"Help w/ tank design good ones bad ones" Topic

In a speech I am going to give in the future, I thought I would compare the subject to tank design. When I was at the tank school, they told us the best tanks were a compromise between armor, protection & mobility. If you increase one, it comes at the cost of the other two. SO am wondering if the good folks here could help me with some out of balance tanks:

For example:
King Tiger: good gun & armor, but lousy mobility

or maybe something that was mobile w/ good armor, but had a bad gun/

So any examples that were good at one aspect, but bad at others please.

T-34/76 – good mobility and armour, gun not so great against other armour.

Early model of Pz-111E, with the 37MM gun.

Italian M13/40 good gun, decent mobility, barely bullet proof armour.

Just a couple of thoughts.

Sherman, excellent mobility but not such great armour and weak gun until later versions.
M18 tank destroyer. Excellent mobility excellent gun very tbin armour.

Sheridan for more contempoary examples?

Churchill good armour, slow but surprisingly had decent mobility in rough terrain, poor gun for anti tank work.

Marders, Nashorns, Archer etc reasonable mobility, good gun, poor armour.

Cruiser tanks and early Crusaders good mobility, poor gun, poor armour.

T-34/76 – good mobility and armour, gun not so great against other armour.

It did just fine against the Pz IIIs and IVs that were its main opponents. It only ran into trouble when the Tiger was introduced, but then so did every other Allied tank at the time.

Actually when you account for the sloop on the front of the Sherman it was just about equal to a Tiger frontal armor in thickness. The difference was the Tiger had a much better gun for penetrating armor.

Pz I ausf F good armor, poor gun, poor mobility

or maybe something that was mobile w/ good armor, but had a bad gun/

Churchill, up until the 75mm versions, and even then that was only an adequate gun.

The Abrams can arguably be in the "poor mobility" category because it's so heavy it can collapse bridges and even sewers.

Leopard 1 is the poster child for good mobility and gun, poor armor.

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I'd actually use the tetrahedron instead of the triangle: Gun, Armor, Mobility, Availability/Maintainability.

The Guns / Armor / Mobility equation lacks a couple of key considerations.

Despite what Mserafin might suggest about gun vs. armor of the T-34, the Pz III was a stunning overwhelming success in 1939-42. In both the west and the east it operated at a highly positive kill-to-loss ratio against tanks that were better armored and/or had better guns, and perhaps most importantly it was a key factor in many successful operational level campaigns. The two primary advantages it had were a better crew configuration (both better crew duty design and better ergonomics for the crewmen as they did their duties), and better operational-level mobility.

So don't leave out crew considerations in the design. I suggest two levels of crew consideration – what are the crew duties (the dedicated commander in Pz III and IV gave the Germans a SUBSTANTIAL combat edge over many opponents), and how is the ergonomic design (I would have hated to be a driver in a T-34!).

So I would add a fourth element, on crew design, to the guns / armor / mobility balancing act.

The other thing is, when you speak of mobility you need to differentiate between battlefield mobility, operational mobility, and strategic mobility. Tigers had battlefield mobility that was almost a match to the M4A1 Sherman. About the same top speed, about the same ground pressure, not as good acceleration, but better steering. But the Sherman had FAR better operational mobility (moving Shermans 150 miles was far easier than moving Tigers 30km) and FAR FAR better strategic mobility (there was only ONE port in all of axis-controlled North Africa that could handle Tiger tanks. So Rommel never got any. (There were other reasons too, but even if, there was no port available to off load them in all of Libya, so no Tigers until Tunisia fell into German hands.)

Just some ponderings …

-Mark
(aka: Mk 1)

In a speech I am going to give in the future, I thought I would compare the subject to tank design. When I was at the tank school, they told us the best tanks were a compromise between armor, protection & mobility. If you increase one, it comes at the cost of the other two. SO am wondering if the good folks here could help me with some out of balance tanks:

For example:
King Tiger: good gun & armor, but lousy mobility

or maybe something that was mobile w/ good armor, but had a bad gun/

So any examples that were good at one aspect, but bad at others please.

@Korvessa,

there are two other factors I would assert that are critical to successful tank design; the reliable two-way voice radio and *ergonomics,* as in the interior layout of the crew compartment and the number and job descriptions of the individual crew members (I won't even go into doctrine).

