the Depression hit. I don’t doubt that the German army under the Weimar Republic was less well funded than it would have liked, but I don’t think corruption was the explanation.

    2. Well, it can be said generally that any weapon system or combat arm will fail if used incompetently- and the Russians used their armor, at least around Kiev, very incompetently indeed. Rolling through built-up areas in column with no dismounts screening for them? They might as well have carried signs saying “Ambush Us”

    3. The operational utility of tanks is their ability to deliver fire to a target, not their invulnerability. For over a century there have been advancements in the ability of non-tank forces to kill tanks but the tank continues remains useful. During the 1950s and 1960s the ability of any armor to stand up to the munitions of the day was so woeful that tanks like the Leopard 1 and the AMX 30 were built with barely any armor at all, if even HEAT warheads against steel armor wasn’t able to prove the tank (and other AFVs) obsolete, I doubt top attack munitions like the javelin will matter much. It’s also likely that active protection systems will soon be developed which can engage top attack munitions as well as strait in ones if there aren’t already systems available with that capability. The tank has always been vulnerable, even during the first world war.

      As to your second point about drones improving recon to the point where tank attacks are useless, I’m doubtful. Battlefield reconnaissance may be better now than ever before, but tanks aren’t solely useful in massed assaults, and infantry are likely even more vulnerable in this situation than armor. While the use of drones in this war and the Nagorno-Karabakh war shows their utility, I’m certain militaries are taking notes and anti drone weapons will soon degrade the utility of small drones for both reconnaissance and attack.

      To your third point, I don’t really know enough to outright deny it beyond saying that this war has not been static, the Russians have made significant advances in the south, and have been unable to hold the positions captured in the north of Ukraine, which seems to make claims that it’s a world war one style stalemate seem premature.

      Lastly yeah, I’m sure Raytheon’s shareholders are very happy right now.

      (A note on my arguments, I’m not an expert on this subject and am mostly paraphrasing people more knowledgeable than me on this subject, my only qualifications are that I once was far too interested in military matters.)

      1. As other methods of delivering fires improve (from ICBMs to drone strikes), will there still be a place for the tank as a munitions delivery system? Or will the tooth end of armies end up being composed entirely of such long-range munitions and the infantry needed to support them?

        1. Probably there will be a place for them. Even today, most fires being delivered are “light” (fragmentation/shrapnel, or bullets) and thus it is valuable to have some stuff that is resistant to them. The condition to the situation changing is that if armor-cracking fires become cheap enough to replace “light” effects, i.e. armies start shooting enemy _infantry_ with ATGMs rather than unguided HE (or rifles).

          To a first approximation, the point of spending organizational capacity (and money) on having AFVs alongside unarmored things is that it forces the enemy to spend organizational capacity (and money) on maintaining two separate effect delivery systems (plus AA), one against each. Just as you build walls so that the enemy must spend the effort to siege them. Also note that starting from WW1, some degree of personal armor for infantry — which usually “only” protects against fragmentation/shrapnel, not bullets — has been often experimented with, and some elements i.e. the helmet are ubiquitous.

          Alternatively, even if everything is armored to some degree — with the corresponding expense — that still makes them survive a given intensity of enemy fire better.

          Of course, there are other reasons, such as casualty minimization even for incapacitation. And the Baumol effect: since the people who serve in the military could get earn a wage as civilians, (Western) Great Power militaries find that the cost of getting an additional soldier into the tooth is so high that they might as well spend a lot of money on armoring them.

          1. I forgot to mention that it has happened before. From the Stone Age to the end of the Medieval era, armor was common. Then handheld firearms became so cheap and so performant that by the Napoleonic wars, some of the major belligerents had completely phased out armor (and even the others only had breastplates for heavy cavalry). From WW1 to some point in the future is the second era of armor.

    4. “The Ukraine-Russia war has pointed up that modern man-portable anti-tank missiles are really effective.”

      Bullets have been really effective for a very long time, and at no point in that really long time have we abandoned infantry. Because there is nothing around that can do the same jobs as an infantryman, and is resistant to bullets. And what is going to replace the tank, except a higher-tech tank?

      If you prefer The Chieftains take: https://www.youtube.com/watch?v=lI7T650RTT8&t=7s

    5. As far as I know, one of the strong points of tanks is that they are not (much) vulnerable to artillery – unlike your two guys on a jeep with a javelin. Your tank-free force would be flattened by artillery (or close air support) in no time.

      It ends up being a complex game of rock-paper-scissors (tank-infantry-artillery), which is of course why modern armies use combined arms… and maybe, too, while training, doctrine, command and morale matters a lot. What wins the war is not the meanest tanks or the biggest guns, but the smart use of all of these in combination.

    6. “So as long as an army can identify attacks in advance (modern drones are making this real easy) and move reinforcements to a planned attack point for a hasty ambush, then a modern tank attack never gets off the ground.”

      “So long *as*” is doing an awful lot of heavy lifting there. Combat is not a game of Rock, Paper, Scissors.

      While modern communications, increased stealth and range of recon, and increased weapons range have made things much easier… Automagically being in the right place at the right time with both recon assets and combat formations is still a Very Hard Problem. And that’s separate from the Fairly Hard problem of being able to set up a timely and effective ambush.

    7. The Israeli Trophy point defense system appears to have a pretty good record at protecting a tank against incoming ATGMs.

      It is still a contest between attack and defense capabilities.

    8. I learned to take on tanks with a panzerfaust nearly 30 years ago, there is not much new in this now except drones.
      And as the chieftain retold us , tanks without infantry support are relative easy prey for infantry who has the right tools and nows what she is doing

      1. Same. We also trained close ambushes, with with Handfllamm or a Molli to blind, and an AT mine or just a lot of TNT, hand–delivered to contact, to kill.

        Presupposes unsupported tank and close terrain, and is not for the casualty-averse, but can be effective.

    9. I am completely unconvinced AFVs as a whole are on the way out and skeptical regarding tanks. Even if it’s not practical to armor against ATGMs and we fail to go CNC Generals Paladin Tank style with active defenses, there’s going to be a call for armor that can stand up to SAWs at the very least, and mobility for infantry is more critical than ever. Modern artillery means defenses can’t be static in rhe way they used to be; you’re going to need to move infantry quickly to set up that hasty ambush and then get out of there.

      It is possible we’ll ditch most of the tank armor in favor of speed, or like aircraft we’ll start using flares and such to confuse the guidance systems and our future tanks will be IFV hulls with a 120mm high velocity cannon. It’s also possible materials scientists will come through in a big way and cut armor weight enough to put Javelin-proof armor on tank roofs.

  4. This was helpful. One element that wasn’t included was the scale of soldiers carried by IFVs and other non-tank AFVs. It looks like the Bradley normally carries about 6 fully-kitted out soldiers. Seems like not many, but then again a HMMWV only carries 3 or 4, so it’s actually pretty robust.

    1. German SdKfz 251’s & American M3’s carried a squad, but German SdKfz 250’s & British carriers held roughly the equivalent of what we call a fire team now. That is roughly what IFV’s transport now.

        1. It varies a bit but a squad is around ten and a fireteam is half of a squad, generally.

  5. I really admire your boldness on some of these claims, Doc. “If it’s wearing a dress, it’s a tank.” I mean, the mind reels! Does that mean Harry Styles can be classified as warfighting equipment? Amazing!

    ***this is sarcasm based on the fact the text isn’t visible***

  6. So I guess we are left to ponder this question on our own for a while before we can read the article and see Bret’s thoughts on the matter.

    1. I see the article now, but I can’t comment using my WordPress account as I usually do.

      1. I still can’t see the article, but I can comment using my WordPress account.

        Checked the page source to see if I could read it there, but no dice. Which is probably for the best—reading source-formatted text sounds like a colossal pain!

  7. I think the comment of the german ambassador regarding the Gepard-“tank” is most likely an error due to different definitions in german and english: in german, the term “panzer” is used much more broadly and also applied to the Gepard, a so called “flakpanzer”. “Panzer” is then simply translated to “Tank” (just try it in Google translate). Thereby, all the nuance you brought up here is lost.

    1. Interestingly, drones have resuscitated the flakpanzer – radar, optics and and fire-control system integrated with 40 mm AA are effective against drones.

  8. I would excuse the German ambassador. It is maybe even more complicated in German where every armoured vehicle is a …panzer. And “Panzer” means tank, so it has to be an tank in English, right?

    But …panzer should most often juste be “armoured” in English. So of the Kampfpanzer, Flakpanzer, Schützenpanzer, … only one of them is actually a tank.

    1. but all are part of the Panzertruppen litterally tank troops or tank branch from which the Panzertruppe the tank corps or branch is also a branch

      1. Not all. Schützenpanzer belong to the Panzergrenadier units, which are a subset of the infantry, and carry the green Litzen to prove it (Panzertruppe have pink Litzen).

        1. Last time i looked the panzergrenadiere have been part of the armoured branch.
          The Infantry branch includes the Jäger(classic infantry) Fallschirmjäger(Paratroopers) and Gebirgsjäger(Mountain troops)

    1. tank. but being used in an unconventional role. it is literally just a regular merkava that has had most of its ammunition removed to allow some stretchers and wounded to be carried. it is still capable of acting as a tank (which was the point), just for not as long. i honestly expect the number of merkava’s used for medivac to drop as the Namer becomes more common, since it offers the same armor protection (they reason they were using tanks for the role, since normal softskins and APC’s were being shot up since their enemies didn’t follow international laws regarding medical vehicles) without taking a MBT off the combat line. the ‘tankbulance’ was of questionable legality and wouldn’t really be useful against anyone but insurgents. it carries heavy weapons so thus does not get protections from enemy fire that medical vehicles usually get under international law, the only reason they bothered was the fact they needed heavier armor to protect the injured. the Namer has that armor to protect the injured, while also being able to meet the criteria for legal protections when fighting an enemy that actually follows those.

  9. I’ve heard it alleged that Russian doctrine is operating under a particular handicap: their regular forces are optimized to operate during a nuclear war, which imposes constraints that it doesn’t actually have to counter in Ukraine. To what extent is that true or significant?

    I know that tanks have certainly influenced nuclear weapon design. The neutron bomb, for instance, was created to destroy tank columns that had become heavily armored enough to survive nuclear blasts from only a few km away from ground zero, but couldn’t block the direct radiation from a neutron-optimized weapon. Then the concept got abandoned when tanks became so heavily armored that they could survive that, to.

    But clearly, other, much more lightly armored AFVs could not. So how did nuclear weapons, both direct strikes and fallout, affect design and doctrine of AFVs? I must have been considered quite heavily.

    1. I’ve seen another description of how Russia is supposed to fight, which argues against nuclear expectations being a problem. Plus Russia has fought other wars, and the soviet military trained a lot of others that were able to fight well. Though if nuclear defense was a problem, that would speak poorly to planning anyway, since Russia has already fought several wars that didn’t have nuclear weapons and presumably could prepare accordingly.

      The description I heard about how Russia is supposed to fight is something like:

      1. Tanks and artillery are what the military is focused around.
      2. Combined arms is important, getting the above and everything supporting them to work together is obviously very important
      3. The individual fighters/units aren’t necessarily that good, so large numbers are used.
      4. Lots of work is on higher level commanders, to make sure lots of forces are where they are most important. Idea is that even if individual units aren’t that great, they are concentrated in the right places to win well anyway.
      5. An actual logistics system exists: supplies are sent forward automatically, units are expected to fight until worn down, than sent back for repairs/to be built up again and replaced with others.
      6. More focus on anti-air defense than on a powerful air force, though obviously Russia is (supposed to) have a powerful air force anyway.
      7. Deception and detailed planning are highly valued.

      Problem seems to be the country falling apart after the cold war, plus corruption, and this means even the things they are supposed to do well aren’t performing at all. Deception got busted pretty quickly by U.S. intelligence it seems, a logistics system of “buy substandard stuff and sell equipment off” is not an effective one. High level people must be skilled in this sort of system, but they are as likely as not kissing up to Putin. Drafted armies with a similar organization to Russia I think (this is a vague impression, not systematic research) can be organized to work well, but tons of hazing + other bad conditions + corruption and such seems to have eaten into this. What’s left is “lots of tanks and artillery attacking”, which is enough to force a tough stalemate/hard fought war, but not terribly effective for what Russia seems like it should be capable of doing against a country with 1/10 the economy and 1/3 the population.

      1. Also, some of the ideas the Russians bought into may have been actively bad. (4) and (7) are particularly serious issues.

        Regarding (7), it’s all very well to build complex, detailed, deception-heavy plans. But if you don’t have the ability to cope when those plans don’t work out quite right, then training your troops to shut up and follow the plan results in them getting cut to ribbons.

        And that chains into (4). Putting the burden of not only formulating these complex plans, but also being the only one who can alter the plan in response to unexpected events, puts a very high strain on senior Russian commanding officers. Even with the best communication and intelligence gathering equipment in the world (and Russia has never had such good systems), that’s a weakness. It causes all kinds of bad results.

        A Russian commander simply forgetting something important can cause a disaster, because subordinates who can see why there is a problem with the suggestion are not free to alter the plan. A Russian commander whose unit is in a bad situation will be constantly desperately busy, even more so than in other armies, and will soon enough grow tired and confused from the burden of having to do all the thinking himself. And since situations often become too complex to understand over the phone, especially when the enemy may be listening to electronic communications… This forces Russian commanders to frequently go close to the front to sort out relatively simple problems. Which helps explain why the Ukrainians have been racking up a steady body count of dead Russian generals.

        The Soviet doctrine would probably work a lot better in a better prepared force whose budget wasn’t being devoured by corruption. But that doesn’t mean it was always good.

    2. Not an expert … my understanding is that designing AFVs to fight on a nuclear battlefield ends up being more or less the same problem as designing against biological or chemical weapons, hence the “NBC” acronym often used. (And also warships.)
      Armour against a nuclear blast isn’t really practical for something that also has to move. Your AFV is either too close and gets destroyed, or further away and survives. Most seem heavy enough not to worry about being tipped over by the shockwave.
      AFVs are typically a metal box, which is good protection against radiation. But I have no idea what happens when radiation hits composite materials or glass reinforced plastics.
      After the initial blast, the major threat is fallout. So an NBC tank can be sealed up as much as possible, with a “positive air pressure” system so that if there are gaps and leaks, air flows out of the tank, not in. Which happens to be what you also need to protect against biological and chemical weapons too.

      (Pedantic note: up to the early 21st C “biological weapons” are viruses and germs being dropped somehow on your enemy. Not genetically engineered velociraptors.)

