Of rotating hulls, Panthers and CM2.

[kipanderson]

Hi,

When it comes to the continuing firefight regarding the merits, or otherwise, of tanks rotating their hulls I thought I had better take Steve’s advice and give the feature a full test drive before giving an opinion. Of course, tanks are vulnerable whenever they expose their flanks and this can happen in any terrain. However, it has long been my view that the more open terrain of the east will lead to an increase in causalities amongst attacking AFV once we move on to CM2. This was reinforced recently when I bought the book The Battle of Kharkov, by Jean Restayn, and viewed the pictures there in. Superb picture after superb picture of the undulating terrain of Russia and the Ukraine. (For the “look of Russia” during WW2 this book can have no equal. It has to be said that they are all winter pictures.) The reason I think causalities will be higher is that the broken terrain of Normandy and the Ardennes often protects the flanks of attacking AFVs. If you are attacking through the wooded terrain of the Ardennes you have to protect your flanks against short-range fire but often the nature of the terrain means there is no risk of long-range anti-tank fire from your flanks. In the east this is not the case. When playing CM I normally play with a map about 800m-1000m wide and 1600m-2000m deep. When I move on to CM2 it is my view that the maps will have to be wider to fully represent the possibility of long-range flanking shots, that there is no real “cut off” to the terrain on the flanks. Looking at the pictures in the Kharkov book it is clear that this will often have been a problem. So, given that the rotating hull question is really a flanking shot question I thought I would model a quick and crude representations of “typical” eastern front terrain, if there is such a thing. I also went for a type of anti-tank gun with a penetration typical of Soviet guns that may have made up the famous “PAK fronts” that Germans always refer to. I went for the US 57mm gun. This has a penetration slightly greater than the 76.2mm M1942 Soviet gun but slightly less than the 57mm M1943 Soviet gun. A good representation of the “average” penetration of Soviet anti-tank guns during the second half of the war. When it comes to the type of tank to use in my test it had to be the Panther. The reason being that I wanted to use a model with heavy frontal armour but light side armour to fully show up the effects of flanking shots. At a range of 500m or more the US 57 gun could not penetrate the side armour of the Panther when fired from anywhere between 11 o’clock on one flank and 1 o’clock on the other, 12 o’clock clearly representing the front of the tank. Its only when you get out to angles of attack from around 10 o’clock and 2 o’clock that the 57 gun can penetrate the side armour of the Panther as these sorts of ranges.

There were twelve Panthers and a company of armoured Panzer Grenadiers on one side and nine 57 guns together with a company of infantry on the other. The map was 1600m wide by about 900m in depth. Along the northern 1600m edge there was a large amount of woodland with a road running from north to south through the middle. Other than that the map was largely, but not totally, clear. We are talking about a caricature of Russian terrain. Around the road on the northern, wooded map edge there was a cluster of “objective” flags to give the attacking AI something to aim at. The nine anti-tank guns were set up on the edge of the woods in three groups of three. One about 250m in from the western and eastern map edges and one in the centre. The German kampgruppen was set up within 200m of the centre of the southern edge. I played the Russians/US in order to ensure that I opened fire from 10 o’clock first so as to observe the extent to which the Panthers would rotate so exposing their flanks to the “main direction of the threat”.

When the advance got under way the AI sent 4-6 Panthers straight up the road towards the objectives. The advancing tanks were unbuttoned and “looked” as though they were in hunt mode, but who knows. The other Panthers took up covering positions with the half-tracks a little way behind. Could have come straight out of a US Army Field Manual, a credit to Charles and the entire team. When the lead Panther was within about 300m of the woods I opened fire with a 57 gun from 10 o’clock, all other “Russian” forces being covered by a “hide” command. The lead Panther was knocked out with the second round. The surviving Panthers, in column formation behind the lead tank, but correctly spaced, rotated their hulls to 11 o’clock and their guns to 10 o’clock. Within the space of 30 seconds the action was over, the 57 gun destroyed and the Panthers rotating back to face the objectives and continue their advance.

