Sunday, 13 October 2013

Tiger Vs T-34 system analysis


Tactical gamers are generally aware of the handling and capabilities of key vehicles such as the German Tiger I and the Russian T34/76 tanks in their rules and in historical accounts from the period. This article is just intended to show how Lock ’n Load deals with these two adversaries, so that gamers can compare this to their own systems.

At the conclusion of the article there is a link to a fascinating source for gun / armour penetration tables (the introduction alone is valuable).



One of my vehicle drawings for a home grown tactical game.



In 1941, the Germans had been shocked at the capabilities of the new T-34 tank that the Russians had just put into the field. It would be over a year before the Germans could put themselves ahead of the game, by introducing a new heavy tank that mated heavy armour with the 88/56 gun and being generally known as the Tiger I. Only available and used in relatively low numbers and by elite crews, this vehicle was able to destroy Russian T-34’s out to substantial distances (1500 - 2000 yards being possible engagement ranges).
For this early to mid period (including Kursk 1943), we are left with an impression of T-34 tanks dealing with the Tiger menace by racing towards them and opening fire at point blank range, deliberately going for vulnerable parts such as the track or trying to get into flank positions for shots at the weaker side armour and even ramming Tiger tanks!
So lets look at the Lock ‘n Load armoury.



The front face of each counter gives the following information. The numbers in the bottom left are armour values for the Hull / Turret. The first row is front armour, then side armour and finally rear armour. 8T and 11T are movement rates. The number in the circle is the morale value, the number in the square is the HE equivalent value from the main gun. The red 4 is the machine gun value (this is split as 2 + 2 if the turret is not facing towards the front).
On the rear of the counter is the ‘to hit’ table.



The top row indicates the various range bands. The second row is the ‘to hit’ number needed at the given range band and the bottom row is the penetration value. So at 16 hexes the Tiger would fire on the centre column, needing 7 or less to hit (on two dice) and if hitting then the penetration factor is 7.

The third column is not going to come into typical use because of the small battlefields and limited lines of sight that come from most scenarios. What generally becomes more critical is that point that a gun moves from the first column to the second as these gun ranges can be common to scenarios. In the above example, If the Tiger can sit away from the T34 at 7 hexes, then it will fire on the efficient 1st column, while any return fire from the T-34 would have to be calculated on its 2nd column.
 
Assuming that a hit has been made, then the basics of checking whether the armour has been penetrated is done by the attacker rolling a D6 and adding the penetration value shown on the ‘to hit’ table. The defender then rolls a D6, adds the defensive value of any terrain and adds the armour value for the face being struck. Those two results are compared. If the modified gun value scores higher than the modified armour value, then the vehicle is destroyed.
If modified gun and armour values are equal, further checks are made to see if the vehicle is either abandoned or goes shaken. If the gun scores less, the vehicle takes a morale check, but cleverly, that check is modified by the degree of failure of the shot to penetrate. So the better the armour performed, the bigger will be the favourable modifier to save it from going shaken.
There are modifiers to the ‘to hit’ process and some variables to the penetration calculation, but for the sake of our examples, we will assume that both vehicles are in the open and buttoned up and that all shots strike the front turret.
Situation 1.
Have regard for the game scale, which is 50 metres to the hex.



At 15 hexes (750 metres), the Tiger can operate on column 2 while the T34 is on column 3. The Tiger will hit the T34 (on a 7 or less) 58% of the time. The T34 will hit the Tiger (on a 5 or less) 28% of the time.