      1. “But I have no idea what happens when radiation hits composite materials or glass reinforced plastics.”
        Ionizing radiation at high intensity and at close quarter? Consider how GRP items get degraded by constant, relatively low-intensity ionizing radiation in the open, whether at sea or on land. I can’t think of any stidy on the matter off-hand, but your local friendly mechanic will probably have war-stories of his or her own to tell about GRP items under those conditions.

      2. Protecting an AFV against Sarin gas is a lot harder than protecting it against velociraptors, given that an AFV already carrier a gun and bullet-proof armor.

  10. Reading the early history of the tank up to the Centurion put me in mind of nothing so much as the development of the dreadnought battleship: a period of a couple of decades of experimentation with different designs, weights, armaments, etc. ending with the wholesale adoption of a design that is large, heavy, well-armoured, relatively fast, and with armaments principally focussed on destroying its counterparts rather than suppressing lighter adversaries (infantry, torpedo boats, etc.)

    It seems too neat, but both development patterns make sense, for broadly speaking the same reasons.

    1. That’s an interesting take, and one that makes sense to me.
      Though it’s interesting that the dreadnaught revolution proceeded the war by enough that by the time the British and German fleets seriously clashed most of their battleships involved were of the new dreadnought type. If the war had been several years earlier there’d be few enough dreadnaughts that they’d probably have to primarily operate in formation with the pre-dreadnoughts they technically obsoleted. (Because if one side left them behind to take advantage of the higher speed of the new ships the other side would have too many hulls and guns for the handful of dreadnoughts to be able to take on.

      And conversely the Centurion MBT came just a few years too late to make it’s impact on WWII. Imagine seeing formations of those in North Africa or rolling out of Normandy instead of the mix of tanks that were there. And while it’s a lot quicker to build new tanks than new battleships if the design had gone into production during the war you likely wouldn’t have enough to replace all the previous designs; so they’d need to work in conjunction with the tanks they’d obsoleted. Doing so with cruiser tanks or Shermans is probably okay – use the Centurion initially like a faster and more reliable heavy breakthrough tank using it as your even more armored spear tip to help punch the lighter but also reasonably quick tanks through then all can spread out to help exploit exploit a breakthrough. But I don’t know how it’d work well with the slow infantry tanks – you’d need to hobble it greatly holding it down to their speed.

  11. Here’s the text of the post for anyone having trouble:

    This week we’re going to look at everyone’s favorite kind of armored fighting vehicle, the tank. In part this is a response to my frustration – one shared by, it seems, quite a few people – at the continued inability for journalists in particular to correctly identify what is and is not a tank. But more importantly it provides an opportunity to discuss what tanks are and what they are for.

    This isn’t going to be a real ‘deep dive’ into the development and design of armored fighting vehicles as that is a huge topic. Rather this is going to be a brief overview of how we got both tanks but also other tank-like objects which often get mistaken for tanks with some particular attention to what these various vehicles are for: what their role is and how that dictates elements of their design.

    As always, if you like what you are reading here, please share it; if you really like it, you can support me on Patreon. And if you want updates whenever a new post appears, you can click below for email updates or follow me on twitter (@BretDevereaux) for updates as to new posts as well as my occasional ancient history, foreign policy or military history musings.

    Defining a Tank
    Whenever this topic comes up, someone swiftly produces some version of this chart:

    image-10

    Or this somewhat more fanciful version:

    image-11

    So what defines a tank? If I was pressed for a hard definition, I’d say that a tank is a heavily armored and tracked combat vehicle whose purpose is to offer powerful direct fire capabilities against a range of enemy targets. This isn’t quite a doctrine-only definition, but it is certainly a doctrine-first definition; the technical details (heavy armor, tracks) actually both relate to the specific capabilities they provide (which we’ll get to in a moment).

    But in practice, like many weapons and weapon-systems, the tank and its definition is rooted in its developmental history and the problems that tanks were created to solve. So…

    Where Did the Tank Come From and Why?
    We’ve actually already discussed this to a degree: the tank was a direct response to the battlefield conditions of WWI, in particular the trench stalemate on the Western front. The idea of some kind of armored ‘land cruiser’ (potentially armed with machine guns) had been floated before WWI but never seriously considered and developed on, but serious development only began in 1915 with the formation of the Landship Committee early that year. Famously, they needed a code-name for their planned vehicle and opted first for ‘water carrier’ and then for ‘tank,’ thus giving the tank its peculiar English name.

    And we should stop to note that as with any question of definition, this one too is language-sensitive. The exact confines of a term vary from one language to another; kampfpanzer, for instance is not necessarily an exact synonym for ‘tank.’

    In any event, the basic demands of early tanks were dictated by the realities of the Western Front: a tank needed to be able to resist small arms fire (particularly machine guns), deliver direct supporting fire itself, it needed to be able to move on the muddy, artillery-flattened ground and it needed to be able to cross a trench. This last requirement – the need to be able to both climb a parapet (usually c. 4ft) and then cross over an 8ft wide trench – was significant in the design of early tanks.

    image

    Via Wikipedia, a British Mark I tank (‘male’ meaning it has two quick-firing 6-pounder in the sponsons; you can see just one of them here, angled up).
    There is one tank in this picture.
    Those factors in turn dictated a lot of the design of early tanks. The armor demands of resisting small armies fire meant that the vehicle would be heavy (and indeed, as soon as tanks appeared amongst Allied troops, their German opponents began introducing more powerful bullets, like the K bullet and later the 13.2mm anti-tank round fired from the Mauser 1918 T-Gewehr). And here is the first advantage of tracks. The weight of a vehicle is distributed along all of the area of contact it has with the ground; with tires that area is limited to the bottom of the tire so the total area of ground contact is fairly low, which is fine for most vehicles.

    image-1

    Via Wikipedia, the French Renault FT-17, in this case in use by the United States Army. Smaller, lighter and relatively more reliable, the Renault FT was one of the more successful tanks of WWI, but the move towards larger and heavier tanks in the interwar period rapidly left it obsolete.
    These are tanks.
    But tanks are heavy. Really heavy. Even something like the Renault FT could mass around 7 tons and by later standards that would be classified as a tankette (a ‘mini-tank’ as it were); by WWII, medium tanks often clocked in around 30 tons. If you put a vehicle like that on tires, you are going to create a LOT of pressure on those small points of contact. That might still be OK if you are just going to drive on roads and other firm surfaces which can take the pressure. But remember: tanks were designed for the Western Front, which looks like this:

    image-2

    Via Wikipedia, no man’s land in Belgium, 1919.
    This is not a tank.
    Fortunately for the landship committee, this wasn’t a new problem: farming tractors were also heavy and also had to operate in churned up (in this case, plowed) soft soil; the heaviest of these vehicles had much the same problem and the solution was continuous tracks or ‘treads.‘ When kept properly tensioned – tune in, by the by, to Nicholas ‘The Chieftain’ Moran’s YouTube for more than you ever want to know about track tension – the track distributes the weight of the tank across the entire section of the track touching the ground, which reduces the ground pressure at any given point, allowing a big heavy tank to roll over terrain where even a much lighter wheeled vehicle would get stuck.

    This is one of those points where the functionality of a tank (what a tank does) has such a strong influence on design that the design implications of the functionality become part of the definition: a tank has to be heavily armored and has to be able to move off road and as a result has to be tracked, not wheeled. One might be able to imagine some sort of exotic technology that might make it possible to do all of the things a tank does without tracks, but we don’t have that yet.

    The other factor was fire. I’ve mentioned this before, but one of the significant background factors of WWI is that a lot of the belligerents misjudged the kind of artillery they’d need for a general European war. Not to get too deep into the weeds here, but most of the belligerents expected a relatively rapid war of maneuver and so thought that light, direct-fire[efn_note]That is, guns that fire in low arcs towards their targets. The opposite is indirect fire, where the projectile is shot mostly up to fall on the target.[/efn_note] artillery like the famed French ’75 (the Matériel de 75mm Mle 1897) would be the most useful. Those guns could be moved quickly and could deliver a lot of quick firepower on static or moving formations of enemy infantry in support of friendly infantry.

    The problem is that in the conditions of trench warfare, those guns – as they were configured, at least – were far less useful. They were, first off, much shorter in range which meant they had to be brought dangerously far forward to do their direct fire role – often so far forward they could be engaged by enemy rifles and machine guns. This was compounded by the fact that direct fire at range was ineffective against trench works (which are dug down into the earth). But at the same time, the value of rapid firing (because these lighter guns could fire a lot faster than the heavy, indirect fire artillery) direct fire artillery remained high, if only you could get it to the fight.

    Canon_-_Mediatheque_de_larchitecture_et_du_patrimoine_-_APTH001883

    Via Wikimedia, a ‘French 75’ light field gun; the formal name for this fast-firing and deadly light artillery piece was the Matériel de 75mm Mle 1897. Brutally effective in its role, the gun suffered from the fact that trench warfare increasingly prioritized heavy artillery over light, fast moving field guns like this one.
    This is not a tank.
    This was also a problem a tank could solve: as a mobile, armored platform it could move a rapid-firing direct fire gun forward without immediately being knocked out by enemy small arms to support the infantry. There is, I should note, early complexity on this point, with both ‘male’ (heavy direct fire cannon focused) and ‘female’ (machine gun focused) tanks in WWI though in the end ‘hermaphrodite’ designs with both capabilities (but much more focus on the main cannon) triumph, so that’s what we’ll focus on.

    And that gets us the fundamental role structure for tanks: enough armor to resist enemy small arms (but with the understanding that some weapons will always be effective against the tank), enough mobility to cross the churned up battlefield and some direct fire capability to support the infantry crossing it at the same time.

    Comes the Halftrack
    The period between WWI and WWII – the ‘interwar’ period – was a period of broad experimentation with tank design and so by the time we get to WWII there are a number of sub-groupings of tanks. Tanks could be defined by weight or by function. The main issue in both cases was the essential tradeoff between speed, firepower and armor: the heavier you made the armor and the gun[efn_note]Technically here a major issue is also the size of the gun, since a larger gun means a bigger turret, which means a much heavier tank[/efn_note] the heavier and thus slower the tank was. The British thus divided their tank designs between ‘cruiser tanks’ which were faster but lighter and intended to replace cavalry while the ‘infantry tanks’ were intended to do the role that WWI tanks largely had in supporting infantry advances. Other armies divided their tanks between ‘light,’ ‘medium,’ and ‘heavy’ tanks (along with the often designed but rarely deployed ‘super heavy’ tanks).

    What drove the differences in tank development between countries were differences between how each of those countries imagined using their tanks, that is differences in tank doctrine. Now we should be clear here that there were some fundamental commonalities between the major schools of tank thinking: in just about all cases tanks were supposed to support infantry in the offensive by providing armor and direct fire support, including knocking out enemy tanks. Where doctrine differed is exactly how that would be accomplished: France’s doctrine of ‘Methodical Battle’ generally envisaged tanks moving at the speed of mostly foot infantry and being distributed fairly evenly throughout primarily infantry formations. That led to tanks that were fairly slow with limited range but heavily armored, often with just a one-man turret (which was a terrible idea, but the doctrine reasoned you wouldn’t need more in a slow-moving combat environment). Of course this worked poorly in the event.

    More successful maneuver warfare doctrines recognized that the tank needed infantry to perform its intended function (it has to have infantry to support) but that tanks could now move fast enough and coordinate well enough (with radios) that any supporting arms like infantry or artillery needed to move a lot faster than walking speed to keep up. Both German ‘maneuver warfare’ (Bewegungskrieg) and Soviet ‘Deep Operations’ (or ‘Deep Battle’) doctrine saw the value in concentrating their tanks into powerful striking formations that could punch hard and move fast. But tanks alone are very vulnerable and in any event to attack effectively they need things like artillery support or anti-air protection. So it was necessary to find ways to allow those arms to keep up with the tanks (and indeed, a ‘Panzer divsion’ is not only or even mostly made up of tanks!).

    At the most basic level, one could simply put the infantry on trucks or other converted unarmored civilian vehicles, making ‘motorized’ infantry, but as discussed a whole part of the design of tanks is to allow them to go places that conventional civilian vehicles designed for roads cannot and in any event an unarmored truck is a large, vulnerable tempting target on the battlefield.

    The result is the steady emergence of what are sometimes jokingly called ‘battle taxis’ – specialized armored vehicles designed to allow the infantry to keep up with the tanks so that they can continue to be mutually supporting, while being more off-road capable and less vulnerable than a truck. In WWII, these sorts of vehicles were often ‘half-tracks’ – semi-armored, open-topped vehicles with tires on the front wheels and tracks for the back wheels, though the British ‘Universal Carrier’ was fully tracked. Crucially, while these half-tracks might mount a heavy machine gun for defense, providing fire support was not their job; being open-topped made them particularly vulnerable to air-bursting shells and while they were less vulnerable to fire than a truck, they weren’t invulnerable by any means. The intended use was to deposit infantry at the edge of the combat area, which they’d then move through on foot, not to drive straight through the fight.

    image-3

    Via Wikipedia, the US Army’s M3 Half-track (deployed in 1940). You can see how the protection it offers the crew and the passengers is not zero but still relatively minimal: you want to get out of these and move on foot once you are at the fight, since infantry can at least take cover as they move whereas a halftrack is a tempting target for enemy fire.
    These aren’t tanks.
    The particular vulnerability of the open-top design led to the emergence of fully-enclosed armored personnel carriers almost immediately after WWII in the form of vehicles like the M75 Armored Infantry Vehicle (though the later M113 APC was eventually to be far more common) and the Soviet BTRs (“Bronetransporter” or “armored transport”), beginning with the BTR-40; Soviet BTRs tended to be wheeled whereas American APCs tend to be tracked something that also goes for their IFVs (discussed below). These vehicles often look to a journalist or the lay observer like a tank, but they do not function like tanks.[efn_note]At least not against well-armed enemies. it is worth noting that, when fighting against enemies who lack access to effective heavy weapons and also don’t have any armored platforms of their own that would require something more powerful than a heavy machinegun.[/efn_note] The M113 APC, for instance, has just about 1.7 inches of aluminum-alloy armor, compared to the almost four inches of much heavier steel armor on the contemporary M60 ‘Patton’ Tank. So while these vehicles are armored, they are not intended to stick in the fight and are vulnerable to much lighter munitions than contemporary tank would be.

    image-4

    Via Wikipedia, a Soviet BTR-152, developed in 1949 and deployed in 1950. Note while fully enclosed, the purpose of this vehicle is transport, not fighting.
    This is not a tank.
    At the same time, it wasn’t just the infantry that needed to be able to keep up: these powerful striking units (German Panzer divisions, Soviet mechanized corps or US armored divisions, etc.) needed to be able to also bring their heavy weaponry with them. At the start of WWII, artillery, anti-tank guns and anti-air artillery remained almost entirely ‘towed’ artillery – that is, it was pulled into position by a truck (or frequently in this period still by horses) and emplaced (‘unlimbered’) to be fired. Such systems couldn’t really keep up with the tanks they needed to support and so we see those weapons also get mechanized into self-propelled artillery and anti-air (and for some armies, tank destroyers, although the tank eventually usurps this role entirely).

