Question about vehicle weapon hit probability

[LemuelG]

I'm not privy to the actual mechanics at play, but surely a hull-down tank is much harder to spot due to a far smaller profile. I'll take the first two shots over any other factor.

As a general rule, I try to avoid taking any fire at all - hits invite damage, once your hull-down spot is identified, reverse out and move to another - if your gonna sit around exposed then the best you can hope for in this game (against a human at least) is a few pin-point light mortar rounds coming your way, you certainly want to avoid a scenario in which you can be sniped with AP rounds. Even in a Panther.

[Magpie_Oz]

Not only is a hull down tank smaller but the apparent target is not as high so that makes getting the range spot on crucial to hitting it. A mis-estimation either way has you shot passing over or hitting the mound in front.

[Battlefront.com]

Coming in late, but here I am

Well, as others have said... the determination of where a shell hits is not done by probability like CMx1 was. In that game the factors, such as Experience, shell characteristics, gun characteristics, size of the enemy target, etc. all added up to a single chance of hitting. The more things were optimal, the more chance that the target would get hit. In any case, we could get a % number out of it to show people.

CMx2 does it far more simply. The gunner aims and the aim point is established based on a lot of variables, including some that have a random component. Leading, range estimation, crew factors, etc. all go into this part. The aim point might be way off target or perfectly placed. Whatever the factors come up with is what the system goes with when the shot is then fired. Once the round leaves the barrel it's pure ballistics to define the flight characteristics of the shell's path, including some randomness since no two shells have exactly the same characteristics. Obviously the randomness might have no practical influence based on the situation. Where the round strikes the round strikes. At no point in time is the system capable of predicting the shot's ultimate chance of success.

About hull down... there's a tradeoff with going hull down. Yes, it decreases your chance of being spotted and/or hit. This is always good. HOWEVER, if you put a tank with a weaker turret than hull armor in a hull down position you need to be aware that IF the enemy hits you it will most certainly be the turret that gets hit. Still, statistically speaking you should be better off than if you left your tank out in the open.

A post WW2 study of American tankers concluded that getting the first shot off was the most important aspect of tank combat. Being hull down, and aware of the enemy, probably resulted in a first shot opportunity. However, if you're 1 tank vs 5 tanks don't expect that advantage to last very long

Steve

[Bastables]

Well no it isn't it is the crux of the issue. The gun can only be mounted on single fulcrum and so has limits to its strength, as the other fellow have pointed out the trunnion is quite sensitive. The mantlets on nearly all WW2 tanks covered the whole front of the tank so the gun and mount would bear the full force of any hit to the turret front.

Granted the Stugs, particularly the ones with the pig's head mantlet, mitigated this, so too the Tiger II, but the mount is still vulnerable.

The best proof of this is to take a look at the M1, Leo2A6, Merkava and T80 , tiny mantlets

Or even the proposed small turret on German tanks which make the mantlet really small: ausf F turret. http://www.achtungpanzer.com/images/p5f_1.jpg

All were moving to minimising the mantlet as magpie indicates with the StuG and Tigger II mantlet. The Panther and Tiger 1 front turret= mantlet was seen as a development dead end even in WWII.

[jocke_p]

Coming in late, but here I am

Well, as others have said... the determination of where a shell hits is not done by probability like CMx1 was. In that game the factors, such as Experience, shell characteristics, gun characteristics, size of the enemy target, etc. all added up to a single chance of hitting. The more things were optimal, the more chance that the target would get hit. In any case, we could get a % number out of it to show people.

CMx2 does it far more simply. The gunner aims and the aim point is established based on a lot of variables, including some that have a random component. Leading, range estimation, crew factors, etc. all go into this part. The aim point might be way off target or perfectly placed. Whatever the factors come up with is what the system goes with when the shot is then fired. Once the round leaves the barrel it's pure ballistics to define the flight characteristics of the shell's path, including some randomness since no two shells have exactly the same characteristics. Obviously the randomness might have no practical influence based on the situation. Where the round strikes the round strikes. At no point in time is the system capable of predicting the shot's ultimate chance of success.

About hull down... there's a tradeoff with going hull down. Yes, it decreases your chance of being spotted and/or hit. This is always good. HOWEVER, if you put a tank with a weaker turret than hull armor in a hull down position you need to be aware that IF the enemy hits you it will most certainly be the turret that gets hit. Still, statistically speaking you should be better off than if you left your tank out in the open.