Once hit, the issue of penetration needs to be established. We will assume that all shots are hitting the front turret. At 15 hexes the Tigers gun value of 7 must defeat the T34’s armour value of 4. The best the Russians can do is roll a 6, making their armour value equal 10. To defeat this (i.e. knock out the tank outright), the Tiger needs to roll at least a 4 (making a gun value of 11). If the Tiger attack only rolled a 1, the T34 could survive an outright kill on a roll of 5 or 6 (added to their armour).
However as already mentioned, a 'no penetration' result then leads to further testing for the target to see if it goes shaken.
In return fire, if the T34 secured a hit on the Tiger, the best it could do would be to roll 6 (giving 9) and the Tiger would only need to roll 2 or more to defeat that.
I know the sum is actually 1 or more BUT, if a firer rolls a 6 and a defender rolls a 1, the penetration becomes automatically catastrophic (like a critical hit in other systems), so our Tiger does not want to roll a 1.
Things that can help the target - being in defensive terrain or moving helps reduces the ‘to hit’ chances.
Things that can help the firer - being open rather than buttoned up and having a leader helps the ‘to hit’ chance, as does the target staying still,so that the firer gets a target acquisition bonus on subsequent shots. The firer not moving or pivoting or traversing the turret prevents penalties on the firers ‘to hit’ roll.
The penetration values are fixed and only subject to the variables of the dice and whether the firer strikes a weaker or stronger part of the tank facing (hull or turret). The T34 turret is weaker than its hull, while the opposite is true for the Tiger (On the PzIIIj both front hull and turret are the same strength).
Situation 1 pretty much has the Tiger in the perceived role of dominating the field at range, with the T-34 either having to hide or move closer to the Tiger before attempting shots.
 
Situation 2.




In this situation, the T34 can now use the middle column, while the Tiger remains on the middle column, so results for the Tiger will be as above. The T34’s chance of a hit goes up from 28% to 42% and the penetration factor goes up by 1.

If the T34 rolls a 6 on penetration, it would still only knock out the Tiger if the Tiger rolled 1 (catastrophic hit) - though of course a morale check for the Tiger may result if the Russians rolled a 5 and the Tiger rolled a 2, but we are only dealing with knockouts here. So despite getting closer, the sums are much the same.
Situation 3


This situation is quite critical and potentially common as tanks frequently find themselves on the cusp of columns one and two. At the 7 hex range, the Tiger uses column 1 and the T34 is still on the middle column. It is fair to say that what was already a good situation for the Tiger, has just got better and this is an ideal range to use opportunity fire against a moving T34, as a hit becomes more certain (on a 10, minus 1 for a moving target).

Situation 4.


The T-34 now gets to use column 1. This is as good as it gets, unless it can get into a flanking position for better penetration against flank armour, or get adjacent for a +2 bonus on the ‘to hit’ roll, though that will not help the penetration outcome.

At range 6, if the T34 rolled a 6 on penetration, the Tiger would need to roll 4 or better to avoid a KO, so things are getting better for the T34, but it is still a little luck reliant and I would prefer to have more than one T-34 in the area to increase the likelihood of a Tiger KO. Getting a hull shot would help and a flank hull shot would always penetrate if the Russians got a 6 and would still have a 50 / 50 chance of penetrating if they only rolled a 3.
So in conclusion, the notion that in a head on assault without cover, the T34’s would have to attack in numbers to swamp a Tiger and get up really close to stand a real chance of knocking it out (or use good field craft to get into flank positions), seem to be reflected in the values that the game gives us.
Just to cross reference these outcomes with a different tank gun, lets look at the T34/85 with the 85mm gun. In reality, this could typically be expected to harm a Tiger frontally at ranges up to around 500 metres, or 10 hexes in our game (note most gun tables use 500 metres and multiples thereof when calculating gun efficiency, but L’nL is doing something else, probably to work with our compressed battlefields).
Here are the gun stats for the T34/85.


The To Hit values on the German gun are significantly better at the closest ranges (91% chance of a first time hit compared to 72% for the 85mm). Official observations show the 88 as being very accurate, with 100% hits at up to 1000 metres during tests.