    Self-propelled platforms proved to have another advantage that became a lot more important over time: they could fire and then immediately reposition. Whereas a conventional howitzer has to be towed into position, unlimbered, set up, loaded, fired, then limbered again before it can move, something like the M7 Priest can drive itself into position, fire almost immediately and then immediately move. This maneuver, called ‘shoot-and-scoot’ (or, more boringly, ‘fire-and-displace’) enables artillery to avoid counter-battery fire (when an army tries to shut down enemy artillery by returning fire with its own artillery). As Artillery got more accurate and especially with the advent of anti-artillery radars, being able to shoot-and-scoot became essential.

    image-5

    Via Wikipedia, an M7-Priest self-propelled gun. Note that whereas a tank essentially took up much of the role of direct fire artillery, self-propelled artillery generally takes up the role of indirect fire artillery.
    This is not a tank.
    Now while self-propelled platforms were tracked (indeed, often using the same chassis as the tanks they supported), they’re not tanks. They’re designed primarily for indirect fire (there is, of course, a sidebar to be written here on German ‘assault guns’ – Sturmgeschütz and their awkward place in this typology, but let’s keep it simple), that is firing at a high arc from long range where the shell practically falls on the target and thus are expected to be operating well behind the lines. Consequently, their armor is generally much thinner because they’re not designed to be tanks, but to play the same role that towed artillery (or anti-air, or rocket artillery, etc.) would have, only with more mobility.

    So by the end of WWII, we have both tanks of various weight-classes, along with a number of tank-like objects (APCs, self-propelled artillery and anti-air) which are not tanks but are instead meant to allow their various arms to keep up with the tanks as part of a combined arms package.

    MBTs and IFVs
    As we get into the Cold War era, one thing becomes simpler: the distinction between different kinds of tanks (heavy, medium, light, cruiser, infantry, etc) largely[efn_note]With some exceptions[/efn_note] drops away. Improved engines, suspension and lighter but more effective composite armor meant that the slightly different roles of the different weights of tank could increasingly be accomplished by a single platform evolving out of late-war medium tanks. You could now fit a heavy tank’s gun and armor on a chassis with a medium tank’s speed and maneuverability. The first of these ‘universal’ tanks was the British Centurion (first deployed in 1946)[efn_note]You really feel for the British, whose tank designs during WWII often left a lot to be desired and it is only as the war is basically over that they stumble on one of the best tank designs ever in Centurion.[/efn_note] and other countries followed suit.

    image-6

    Via Wikipedia, Centurion, the world’s first main battle tank, having a favorable mix of armor, speed and firepower in a single platform.
    This is a tank.
    The result is the modern ‘main battle tank’ (MBT), typically between 45 and 75 tons, with a single powerful direct-fire cannon as its primary armament. That’s not to say design differences between militaries drop away; there are still decisions to be made: the level of emphasis between speed, armor and firepower for instance. Another major decision is whether a tank is designed with a three-person turret (one of whom is a dedicated loader) or a two-person turret with an autoloader (that is, a machine that does the loading for you). It used to be that now I’d have to go on about why going autoloaders aren’t simply obviously the best but given the live demonstrations of some of the drawbacks of Soviet/Russian carousel autoloaders going on right now I’ll just say that both options have advantages and drawbacks and move on. So there is variety within the idea of an MBT, but by and large most countries field just one type of MBT (or one family of MBTs for countries which can’t afford to retire older systems) and that covers their tank needs.

    image-7

    From Rob Lee’s twitter feed, a destroyed Russian T-72B3 with the turret having been blown off. This happens because the ammunition in the carousel autoloader ‘cooks off’ when the body of the tank is struck and penetrated by enemy fire. The structure of an autoloader makes keeping ammunition secure and channeling any ammunition explosion to the outside of the tank more difficult, but the carousel autoloader design of the T-72, T-80 and T-90 tanks is particularly poor at this. Crew survivability in these cases is extremely low.
    This was a tank.
    But of course nothing could easy so just as tanks were getting easier to keep track of, APCs get much more complicated. Even before they were fully enclosed, APCs had generally carried some kind of defensive weapon (usually a heavy machine gun), but you weren’t supposed to fight with it if you could avoid it. Beginning in the 1950s, designers – first in West Germany – began experimenting with the idea that an APC could be armed to not merely deliver the infantry (‘dismounts’) but to actually fight when they got there. The thing is, there are a lot of situations where an infantry formation might want more firepower but where a tank would be overkill: armored vehicles lighter than tanks, or enemies with lighter fortifications, for instance. West Germany pioneered the idea by putting a 20mm autocannon on their APC, the Schützenpanzer Lang HS.30, enabling it to put out some meaningful firepower, albeit much less than a tank.

    image-8

    Via Wikipedia, a Schützenpanzer Lang HS.30 currently in the German Tank Museum. As you can see, it is still mostly an APC, with the turret not being the main focus of the design, but nevertheless offering substantial firepower.
    Despite its location, this is not a tank.
    The USSR cottoned on to the idea and liked it, resulting in the Soviet BMP-1 and the subsequent BMP family of what we call ‘infantry fighting vehicles’ (IFV). Initially resistant to the idea (American doctrine was that APCs move troops and should not fight if they could help it), the United States, noticing the effectiveness of these sorts of platforms, got into the act with the Bradley Fighting Vehicle (these days the M3 Bradley). And IFVs, especially the Bradley, look like tanks. And indeed, they are sometimes called on to do the kind of armored reconnaissance and infantry support jobs that in a previous era would have gone to a light tank.

    image-9

    Via Wikipedia, a BMP-3, prominently displaying both its main armament and the All-Purpose Soviet Log attachment (The USSR may be gone, but the All-Purpose Soviet Log survives!). You can see the evolution in design: greater emphasis on the weapon, but this is still primarily a troop transporter with a lot of internal space for the purpose.
    This is not a tank.
    But they are also notably not tanks in several key ways. The primary job of an IFV is to move infantry and support them against lighter targets; some IFVs do maintain some kind of anti-tank capability, but it tends to be more limited (e.g. the Bradley’s pair of TOW AT missiles). The requirement that an IFV needs to be fairly fast but also needs to fit a bunch of dismounts means they can’t carry the firepower or the armor of a tank, often using lighter aluminum armor rather than steel or heavy composites. Finally, the tendency is for IFVs to mount lighter primarily armaments – again, space and weight concerns – like the Bradley’s 25mm M242 Bushmaster chain gun. The BMP-3 is probably the most heavily armored IFV out there with a low-velocity 100mm rifled gun and a 30mm autocannon, which is still a far cry from the firepower of the high-velocity 125mm main gun of a contemporary T-80 or the 120mm high velocity gun of a M1A1 Abrams. Instead, most IFVs would rely on anti-tank missile systems to engage tanks (although IFV autocannons can cause a tank serious problems if they can engage the rear or side armor, which is thinner).

    image-10

    Via Wikipedia, the Bradley (in this case, M3), probably the single worst not-a-tank offender for its appearance. One thing that confuses people in this is scale: the Bradley is taller than the Abrams (just about 10ft to 8ft), so it is easy to mistake the proportions. Moreover that height also goes towards the design consideration: tanks, because of their offensive role, need to have lower profiles so they can fire and then hide behind things (‘turret down’ or ‘hull down’ position); the Bradley’s role is different – it has to fit a bunch of dismounts – and so it ended up a lot taller.
    This is not a tank.
    Note that the IFV did not mean the end of the APC just as the APC didn’t bring the end of soft-skinned troop transports. In the US military, the Bradley serves alongside lighter-but-still-IFV Strykers, the venerable M113 APC along with soft-skinned HMMWV (Humvees; to be in theory replaced with the Oshkosh[efn_note]B’gosh[/efn_note] L-ATV) and trucks of various kinds and uses. Likewise, the Russian army has its BMPs (which are IFVs), and BTRs (which are APCs) as well as soft-skinned vehicles – or at least it did until, I am now being told, they were all towed away by Ukrainian farmers. The real Iron Harvest.

    The final category worth noting here are variations on the concept of the MRAP (Mine-Resistant, Ambush-Protected): infantry transport vehicles designed to resist the sort of dangers one encounters in counter-insurgency operations, mostly mines, IEDs and small-arms ambushes. In essence, these vehicles are a purpose-built version of the up-armored Humvees designed to operate in a very particular combat environment (insurgencies and particularly urban insurgencies). These sort of vehicles have gotten more visibility in the United States because many of them have been shifted into the hands of law enforcement, where their utility is questionable, to say the least.

    image-12

    Via Wikipedia, a set of Caiman MRAPs deployed in Iraq. I actually use this vehicle when talking to my students to talk about trade-offs in the kind of conflicts a force prepares to fight, because the improvements that make an MRAP safer in an urban insurgency would render it much less viable in a large-scale conventional conflict than thinner-skinned, less well armored (but lower profile and faster) vehicles.
    These are not tanks.
    So What is a Tank?
    In many ways, the role a tank fills hasn’t changed much since WWII when ‘engage other tanks’ was added to its list of jobs: tanks provide offensive ‘punch’ and firepower to allow infantry to advance, seize ground and maneuver in an environment where, thanks to machine guns, even small enemy forces can put out a lot of bullets to otherwise prevent infantry from doing those things. Tanks also need to engage other armored vehicles and potentially fortified positions. Doing those two jobs require that tanks heave the heaviest armor and the heaviest main gun possible, which both precludes them doing other things (like moving infantry) while at the same time demanding that they be tracked in order to manage the weight of that stuff.

    I don’t think a tank needs to have a turret, by this definition, to be a tank, but most tanks have turrets. But many non-tanks also have turrets. The key here is role and function, not any particular design element.

    image-11

    Via Wikipedia, the Swedish Stridsvagn 103 or ‘S-tank’ (in service from 1967 to 1997) is a rare example of a turretless tank, though it is worth noting that Sweden’s later tanks are turreted.
    This is a tank.
    What has changed is that tanks have gone from being effectively the only armored vehicle on the battlefield to working in concert with many other armored fighting vehicles, which have different roles. IFVs, in particular, can blur the line a bit between a tank and an APC, but in most cases the differences in design, firepower and thus capabilities between a tank and an IFV is massive; attempting to use IFVs like tanks is a good way to lose a lot of IFVs.

    Is the tank on the way out? I don’t think so. Nicholas ‘The Chieftain’ Moran did a fairly good overview of the question, but the key point here is that the design of the tank is dictated by its battlefield function and there still isn’t anything out there that does a tank’s job better than a tank does; IFVs and other AFVs have to make pretty clear compromises in armor protection and firepower to accomplish their main roles. And while the public may be discovering the vulnerability of the tank for the first time, tanks have always been vulnerable to a wide variety of threats and have always required supporting arms to mitigate (but not remove) that vulnerability.

    Now does it matter that the general public cannot tell the difference between a tank and an IFV? No, it probably doesn’t, to be honest. But it does matter that journalists covering wars and politicians making decisions about them also don’t seem to be able to, because it hints at a broader gap in the base of knowledge they are working with. “Bradley/BMP-3 isn’t a tank, but something else (an IFV) with a different function and purpose” is a fairly entry-level piece of information about modern warfare. And at some points that information gap can be abused, as when the German ambassador to the United States described Germany sending ‘Gepard Tanks’ to Ukraine:

    Presumably Emily Haber was attempting to avoid a truer description of the event which would have been, “Germany is sending largely obsolete self-propelled anti-air platforms, the Flakpanzer Gepard, to Ukraine.” A journalist who is actually qualified to be covering a modern conflict ought to immediately be able to call this out as, at best, an unfortunate mistake (if not an intentional error). But journalists often sadly lack that kind of domain-specific knowledge, which really hurts their ability to inform the public.

    In any case, here is the terminology shorthand: any armored fighting vehicle is an ‘armored fighting vehicle’ (AFV – convenient, huh?); that includes tanks, but also self-propelled artillery and self-propelled anti-air, IFVs, MRAPs and APCs. A tank is an AFV whose purpose is to offer powerful direct fire capabilities against a range of enemy targets (infantry, buildings, other tanks and other AFVs); tracks, while not a dead giveaway are good to look for. Not all tracked AFVs are tanks, but all tanks are tracked AFVs because of the demands that the weight armor and firepower place on them. If you take an APC and put big gun on it, it becomes an IFV, not a tank. If you take a truck and put a big gun on it, it becomes a technical, not a tank (but that’s a story for another post).

    This post is not a tank.

    1920px-Mounted_Soldier_System_MSS

    This, however, is a tank.
    Edit: Turning the Post off and on again.

  12. I’m almost surprised you didn’t take the time to leave a footnote snarking at Pentagon Wars when you mentioned the Bradley.

    (Though I suppose it’s not particularly germane to the topic at hand)

    1. It was my first thought even before he got to the Bradley. Obviously, the film is pop culture military history but I’d be curious to hear from Bret about any accuracy

        1. So … from an Armor guy who both served on and has been involved in the development of Bradley as well as a number of other US armored systems.

          The actual book Pentagon Wars is a great read, though you have to keep in mind that it is from the point of view of an Operational Tester. I know folks involved in the program at the time who have choice things to say about Col Burton and he did some fairly boneheaded things related to Bradley that don’t make the movie. And he saves some of his more choice skewering for Air Force programs.

          The fascinating thing about the movie, though, is that after you strip away much of the dramatization and comedy, it’s remarkably historically accurate to events (there’s literally only one scene in it that did not actually happen, even if timelines and circumstances for others have been tweaked to fit the medium — and sadly no, it’s not a scene that has anything to do with sheep). However, what’s missing if the full context to the movie, which makes the various events much less sinister, and the fundamental conflict in the real world was about approach to testing, not the need for realistic teating.

