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A few more random pics from the beta. Feel free to ask questions about anything that interests you.

Some Panzer IIINs

And the specs screen for the Panzer IIIN:

This Soviet 45mm ATG has a flank shot on some Panzers, but accuracy at that range is a bit of a challenge.

The ubiquitous T-34...

The somewhat less common KV-1. This one can still be quite a pain for most German tanks in Late 42. This is also a shot of one of the "purchase" screens for a set battle, where I'm choosing from the available force pool which forces I want to bring to the fight.

Is the Star over the unit symbols meant to represent a leader unit? HQ?

Is the hit location and hit cahnce based on a two-die system like the old Tobruk game?

Yoozername,

ORIGINAL: Yoozername
Is the Star over the unit symbols meant to represent a leader unit? HQ?

Yes, that represent an HQ unit of one sort or another.

Is the hit location and hit cahnce based on a two-die system like the old Tobruk game?

Locations 11 and 12 are not normally accessible (only vs. fire at the vehicle's Top), so it's normally a d10 roll for hit location.

Regards,

- Erik

Still a very flat landscape.

All the best

Andreas

Errr.. does the "to hit" chance depend on a virtual dice to be rolled?!

If so, what other factors are determined by dice rolling?

If I understand Erik correctly the d10 roll is only for the hit location, not the hit probability. Although what can actually be hit should of course be dependent on the direction of the shot, relative to the target.

All the best

Andreas

Hi all,

A few answers:

First, Andreas - yes, the terrain is flat. It actually was very flat, but there are some maps with rolling areas and others with some frozen river gullys.

Second, on how vehicle combat works...

Yes, the "to hit" is also a roll, as is "to penetrate". The combat engine is realistic, but not hyper-realistic. So, this is not a Combat Mission or a Tank Sim, but more along the lines of a Close Combat or East Front in terms of the level of detail and the types of calculations.

Let me give you a detailed example of what goes on under the hood, let's take a PzKfwIVF2 firing at a T-70 at about 500 meters with APHE ammunition and we'll also look at the T-70 firing at the PzKfwIVF2. We'll assume both crews are Veteran, since experience can affect various things in these calculations and Veteran is the "default" (no modifiers) level.

PLEASE NOTE: The game does all this for you once you tell one tank to shoot at another, but I want to give you an idea of what it's taking into account.

We're just going to do a single shot here, though rate of fire is also modeled, as is turret speed. We'll just assume they're both facing each other head on. We will also assume they have sighted each other, which is not a given as there can be vast differences in your sighting range and effectiveness based on what your tank is doing and what the other tank is doing. For example, a PzKfwIVF2 rushing forward would almost certainly be shot at by that T-70 before it realized the T-70 was there.

Ok, now let's say the PzKfw IVF2 shoots its first shot at the T-70. First, the 75mm/L43 has a To Hit number of 5 at 500 meters. It's almost a sure hit inside of about 425 meters, but the difficulty starts to climb after that. So the base roll to hit is a 5 or more on a d10.

Since this is the first shot at a target over 300m away, that's modified up to a 6. The T-70 also has a size modifier of 1 (it's a small tank) which makes this a 7. There are no modifiers for previous shooting, for either tank moving or for shell type (HEAT and HE are less accurate), nor are there modifiers for cover in this case. We'll say the Panzer already turned its turret the previous phase, so no penalty for that either. So, basically, we have to roll a 7 or more on a d10 to hit with our first shot, which gives us a 40% chance. After the first shot, this goes up to a 50% chance. Once we actually score a hit (any hit) on the target, this goes up by another 10% to 60% as it's considered to be an "acquired target". If we were shooting at the side rather than the front there would also be a bonus. Note that the "to hit" roll is open-ended, so a result of 10 has a 50% chance to end up being a 11-15, which allows "lucky shots" to happen (i.e. driving forward, turret turning, snap shot at 500m, ping! - highly unlikely, but possible . Anyway, let's say we hit.