A post WW2 study of American tankers concluded that getting the first shot off was the most important aspect of tank combat. Being hull down, and aware of the enemy, probably resulted in a first shot opportunity. However, if you're 1 tank vs 5 tanks don't expect that advantage to last very long

Steve

Hi Steve!

Very interesting description, i have been very curious about the CMx2 targeting/aiming model.

Have you had time to consider my "original" question?

Is a 40% weapon hit chance against a hull down panther at 700 meters, from a regular 57mm AT gun crew, something you might expect and being "by design", or is it not intended to be that high?

BR

Joakim

[stikkypixie]

Hi Steve!

Very interesting description, i have been very curious about the CMx2 targeting/aiming model.

Have you had time to consider my "original" question?

Is a 40% weapon hit chance against a hull down panther at 700 meters, from a regular 57mm AT gun crew, something you might expect and being "by design", or is it not intended to be that high?

BR

Joakim

Sorry I have not been following the thread, but is that 40% first hit chance, based on your estimates? Or 40% of the all the shots?

[drexil]

Could it be that there are a number of weapons and weapon mounts on the front of the Panther? Not all the hits might be against the main gun.

I would also have thought that an AT round hit on a gun would be nasty. The tube would not withstand an impact meant to drive through solid plate. Or am I showing my ignorance?

I did up a testing scenraio for various US AT weapons vs Axis armor at different ranges and aspects if someone wants to do some testing.

[Magpie_Oz]

I would also have thought that an AT round hit on a gun would be nasty. The tube would not withstand an impact meant to drive through solid plate. Or am I showing my ignorance?

Hard to say what would happen if you hit the gun direct. I have seen photos of Arab T55's with penetrations to the barrel from Israeli 105 APFSDS rounds. I am not sure if WW2 ammo would be able to do it tho' Barrels are really strong, maybe as strong as armour plate and being cylindrical will more likely deflect rounds in most situations.

The main point is I think any hit from a reasonable size round be it HVAP or a HE on the gun itself or the mantlet is going to disrupt the gun and or its mount to a degree where it can fail.

[jocke_p]

Sorry I have not been following the thread, but is that 40% first hit chance, based on your estimates? Or 40% of the all the shots?

40% of shots fired at a hull down tank seems to hit the weapon, with the parameters i used. regular 57 mm AT gun firing from aprox 700 meter.

I wrote in reply 13

Hi again!

Ok i did a quick restest, 700 m open field, AT gun in tree line. All three panthers where in hull down and facing the gun.

The AT gun fired 22 shots:

3 misses

1 hit the "front turret"

9 hit the "weapon mount"

9 hit the weapon.

Result : 3 panthers with their guns disabled. That is roughly 41% gun hits of all shots fired at the hull down panthers. Does not that seem a bit high?

Edit! Also, let me explain how i got the test to run that long without the AT gun being knocked out. I manually "refaced" the panthers every couple of seconds, and i also buttoned them to lessen the chance of them spotting the AT gun. The Panthers did spot the gun after a couple of minutes but lost their contact sporadicly. I was also suprised it took 5-6 hits per panther before they started popping smoke.

Does anybody here know of good historic information sources where one might find information about hit locations on tanks, i suspect it will be hard to find. I would really like to know if my hunch is correct or if weapon hits actually where as common as this.

If NOT, then Battlefront might be persuaded to adjust their center mass aiming formula and increase the hit-width from center point a bit, so that the resulting hits are a little more historical. I am not saying it is unhistorical NOW, but IF facts would support it.

[stikkypixie]

40% of shots fired at a hull down tank seems to hit the weapon, with the parameters i used. regular 57 mm AT gun firing from aprox 700 meter.

I wrote in reply 13

Thanks, that wasn't completely clear to me. Have you take into consideration that once a crew find the right range to the target, the following shots will have very high probability of hitting? The initial shots will tend to miss because of inaccuracies in estimating the range, etc... but once the crew find the right "settings" to hit the target, the subsequent shots will tend to hit.

[Edit] Oops, I should learn to read . Did not see that you specified weapon. I assume that's the main gun?

[jocke_p]

Thanks, that wasn't completely clear to me. Have you take into consideration that once a crew find the right range to the target, the following shots will have very high probability of hitting? The initial shots will tend to miss because of inaccuracies in estimating the range, etc... but once the crew find the right "settings" to hit the target, the subsequent shots will tend to hit.