With the introduction of reliable two-way voice radio communications, the coordination of constituent tank units out of immediate line-of-sight with one another became possible, with an increase in operational and battle tempo previously impossible with flag signals and written or verbal orders as the sole means of communication between individual tanks.

Ergonomics made a big difference in terms of tactical efficiency and crew fatigue. The Germans were the first to truly grasp these nettles, while the Western Allies and the Red Army were a definite second in these categories.

Examples of tanks with superior firepower, armor protection, and equivalent or at least acceptable mobility were the SOMUA S35 and the Char B1bis. Both suffered from the appalling persistence of the one man turret in French tank design from 1918-40, although both were armed with a turreted gun (47mm Mle37) capable of breaking the armor of any German AFV in service in 1940 at combat ranges, while their armor rendered them nearly impervious to the standard German AP weapons of the day. A further confounding factor was how outmoded doctrine conspired to inflict a short range on the French tanks, as they were engineered from the premise of Great War (Western Front) battlefield conditions, so long range was not considered as crucial a factor as armor protection and firepower.

The German panzers of the same period had an optimal five man crew laid out in an optimal fashion, placing the tank commander in his cupola able to both see with his own eyes when needed *and* concentrate on directing his tank in battle without too many distractions. His subordinates in turn had one(1) job to concentrate on, so unlike for example the radio operator in the SOMUA S35 who doubled as a shell and magazine passer to the overworked tank commander/gunner/machine gunner/you-name-it occupant in the S35's turret, the German radio operator could keep his ears and eyes on his radio set and when needed with minimal comparative distraction make himself useful with the bow machine gun in the heat of battle, yet still not be turning and contorting himself in his seat digging out fresh shells AP or HE and machine gun magazines to pass up to the turret occupant while ducking falling spent 47mm brass shell casings, and trying to follow the radio chatter while he was at it.

The British, French, and Russian tanks tended to have the tank commander at least double as the gunner in their machines (ie., British cruisers, French ACG-1, and Russian T-26 and BT-series fast tanks), thus distracting and limiting the situational awareness of the tank commander accordingly. The first T-34/76s and the KV-series heavy tanks had a similar problem, with the turret crew lacking a turret basket with a revolving floor, and ammo stowage being located under the fighting compartment flooring under rubber mats, which in the heat of battle became a tangled mess of pulled up rubber mats and spent 76.2mm shell casings the turret occupants had to negotiate as they worked the turret.

Armor, firepower, and mobility can be greatly reduced in their value through poor ergonomics and a lack of two-way real time communications capability. Throw in poor doctrine and lack of training, and you can have a superb enough tank on paper as the French Army did in 1940 and the Red Army did the following summer, but it will do you little good against an opponent who has a more balanced approach and a doctrine that takes advantage of superior mobility and the ever critical logistical considerations involved in modern mechanized warfare.

Hope this helps!

Leland R. Erickson
Metal Express
metal-express.net

Actually when you account for the sloop on the front of the Sherman

Well if you stick a warship on the front of any tank it will increase the armor…….. ;)

Also notable is the situational awareness, which is alluded to above, partly the commander being able to command as a full time role, but also the visibility options, optic quality etc. The commanders cupola when introduced was a major improvement.

Centurion – armour was very good and it could take a lot of punishment, armament was excellent, and as for mobility, it might not have been fast but it could go just about anywhere including places other tanks couldn't.

Good/bad is somewhat relative. A 2pdr in 1944 is bad, but in 1940 it is hot stuff, one of the most effective tank mounted AT guns of the era.

So an A13 in 1940 is good mobility, good gun but poor armour. Appalling reliability:)

Matilda II, good gun, good armour, slow.
2pdr Churchill in 1943, good armour, poor gun,poor mobility.

Fast and well armoured with a poor gun is an odd combination and I can't think of any examples.

Perhaps that heavy armoured pz2 variant?

I don't think the gun is a big factor. The only issue comes with turret ring size. The PzIII couldn't mount a long 75mm in a turret – so the StuG III did that job – and pretty well.

There is little benefit in mounting a weaker gun than is possible in order to get more mobility or more armour.

IMO – the best order would be gun-armour-mobility. Find a gun that can do what is needed/anticipated. Add 20-30% just in case. A tank that can't kill it's prey is useless.