The penetration for the 75mm/L43 at that range with APHE is a 10 (it has a value of 10 from >450m to <=625m). That's a nice penetration value! We use the front location chart here (note that there are also changes for things like side deflection shot, etc. which is calculated based on the angle of the shot and can lead to multiplying the effective enemy armor if you are at a poor angle). The T-70 does not have shabby front armor though. Its hull is a 7 (sloped) in 3 of 5 Hull locations, the other two Hull locations are Armor 4 and the three turret locations are one 4 and two 4 (rounded). We also have two Track locations with 1.5. The location for the hit works like this - you look at the side you are hitting (the front) and roll a d10. Let's say we hit the best armor on the T-70, the 7 Sloped Hull armor (30% chance to hit that with a front hit).

Now the game looks at the ammo type. It's APHE. We compare it to the armor type (sloped) and roll to see what the _actual_ penetration value is, starting with our base of 10. This is also an "open ended" roll, so you can get "critical hits" that penetrate more than they would normally be able to. In this case, there is about a 33% chance of normal penetration (10), a 16% chance of penetration 9, 16% chance of penetration 7 and a 33% chance of penetration 5 (this would be the only non-penetration, if you get below the armor value the shot bounces off). There's also about an 8% chance of a critical penetration, which could go anywhere from a 11 penetration up to a 20 effective penetration once all is done (about a 2% chance for the 20).

So, there's about a 33% chance of a non-penetration once we hit the T-70, provided we get the best armor location and roll the worst penetration result. Let's say we get a penetration of 9. This goes through the armor in this location, so we penetrate and have to roll for effects.

The 75mm/L43 APHE has a "D"estruction rating of 6 and a "S"tun rating of 10. On any hit, even if it deflects, this means there is a base 10% chance to stun the target vehicle (roll a 10 or more on a d10). In the case of the T-70, as a light tank it gives a +1 to our Stun roll. If we actually damage it, that adds another +1 to the roll. The "D"estruction value is what we check against to see what a penetrating hit does once it gets inside the vehicle.

In this case, we've penetrated the Hull Front, so there are two damage results possible. The first is destruction of the vehicle. The second is Mobility damage (kill the driver, wreck the steering, etc.). For each one, we roll a d10 and try to get equal to or greater than the value for the shell, which is a 6. However, since our penetration exceeded the armor (by 2 in this case) we do get a +1 to this roll. In effect, we have a 60% chance to knock out the T-70 and a 50% chance to destroy its mobility. If both chances fail, the shot had no real effect (other than the Stun chance).

So the net effect for this exercise: PzKfwIVF2 had a 40% chance to hit on its first shot, a 66% chance to penetrate if it hit the best armor on the T-70 and a 60% chance to destroy the T-70 in our example.

Now, let's say we did no damage at all and we failed to stun the T-70. So, the T-70 shoots back. Realize the odds are stacked against this little tank, but we'll try.

The Soviet 45mm/L46 with AP ammo has a base to hit of 8 at 500 meters. As with the Panzer, this is modified to a 9 because this is the first shot. However, the PzKfwIVF2 is not a small target, so there is no additional penalty to hit for size. Again, no modifers for movement, etc. due to how we set up this example.

So the T-70 has a 20% chance to hit. Let's say it hits, just for this example.

The penetration on its AP round is a 4 at 500 meters.

The Front of the PzKfwIVF2 has six locations with 5 armor, one with a 6 armor, two with a 2 armor (tracks) and one with a 9 sloped armor (part of the Hull). This means that unless the T-70 rolls the 20% hit location chance to hit a track, its AP round is very likely to bounce off. Let's say it hits a 5 Armor location on the Turret. It would need to roll a Critical Penetration (8% Chance) to get through. Let's say it does that and ends up just barely penetrating (penetration 5). The "D"estruction number for its round is a 7 and since it didn't over-penetrate, it gets no bonus. The "S"tun number is a 12, making it very unlikely to stun as well. If it penetrated the turret though, it could have a chance to destroy the Panzer, disable its main gun or kill the tank commander. Chances are it would get one of those results, since it has a 7+ on a d10 for each one. But in this case, hitting and penetrating at 500m is the toughest part as the T-70 is really outclassed in this duel.

Anyway, I hope that explains things better. Back to work...

Regards,

- Erik

It appears that hit location is broken up into ten 10% locations unless there is a height afvantage.

One of the most annoying characteristics of the CM hit location system was the generic odds of hitting parts of a tank. This made some of the most common vehicles vulnerable as turret hits were so much more frequent than they should hsve been. The best example is a panzer IV. Its 50mm turret armor almost always takes hits. In reality, the area is quite small and there is a gun mantlet that protects the area to a degree.