Likewise, the penetration values of the German gun are notably better (I didn’t think that ballistically they were that far apart), though the question is simply whether this upgraded version of the T34 is more able to take the fight to an enemy Tiger tank.
Image added again for readers convenience

The first column of the 85mm is representing fire at up to 350 metres. If they roll a 6 (making 12) against the Tiger front turret, the German will need to roll 5 or 6 to defeat the shot from being a knock out and if it survived, any morale test for ‘shaken’ (like broken in other systems) would receive a detrimental modifier, making the Tiger potentially vulnerable to all such shots.
If the T34/85 rolled 4 (making 10), the Tiger would need to roll 3 or more to survive a KO. A hull hit though would increase the chance of a kill.
At a range of greater than 7 hexes, the 85mm gun does not perform any better than the 76.2mm on the earlier T34, which is surprising to me at least.
As with most guns, the 85mm had small rations of special ammunition that made a noticeable improvement to performance. Special ammo does not feature in the system, something that I assume falls out of the variable that comes with the D6 when penetration is calculated.
So the T34/85 does give us a vehicle that feels less impotent than the 76, but only at the closer ranges, which seems to accord with the historical accounts.
The link at the bottom of this article suggests that a Tiger I can take out a T34/85 at 1400 metres (penetrating 75mm), while the T34/85 can KO a Tiger (penetrating 110mm) at 500 metres (that doesn’t always mean it will, but the range of probables start there).
Looking at the To Hit tables on the back of the vehicles, the 85mm looks quite underpowered compared to the 88/56, the gun tables that I have looked at suggest a smaller difference than shown here with basic ammunition. However, in terms of translating real world narratives into how the game plays, then things do feel right and the gun / armour relationships seem to work well.
The SU 152 Tank Hunter counter (not shown here) has a penetration value of 8. It is known to be able to take a Tiger I out from any direction and that 8 value would allow that, subject purely to the variables of the dice. So again, this is another vehicle that seems to fit in nicely with expected outcomes.
When trying to work out gun / armour values in games, it is too easy to become fixated on gun tables alone. The angle of shot to armour facing, quality of armour, different ammo types and elite nature of Tiger crews etc, all add something to the pot and the D6 variable seems to take care of that nicely.
T34/76 from my 10mm collection.

Part of the picture that has not really been shown here, is that once hit, even though a target might not be penetrated to cause a knock-out, it will be subject to a morale check and a failed check (shaken) can put a tank out of action for as many turns as it takes to self rally. So all those ’non-penetration’ results mentioned so far, could in fact result in something just as effective as a knock out.
An example of this would be - a T34/76 starts the turn parked in light woods, facing a Tiger I on open ground just 5 hexes away. The Russians have won the initiative for the turn and will go first. They fire at the Tiger, needing 8 to hit. There are no modifiers and they roll 7, so they have hit. An odd number means they have hit the Tiger's hull.

Now to check for penetration. At this range, the T34's penetration value is 5, they add that to the roll of a d6, say they roll 4 (4+5=9). The Tiger's hull armour is valued at 7. The German player rolls a d6 and adds it to the 7. Say they roll a 3 (3+7=10), there is no terrain modifier to add because the Tiger is in the open.

The T34 gun has not penetrated the armour (9 versus 10), the difference between those two scores is ONE in the German favour.

The Tiger must now take a morale check. It rolls two dice (lets say scoring 8), and DEDUCTS the gun / armour difference that has just been calculated above (ONE in this case), reducing the morale check roll to 7. Compare the result to the Tiger’s morale level (6 is on the front of the counter). This would mean the tank had failed it’s morale test and would go ‘shaken’, so you can see that even though a penetration does not occur, fairly common rolls can still lead to harm once a hit has been obtained.
If the Tiger had rolled a 5 instead of a 3 on the penetration roll, then the difference between the T34 gun value and the Tiger armour value would have been even greater (T34 remains 9, the Tiger becomes 12), the difference would be THREE and that '3' would have come off the moral check roll instead of the '1' that we had to use above and in those circumstances, the Tiger would then have passed the Morale Check. I love the way the system does this, it is great 'design for effect'.

This adds another variable into the gun / armour outcomes and collectively, they make for an exciting game as you can never take anything for granted as either the defender or attacker.

Having delved into the subject a little, I remain pleased with the way that the Lock ‘n Load system handles anti-tank fire. It is a complex area of warfare that has been kept simple and effective in the game.
Here is a link to a fascinating source for armour penetration tables, well worth book marking.
LINK - http://mr-home.staff.shef.ac.uk/hobbies/ww2pen3.pdf