For the next turn I ordered the two remaining 57 guns on the Panthers left flank, at between 10-11 o’clock to open fire. Two more Panthers were knocked out and once again the remaining Panthers rotated towards the 57 guns. By the end of the turn only one of the two 57 guns remained but some half a dozen Panthers had rotated to face the surviving gun, some having rotated “all the way” so that their hulls were facing 10 o’clock, not just their turrets. At this point I opened up with the anti-tank guns at both 12 o’clock and 2 o’clock. Mass slaughter resulted. By the time all the anti-tank guns were silenced a total of nine Panthers were destroyed. By the time the last anti-tank gun was being destroyed the AI kicked in as impressively as it had started. The three surviving Panthers went into reverse, keeping their hulls facing more or less at the centre of the “threat” area. They took up covering positions. The remaining half-tracks, about 9 out of the original twelve (I had culled some in the editor), took up position behind what little cover they could find. The Panzer Grenadiers disembarked and began a textbook assault. At this point I ended the game.

The fact that the Panthers took heavy losses within the “perfect kill zone” of the PAK front will be a surprise to no one. The question is, did the new “rotating hull” tweak lead to heavier casualties.

If a Panther was advancing straight up the road towards the objective and fire was received from the direction of 10 o’clock what tended to happen was that the Panthers would rotate their hulls to 11 o’clock and their guns all the way to 10 o’clock so as to engage the threat as quickly as possible. If the threat did not die quickly, the Panthers would rotate their hulls further, all the way to 10 o’clock. They tended to behave like this even if there was fire coming from multiple directions. So even after the entire PAK front was ablaze along its complete length the Panthers tended to rotate their hulls towards what ever threat they had “locked” on to, until that threat was destroyed. In doing this they were disregarding threats at 12 and 2 o’clock and paying a heavy price.

I played two games. In the first nine Panthers and three half-tracks were lost. In the second ten Panthers and five half-tracks were lost. I used identical tactics in both.

A reasonable question would be “what would the likely casualties have been without the rotating hull tweak?” They still would have been heavy.

Firstly, if the 57mm guns opening up from the extreme flanks, 10 o’clock on one side, 2 o’clock on the other, they would still have been able to penetrate the hull sides of the Panthers. Its difficult to estimate, but in my view, between 2-4 tanks would still have been lost due to this fire from the extreme flanks. Probably not more due to the fact that once a given anti-tank gun opened up it did not last long. But Panther losses would have been higher still, even without the tweak, due to what I always think of as “the” weakness of the Panther.

This weakness is the critically thin turret side armour. 45mm at 25 degrees slope was not enough by 1943; in fact by 1942 it was not enough. To take an example. Imagine a Panther advancing somewhere on the eastern front in late 1943. It swivels its turret to engage a target at 1 o’clock. If even a lowly Soviet 45mm M1942 gun then opened fire from 11 o’clock, relative to the facing of the hull, the Panther’s turret side armour could be successfully penetrated out to a range of about 600m. If the attack came from further out on the flank, say 10 o’clock, or a more powerful gun was being used, the range at which the Panther is vulnerable to such fire greatly increases.

In short, even if the new rotating hull tweak had not been made some Panthers would have been lost due to turret side armour penetration as the tanks engaged targets on their flanks. The turret sides of the Panther are a “lot” smaller than the hull sides but, in my view, 1-3 tanks would still have been lost that way.

If the tweak had not been made I estimate that between 3-7 Panthers would still have been lost. This would have been the case even if one takes into account the fact that the rotating hulls allowed marginally quicker engagement of anti-tank guns on the flanks. You are exposing a “lot” of side armour in return for only a small increase in speed of engagement, in my view, but it is difficult to quantify.

With the tweak tanks fight in the same style as assault-guns. As a result, in attack, especially over open ground, they suffer heavier losses than before the tweak. If the direction in which a tank points it hull was “reasonably sticky” to the direction of advance, it uses its turret rotation to engage flank targets, losses would decrease. Remember that every 60 seconds the player can intervene to “manually” rotate the hull.

As far as I know it is very rare for Steve, Charles and the gang to get things wrong. However, on this occasion my vote would go for a return to the “pre-tweak” hull rotation AI.

Thanks for your time,

all the best,

Kip.