Unfortunately, it seems this game will do the same thing.

Tracks are very narrow on some vehicles. They are very wide on vehicles like the T34. To equate them is incorrect. I suspect that a + modifier will be used for hull down vehciles 'covering' the lower track hit/lower hull results.

Yoozername,

You are correct that we are not aiming for "more realism than CM" as a goal, but with that said we feel the results from this system end up stacking up very well against other current and past tactical wargames.

In the case of the Panzer IV, for example, there is an effective 30% chance of hitting the turret, whereas for something like the King Tiger (note, the King Tiger is not in this release), the chance is about 40%. If we were doing a first person tank sim, I think we would want to get more resolution than that, but the end results are pretty realistic for this scale of wargame.

Track hits mean a hit in the area of the track and the wheels that could at a minimum cause something to go off kilter. Note that a destruction roll is also necessary here to actually cause damage if penetrated and the chance is somewhat decreased.

Regards,

- Erik

Actually the hit location IS more realistic in that a PzIII shows 3 turret locations, one seems to have more armor (mantlet?). A similar treatment can be done for the PanzerIV I hope.

I just read the hit probability system you described. I can point you towards some excellent posts by rexford (as well as myself) where actual battlefield data, historical training test requirements (what a panzer guy had to do to pass) and statistical analysis are used to come up with some excellent results.

I do expect a game at this scale to handle gun accuracy in a non-abstract way. My initial impression is that your hit percentages are very low. A German 75mmL43, given even a poor initial range estimation, would have a much higher hit percentage than you describe.

ORIGINAL: Yoozername
Actually the hit location IS more realistic in that a PzIII shows 3 turret locations, one seems to have more armor (mantlet?). A similar treatment can be done for the PanzerIV I hope.

Actually, yes the mantlet is considered in that sense. On the Panzer IV, two of the three turret locations have 5 Armor, the third one has 6.

I just read the hit probability system you described. I can point you towards some excellent posts by rexford (as well as myself) where actual battlefield data, historical training test requirements (what a panzer guy had to do to pass) and statistical analysis are used to come up with some excellent results.
I do expect a game at this scale to handle gun accuracy in a non-abstract way. My initial impression is that your hit percentages are very low. A German 75mmL43, given even a poor initial range estimation, would have a much higher hit percentage than you describe.

I'd be happy to look those over.

Regards,

- Erik

I would be very happy to share those. I am assuming you know who Rexford is? He wrote a book about gunnery and such.

World War II Balistics: Armor and Gunnery" by Lorrin Rexford Bird and Robert D. Livingston,

rexford
Member
Member # 4402

You can do a search under member 4402 that is rexford


http://www.battlefront.com/cgi-bin/bbs/ultimatebb.cgi?

Battlefront.com Discussion Forums: Tiger accuracy

Battlefront.com Discussion Forums: Long range optics

Battlefront.com Discussion Forums: Theoretical Hit Rates Against Hulldown Targets

Battlefront.com Discussion Forums: Estimating Range With Gun Sight Triangles: Home Experiments

Battlefront.com Discussion Forums: What Tiger Vets Say About Range Estimation

Battlefront.com Discussion Forums: Hit Percentages with Bracketing: 75L48 and 75L70

After setting up a bracketing program on my computer, the following results were obtained for 75L48 and 75L70 APCBC against the front of a stationary T34 M43:

21 Guns Firing at 21 T34, Gun Stops Firing After a Hit
Program Stops At End of Fourth Round Attempts
Assumes Excellent Guns with Low Dispersion

1250m
=====

75L48

1- 4 of 21 shots hit (19%)
2- 5 of 17 hit (29%)
3- 8 of 12 hit (67%)
4- 4 of 4 hit (100%)

21 of 21 hit

75L70

1- 6 of 21 hit (29%)
2- 8 of 15 hit (53%)
3- 5 of 7 hit (71%)
4- 2 of 2 hit (100%)

21 of 21 hit

1500m
=====

75L48

1- 3 of 21 hit (14%)
2- 4 of 18 hit (22%)
3- 7 of 14 hit (50%)
4- 4 of 7 hit (57%)