  13. Bret, I wish I could find it again, I can’t; but somewhere I saw a cartoon that perfectly illustrated the “mission creep” of armored troop transports: 1. Foot infantry can’t keep up with tanks. 2. So they follow in trucks, but those are too vulnerable. 3. So they try half-tracks; but those are still too vulnerable. 4. So they have fully covered APCs; but they end up needing some basic counter-attack capability. 5. So they add a heavy machine gun and maybe a rocket launcher. 6. And then at least a medium artillery piece, so now they have an IFV. 7. Which needs more room inside for ammo, so the crew ride on the outside. 8. Where they’re too vulnerable, so they dismount and spread out. 9. And now they’re foot infantry following a tank again.

    1. I mean. Isn’t Step 7 idiotic?

      Because that really stands out to me. Steps one through six are totally sensible, but then suddenly you get to step 7 and with no warning you’ve gone from zero to fucking nuts. There’s no “creep,” just a sudden leap into the abyss.

        1. Why does the APC need heavy guns when it’s right next to a tank with heavy guns?

          1. Because usually it’s not right next to a tank with heavy guns – it’s *might* be in a larger unit that includes tanks (but even those often aren’t right next to it) or it may well be in a non-tank unit at all.

            So it’s quite likely that after delivering the troops it’s the strongest firepower in sight – it doesn’t have the staying power of a proper tank, but if circumstances allow it’s very useful for it to stick around and provide fire support to the dismounted troops.

    2. The more things change, the more things stay the same. May I introduce Early Modern era mounted artillery and dragoons (mounted infantry)? It used to be a problem that the operational mobility of infantry (marching on foot) and artillery (most of the gun crews marching on foot, along the pieces towed at a slow pace by horses) couldn’t keep up with cavalry. Hence dragoons: find the cheapest “minimum viable horse”, tell the infantryman (musketeer) to ride around it when not fighting, then dismount to shoot. Likewise, put the gun crews on horseback, and slap extra horses before the guns so that they can tow them at a decent clip.

      The evolution of AFVs is the same. Invent the general concept of self-propelled operational mobility, and start ticking the boxes. Infantry (support) guns (+ AT guns). The infantry itself. AA. Artillery. Recon/spotting, both for command and the indirect-fire artillery.

      But to the extent you are poor and/or expect not to need everything to be this mobile, you can in parallel keep the foot-march speed combined arms forces. Alternatively, you might invent other forms of operational mobility (e.g. air insertion, where the first box ticked was infantry using parachutes, or gliders, or helicopters) and you have to start developing compatible ways to provide them with AA, artillery, etc. (see WW2 heavy gliders). Or you might say instead that you’ll just have total air superiority, your airmobile infantry will use tactical air support in lieu of artillery/AA/AT/recon while you can cobble together an infantry support gun.

      Also note an inherent “problem” with IFVs. If, to be combat-effective, the infantry needs to dismount, suddenly the operational mobility _when engaged_ is both “vulnerable to artillery blanketing the area with VT-fuzed shrapnel” and slow. Just as early modern dragoons eventually ended up saying “never mind” to the part where they were supposed to dismount, and just used a shorter firearm (a carbine) to shoot from horseback, it would be awesome if the infantry could do its uniquely infantry things while still mounted in a vehicle with enough armor to ignore shrapnel (and probably bullets) and good cross-country mobility.

      1. Pretty sure that’s called power armor. “Uniquely infantry things” involves stuff like entering buildlings and so on, which sort of excludes vehicles.

        1. Yes, the things that humans fight over, tend to be things that are designed by and for humans and thus scaled for humans. So the closer you get to the objective, the more you find that you’re trying to go places where nothing much bigger than a human can fit (or avoid crashing through the floor).

          And even during the approach, if you come in overwhelming force the enemy will likely try to hide and let you pass, so they can hit you in the flank or tear up your supply lines. Any place that isn’t a desert or prairie, they can probably find places to hide that are appropriately human-sized.

          If you want to get the enemy out of those places, or even just know for sure whether they’re in there, you need a versatile autonomous combat element that’s no bigger than a human. And, sorry Daleks, one capable of negotiating staircases and turning doorknobs.

          Sitting in the back of a BMP poking your Kalashnikov out the firing port and shouting “I’m infantry!”, doesn’t make you infantry.

          1. That’s where the joke about genetically-modified velociraptors comes in. And a pile of other harebrained schemes to avoid paying the butcher’s bill. Like training dogs with explosive packs on their backs to run under tanks to blow them up …

          2. the trick is fighting with the armour and dis or mout when appropiate

          3. Pedantic correction, Daleks in the new Dr Who can cope with staircases and doorknobs.

            Checking the history … 25 years to put in service the levitation upgrade (Remembrance of the Daleks), another 17 years for the manipulator that can manipulate things that aren’t round (Dalek). Procurement programs for the most ruthlessly militaristic species in the galaxy/universe don’t seem to run any faster than they do here on Earth 🙂

          4. I’m pretty sure a Dalek would cope with a doorknob by blowing up the door.

          5. In the very first Dalek story we see a Dalek pick up a piece of paper with its manipulator; and somehow they built a technological civilization. So I’m pretty sure it was just that the BBC’s special effects budget didn’t permit showing the dexterity of the “plungers” until recently.

          6. They inherit a civilization. They were, regardless of what version you choose, the product of a highly technological society that made them because of a war.

        2. Or like when the overpowered and underbrained ED-209 couldn’t follow Robocop down a flight of stairs.

        3. Umm no, uniquely infantry things involves cover and concealment, assaulting and defending prepared fortified positions. It’s not all insurgencies, all the time. Sometimes there’s an actual army on the other side.

      2. There’s been some experimentation with fire ports: hatches in the sides of armored transports for the infantry to stick their guns out of. Last I’d heard, they were hard to shoot out of with any accuracy, so they mostly resulted in wasted ammo

        1. Yes, if you’ve got infantry fighting from inside an IFV, probably at least 80% of the effective antipersonnel capability comes from the gyrostabilized turret-mounted machine gun with the fancy sights and the commander/gunner team. Letting people shoot their rifles through firing ports makes them feel like they are helping rather than just being targets in a thinly-armored box, but they’re not really helping that much and I think most armies have plated them over. There don’t seem to be any on the BMP-3 Brett shows, though they were conspicuous on the original BMP-1.

          If you’re riding an IFV or an APC, you’re a target in a thinly-armored box until you dismount. Beats being a target in an unarmored truck, which is something at least.

      3. > “to be combat-effective, the infantry needs to dismount, suddenly the operational mobility _when engaged_ is both “vulnerable to artillery blanketing the area with VT-fuzed shrapnel” and slow”

        Isn’t the point about infantry that they can use cover and concealment, like, really well? Whereas anything is vulnerable to arty if spotted in the open.

        Also, isn’t the point about modern combat that attacking non-suicidally is inherently slow? Tanks are fast after a penetration, when they’re rolling through open country behind enemy lines. Nothing is fast while attacking through prepared positions.

        1. “Anything is vulnerable to arty if spotted in the open”, but to extremely varying degrees. If it’s a “soft” target (trucks, dismounted infantry, etc.) then the artillery putting a shell anywhere within, say, 50 meters (150′) is at least a mission kill. (By which I don’t mean any particular casualty rate, but the unit losing the race against reinforcements, “the race against the train” in WW1. A tank with a thrown track, which can be repaired in an hour, is still a mission kill.) Whereas to incapacitate vehicles deliberately armored against shrapnel, the shell needs to land within, say, 5 meters. 10x radius, 100x target area, so the artillery either needs to throw 100x as many shells, or use guided munitions, or operate in direct-fire mode (as an AT gun). Protection from indirect-fire artillery is the primary reason to armor things — including infantry, see the introduction of helmets and occasionally torso protection during/since WW1.

          The point about infantry is to a large extent recon, as John Schilling points out above. Spot the enemy, even if they try to use cover/concealment, and do something about it — with their own firepower, or by calling for something heavier.

          The third paragraph is exactly my point. [b]Currently[/b] it happens to be the case that, for attacks to be non-suicidal, they need the infantry to walk ahead and thus prevent the enemy from ambushing anything other than the infantry, even if everything else in the combined-arms unit had the ability to move much faster and engage targets at that pace. Only after the area becomes clear enough for the infantry to mount can the entire unit speed up. [i]In the future[/i] it may become the case that, [i]at least in some kinds of terrain,[/i] something can replace dismounted infantry as the eyes of an advancing force.

          As an exercise in imagination: a smallish (1m wingspan) drone, flying ahead of the armored ground units in large numbers (for simplicity, imagine 1:1 for foot infantry) and reporting/illuminating targets for engagement by the ground vehicles, thus letting the infantry stay mounted and thus the whole combined-arms unit attack through the enemy line at the speed the vehicles can roll through the terrain. While doing so, they can mostly ignore indirect-fire artillery (particularly if they have something to take care of guided munitions; active-defense system possibly hooked into drones for improved lookout, thicker top armor, &c). Oh and add another type of vehicle, the drone tender/carrier, to the force (or fold the functionality into an existing vehicle, such as the IFV). And of course in a symmetric fight, the defender will likewise have drones and anti-drone systems (from something as simple as the indirect-fire artillery setting a high bursting altitude on their shells and shooting an aerial barrage — interwar AA style) and anti-anti-drone systems/procedures (e.g. always keeping drones dispersed in frontage, depth, altitude, and keeping reserves inside the tender/carrier). Currently these parts remain to be shaked out, our situation is like (early-) interwar doctrine about planes and tanks, in retrospect what I’ve written here will look hilariously wrong.

          1. @Basil Marte

            >”for attacks to be non-suicidal, they need the infantry to walk ahead and thus prevent the enemy from ambushing anything other than the infantry”

            I really don’t think sending infantry walking into prepared enemy positions is how armies attack, at all. My source is basically any book about military matters. The first that comes to mind is “Military Power – Explaining Victory and Defeat in Modern Battle” by Stephen Biddle, also recommended by our host.

            >”As an exercise in imagination: a smallish (1m wingspan) drone, flying ahead of the armored ground units in large numbers (for simplicity, imagine 1:1 for foot infantry) and reporting/illuminating targets for engagement by the ground vehicles”

            Doesn’t seem very plausible, to be honest. If the tankers are lucky, the drones will get wiped out as soon as they take to the air. If not, it’s a big red target marker for anything that can shoot anti-tank mines and/or ordnance.

            Also, again, I don’t think that’s how infantry and armor operate.

          2. The infantry are mainly there to find the anti-tank weapons before they can fire on the tank. They’re particularly there to find people with RPGs that need to fire at a tank’s side armor to penetrate. If there’s a proper prepared position with a machine gun, that’s where the tank or artillery or air support comes in.

            As for the drones, yes, people will shoot at them. They’ll also shoot at screening infantry. But when you shoot one drone, you’ve given away your position to the other drones and the tanks will shoot you. And people will know there’s tanks nearby when they see the drone, but they’ll also know there’s tanks nearby when they see the tanks, and the drones can let the tanks see them.

          3. One more note.

            > “If it’s a “soft” target (trucks, dismounted infantry, etc.) then the artillery putting a shell anywhere within, say, 50 meters (150′) is at least a mission kill.”

            Trucks yes, infantry no. Not if it’s behind a meter of soil or two. Infantry is expert at not being spotted and at taking cover. While tanks can do so too, to an extent, it takes much greater time and effort.

  14. As a minor correction, the M2 Bradley is the US Army’s IFV. It’s the same fundamental design of the M3 Bradley, but the M3 is the cavalry scout version- it has the troop compartment ripped out and replaced with more ammo(in particular more missiles) and more radio equipment.

    1. Not ripped out but seating space was reduced to 2 (later 3) in order to carry more ammunition.

      And the M3 has left service — M2 configurations are now used in the cavalry role as well. Turns out that much ammo wasn’t needed and occasionally being able to carry more soldiers is useful.

      As a former M3 commander who wondered if it was wise to sit on a fuel tank with another fuel tank to my right, a magazine of cannon ammunition in front of my knees, a magazine of machine gun ammo by my head, and a rack of twelve ATGMs behind my ass … I approve.

  15. I am disappoint that I got through this entire article without looking at a single picture of either an Adeptus Astartes Mars Pattern Rhino chassis, or of a Bonaparte police tank.

        1. Sure, but that’s like the self-propelled artillery using the same chassis as a tank. I’d think the Land Raider claim is more controversial, though to my mind it is very much a tank and not an IFV, even though it has excellent troop transport capability.

          1. I’d say it’s an IFV gone down the path of tankhood. Deploying infantry is literally central to its design; it has only a heavy bolter facing forwards while relegating its lascannons to the sides to make room for a forward assault ramp. It’s gone so far with adding armor and heavy weapons that it’s become a viable tank, but the design prioritizes the terminator team.

          2. Better question; even if the stock Land Raider Phobos is a tank, which is in doubt, is the Land Raider Crusader, which completely strips the heavy lascannon armament for weapons whose purpose is 100% to support its mission as a Terminator delivery system, also a tank?

          3. Well, it’s still got the armor, and it’s got a multi-melta, so the Crusader pattern is perfectly capable of taking on other tanks, and needn’t be relegated to a support role. Still a tank.

          4. I suppose that depends on if definitions are exclusive; I’d rate the Crusader pattern especially as a very heavy IFV. While it’s got the multi-melta it’s specifically intended to drive infantry into combat and provide them with fire support and the multi-melta is intended to shoot holes in fortifications for infantry to move through.

            I’d probably rate the Eldar Falcon as a tank with troop capacity, though; the heavy guns are more central to its design. Of course, it’d lose a stand-up fight with a Land Raider, but then again its infantry complement probably isn’t beating five Terminators.

            I’d say the Land Raider has gotten forced into serving as a tank for the Astartes for historical, logistical, and religious reasons. In the Great Crusade era any expeditionary fleet would have a complement of heavy Imperial Army tanks like Malacadors, but post-Crusade cooperation is at best fraught. The Land Raider chassis is solid enough this works okay, and the machine spirits would disapprove of mounting a heavy cannon centerline in preference to terminator capacity.

          5. I suppose, but I’d argue that using a Land Raider Crusader for anything other than delivering troops is probably a gross misuse of resources. Deploying it as a tank on the grounds of “it has a multi-melta” seems dubious at best.

            And of course an LRC with the storm bolter up top has NO claim to be a proper tank, I reckon.

          6. I would say that the main reason to use an LRC and to a lesser extent a standard Land Raider as a tank is that you currently have an LRC and your infantry are either occupied or unsuited to the tactical situation.

            Since chapters have limited armor pools, only a limited portion of which is deployed to a given planet, and in many cases their authority over and trust in avalible IG forces is questionable at best, this can be a pretty compelling reason.

