Panther turret weak point

[Ari Maenpaa]

Vanir,

Here is the thread about Hetzer’s armor: http://www.battlefront.com/discuss/Forum1/HTML/007180.html

Charles’ explanation is on page 2.

I made some additional testing and this time I let the tanks shoot

My criticism about Panther’s turret’s frontal armor was too hasty. I based my point just on theory but not on practice, so...

There already seems to be some modifier for front turret hits because even thought I saw occassional Front Turret Penetrations (not via weak points) beyond 500m they were by no means sure thing to happen even at 200m range. This seems to be pretty historical to me. Still I have to say that the Weak Spot Penetrations seemed to be VERY regular. Gotta be because of the shot trap.

And then something disturbing: Hits on Panther’s frontal lower hull ALWAYS resulted as penetrations. Even at 1200m range. This seems to be a major bug.

Basing on Charles’ explanation, Panther’s frontal lower hull’s effective armor is 0,85 * 60mm which is at 55 degrees = 51mm@55^. Sherman76’s data in CM says that US76mm penetrates 51mm@60^ at 500m with standard APs. So I would expect the lower hull to be penetrated up to 600m, but at 1200m?? NO change.

Maybe there is some historical explanation for this, so enlighten me, but if not then this is one more bug to squash. Until that it is better to keep those Panthers hull down.

I didn’t test with other tanks so I can’t say if this problem occurs only with Panthers or is it a bigger anomaly with some shared algorithm.

Ari

[Ari Maenpaa]

After additional testing I have to ask:

Is it OK that US76mm with standard AP-shot almost always penetrates Panther's frontal LOWER HULL armor at ranges beyond 1500m? And these are NOT weak point penetrations.

Same goes for Hetzer. Jagdpanther which has essentially the same lower hull armor than Panther, is somewhat more resilient to lower hull penetrations. Even that can be easily penetrated beyond 1000m.

To my thinking a typical lower hull armor on these vehicles makes such an angle for incoming shot (all tests done with Sherman76s face to face with targets on flat ground) that it is almost impossible get penetration against it. Ofcourse I can be wrong.

Is this a bug?

An expert's opinion would be appreciated. Thank you.

Ari

[:USERNAME:]

There was a similar discussion of this when panzer elite first came out. In that game the same thing was happening.

What isnt modeled is the trajectory of the shell ADDING to the downward sloping armor. In effect it is a small target "seen" by the firer.

Since the germans actually decreased the thickness from 60 to 50mm, there must have been some reason for doing so.

[Vanir]

Thanks for the link Ari. Very interesting.

I did a little test on my own and can confirm that the 76 will indeed penetrate the Panther's lower hull at 1200 meters. I would need one of our armor experts to say for sure if this is correct or not, but on the surface is seems a bit suspicious.

About the armor qualily thing... I am a bit confused. Charles says quite clearly that 110mm of armor at 85% should be equal to 93.5mm of 100% armor. Yet, if this were true the 76 would be able to penetrate the Panther's turret at ranges in excess of 1000m. But it can't. Not without a weak point/shot trap hit. So as far as I can tell either Charles misspoke or the code isn't working quite right. Additional input would be appreciated.

------------------

You mean my Java coded Real Time Bar Fight Simulator Madmatt Mission: Beyond BiteMe ISN'T going to be published?!?

Madmatt

[Dschugaschwili]

Charles' post regarding armor quality is rather old. So things might have changed since then. I would appreciate an official statement from BTS regarding this topic too.

Another thing about the Panther's lower hull: is this the part of this tank's front that's sloped "backwards"? If so, is the sign of the slope used for the internal calculations? Because this would mean that incoming shells that have arced down during flight would strike this part of the armor at a greater angle, thus reducing penetration capability. If the sign isn't used for the calculations, this could explain the long distance lower hull penetrations.

Dschugaschwili

[Tiger]

I posted a quote sometime back about US army tests in France in August '44 using HVAP (tungsten ammo) vs Panthers front glacis plate. They found that at ranges greater than 300 yards even this ammo could not penetrate the Panther's front glacis plate.

-john

[PzKpfw 1]

<BLOCKQUOTE>quote:</font><HR>Originally posted by Tiger:

I posted a quote sometime back about US army tests in France in August '44 using HVAP (tungsten ammo) vs Panthers front glacis plate. They found that at ranges greater than 300 yards even this ammo could not penetrate the Panther's front glacis plate.

-john <HR></BLOCKQUOTE>

Their were 2 Live Fire tests conducted by the US 1st Army the 1st was on July 12 1944. The 2nd set of tests was conducted August 19 - 21 1944.

Regards, John Waters

------------------

"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.

[This message has been edited by PzKpfw 1 (edited 11-27-2000).]