PS. Sorry to have been so long winded.

PPS. To put things in perspective the turret side armour of the T34/85 was 75mm, of the JS2 95mm. The JS 2 weighed the same as the Panther.

[This message has been edited by kipanderson (edited 01-17-2001).]

[:USERNAME:]

I believe the germans hung tracks on the side of the panthers turrets and that this would help. The panther tracks are pretty thick and would add some amount of protection. It must have become SOP at some point.

The sov tanks could have more side armor because of the lighter engines used in their tanks.

[Vanir]

Nice post as usual Kip. I think this got buried in all the hoopla surrounding the German points change.

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You've never heard music until you've heard the bleating of a gut-shot cesspooler. -Mark IV

[PzKpfw 1]

Good posy Kip thats exactly why PzKpfw IVs were generaly used as flank protection for PzKpfw V's.

Regards, John Waters

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"We've got the finest tanks in the world. We just love to see the

German Royal Tiger come up on the field".

Lt.Gen. George S. Patton, Jr. February 1945.

[Vanir]

Originally posted by PzKpfw 1:

Good posy Kip thats exactly why PzKpfw IVs were generaly used as flank protection for PzKpfw V's.

And they also used Pz IIIs as "tenders" for the Tiger in its early days.

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You've never heard music until you've heard the bleating of a gut-shot cesspooler. -Mark IV

[kipanderson]

Hi,

:username,

Yes, at some point I am sure that the use of tracks on the side of the turrets became SOP. Probably very early on, tank crews were only to well aware of the strengths and “weaknesses” of the models they served in, from what I have read. I have just had a quick look in one of my books, one of the excellent “Armor at War Series” from Concord, and in there only about 20% of the Panthers have tracks on their turret sides. By the second half of the war the Germans were short of everything.

Vanir,

Thanks for the kind comments. Just thought a CM2 style test for the tweak would be fun. And it was. I sometimes worry about the extent to which I enjoy watching AFVs getting knocked out in the one-minute CM movies. Clearly some sort of mental disorder!

John, Hi,

Yes, the I have read that the Germans adjusted their usual attack formations as the war went on. The usual “keil” or wedge, became more of a flattened “bell” shape because the guys at the point of the wedge were being knocked out too easily. If I remember correctly.

By the way I hope my post did not sound too critical. It is very, very rare for Steve and Charles to get things wrong. But in this case I feel they may have. I still feel the best solution would be for the direction in which a hull faces to be “sticky to the general direction of advance”. To generally only rotate of away from the direction of advance if ordered to by human command, or to find a rout round an obstacle. Of course, assault-guns are different matter. (I probably have not expressed my self too clearly but I hope people understand what I am trying to say.)

All the best,

Kip.

PS.Yes, they did use PZ IIIs as "tenders" to the Tigers in the early days. Problem was the PZ IIIs got shot to pieces because they could not "stand the heat" in the same tactical situations as the Tigers.

[JoePrivate]

"German Advance to the Resseta River" July 1942 from Small Unit Actions during the German Campaign in Russia.

"When the 19th Pz Div attacked northeastward from Kholmishchi, the forward armored elements ran into strong Russian AT defenses south of Nikitskoye. In devising their defense system, the Russians had taken full advantage of the concealment offered by the terrain and vegetation.

One German armored column drove straight into an AT gun front disposed in a semi-circle facing south.The Russian guns, emplaced in pairs for mutual support, were dug-in so the muzzles were just above the surface of the ground. Between each pair of guns was an additional AT gun mounted on a two-wheeled farm cart. The cart-mounted guns were camouflaged but no effort was made to conceal them.

As the German tanks advanced, the dug-in guns fired a volley then ceased. Seeking the source of the fire, the Germans noticed the guns mounted on carts and moved toward the newly discovered targets. As soon as a German tank turned to bring the cart-mounted guns under fire, it was hit from the side by Russian AT fire from the concealed positions. The cart-mounted guns were dummies. Several tanks were lost in the action before the Germans succeeded in knocking out all the real AT guns. In emplacing the dummy guns, the Russians were careful to leave just enough of the gun visible to make it an attractive target. Taken in by this ruse, the Germans turned their tanks to face the decoys, thereby exposing tracks and lateral armor, the most vulnerable parts." (italics mine)

[kipanderson]

JoePrivate, hi,

Great find.