          7. And yet, both versions of the Land Raider are at least as good and arguably better than anything else the Imperium has in fulfilling a tank role at its size, without considering the infantry complement (possibly depending on your current version of the ruleset). If you take ‘points value’ as a stand-in for ‘logistical cost’, they’re not as efficient in that role, but that’s a diffeent question. The one reason I’d consider not regarding the Crusader a full tank it’s it’s not as useful in a drag-out fight with, say, a Baneblade or a titan.

          8. The current Paladin model (A7? Maybe the A6) uses a “Bradley-Derived” hull according to Wikipedia.
            If you count the Stryker MGS as a tank; or the one that’s got Javelins in its CROWS, then the Stryker is sometimes maybe a tank

        2. A Rhino chassis can become a tank, though; the Predator varient pretty clearly qualifies.

          See, this sub-thread is precisely why I brought it up. A Predator IS a Rhino, in the same way a Whirlwind or a Vindicator are. They’re all Rhinos!

          1. That’s not unusual even IRL though. There were tank chassis that were used both for self-propelled artillery, anti-air, tank-destroyer and “proper” tank roles.

          2. But is a Vindicator a tank?

            For the record the Lexicanum wiki calls it a “siege tank”.

            Bonus round: Is a Carnifex a tank?

          3. Hot take: Carnifexes are cavalry. (Though my understanding is there are newfangled ones with a versatile enough loadout they could possibly be considered tanks.)

          4. @guy I’d say yes, a Carnifex is a tank. And if they’re still anything like they were in 5th ed, eldar Vypers are Hiluxes with a machine gun strapped to the back. Not a tank. By any measure.

          5. The Eldar thing I was referring to is the Falcon Grav Tank. It’s got two turreted heavy guns and what constitutes heavy armor for Eldar.

    1. The M113 APC, which pretty clearly inspired the Rhino, was mentioned. (funny how a company that is so aggressive about IP took so many of its ideas from elsewhere)

  16. One thing missing from this is an answer to the “so why should I care?” question. My stock answer is to look at it from the victim’s point of view.

    If you encounter an enemy tank on the battlefield, you are probably going to have a bad day. You may survive or even prevail, but the enemy came to kill you, up close and personal, and they brought a beast designed for that purpose alone.

    If you encounter a not-tank vehicle on the battlefield, that’s a support vehicle of some sort and you have to look for what it’s supporting to know what kind of day you are going to have. If there’s nothing else, then it’s probably the enemy that is going to have a bad day because they probably didn’t plan on having their support vehicles going into battle alone and you may be able to score some cheap kills.

    Modulo Brett’s point 3 about using APCs/IFVs as impromptu light tanks against people with no antiarmor capability, of course. But an IFV without infantry to support usually means the enemy should have brought a tank and may regret that mistake.

    And if you’re just watching from a safe distance trying to assess strength and capabilities, counting actual tanks can be a fair way to do that because tanks are major elements of an army’s battlefield strength in their own right. Support vehicles only count if they have something to support, and you can’t reliably infer than from just the number of APCs or whatever – different armies will have different support ratios.

    1. Honrstly i would habe preferred facing a tank over an IFV, the armament would make little difference for a REMF, the infantry squad is a very different beast

      1. Well, yes. If you see an IFV, look for the infantry squad it is supporting – *that’s* what’s going to give you a bad day, flushing you out of wherever you’re trying to hide. If there isn’t an infantry squad (or if it’s unwilling to dismount), see if you can scrounge up an old M-72 or RPG or whatever, and make them wish they’d brought a real tank.

    2. Hopefully if I’m ever in a situation where I can expect to be facing any kind of gun-equipped vehicle, I’ve got better training that a history professor’s blog to go off on recognizing the threat.

      OGH says at the very end why you should care: technically, unless you’re a legislator or world leader or reporter, you really don’t need to care. But those people should very much care about the differences because they are crucial to understanding what the vehicles are intended to do and what they need.

  17. Personal version of “what I think of as a tank” having absorbed a similar definition of “vehicle with a big gun, meant to fight up close and have enough armor to survive doing so, that can move smoothly and quickly for its time”:

    Real Vehicles:

    -Tank Destroyer/Assault Gun/etc.: If I hadn’t heard that these were considered something different, I’d think of them as specialized tanks.
    -Wheeled vehicles with big guns: This thing and similar vehicles to me probably count, or I’d think of them as mini tanks, though possibly don’t have the armor to quite fit, and I’m not sure how many there are. Wheeled or tracked the big thing is “can move quickly/handle most terrain”, which as far as I know they can.
    -Maus or other really big things: Described as really slow and might well count for that reason. Really large and slow things are a different category for me, though I’m not sure what I’d call them. (British WW! tanks are still included. both grandfathered in, and for the technology of the time they moved about as fast as they could, and no description I’ve heard says they slowed down attacks when everything else could have moved faster, though I may be remembering wrong or they did and what I heard left it out.)
    -Self propelled artillery, anti air, etc.: I’ve absorbed what this post is talking about from other people, so mentally leave these out.

    Fictional Veicles:

    -Civilization series:
    –“Armor” or “Tank” units in civ type games are obviously meant to represent tanks, so count. Or as likely, tank heavy units with some support stuff.
    –“Fusion Tank” from Call to Power, Hovertanks from SMAC/Alpha Centauri: Hovertanks, if they existed and worked, could move quickly, and usually have the big guns and armor, so would be included.
    –Leviathan from Call to Power: Too big and slow, goes in the “huge and slow” category described.
    –Speeders with lots of armor, Alpha Centauri: In theory these would count, though in practice I’ve never designed such a thing. (Weird game mechanics reasons, very short version is the combat system is very abstracted and doesn’t really represent how actual things would be designed.)

    -Starcraft Series:
    –Siege tanks: A weird one. Clearly meant to represent a vehicle that could act as artillery or a tank, but in game the artillery is the much more common use, plus the units isn’t all that tough for its cost. Game mechanics don’t really represent well what tanks seem to to anyway. I think of this as 1/4 tank 3/4 self propelled gun with longer setup time.
    –Thor: Goes in the “really huge vehicle’ category above, though would probably fill a tank like role if all of this was real.
    –Ultralisk: Honorary tank, is about as close as zerg could get. Probably would fill a similar role if it existed of “tough/heavily armored thing that attacks big threats to help the smaller guys fighting with it”. Only way to get closer would be if it spit acid/spines/other zerg bio ranged attacks.
    –Immortal: I think of walking machines as different, though this probably won’t ever come up in real life. Does fill a similar role.
    –Dragoon, maybe Stalker: In game these fill a similar role as ranged infantry of the other species so I don’t think of them as tanks. Though with many other armies could probably fill the role.

    The point of this is….not sure, honestly. Maybe an interesting thinking exercise.

    1. Hover tanks in OGRE and Traveller seem to me to be recreating the “light tank” role, in that they gain very high speed by sacrificing armour. They usually have enough firepower to destroy at least some heavily armoured vehicles or bunkers.

      To some extent this is a limit of the technology. Hovercraft stay above the ground by blasting air downwards at higher pressure, but to carry more weight, you have to increase the pressure, which also increases the temperature due to inconvenient physics. A hover tank with really heavy armour or really heavy gun would end up as effectively a very low flying jet engine. And we know from the Harrier and F-35B VTOL aircraft that those do bad things to the surface underneath them.

      Once we get to antigrav vehicles, those can be stacked with as much armour as you like. At which point you are back to the main battle tank, a heavily armoured off-road vehicle with big gun. The antigrav replaces the tracks, but the doctrine and battlefield purpose are the same.

      1. > ” you have to increase the pressure, which also increases the temperature due to inconvenient physics”

        Wait, why? PV=nRT, to multiply P you multiply n. A hover craft’s skirt is an open system, not a balloon. It’s not trying to increase the pressure of a given, constant quantity of gas, instead it’s pumping in lots of gas from the outside, thus high pressure at low temperature.

        Now, correct me if I got my math wrong, but 2 atm of pressure under a 25 sqm skirt will support about 250 tons. That’s the surface area of one Abrams tank, supporting the mass of about four. Would that really be such a big deal, for most surfaces?

        1. Depends how the air gets compressed. If too quickly, it does heat up, though I’m not sure how much.

          As for whether it damages anything….the computer game examples I used don’t ask that question or assume antigravity. In real life I can’t say much, blast pressures and wind pressures I know are surprisingly low, but hot that translates to hovercraft air pushing from all directions not so sure of.

        2. I’m not very familiar with hovercraft, but if it’s being held up by pressure underneath (rather than the equal-and-opposite reaction from the air being blown downwards) then it’d need to have a localized overpressurized region compared to ambient atmospheric pressure to provide a lifting force. It’s an open system yes, but it’s like blowing into a balloon with a hole that’s simultaneously letting the air out, so you have to keep blowing it in as fast as it escapes to keep the balloon inflated. The faster you blow in, the more the pressure increases and the faster the air escapes, so the pressurized air inside would presumably also heat up more due to being more highly pressurized. It might cool back down through adiabatic expansion as it escapes from under the hovercraft (not sure about that), but I could see the air getting pretty toasty underneath. Essentially, although the air itself is moving through the system at a high rate of flow, you’d create a standing wave of heat in the pressurized region.

          That’s just my reasoning from basic thermodynamics, though, I could be completely off-base.

        3. AlexT, you are right and I am very wrong. Thanks.

          Yeah, on doing a proper calculation rather than vaguely remembered physics, an M1A1 of the type used in the Australian army weighs about 61 tonnes on a length 9.83m, width 3.66m, an area of 36 square metres. Down force 16622 Newtons per square metre, which just needs an extra 0.166 atmospheres of pressure.

          The pumps / blowers will be at higher pressure and hotter, but confined to within the vehicle body and the air cools as it expands into the skirt. If the hover Abrams ran over you (presumably you’re lying down) you might notice it being slightly warmer.

        4. Having been an armor nerd (among many other types of nerds, which is why I‘m here) for—checks notes—thirty years now, and having been involved in this type of discussion before, in an *even more impossibly nerdy context* than this—I can explain if necessary…it’s REALLY complicated.

          A large part of what is involved in hovercraft involves not just blowing air downwards, but *containing* that air—which means *flexible* armor, to let at least *some* escape, to manage all those problems raised above. Which technology generally constrains to be *much less durable* than non-flexible armor. You *can* armor your hoverfans enough to be invulnerable…but as discussed above, then you’re just creating a low-flying Harrier. Which maybe *could* work…except for the next problem.

          The ABSOLUTE BIGGEST problem for a hovertank is the air-hockey problem. They’re skating around on a *coushin of air*, like in air hockey—hence why hovercraft are also called “air-cushion vehicles.” WHAT HAPPENS WHEN A HOVERTANK FIRES ITS MAIN GUN?!? A modern tank main gun has ~100 t of recoil force, against 60 t weight; a hovertank’s main gun would have ~100 t of recoil force, against 0 t weight—because *it doesn’t have anything to push against.* The main source of thrust, maybe, but most of the power is going to go towards just *lifting the damn thing up*; whatever is left over is feeble compared to what’s being expended just HOLDING IT UP.

          A real-world hovertank would *never* get a second shot on a target, because its first shot would push it so far out of position that getting a second shot on-target would involve considerable extra maneuvering. On top of something like 3–4× power requirements, being generous; and I don’t think that even overly-optimistic fusion power—which I desperately hope is true, FWIW—could overcome that power deficit. You need something like contragravity to actually make flying tanks viable.

          Which isn’t to say I don’t enjoy *Hammer’s Slammers.* I mean, he got the basic explanation of the eruption of Mt. Pelee wrong, but I dunno if that was established fact when he wrote. Just…hovertanks ain’t one of the things he got right. Quite aside from his establishing *two* person crews as the norm, when *three* person crews aren’t quite adequate in all circumstances—regardless of if you have a reliable autoloader.

          1. Drake does address two of the problems you point out.

            His air-cushion combat vehicles are all armed with energy weapons, which have no recoil. Thus, they don’t have problems with recoil from firing the main gun. The energy weapons in question may be scientifically implausible, of course. But then, it’s science fiction and if a SF author wants to give their combatants ray guns, we usually give them a free pass on that.

            The other issue, two-man tank crews, is more questionable. Drake handles this with extremely sophisticated information technology. As I recall, the tank commander and driver have VR helmets to provide better situational awareness. There’s a lot of expert systems to help the tank commander remain alert to threats. And the task of operating the main gun is potentially simplified to “swing a joystick around, lock on target, fire,” which makes it much less challenging for the commander to operate the gun while keeping track of everything else going on. You can make an argument that he’s gone too far, but it’s at least superficially plausible.

          2. @grylliade

            > “it’s REALLY complicated”

            At the level of discussing theoretical plausibility, it really isn’t.

            > “A large part of what is involved in hovercraft involves not just blowing air downwards, but *containing* that air—which means *flexible* armor, to let at least *some* escape, to manage all those problems raised above. Which technology generally constrains to be *much less durable* than non-flexible armor.”

            No reason to armor the skirt. There’s literally only air behind it. Any hard penetrator can go right through. The skirt becomes less effective, but nowhere near mobility-killed. Maybe make it sturdy enough so it doesn’t get shredded by shrapnel.

            >”A modern tank main gun has ~100 t of recoil force, against 60 t weight; a hovertank’s main gun would have ~100 t of recoil force, against 0 t weight—because *it doesn’t have anything to push against.*”

            First, words have meaning. You’re talking about friction, not weight (or mass).

            Anyway, there’s an interesting discussion below about recoil and how you can actually almost eliminate it for very little performance loss.

            And in any case, an Abrams-mass tank gets pushed back maybe about 1.5 m/s (=5.4 km/h) by each shot. That’s walking pace. If a tank can’t compensate (ie accelerate) 5 km/h in a few seconds between shots, it has far bigger problems than recoil.

            > “most of the power is going to go towards just *lifting the damn thing up*; whatever is left over is feeble compared to what’s being expended just HOLDING IT UP.”

            Run the numbers, it takes surprisingly little pressure. For an Abrams-sized and Abrams-massed hovertank, skirt pressure would need to be under 1.2 atmospheres.

          3. Drake explicitly says the Slammers are the Blackhorse Cav in Viet Nam, if they were staffed partially by French Foreign Legionnaires who were former Heer (if not Actually SS); and that the combat cars are M113 ACAVs In SPACE and that the panzers are Sheridans Or M48s That Actually Don’t Suck In Space. Everything else follows. The tribarrel is a Ma Deuce in Sci-Fi costuming (at one point the grip/trigger assembly is described as being EXACTLY the same as the Ma Deuce’s), for example.