Then give it as much armour as you can in the vital areas while remaining mobile/reliable.

These seems to be the strategy behind the IDF tank designs.

Things like the M18 sound great in theory but if you can't take a hit then you won't last long in a fight. The M18 was really just a mobile ATG – not an AFV as such.

Same goes for the Leopard II which seemed not to have enough armour to survive – though it WAS quick and had a great gun/fire control.

One of my 6mm Slammer HBTs …

Now that being said, note the "bottle cap" turret. You saw this on later Soviet designed AFVs. No shell traps like you see on many AFVs in the past and now.

Also note the sloped hull all around. Something you didn't see too much in the early AFV designs. The Panzer Mk.I thru IV and Mk.VIa, all had flat hulls – front, side & rear. The Germans took the idea from the sloped hull of the USSR T-34 for their Panzer Mk.V and Mk.VIb.

Someone has said it already but I'd go for the centurion.

One other aspect to consider is obsolescence. Tanks can be very good when introduced, but fall behind in one or more categories with a single technological advance in another category. For example, armor in the late 40s and 50s could withstand most tank cannons until the widespread introduction of improved shape charge and sabot rounds. The M4 Sherman was state of the art in 1942, but was outclassed in firepower and armor protection by 1944.

The point is there is no perfect tank. All tanks, through history, have had some area that could be criticized. Your point, however, is a good one and that is compromise.

As to another example would point out the T-54/55 and T-62 designs. Simple, robust, good armor, good gun and good mobility (all for their time of course) it came at a price. The low silhouette limited their abilities to take hull down positions. Also the Israelis discovered that the ergonomics were horrible. In the tanks they recovered and converted for their own use they found their tank crews were wearing out. They also suffered from the layout and cramped conditions such that their abilities to function decreased at an alarming rate.

I think your talk would do very well pointing out the compromise aspect of all designs. It might also center on how doctrine or tactics for a particular country might drive where to make those compromises.

Surprised no one has mentioned the Grant/Lee tanks, with the side-mounted, sponson main gun, little popgun in the turret, and riveted armor.

Worked okay at the time against some inferior enemy weaponry, but was definitely a design failure, since we don't see tanks with side-sponson guns being produced any more.

The riveted armor was a huge danger to the crews as well, since when hit by enemy fire, they tended to create interior spalling, wounding and killing the crews.

Apparently, the US couldn't cast turrets large enough at the time in order to hold the 75mm gun, which is why they went with the mounting scheme they used, instead.

Then, of course, there was the German Elephant (Ferdinand), which really isn't a tank, since it doesn't have a rotating turret, but did have a nice, large 88mm gun, for long-range tank killing. The designer failed to provide any machine guns for it though, and so when they broke down, or became mired in snow and mud, they were very vulnerable to attack by Russian infantry. Quite a few were lost to them, due to that oversight.

Interesting that cost isn't a consideration.

If you're a crew member of an AFV, you don't want to be in a "death trap" from a low bidder contractor …

Surprised no one has mentioned the Grant/Lee tanks, with the side-mounted, sponson main gun, little popgun in the turret, and riveted armor.

Worked okay at the time against some inferior enemy weaponry, but was definitely a design failure, since we don't see tanks with side-sponson guns being produced any more.

The riveted armor was a huge danger to the crews as well, since when hit by enemy fire, they tended to create interior spalling, wounding and killing the crews.

Apparently, the US couldn't cast turrets large enough at the time in order to hold the 75mm gun, which is why they went with the mounting scheme they used, instead.

And isn't it funny how the M3 Lee/Grant and M4 Sherman shared the same chassis? Not to mention suspension parts?

Well, apparently it was reliable, and worked fairly well as an assault gun for providing close fire support, but certainly not something you'd want to be in on a battlefield, when up against opposing tanks with turrets that could fully rotate.

The French AMX30, introduced in 1965, famously emphasised mobility and firepower at the expense of armour. It was light, fast and had a good punch by the standards of the time, but was considerably less well-armoured than its contemporaries. The design assumption was that speed and compactness would make up for lack of armour.

As time went on, the French seemed to be less sure of that particular compromise. Subsequent models got heavier and its eventual replacement the Leclerc is more the 60 tonne beast we are familiar with today than the 35 tonne whippet of the original 1965 model.