I have the same book, best of the series on the Eastern Front produced by the US army in the 50s, in my view. Shame there are not more accounts from the second half of the war. 80% are 41/42.

Goes to show PAK fronts happened. Life was tough on the Eastern Front. I remember reading a number of times that the Germans rated Russian defence and camouflage as their strongest points. Your great extract illustrates this very well.

All the best,

Kip.

[engy]

Wow, Kip...good work, and a very clearly written post. Well done.

Whether I agree with your conclusion ("put it back to the old way") or not is somewhat irrelevant to the point I would like to make: There have been several "home-grown" scenarios reported on in the last few weeks to either prove or disprove the success of the new hull-turning algorithm. Unfortunately, that is the problem: I can create a valid, historical-like scenario and if it reinforces my argument, I publish it. However, someone else can create a scenario that is just as valid and historical-like and it might come to the opposite conclusion. (I believe it was Bullethead who published scenario results right after the furor broke out 'proving' that the new way is better.)

For example, let's take your scenario and modify it a bit:

Scenario: AT gun at 11 o'clock opens up first.

Possible response of tank:

Method A. Turn turret only to engage.

Method B. Turn turret and hull (completely) to engage.

Let's examine both methods under 2 different conditions, taking your assertion that the AT gun is possibly/probably lethal when firing from the Panther's 10 or 2 o'clock position.

Condition A: Another AT gun at 1 o'clock then opens fire. Obviously, Method A is better, since the front of the hull still obliquely faces both targets. Method B is likely to result in a dead Panther.

Condition B: Another AT gun at 10 o'clock then opens fire. Method A now possibly results in a dead Panther, but Method B has the hull front obliquely facing both targets.

(And no doubt, we could go on all day rearranging the AT guns to favor 'A' or 'B'.)

So, which is better? I think it completely depends on the situation. There are other factors involved (eg, the "hull-turning method" brings the gun to bear more quickly) which add another layer of information to be dealt with.

To sum up, I am not sure that isolated cases, no matter how carefully designed and tested, are able to prove the argument one way or another.

engy

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"He who makes war without many mistakes has not made war very long."

Napoleon Bonaparte

[John Hough]

Something you're forgetting here is thet the really dangerous behavior, fully turning the hull to face the flanking AT gun, is NOT new. Tanks have always turned their hulls to face a sufficiently threatening target shortly after engaging. The difference in tank behavior is that the tank will now turn the hull to 11 o'clock and the turret to 10 o'clock, rather than just turning the turret, in the inital move to bring the gun on target.

You might want to load up an older version of CM, and see what hapens in the scenario. I have a feeling that the panthers will probably be worse off, as they still expose the turret sides to threats while aiming, and the delay in firing caused by turning only the turret will let the AT guns get more shots in.

-John

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sometimes i'd like to kick your f-ing head

but i guess you're just a human too

-EMBRACE, "SAID GUN"

[kipanderson]

Hi,

engy,

Lots of good points and, yes, basically I agree with you. In my defence I would just make a couple of counter points to clarify what I was trying to say.

Firstly, I did set it up as a real “test” not just as a way of proving a previously held opinion. Of course, I did suspect that the causalities would be heavier as a result of the tweak, as I imply in my post. However, it was a real experiment to find out how PAK Fronts would now be handled. It was like being back in school when you were doing an experiment, which was hugely good fun to do, and you did not have much of a preference as to how it ended.

Secondly, I agree with you that under Condition B, a second AT gun opens from 10 o’clock, the first having opened up from 11 o’clock, the rotating hull tweak is a help in “reducing” likely causalities. It will sometimes happen that a hull is turned to 11 o’clock and then a threat “even further out on the same flank” opens up.