            Also, the cars are supposed to have a max thrust to weight ratio of greater than 1; IE, the skirts are optional at full throttle (Rolling Hot, the river crossing, where the team rushing to relieve Not Saigon during Not The Tet Offensive, has to cross a partially-destroyed bridge without abandoning their panzer element).

            Form follows function in Drake’s work, but you need to identify the story function to know why the in-universe form is that way.

      2. Ogre GEVs are “armor units” because the game classifies combat units (non-archaic ones, anyway) as “Ogre” or “Not An Ogre”. But they are Not Tanks IMO. (I am on the fence about Missile Tanks, but don’t care enough to pick a side). Their defensive values come from their speed and maneuverability, not their armor.

        Of course, the “light cannons with fission warheads” conceit of the universe allows GEVs to carry a respectable “recoilless” punch, and GEVs are always described as spraying and praying anyway – they play the role in fiction of “aircraft” not “AFVs” (and LGEVs in particular get ALL the Dashing Young Men In Their Flying Machines tropes)

    2. How do Star Wars AFVs fit?

      For me, the AT-AT (big, four legged) is an IFV. Primary purpose is to carry infantry onto the battlefield, protecting them from heavy weapons fire on the way in. The guns in the head provide fire support against enemy infantry and also some AA fire against flying vehicles. (Though the firing arcs for AA suck.)

      The AT-ST (small, two legged) is, uh, self propelled artillery? A bigger gun than the infantry can carry, light protection against infantry fire only, crew only no real carrying capacity.

      1. I would classify them differently: In the Battle of Hoth, the primary mission of the AT-ATs is to break through the Rebels’ defenses and destroy the shield generator. The AT-ATs can do this because an AT-AT is very well armored and thus resistent to most fires and has very strong main cannons. So at least in that particular battle it is used like a Tank, not like an IFV. The AT-AT is very large and I think it is possible that the designers decided that you could fit the supporting infantry into the in-between spaces of reactor, weapon system, etc and a dedicated infantry transport would be unneccesary. (It is, I suppose, the same principle that favors Star Destroyers carrying their own fighters instead of having dedicated carriers.)

        About the AT-ST, in Empire Strikes Back all that can be said is that the are present at the Battle of Hoth. In other movies we see them mostly used against infantry, both in Return of the Jedi and in Rogue One. In The Mandalorian Cara Dune says that they were extremely dangerous to infantry. I guess we could call what the AT-ST does infantry support and reconnaissance. Today IFVs do that, and before that it was the role of light tanks.

        (It is interesting that there are little dedicated AA systems in Star Wars, and the ones we are shown don’t seem very effective. Most fighters are taken down in dog fights. Maybe the Empire wanted to bring their own air speeders to Hoth, but the temperature rendered them ineffective and unlike the rebels they didn’t have long enough to fix this problem.)

        1. I’m not sure I understand what the point is* of a “speeder” in TESB anyway. It’s not a ground-hoverer and we don’t see it used as a full aircraft either.

          *other than “Rule of Cool”

          1. Rapid recon, especially in drastically bad terrain like crevasse fields. It can clear any obstacle with trival ease while carrying moderately heavy weapons.

            I think the Hoth snowspeeder is actually a technical, guns strapped to a civilian model, hence having a tow cable hitch. Aside from their quite excellent fighters, most Rebel Alliance stuff is converted civilian stuff, albeit in a context like the age of sail where a civilian ship can mount a few anti-piracy guns.

          2. The snowspeeder is explicitly described as a technical in the novelization, and implicitly in the movie; Han has to go out on tauntaun-back because the snowspeeders are in the middle of being converted to warcraft (and to get their hothmod kits)

        2. I’d note that the acronyms are “All-Terrain Armored Transport” and “All-Terrain Scout Transport” so clearly transportation is considered a key role. The AT-AT does bring pretty heavy armor and firepower to the table, though. It might be that various constraints were such that they considered it more practical to have one really big walker than two types of smaller walkers.

        3. One possibility is that the Empire has strong motives to discourage the mass production of AA weapons because they’re the ones who can afford vast numbers of flying vehicles.

          Sure, it means the Imperials have nothing but TIE swarms to rely on when an occasional Rebel X-Wing attack swoops in, but it’s worth it if it means that all the OTHER TIE swarms busy oppressing random planets all over the galaxy don’t have to worry about some lucky guerilla with the equivalent of a Stinger missile blowing up one of their TIEs.

          The Empire probably enjoys the advantage of having air and armor support present much more often than its enemies.

          1. I’m inclined to assume that it’s the opinion of designers in-universe that ground-based AA is just bad at its job. Certainly, anti-fighter turrets on warships and the Death Star don’t seem to be particularly great, and the old EU presented the rebels as having a major advantage in space warfare because they had quality fighters and pilots. The space combat was heavily inspired by WWII after all, in which ground/ship AA was in fact kind of bad. Not totally useless, but it took an awful lot of flak to actually score some hits.

          2. The Empire presumably attempts to have a monopoly on all military equipment, not just AA guns. And I don’t think the Rebellion uses much captured Imperial equipment. I think they’re probably scrounging up pre-Imperial equipment, of which there must be loads. The Empire only lasts 23 years, and rules over a civilization that has had pretty much the same technology for thousands of years.

    3. Wheeled vehicles with (relatively) big gun turrets are armored cars, a category Brett didn’t cover. Most armored cars are relatively small, and nominally meant for cavalry/reconnaissance duties. Wheeled means not enough armor for a serious fight, and limited to roads and relatively firm open ground, but they can move fast in the terrain they can move through at all, fight well enough to deal with light screening forces, and when they meet serious opposition, there will be a radio to use for shouting “please send real tanks ASAP”.

      Some of the larger modern armored cars, like the M1128 you cite or the Italian “Centauro”, are more properly tank destroyers. Tank destroyers are the most tank-like of the not-a-tank vehicles; they’ve been through several incarnations and there are two very different subclasses in present use (the second being dedicated ATGM carriers); the common theme is that they are generally a specialized mobile blocking element designed to defeat enemy tanks in an ambush but without the armor or general versatility needed to prevail in general combat.

      Armored cars are also quite good for internal security / antipartisan work, and often used for that purpose. They can’t chase partisans into deep woods or mountains, obviously, but neither can tanks and the armored cars can efficiently patrol the roads and towns you most need to keep partisans out of. The lighter machine-gun or autocannon versions chew up infantry nicely, the ones with big guns will demolish any building they try to hide in, and the light armor isn’t as much of a handicap when the enemy mostly has rifles and molotov cocktails.

      And the Star Wars AT-ST fills the reconnaissance-type armored car niche fairly well, to the limited extent that giant walking robots can do anything well.

      1. > Wheeled vehicles with (relatively) big gun turrets are armored cars, a category Brett didn’t cover.

        Unless it’s an armored train or railway gun! Those could be huge and are also not tanks.

      1. Heinlein also has them in the end battle against the American theocracy in “If This Goes On-.”

      2. Attempted with the Soviet T-35 in the interwar years.
        https://tanks-encyclopedia.com/ww2/soviet/soviet_t-35.php
        Not very effective, turns out to be impractical to coordinate the fire from all those weapons in a useful manner. And puts too many eggs in one not-that-well-armored basket. Each turret needs a dedicated commander, and a dedicated chassis to put it where it most needs to be.

    4. Alpha Centauri very much penalizes you for putting both heavy armor and heavy guns on a speeder, but I actually do occasionally find it worthwhile to make a defensive speeder to reinforce lightly defended territory, or for psy combat

  18. > there is, of course, a sidebar to be written here on German ‘assault guns’ – Sturmgeschütz – and their awkward place in this typology

    Why are they awkward? They are the same thing as infantry tanks and French tanks. Pinning, assault, exploitation — “proper tanks” are designed for exploitation and are functional in assault as a happy coincidence, as it were. But if you cannot afford to mechanize the whole army, you design a separate tank for the assault role, to work together with infantry that marched there on foot and with towed artillery, such that it doesn’t matter whether the tank is useful for exploitation. (Or if you only design tanks for assault because your doctrine forgot that exploitation was a thing.)

    Am I missing something?

    Separately: it is weird that (half-tracked) open-topped vehicles’ vulnerability to air-bursting shells is made an important point, without any mention of the VT fuze, i.e. that the threat of air-bursting shells massively increased in the meantime.

    1. Last paragraph: Absolutely. The VT-fuse did not have wide spread use in Europe until late 1944.

      Prior to that German SdKfz 251’s were good IFVs. Which is why the Germans developed the modern IFV.

    2. According to German doctrine (not necessarily actual practice late in WW2), the Sturmgeschutz was to be used concentrated to take out major obstacles (see Guderian’s lamentations on use of StuGs as tanks or as pill boxes). Infantry support, yes, but effectively focused direct fire artillery. It was not intended to be used like an infantry support tank, for which the Wehrmacht had no time at all.

      1. That does sound awfully like the role of a Churchill or KV-1. With the difference that the Churchill could either lead the assault and be followed by the infantry, or let the infantry lead the assault and support them from behind.

        Perhaps a Sturmgeschutz was an infantry tank designed and operated by the artillery.

        1. The difference was that the assault guns were to be used en masse for a specific major task, then withdrawn to await the next major task. They were not to be used in penny packets as general infantry support to clear MG nests, etc, but for specific major decisive tasks identified by senior commanders. So each gun was not working with a small infantry unit; the whole mass was to be deployed as a distinct direct fire force.

          1. Is there any reason to believe this would have worked better?

            This may be a case of Guderian overestimating the value of concentrated armor, especially since by the time StuGs showed up, the Germans were already having problems with the many cases where Allied armor showed up to the battlefield and their own armor did not. Having 50 superheavy breakthrough tanks does you very little good if the enemy’s 250 medium tanks cave in your entire front line.

          2. Actually von Manstein started working on the Stürmgeschütz in the early ’30’s. The Stürmgeschützschule was established in late 1937. [pg 13 & 16, “Vorwärts Immer, Rückwärts Nimmer!”, Thomas Anderson, Müller History Facts, 2011]

    3. Airbursts were still A Thing prior to the VT Fuze; as might be assumed from the “code name” for the VT fuze being “variable-timed”

      You just needed either direct observation of the fall of shot by the fuze setter, or really good spotters with really good spotting reports.

  19. It seems to me—not just from this post, but what I’ve read elsewhere about armored fighting vehicles—that the development of the main battle tank make lighter tanks go away, it just got them relabeled “self propelled artillery”. The “tanks” of WWI are pretty clearly assault guns by 21st century standards, and even the medium tanks of WWII are arguably more similar to 21st century SP artillery than they are to modern MBTs. Like, okay, their armor was twice as thick as what you’d see on “light” armored vehicles today, but the thickest armor on an M1 Abrams is over *two feet thick*.

    The thing about that sort of design is you can’t have armor that thick everywhere, so (as Bret alluded to) MBTs wind up having side, top, and rear armor that’s nowhere near as thick as their top armor. The thing about the Javelin is that it’s designed to go up and then come back down, hitting that thin top armor. Drones may also make hitting tanks from above much easier. That’s a real problem for the MBT’s basic design strategy, and it makes me wonder if we’ll eventually see militaries move away from them in favor of lighter designs. (Which may not be called tanks—I imagine some pedants will insist they aren’t.)

    1. There have been tremendous advances in the design of propulsion systems for tanks. (Note that the Abrams is the only tank system that uses a gas turbine engine that gets about 3 gallons per mile.😏.) Along with Israeli Trophy protection system.

      1. *Looks it up*

        Wait, tank-based antimissile systems have been operationally deployed for over a decade? I am surprised I have not heard of this. It seems like such an obvious must-have for a tank that I’d assumed they were stuck in development hell.

        1. The problem with active defenses isn’t that they don’t work.
          The problem is that it’s a Hard Problem to reliably distinguish between “incoming fire and enemy infantry” and “outgoing fire and friendly infantry” and the active defense system doesn’t care which set the target is in.

          This is one of the reasons the US doesn’t like ERA (explosive reactive Armor); the other reason being that modern composites (with optional DU plates) are about as good at defeating monroe-effect shaped charges. (AKA HEAT rounds).

          The Israelis have a very different cost-benefit analysis environment than the US does.

          Also, no effective tank design ever has had even armor protection all around, they’re always been front first, sides next, top and rear afterwards.

    2. Doubt it. Front armor is thickest because that’s where the greatest threats tend to come from. If top down attacks are dangerous enough, designers will redesign tanks to defend against those attacks. At a bare minimum, I’m sure there’s a lot of effort being put into active defenses against top down missiles, and you could migrate physical armor to the top of the tank as well. Either way, I doubt armor will become truly useless in the forseeable future.

        1. We ran into that issue during the Lighweight Combat Vehicle study. You really want full spherical protection these days. However you can’t afford it due to weight. The hope was to find weighs to reduce weight and increase survivbility. However each center just wanted their own solution as usual. GVSC wanted new armor. ARL thought we needed more research. AC wanted to drop in a new gun (the XM360 is a ton lighter than the M256 but requires the trunnions to be relocated).

          In the end a report was written (there is a distro A version on DTIC) and that was it. About five years later we updated it but it still went no where.

    3. Since AFVs have been developed in a time of rapidly changing technology, I don’t think an absolute comparison between the armour thickness of older and newer tanks helps much.
      Throughout WW2 the tanks had enough armour to resist, at least some of the time, the guns in enemy tanks and anti-tank artillery. Tank armour would resist, most of the time, other types of artillery. The APCs and self-propelled artillery did not. Everyone knew this, so tanks would lead an assault but APCs and self-propelled artillery would not.
      Today a WW2 tank would be considered self-propelled artillery, but it wasn’t designed as such at the time, and not used as such at the time.
      Same dynamic for battleships. HMS Dreadnought from WW1 wouldn’t rate as a battleship against say Iowa or Yamato in WW2. Doesn’t mean she is not a battleship.

    4. They’ll be named “Water Troughs” or “Ballboys” or “Half-Time Lunch Breaks” or maybe even “Googlies” or “LBWs”. Or “Home Runs” or “Boundaries” – or “Meals On Self-Laying Track Vehicles” if their opponents include Aliens with corrosive blood types … 🙂

    1. I would love to read fantasy counterinsurgency fiction starring the crew of a war elephant as they patrol not-Baghdad, scanning crowds for an eight-year-old carrying a Necklace of Fireball…

    2. Depends if it is supposed to trample and gore the enemy, or is just a platform for archers.

      1. If I remember Bret’s war elephant posts correctly, the elephant itself kills more people than the archers on its back.

        1. And, like tanks, ultimately proved to be vulnerable to the proper infantry tactic: avoid frontal confrontation, let it pass through your position and then hit it from the rear.