C'mon Legion, you've been around enough to know the saying, "Never forget your (whatever) was built by the low bid contractor…"

Reminds me of the statistically incorrect but commonly cited running joke in Army Aviation: You only need a 70% passing grade to be a pilot, crew chief or air traffic controller. That means on any given flight, there is a 90% chance of somebody fouling up.

Well the Lee was only ever intended as a stop gap to get that 75mm gun on to the battlefield pending the development of the M4 series, and the Brits who received them appreciated the firepower that 75mm brought to the (sand) table: an HE round that outranged the German 75mm in the Pz IV then in service and something other than an MG to hit back at those dug in Pak 36's and 38's with. (BTW at that time the 37mm was not yet a 'pop gun', being as good as or better than the 37mm on most of the Pz III's).

There was no such thing as the shell proof tank until perhaps the Abrams came along. As the Germans found out, slapping ever more armor onto your tanks just makes them harder to move around and maintain when the overworked power train gets worn out. And all that weight still relies on a series of pins and washers to hold the track links together….

The best defense is a good offense, and you need a gun that can handle dug in infantry as well as enemy armor, coupled with the ability to get where you need to go – into or out of trouble – and as much armor as you can add without compromising the other two factors.

Wargamers really should get their heads around the fact that the war didn't start in 1944 with Tigers and Panthers being the stick to measure everything else by.

C'mon Legion, you've been around enough to know the saying, "Never forget your (whatever) was built by the low bid contractor…"

LOL ! You got that right !

Reminds me of the statistically incorrect but commonly cited running joke in Army Aviation: You only need a 70% passing grade to be a pilot, crew chief or air traffic controller. That means on any given flight, there is a 90% chance of somebody fouling up.

Being a PL in the 101 then later the Bn S3 Air, I think I've heard something like that too ! Of course, we were always glad to just be landed in the right LZ ! Which usually happened … But not always. Especially in the dark. Once you were on ground and you figured out you were not where you were supposed to be. Sometimes it was a long walk in the dark. And the it would start to rain ! Of course this was before GPS …

[Sorry to go OT gents … mea culpa …]

To a Grunt, the best tank design was one that was on your side shooting at tanks on the other side !

When considering the process of design (whether of an tank or anything else) you also need to ask yourself "what was the designer trying to do?". The much maligned Italian CV33/35 series tankettes were obsolete and outclassed at the start of WW2, but when they were designed the Italians expected that the next war would be fought in the mountains, mirroring their experiences in WW1. A light tank that can maneuver on mountain tracks and cross light wooden bridges was their goal, and they largely succeeded. Especially considering the woeful state of heavy industry in the country at the time.

One must be careful with anedotes re tank superiority. While its appropriate to add ergonomics to the traditional factors: gun/armor/mobility, its not the final answer. Crew quality and operational/tactical manuver play a great role.

To take France 40 as an example at Stonne a single CharB smashed a whole column of German PzIIIs & IVs in a Michael Whitman like charge. Superior armor and gun vastly more important than one man turret (in this case).

In another action a whole unit of CharBs were wiped out by not the 3-man turreted PIII & IVs but by 2 man turreted (like "inferior" T34) Pz38 – winning by manuver (taking them in the flank while they were refueling).

Yes the Germans had a good kill ratio in '41 but it was mostly aganist BTs, T28s & T26s (the Russians had only about 300 T34s). Once more T34s appeared the Germans (by their own admission) had troubles in tank fighting. Operational and tactical manuver advantages keep them ahead. But the need for a better tank became a priority.

Again crew quality is the single most important aspect of tank fighting but has nothing to do with tank design. You must factor this out in determining which tank is better.

TomT

Crew quality and operational/tactical maneuver play a great role.

That truly is the bottom line. As in the France '40 example, many of the German Panzers were Mk.Is. Armed with only 2 MGs … But they [along with the Pz.IIs, IIIs, 38Ts and Pz. IVs] out maneuvered the less tactically proficient French and British forces. If you look at the inventory of AFVs comparing the German vs. French/Brit. The Germans were inferior not only in numbers but quality … The Pz.IVs[with short barreled 75] were few and far between. Rommel's 7th Panzer Div had mostly the Czech designed 38t …