However, one of my assumptions, which I should have clarified, is that the “main threat” or the “area mostly to contain AT weapons”, however you wish to think of it, is roughly in the direction of the objective. Imagine a situation in which a commander is given the order to “take that village”. In CM terms “that village” would be more or less in the middle of the second half of the CM map, viewed from the line of departure. It is also likely, but not certain, that both in the real world and in CM, the village would have the greatest concentration of enemy. I believe this would be known, or assumed, by both commanders and tank crew. In such a situation I believe, but do not claim to “know”, that tank crews would do their utmost to resist exposing their side armour to the objective village. They would know all to well that to do so would mean likely death. Against this there would be the temptation to turn the hull to face an immediate threat on the flank. But if they held their nerve, and did not rotate their hull, they would be most likely to survive.

To me the advantage of a tank is that it can keep its hull pointing at the “main threat” and deal with threats on the flank by turning its turret. Assault-guns cannot do this and therefor suffer heavier casualties in attack.

It is one of those questions to which there is no perfect answer.

John, hi,

I admit that I do not remember the detail of hull rotation in 1.05. It would be great to load it up and have a go at my scenario, but I deleted it away and empty my recycle bin regularly. Just looked, it has gone.

All the best,

Kip.

PS. Is there anywhere one can get hold of 1.05?

[Vanir]

Originally posted by kipanderson:

PS. Is there anywhere one can get hold of 1.05?

ftp://ftp.battlefront.com/pub/patches/cm105.exe

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You've never heard music until you've heard the bleating of a gut-shot cesspooler. -Mark IV

[This message has been edited by Vanir (edited 01-25-2001).]

[tss]

JoePrivate wrote:

The cart-mounted guns were dummies.

That story brought into my memory a similar story but on different topic. I don't know whether this is true or not. I read it from Miihkali Onttoni's memoirs where he stated that one Ukrainian POW had told it to him.

This happened in early January 1940, shortly before the Soviet 44th Infantry Division was encircled on the Raate road. One morning someone of the Ukrainian guy's platoon noticed a Finnish sniper that had climbed to a tree. The men then quickly took cover and started to fire at the sniper. After a short while two of them rose up, convinced that the sniper was dead, and walked towards the tree. Two quick shots. Two dead Ukrainians. They then continued firing at the tree, firing most of their ammo before stopping. One man rose and advanced carefully towards the tree. A quick shot, one dead more.

This time they brought machine guns and fired several 250 round belts at the sniper. However, it took a long time before anyone dared to go to the tree. When the first one got near it, he noticed that the only thing in the tree was a bullet-torn snow-smock. The sniper had been behind a rock about 10-15 meters from the tree.

As I mentioned, I don't know whether this really happened or did the POW invent the story himself. Onttoni himself was an East-Karelian refugee who had come to Finland after the failed Karelian independence war. Since he spoke perfect Russian (and, of course, Karelian) he spent some time in POW camps interviewing the prisoners.

- Tommi

[kipanderson]

Hi,

Vanir,

thanks a lot for the information.

Its a big help.

Tommi,

Very interesting little story. Shows just how dangerous real war is.

All the best,

Kip.

[kipanderson]

Hi,

I owe Steve and Charles an apology. I was making too much fuss about a tweak that changed very little.

I have now had the opportunity to test the same game, using the same tactics, in both 1.05 and 1.1 versions. The result is that using my PAK Front/Eastern Front scenario there is very little difference between the two. Using version 1.05 the average loss was 8 Panthers, using 1.1 it was 9 Panthers. This was over a test run of six games using each patch.

As has been pointed out by others, after a short delay the attacking Panthers turned their hulls all the way to 10 o’clock even when using the 1.05 patch.

What this has done is focus my attention on the issue of rotating tank hulls in a way that had not been the case before version 1.1.

It is still my view that “stickiness” to the direction of advance would reduce losses further. That tanks do fight rather too much in the style of assault-guns. However, maybe they did this in reality?

I own guess is that in reality there will have been a reluctance to turn a hull front away from the “main threat” because if the crew managed to hold their nerve in the long run more would survive.

The problem remains that the AI is not good at judging where the “main threat” is and therefor a reluctance to rotate away from the direction of advance may be the best answer.

As with most questions regarding CM there is no perfect solution.

It was fun doing the tests and it has increased my appetite for CM2 even more.

All the best,

Kip.