  20. Tanks a lot!

    (I don’t care how many others made this pun before me, I wanna chance to post it!)

  21. As someone who works in the large caliber world I need to make a couple of comments.

    First in the early days of Future Combat Systems, there was serious work done on hover tanks. They are technically feasible.

    As for autloaders, we developed one for the Abrams in the late 90’s. There is current work on a new one that maintains the safety of the armored bustle. The biggest resistance has always been what to do with the loader position. Under some of the various lightweighting studies autoloaders and pedestal mounted guns have been proposed but were always meant with resistance. The school houses had issues with it because of doctrine and training – security and maintenance focused on four people. Also there was the fact that it takes a certain number of people to justify the general’s star. I think the loader will eventually becomes either a remote weapons or drone operator.

    The recent announcement that ASA(ALT) is taking the lead in R&D over the CFT’s means thing will be changing in the next year or so. Prior to that decision NGCV was looking at either partial or fully automated tanks.those will definitely require autoloaders. The big disappointment with most public roadmaps though was that they used main guns we had developed in the early 2000’s – MRAAS and XM360. There is some recent emphasis on increasing lethality though so maybe that will change.

    A couple of gun technologies that always seem to get sidelined though are Raven and FOOB. Both would allow large guns on light platforms. The Stryker with the 105 can only fire a few degrees off of center due to recoil forces. They tried putting a pepper pot brake on it but it removed all the hardware for the vehicle. FOOB is fire out of battery. You toss the gun forward and fire while moving forward. It greatly reduces recoil but by the time you design for hang fire and misfire most of the advantage is gone. Raven is a venting cannon. You open the breech while the round is in bore. If you tine it right the round never knows. You can knock out 75% of recoil and 50% heat input but keep full muzzle velocity. Or go full recoilless with 5% muzzle velocity loss.

    Suffice it to say that there could be some serious changes to “tanks” in the next decade or so.

    One thing to remember about all the dead tanks in Ukraine is that the Russians were not using them properly. As noted in the article they need infantry screens amongst other things. Published reports show that if a tank is properly hidden (i.e. hull down) it can pop out, shot and return to hiding in 6.5 seconds. This keeps it fairly immune to javelins and such out to at least 3 km. There just isn’t enough time for them to acquire the target.

    1. > First in the early days of Future Combat Systems, there was serious work done on hover tanks. They are technically feasible.

      What happened with that? Should allow virtually unlimited mass, right? Was it due to reliability, fuel, or.. ? Thanks

      1. Besides the technology not being there yet, the hover tank as a co cept suffers from a major and perhaps insurmountable flaw. Recoil from the gun will cause a hover tank to float backwards every time it fires. New tech like laser weapons might fix this, but a hovering tank with kinetic weapons is liable to spend alot of time being punched around by it’s own gun.

        1. Recoilless guns aren’t a novel concept, and the OP had two cool ways to deal with recoil. He also said that research found the hovertank a practical application, so “technology not being there yet” might be an overstatement.

          Also, shooting a 4kg slug at 1800m/s would impart on a 25t tank about 30 cm/s, less if it’s heavier, which should be easy to correct. Would have messed with your aim before computer aiming, but that’s no longer a problem.

          1. You forgot to take into account the inertia of the gas column. That is where most of the recoil energy is. You have four+ times as much propellant as projectile these days. To compute the end load on the cannon take the max chamber pressure (103.5 ksi) times the area of the 160mm diameter chamber. That is the force pushing the cannon rearward ~3.5M pounds

        2. Lasers suffer from being blocked by rain, snow, fog, dust and smoke. Maybe a sufficiently powerful beam can punch through them but at a severe loss in power and range. In addition they have zero non-direct fire capability.

        3. There are recoilless technologies for large caliber weapons. Both fir out of battery (FOOB) and rarefaction wave (RAVEN) guns have been demonstrated in large caliber guns. They don’t suffer from the excessive propellant loads of traditional recoilless technologies.

          The big problem with lasers will be the power supply. The same issue railguns had.

      2. I have to admit I thought the confusion was going to be between tanks and tank destroyers not tanks and IFVs.

        > attempting to use IFVs like tanks is a good way to lose a lot of IFVs.

        True. But interesting historical note that this sort of happened during the battle of 73 easting and two IFVs ended up destroying 5 tanks.

      3. It was back when I first started so don’t have remember the details. I think it was technically part of Army After Next which became FCS. I know concepts were done and basic feasibility studies but think that was about it. Though they did come back up at a meeting last week.

        My guess is instead of hover tanks you will see unmanned UAVs with heavy firepower before hover tanks

        1. I imagined for a moment quad copters with heavy recoilless guns. Acronyms are great.

          Anyway, very interesting, thanks!

          1. Pretty good guess on what might be coming.

            A couple years ago I pitched 81mn mortars on weather balloons…..

    2. “Raven is a venting cannon. You open the breech while the round is in bore. If you tine it right the round never knows. You can knock out 75% of recoil and 50% heat input but keep full muzzle velocity.”

      What happens inside the turret if you try that? Presumably the whole point is to allow the exhaust gasses to escape through the breech. I wouldn’t think anyone would want to be near the breech.

      1. You need a pedestal mount or a cleeve turret. Back blast plus muzzle blast is about the same as the current M256. Back blast danger area is a lot less then old recoilless rifles or the MLRS.

        However it is a radical departure from traditional armament so it has been hard to sell.

    1. The “this is a tank / this is not a tank” comments were hilarious enough without it. Especially when showing a photo of nothing but a barren field 😀

      A very enjoyable read, anyway.

  22. I really loved this article. As someone who is curious about tanks and military history in general, could you mention some good books that cover the history of the development of tanks and armoured warfare doctrine across various countries in the 20th century? I would love some detailed scholarly surveys.

    1. Bruce Gudmundsson’s “On Tanks” is probably the best place to start. Though he seems to fall into the tank is obsolete camp.

    2. You could even just do an image search online for tank evolution. Lots of charts showing how different models were modified or replaced by successors.

  23. There is, I should note, early complexity on this point, with both ‘male’ (heavy direct fire cannon focused) and ‘female’ (machine gun focused) tanks in WWI though in the end ‘hermaphrodite’ designs with both capabilities (but much more focus on the main cannon) triumph…

    WordPress doesn’t let me post images, so just imagine a gif of my avatar rolling its eyes at the apparent need to gender tanks.

    I am now being told, [the Russian vehicles] were all towed away by Ukrainian farmers.

    I know what you mean, but I still want to share the mental image of an angry Ukranian farmer pointing out the Russian army’s parking violations and had it towed to a nearby impound lot.

    Okay, enough jokes. Um…I wonder how mechs in a setting like Battletech/Mech Warrior would fit into this AFV taxonomy. (Also mechs in a setting like Neon Genesis Evangelion, though I have a feeling their sheer strength and durability relative to the vehicles they’re contrasted with would make them a class of their own.)

      1. I mean, Battletech simply recategorizes things according to it’s own categories. (remember, tanks still exist, even if they tend to play supporting roles to big stompy robots)

    1. Evangelions are more the base chassis that you equip with different weapon systems or other equipment depending on mission. Automatic rifles (around 1000 mm caliber), prog knifes, fixed mount ion cannons, spike launchers, metaphysical spears, capture cages, etc. So the tank/!tank category would depend on the specific mission.

      The advantage of the Evangelion chassis is the Absolute Terror (AT) Field which is for all practical purposes an impenetrable metaphysical force field, which can only be effectively penetrated by another AT Field.

    2. wasn’t “gendering tanks”, it was actual reporting terminology for the variants, since they didn’t have stuff like designation systems yet.
      the first viable tank was a prototype designated “mother”, later the production version was named the Mk.I. it had been developed from the “little whillie” and “big whillie” mobility prototypes (little whillie being basically an armored tractor, the big whillie having the wrap around track system which fixed the mobility problems across trenches and shell craters)
      “mother” became the basis for the Mk.II “Male”, which had various armor and engine improvements, and “mother”‘s twin 6 pounder guns in sponson mounts (which had rather phallic looks, thus the reporting name). the “female” variant removed those sponson mounts for a new design that carried 4 heavy machineguns, two per side. named in large part because the phallic cannons weren’t present. these would be deployed together.. the females providing MG fire to supress enemy infantry and light artillery emplacements, the males using their cannons to destroy enemy bunkers, machinegun nests, etc. combine arms via tank variants, in large part because the infantry couldn’t advance alongside against the level of fire a proper trenchline could put out. they had to wait for the tanks to disrupt the enemy fortifications and punch through the first lines of trenches before they could move up without being mowed down.
      the ‘hermaphrodite’ was the version that later production runs would end up building in large numbers, which was basically to have one sponson of a male variant and one of e female variant, so you had a single 6 pounder and a pair of heavy MG’s, allowing one tank to fill both battlefield roles.

      these variants would be used for the Mk.III’s (a training version), the Mk.IV’s (what most people tend to envision when they think of ww1 tanks), and the Mk.V and Mk.V* (the later a stretched hull version with limited infantry transport ability).

      so no, they weren’t gendering tanks, they just had an unconventional designation systems because no one had any sort of terminology or recording systems for telling types and variants apart yet.

  24. These post didn’t work. Usage of word changed constantly.

    Argument about difference about tank, tank-destroyer, or AFV is about as effective as arguing that “Princess Diana” usage is wrong.

    De Facto usage of tank is Armored Fighting Vehicles. Military specialist only add to confusion when they deny this.

  25. A small correction to the tank alignment chart: USS Iowa belongs in the design moderate/doctrinal moderate square, not design anarchist/doctrinal purist It clearly has a powerful main armament, but prefers to use indirect fire.

      1. Can any artillery shooting at something over the horizon be called direct fire? Admittedly battleships might be trying to hit a specific target, and have radar contact, but I think it’s a fringe case.

  26. Do tank tactics bear any resemblance to chariot tactics?

    I ask this because I have read a fantasy novel in which the protagonists, encountering the enemy’s recently invented tank-analogue (heavily armored vehicle with big guns), consult a character who was a general in a civilisation with Bronze Age technology using chariots, on the basis that the chariot (mobile, has some degree of armor, fires arrows) plays a similar tactical role.

    1. I think that war chariots were similar to ground attack aircraft or reconaissance vehicles. They had some firepower (composite bow, javelins) and good speed. The best scenario was to catch the enemy in unprepared positions and scatter them.

    2. The role of a tank on the battlefield is to be immune to standard infantry weapons (rifles and machine guns) and also carry more deadly weapons themselves (very heavy machine guns and high explosive artillery). Infantry need different weapons to fight tanks, and these weapons aren’t very useful against other infantry.

      Chariots on an ancient battlefield are neither. The horses and crew cannot be so heavily armoured in comparison to other cavalry and infantry that they become immune to enemy infantry spears, arrows, etc. The chariot crew cannot carry super melee or missile weapons. If the enemy infantry have weapons that work against armoured infantry or cavalry, those weapons will work just as well against chariots.

      Chariots may be scarier than cavalry. Chariot crew may get a little protection from the chariot body. They may be able to carry more arrows or be able to better concentrate on archery while someone else steers. But they didn’t offer any significant advantage, as shown by every chariot using army replacing them with cavalry in the ancient period.

      1. To what extent was that due to horses originally being closer in size to ponies, and only later were bred large enough to ride without the horse being excessively fatigued?

        1. It can help, but does not seem to have been all that important.

          Horse archers such as the Mongols always used small ponies, and had a logistical advantage from doing so. Bigger horses need more grain and other concentrated nutrients, you can’t just put them out to forage all the time. Bret talks about this and has a photo of a small Mongol pony in

          https://acoup.blog/2020/12/11/collections-that-dothraki-horde-part-ii-subsistence-on-the-hoof/

          The initial development of cavalry seems to have been small steps, not always requiring new stuff. Someone wonders if they can shoot a bow while riding a horse. Someone realises that a saddle will distribute the load of a rider rather than concentrating weight on the horse’s spine. Someone gets fed up with having the inside skin of their legs being slowly removed and starts riding in trousers.

          Once it’s established that cavalry are very useful, people do start thinking about more armour and weapons, and then hey that horse is bigger, maybe we can breed more?

          Cavalry generally didn’t replace chariots immediately. The various Gallic tribes in the classical world started with all chariots, then started using more cavalry and fewer chariots, until finally the chariots were gone. (There does seem to be a some cause and effect between Gallic tribes encountering disciplined Greek / Roman armies and adopting cavalry: fringe places like Britain and Ireland kept their chariots longer than the Gallic tribes in central Europe and Asia Minor.)

  27. The misleading use of the term “tank” in the twitter post of the German ambassodor is most likely just a problem of differences in German and English terminology: The German term “Panzer” is more general than the English term “tank”. In German the Gepard is actually called “Luftabwehrpanzer” (and ATPs are called “Schützenpanzer”). The correct German term for the English “tank” would then be “Kampfpanzer”, but in a dictionary you would find that “Panzer”=”tank”.

  28. As no one else has mentioned it, Nicholas Moran’s – The Chieftan’s, video about whether or not tanks are dead was a reply video to Perun, who asked that question in a click-baitey kind of title. Regardless of the title do watch the Perun video, it is very good and he very obviously knows his stuff. You can see it at https://youtu.be/mUyAPQEb01Q

  29. “It used to be that now I’d have to go on about why going autoloaders aren’t simply obviously the best but given the live demonstrations of some of the drawbacks of Soviet/Russian carousel autoloaders going on right now I’ll just say that both options have advantages and drawbacks and move on ”
    I find this paragraph hard to understand. Is It incomplete? Sorry if that’s not the case – English is not my first language.

    1. The answer is given in the immediately subsequent image and caption. Basically, if you have an autoloader, your tank will probably explode spectacularly and kill everyone inside if the main compartment is penetrated at all. There are ways to store ammunition safely so that (usually) doesn’t happen, but they generally require human-level smartness and dexterity to get the rounds from the magazine to the gun.

      The advantage of the autoloader is that it allows you to remove one crewman and make your tank smaller and thus a bit harder to hit. If your response to a tank being hit is “let’s see if we can patch that up, and if not get these highly-trained crewmen another tank”, you’re probably better off with a tank that’s a bit larger and not made of explodium. If you consider tanks and their crewmen to be expendable, then sure, autoloader + low profile means it will last a bit longer before being catastrophically expended.

      1. Yes. To be fair, not all autoloaders are as prone to ammunition ‘cook off’ (when the ammo detonates due to a fire in the compartment) as the Russian carousel autoloaders.