[Edit] Oops, I should learn to read . Did not see that you specified weapon. I assume that's the main gun?

yes the main gun was disabled on all 3 tanks within 22 shots fired by the AT gun. 9 shots of the 22 fired hit the weapon, 9 shot hit the weapon mount (i am guessing the mantlet on the panthers)

EDIT! just to clarify, the first weapon hit on each panther seemed to disable the gun, some weapon first hits also damaged other systems like optics. subsequent weapon hits worsened the damage to the other weapon related systems, again like optics. I redid the test several times and had roughly the same results. I did see a "first weapon hit" that did not disable the main gun (it was yellow so still damaged), but the next weapon hit to that panther promptly disable the gun. The point being that it did NOT take 9 weapon hits to disable their guns, it was more like 3-4 (roughly 1 per panther), the other 5-6 hits just made the damage worse. This would mean that it would take considerably LESS shots than 22 to "gun disable" all three panthers. I just let the AT gun fire more shots to get the ratio on weapon hits per shots fired at a hull down tank.

[MengJiao]

Nope (well, as far as I know), and I don't think that redwolf was claiming that it does. The point is that CMx2 may well do away with a "hit probability" in the sense that it does some complex calcualtions, comes up with a probability, and then generates a random number to see if it hit or miss, but what it does do is functionally the same. The code for the gunner might decide on an aim point, assign a random error in how well the gunner can acquire that exact aim point (either taking such factors as redwolf listed into account explicitly or by fudging it with a 'design for effect' plausible spread of errors, and then maybe add in some random spread to the shots from the actual (rather than intended) barrel position to account for other randomness (amount of propellant in the round, wind, wear and heating in the barrel, whatever) which assigns a second 'design for effect' spread of plausible errors. Or the randomness in aim error and the randomness in shot spread are rolled in to one uncertainty.

At any rate it doesn't matter much; the net result is that you pick a random number (or two, which is mathematically equivalent) and that ultimately determines whether you get a hit or not. So while there isn't an explicit "hit probability", there is still an implicit one, albeit in a form that you can't easily say which ranges of random numbers will result in a hit, or what the probability is.

It seems the CM1 probabilities are inherently frequentist and the CMBN probabilities are pretty Bayesian in that if you hit the gun once, you are a lot more likely to hit it again (because the hit model is a specific prior). So they aren't mathematically equivalent since the CMBN retains (it would seem) a Bayesian prior in its model.

[WineCape]

Hi Steve!

Have you had time to consider my "original" question? Is a 40% weapon hit chance against a hull down panther at 700 meters, from a regular 57mm AT gun crew, something you might expect and being "by design", or is it not intended to be that high?

Joakim

I repeat. Do a 'few' more test samples on the AT-gun crew hitting that enemy tank's gun before you can deduct there's NO outlier statistical result at work here wrt the turret aiming point of the AT gun. You cannot make any conclusion(s) from your results by doing only a couple of tests, unless I have missed your sample size. Maybe there is a problem in that gun% hit is too high given total to-hit shots on a hull-down tank's turret. If the protruding gun encompasses, say for example 20% of total turret, but hit% samples show, say 90% gun hits over a bigger sample, then obviously it's too high to be realistic, whether there are any documentary historical proof for such incidences or not. BFC will then, in all likelihood, investigate.

Create some firelanes [i have such a Beta Test multi-lane scenario if you need one; you just need to populate it with hull down positions and the appropriate units] and run some more tests to get a higher sample. I would have done it for you, but my patch test priorities are not the same as yours; time-wise and focus.

Regards.

[Battlefront.com]

Is a 40% weapon hit chance against a hull down panther at 700 meters, from a regular 57mm AT gun crew, something you might expect and being "by design", or is it not intended to be that high?

It sounds about right. The AT Gun and Panther are both stationary and the range fairly short. Therefore the chances of the AT Gun hitting the Panther within 3 shots is excellent. With 2 shots is very good, within 1 shot reasonably good.

When it hits, what does it have a chance of damaging? Look at my previous post about hull down forcing hits to be to the turret, which is generally weaker than the lower hull (at least the front).

The problem for the Panther is that pretty much the only thing it's given the AT Gun a chance to hit is its main gun or an attached system. 40% chance of somehow hitting the weapon system is, therefore, logically sound. If the mantlet was considered part of the weapon system (it isn't, AFAIK) then it would be near 100%.

OK, so now I expect someone to say something about the 57mm AT Gun not being able to take on 3 Panthers like that. I would agree there. Most likely situation in a real battle is maybe 1x Panther damaged, 1x AT Gun scattered around the battlefield in little pieces. 22 rounds fired at 3 Panthers in a real game? THAT would likely be a problem worth looking into

Steve