18 of 21 hit

75L70

1- 4 of 21 hit (19%)
2- 6 of 17 hit (35%)
3- 6 of 11 hit (55%)
4- 3 of 5 hit (60%)

19 of 21 hit

2000m
=====

75L48

1- 2 of 21 hit (10%)
2- 3 of 19 hit (16%)
3- 4 of 16 hit (25%)
4- 6 of 12 hit (50%)

15 of 21 hit

75L70

1- 3 of 21 hit (14%)
2- 4 of 18 hit (22%)
3- 5 of 14 hit (36%)
4- 6 of 9 hit (67%)

18 of 21 hit

The initial range estimates had an average error of 20% from the actual range and followed a bell shaped normal distribution, from 0% error to +/- 49%.

The Germans required that crews be able to hit a target at 1200m-2000m by the fourth round at the completion of their training, which appears to be possible in most cases. If the initial range estimates were less than 20% in error on average the 75L48 would probably make it (+/- 200m would do it, which is extremely good estimating for 2000m targets and was not considered reasonable).

Any good game at this scale must have some system of estimating range. The Germans expected hits by the second round under 800 meters. They only tested trainees at 800m on moving targets!

http://www.battlefront.com/cgi-bin/bbs/ ... 029#000006

A good thread

Ok, I'll take a look through these tonight. Based on my first look though, I found this interesting:

Using the German figures for doubled random dispersion and assuming an average range estimate error of 25% with a bell shaped error distribution (typical results for average crew, based on British and American firing trials), the following first round hit percentages were computed against a stationary 2m high by 2.5m wide target:

FIRST ROUND HIT %

RANGE...50L60...75L48...75L70...88L56...88L71
500m...........81......75.....88.......79.....94
800m...........36......34.....51.......39.....61
1100m..........17......15.....28.......21.....34
1400m...........9.......7.....16.......12.....19

Muzzle velocities are 835 m/s for 50L60, 750 m/s for 75L48, 935 m/s for 75L70, 780 m/s for 88L56 and 1000 m/s for 88L71. All rounds APCBC except APC for 50L60

A 2m x 2.5m target size was used by the Germans as a reasonable model for the front view of a typical target tank, which simplified the calculations. Those dimensions simplify the complex variations in target width with height (T34 turret front is narrower than hull and has sloping sides, T34 hull width varies with height, etc.), and probably assume that ground rolls and folds blocked out some of the lower tank area.

The above stated estimates for first round hit percentage probably represent the high side of what would be expected from average troops in battle, since “nervous and/or fatigue” origin errors were not considered during the calculations. Under the stress of combat, people can forget intermediate steps and see things on the gun sight that are not there. Discussions on the AFV News forum site have brought out the possibility that unquantifiable human errors may account for a good share of the reported misses at “sure thing” ranges.

I don't know how much to trust these numbers, given that there is debate on them in the same threads and they represent effectively an addiitonal data point rather than a definitive answer for our purposes. Nevertheless, very very interesting. With that said, he comes up with a 75% hit rate for the L48 (we were looking at the L43). We're dealing with a smaller target in the T-70 and we end up with 50% after the first shot, so it looks like we're in the same ballpark, particularly since in our tables the accuracy sharply rises inside of 500m (<425m or so it's almost a guaranteed hit). Note also that we try to take into account the "human factors" mentioned above that tend to show up in battle. I'll have to review this info in more detail, but thanks for bringing it up.

Regards,

- Erik

I will try to find the actual thread but from memory, German gunners were to get a hit on a stationary target at 1200 meters (I believe its for 75mmL48 which is nearly the same as a L43) within 3 rounds. For a moving target at 800-1000 m it was also 3-4 rounds. Going from memeory but its probably very close to those numbers.

We then compared data from after action reports such as in Panzertruppen2. We then were able to closely correspond what happens on the battlefield with the gunner school criteria and also the statistical data that we were arguing over (dispersion, range estimation, etc).

We then could tie it all together. A very good model was then made by rexford using a computer program.

But basically it all boils down to 1. estimating the range, 2. initial shot and observation of shot, 3. correcting that shot, 4. iterating till you get a hit.

The Germans (IMO) had such an advantage at 800+ meters that I doubt they would want to fight at any range closer than that if they didn't have to. The ability to estimate range, observe shots and superior sights, optics, technique all added up to better gunnery than most of the allies.