        1. With modern robotics you can do an autoloader that only has one round out of the bustle at a time. This keeps the same level of safety as the currently manually loaded system.

          Autloaders are currently being tested for nest Gen self propelled howitzers (https://www.army.mil/article/244447/picatinnys_extended_range_cannon_artillery_autoloader_begins_testing). Given the separate projectile and ammo that is a lot harder than the single piece cased ammo for a tank.

          I can’t talk about current tank efforts but an autoloader was demonstrated for the Abrams back in the 1990’s. The issue was what to do with the loader position. Today that shouldn’t be as much of an issue as he could operate a drone or a remote weapons platform

      2. Humanity aside considering trained men, especially trained men with experience ‘expendable’ has always struck me as very stupid.

        1. You need to talk to the Russians. They have traditionally kept the ammo in with the crew and viewed the crew as expendable. Ukraine is showing this in action. Some of this I think is the difference between a mostly conscript and all volunteer army.

          1. More like a product of a non-democratic society.

            In democratic systems, conscript armies generally cause more casualty-aversion; see e.g. the effect of Vietnam casualties on American public support for the war, or the near-pathological Israeli casualty-aversion. You can’t use the “they volunteered, they knew the risks” line when they did not volunteer.

            Coming from the Israeli perspective, the things we hear about the Russian system (mostly from Russian Jews and Russian Israelis) are bizarre. Soldiers sent off to war without their families even knowing they’ve been deployed, much less which front they’re off at; the oft-breached legal distinction between conscript and volunteer soldiers, with the former only deployable in declared wars; and of course the absolutely insane culture of bullying and hazing and alcoholism.

            Just a total disaster of a military culture.

    2. There’s some typos there, yes. I’d rephrase it like so:

      > It used to be assumed [by my audience] that autoloaders are obviously the best option, and so I’d now have to go on about [the drawbacks, to convince them otherwise]. But given the live demonstrations of some of the drawbacks of Soviet/Russian carousel autoloaders going on right now [i.e. the “this was a tank’ situation], I can just say that both options have advantages and drawbacks and move on.

      The drawbacks are described in that caption – TL;DR a good hit against the tank can set off the ammo and make an extra-large boom. I assume that this flaw was already known in the abstract, but this had not been practically demonstrated in a live-fire setting until recently.

      If you don’t use an autoloader, you need extra crew, but you can keep most of the ammo in the belly of the tank, where the maximum amount of armor protects it. Which means you have a higher chance of a penetrating hit to the turret getting your tank damaged but not destroyed, and a better chance of your crew surviving the experience. Or, in the words of Bablyon 5: “No boom today.” 😛 (If you stay in the field after that kind of hit, “Boom tomorrow” is even more certain than usual.)

      1. On the Abrams the ammo is kept on the bustle – the part sticking out the back of the turret. It has two blast doors on the top so that if a round comes in the crew gets a bad headache but survives. There is a door the loader operates with a knee switch to open that separates the bustle from the turret. The Russians keep the ammo in with the crew – thus the blown off turrets.

        If you can design an autoloader to only grab one round at a time you can keep the same protection as what the Abrams currently has. This is complicated by the fact that you want to be able to load the gun at any elevation we which becomes a real pain.

        There is an autoloader for ERCA (next gen self propelled howitzer) and that has the additional issue of separate projectile and propellant so it is doable with today’s technology. It just hasn’t been done yet.

        1. I’d be concerned that any auto-loader, especially one on a tank that’s been in battle for a few days and where it’s been competing with every other part for maintenance, would have a risk of jamming, with the odds going up the more intricate the process is.

          1. There will always be a manual backup. Besides remember that a tank engagement is only supposed to be 2-4 rounds. You aren’t out there firing all day like artillery. The whole turret is hydraulic so lots of chances for it to malfunction. Plus just getting dirt into the muzzle of the gun can cause a “major” malfunction.

    3. Anyone interested on the autoloader discussion should watch Nicholas “The Chieftain” Moran’s video “Whither the Autoloader?”. It addresses all the arguments for autoloaders I could come up with and several I didn’t even think of.
      https://www.youtube.com/watch?v=R0x-8NheU1E

      Many are aware of the dangers of the Russian autoloaders, but don’t realize the M1 Abrams has the same danger during loading. The loader has to open the blast door and it seems to be open for at least 5 seconds. On better autoloader designs like the South Korean K2 or French Leclerc there is only a small hatch that is open while the autoloader poops out a round. I don’t know what the design is behind the hatch, but I’m sure it would be possible to create one where the loader compartment is sealed of from the rest of the ammo storage while the hatch is open.

      Crash55 brought up that you need to elevate the gun to a specific position for the autoloader, but this is a non-issue with modern stabilized guns. Some modern tanks with manual loader also set the gun to a optimal loading position and then reaim to the target afterwards.

  30. Fascinating as always!

    This might be too general to be answered, but are there any general guidelines you could give on: How do I know when a particular weapon or tactic has become obsolete?

    It seems to me that usually when this happens the initial response is “we’re not winning because our military commanders are idiots” and only in retrospect is it decided that that warfare had changed.

    1. “How do I know when a particular weapon or tactic has become obsolete?”

      It’s very rarely binary, where ‘x’ worked and then suddenly ‘x’ didn’t work. It’s often impossible, even in retrospect, to pinpoint a discrete event where the status flips.

      There’s often a broad period of obsolescence, where the weapon or tactic is less than ideal – but still useful. It’s a spectrum, not a switch,

      1. Yep. You start with somethign broadly useful, then someone comes up with a countermeasure, limiting the space where it is useful, but it’s still the only thing that can do certain things, so you start avoid that thing, then as tech advances new things come up that can do the things that you need doing, and the space where you can do things narrows, until it’s no longer worth keeping the old systems around.

        Cavalry is a perfect example. Up until even post-WWII and arguably *still* there are roles that cavalry (or at least mounted infantry) are useful for, it’s just that it’s generally not worth breeding horses for those very narrow purposes anymore.

      2. Also, there are times when it’s bad before it’s bad in general, and times when it’s good after it’s bad in general.

        During WWII, Resistance fighters sometimes used bows and arrows. Besides the obvious advantage of manufacture, they were quieter.

      3. I think given that it can be decades between wars, it can often be “overnight” in that you turn up to a war and it doesn’t work anymore. The “static system” worked in WW1, but when you showed up to WW2 you needed fire and movement tactics.

  31. Hey Prof. Devereaux, would you say that Russian online information warfare is an example of a protracted war strategy as applied to propaganda? Instead of defeating your opponent in a pitched battle of ideas, you deny him one, trying instead to wear him down by forcing him to prove his points against increasingly stupid claims (tankies, antivaxxers, qanons, etc.) until nobody buys him anymore and everyone is ready to buy your point.

    Also, now I understand why the Bradley is not a tank. Up until today, I would’ve sworn it’s a result of some sort of silly-ass Pentagon politics.

  32. IMO, expect confusion to grow overall, as countries start deploying tank gun armed IFV’s. many of the nations with a comprehensive modern tracked IFV chassis, like Sweden with the CV90 and the germans with the Lynx, have been developing and marketing versions of these vehicles which give up the majority of the troop transport ability in order to mount a turret carrying the same cannons as an MBT. thus turning them into something between a light tank and an assault gun. they are usually too lightly armored to be deployed in the same way as an MBT (despite the firepower) but the development of active protection systems and reactive armor has allowed these heavy gun armed IFV’s greater survival ability (in theory) than their chassis armor alone would suggest.

    (these same developments have been applied to the IFV’s and MBT’s as well.. most of them never really tested “in anger” against peer opponents. so their actual utility is probably less than the hype)

    1. Neither the Lynx or the CV90 have tank level armaments. The CV90has a ranges from 30 to 50mm and the Lynx has a 40mm gun. Those are by definition medium caliber and not large caliber guns. The US Army sets the line for large caliber direct fire at 90mm.

      The guns on those vehicles are inline with other IFV’s and not MBT’s. Especially since even the 120mm gun on the Abrams is viewed as being underpowered.

      1. the CV90120 with the 120mm/L50 “compact Tank Gun” and the Lynx 120 with the Rheinmetal Rh-120/L44 Smoothbore tank gun would like to have a word with you.
        you are thinking of their IFV baseline variants, but both of these are chassis with comprehensive variant lists that include IFV, recon, Mortar, command vehicle, etc. and they both have variants that mount full on MBT guns in MBT style (but lighter) turrets, usually being marketed as light tanks, and filling a role bridging the gap between a light tank and an assualt gun/”mobile gun system”. (the CV90 originalyl had a 105mm version, the CV90105, which the 120mm turret replaced once the compact gun technology matured)
        these sorts of “IFV based light tanks” are increasingly common in military developmental circles, the US army was even looking into something similar as part of the future Force Warrior Program.

        1. Where are these variants? They weren’t on the Wiki pages for those systems.

          Are they developmental one offs?

          None of the light and programs in the US Army have survived for long. Last time I saw NGCV roadmaps they weren’t there anymore.

          Given what is happening in Ukraine I expect more emphasis on upgrading / upgunning the Abrams as opposed to new light tanks. At least for manned variants. I could see unmanned light tanks, but not manned ones.

          1. they are on the wiki pages, under “variants” they’re just fairly new (the CV90120 being only a few years old, the Lynx120 being revealed only last year) and haven’t been adopted by anyone yet. but they are being offered for export, and since they offer tank battlefield firepower at a much lower price you can expect there to be a fair bit of interest.. especially from nations that already operate the IFV versions, since they share the majority of their parts and thus simplify logistics.

        2. Look up Mobile Protective Firepower. MPF is NGCV’s answer to the light tank. It is still in the 30 to 50 ton range.

          GD will be the vendor (BAE was disqualified) and the armament looks like the 105mm XM35 (same gun as Stryker). It looks like the optionally manned one (OMFV) will use a 50mm gun.

          Personally I find this pathetic as the XM35 is left over from the 90’s. It is all we are doing lately with guns – take an old design, slight update and put it out again, rinse and repeat.

          The XM360 at least used composites and high strength steel.

        3. So they are developmental one offs. The US is looking to the GD Griffin for MPF and OMFV. I will be surprised if they actually get fielded. Especially since they are only looking at a 105mm gun for the MPF.

          A 105mm gun can actually compete with a 120 if you enlarge the chamber and create a whole new ammo suite but they aren’t planning on doing that. They are using the XM35 designed in the 90’s. Not sure if they are keeping the muzzle brake or not (it removed everything from the front glacis on the Stryker) but they are keeping the old ammo.

          Pretty sure the reason for the little gun is recoil. Ogorkiewicz has curves for allowable gun size (energy) vs vehicle weight.

          1. if you have sufficient precognitive ability to declare them “developmental one offs”, why are you arguing about armored vehicles on the internet instead of making a fortune on the stock market?
            they are new products recently placed on the military market. it can take a few years before countries can obtain them, even if they immediately place orders. you can’t declare them “developmental one offs” until a couple decades have passed with no orders. (like the XM8 program.)

          2. I work in the industry and I am basing my comments on what I have seen over the last 20+ years.

          3. also buying stock in a defense contractor might cause a conflict of interest. I would have to declare it at work.

          1. Cheaper, I expect. If you agree that tank armor isn’t effective against antitank weapons then it makes sense to save money by not having it. My understanding is that tank armor is still at least somewhat effective against even latest-generation tank cannons and RPGs and there’s plenty of old antitank weapons out there, though.

            But if ATGMs are the way of the future and no practical armor solution can be devised, then IFVs with tank cannons are just as good against them and you can spend the armor money on active countermeasures.

          2. Air drop. The Abrams is too heavy. Though most of the proposed light tanks are also too heavy. The US Army is looking at the GD Griffin for MPF and OMFV. Though for the second it is down to a 50mm gun.

            The ultimate goal is always to get a “tank” on a C130 as it allows access to most of the globe. However the lift limit is 30 tons and the ramp can only handle like 15 tons.

          3. So, Crash55, the old airportable tank idea. I cannot help but think that tanks are all about concentration of force, and lightweight battle tanks are always going to fail against full-size ones.

            Airportable battle tanks will have to wait until the weight limits imposed by aircraft are less severe than those imposed by the need to fit through the conventional road infrastructure.

            Airportable recon vehicles or tank destroyers, like the CVR(T) family, are altogether more reasonable.

          4. As I understand it the main idea for air-portable tanks is to use them in airborne assaults, where you can have an air-portable tank or you can have zero tanks until your reinforcements break through.

  33. Can someone explain what exactly Tank Destroyers are/were in comparison to tanks? If I’m playing a WWII tactical game, I’ll have some of these and I can’t figure out what to do with them. As far as I can tell they mainly seem to be the same as tanks but with the gun fixed instead of on a turret. What were the differences in how they were used and why did they even exist? Thanks

    1. mostly? tanks that the army redesginated as something else to keep armor branch happy, and then gave over to the infantry branch.

      the cheiftan has a great video on the development of the tank destroyer, and what exactly it is here:
      https://www.youtube.com/watch?v=7ho8TU_JpoI
      early anti-tank efforts were honestly their own thing using towed and self propelled artillery, but battlefield needs generally pushed development into basically light and medium tanks which gave up armor for higher speed. the main reason they got labelled as something else was internal politics stuff

      1. of course that was the US military version. other countries tended to follow similar lines though. one of the reasosn that so many non-american tank destroyers lacked turrets for example, is they were being built on self propelled artillery chassis (which had been filling anti-tank roles as a secondary) or on assault gun roles (SP light artillery used in a direct fire role).
        but ultimately a tank destroyer is just a tank that was specialized primarily to fight other tanks, in an period where most tanks tended to fill a more general role.

    2. Tank Destroyers are generally designed to fight only tanks and fire from ambush or protected positions. If they’ve got heavy armor, which is by no means a certainty, it’s usually directed forwards to an even greater degree than normal. If they get flanked by a tank they are going to have a very bad time.

      They existed because it was really expensive to build something with armor and a turret that’s got a gun the size of the ones the tank destroyers mounted. I’m not sure of the details, but our ability to put bigger guns in turrets improved and the Abrams has a bigger gun than any tank destroyer.

    3. Doctrinally use them like ATG’s. Basically they are self propelled ATG’s. Best used as prepositioned defense, that can more quickly reposition than towed guns.

  34. For those interested in armament design I would suggest looking for the following publications:
    Rheinmetall Handbook of Weaponry
    US Army AMC Design Pamphlets – AMCP-706-*****

    There are many different AMCP’s available. They cover all aspects of design as of the late 1960’s. Most are available on DTIC. Most have an index in the back listing all the different ones.

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