[PzKpfw 1]

<BLOCKQUOTE>quote:</font><HR>Originally posted by Dschugaschwili:

Another thing about the Panther's lower hull: is this the part of this tank's front that's sloped "backwards"? If so, is the sign of the slope used for the internal calculations? <HR></BLOCKQUOTE>

I am curious on this as well as the front lower hull would not be a 'regular' exposed target, due to its location, unless one was trying to skip a round into the belly armor or cresting a hill etc, yet I have seen hull down penetrations their in CM at ranges over 1000m.

Regards, John Waters

------------------

"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.

[This message has been edited by PzKpfw 1 (edited 11-27-2000).]

[Vanir]

<BLOCKQUOTE>quote:</font><HR>Originally posted by PzKpfw 1:

yet I have seen hull down penetrations their in CM at ranges over 1000m.

<HR></BLOCKQUOTE>

??? It should not be possible for a hull down tank to be even struck in the lower hull at any range.

------------------

You mean my Java coded Real Time Bar Fight Simulator Madmatt Mission: Beyond BiteMe ISN'T going to be published?!?

Madmatt

[jgdpzr]

I seem to recall that a preferred tactic of US tankers when facing the Panther head-on, especially when the German tank was on pavement or a hard surface, was to "bounce" a shot in front of the tank in hopes of getting it to skip up and penetrate the thinner plate of the lower hull.

I doubt this has anything to do with this situation, but I am curious if this has been considered at all.

[Guest Big Time Software]

CM models the early Panthers' shot trap and displays it as a "weak point" when penetrated. But it says "turret" rather than "upper deck", even though what's really happening is the shell bounces downward off the lower mantlet and then penetrates the thin upper deck armor.

All tanks have 'weak points' (even a King Tiger) that affect about 1% of hits. This value is not affected by armor quality. The shot trap affects a considerably larger number of hits (from the front). The underside of the Panther mantlet (i.e. shot trap) is a large enough area that hits there are infrequent but not rare.

As for rounded mantlets, CM does model this for certain vehicles, like the Panther and the StuG with the 'saukopf'. Basically it randomizes where the shell hits and so each shell can strike a different armor slope.

An armor quality rating of 85% means that 100mm of armor is treated as if it's 85mm thick.

Vanir said:

<BLOCKQUOTE>quote:</font><HR>About the armor qualily thing... I am a bit confused. Charles says quite clearly that 110mm of armor at 85% should be equal to 93.5mm of 100% armor. Yet, if this were true the 76 would be able to penetrate the Panther's turret at ranges in excess of 1000m. But it can't. Not without a weak point/shot trap hit. So as far as I can tell either Charles misspoke or the code isn't working quite right. Additional input would be appreciated.<HR></BLOCKQUOTE>

The answer is that the 76mm can penetrate the Panther turret beyond 1000m - but only if it's really lucky. First, it has to be a near dead-on perpendicular shot with little or no side angle. Second, it has to avoid hitting the upper curved surface of the mantlet, which would send the shell ricocheting skyward (this effect is not shown simply by the armor thickness rating - maybe we will add some sort of marker for this). Even with these in place, the 76mm still needs luck because the penetration is right on the borderline and there is a degree of randomness for all armor-piercing in CM, which can easily cause the 76 to fail in this case. So if you test it enough, you'll see the occasional 76mm penetrate a Panther turret (without weak point) beyond 1000m. It just doesn't happen often enough that I'd want to be that Sherman crew when the Panther starts shooting back.

About CM's displayed kill probabilities (e.g. "low", "OK", etc.): these are measured based on the exact positioning of the vehicles at the time you trace the LOS or targeting line. Once the action starts, the target vehicle may move or rotate, and completely change the equation. So you should use this information as a guideline only.

Lewis is right that CM doesn't model shell's additional downward trajectory. The reason we left it out is that a 76mm at 1000m would have a downward angle of roughly only half a degree. Closer-range shots are even less. Half a degree is unlikely to change results much, but we may add this in the future anyway.

Ari said:

<BLOCKQUOTE>quote:</font><HR> And then something disturbing: Hits on Panther’s frontal lower hull ALWAYS resulted as penetrations. Even at 1200m range. This seems to be a major bug.

Basing on Charles’ explanation, Panther’s frontal lower hull’s effective armor is 0,85 * 60mm which is at 55 degrees = 51mm@55^. Sherman76’s data in CM says that US76mm penetrates 51mm@60^ at 500m with standard APs. So I would expect the lower hull to be penetrated up to 600m, but at 1200m?? NO change. <HR></BLOCKQUOTE>

As you say, Panther lower hull armor is 60mm (x0.85 for quality = 51mm) at 55deg slope. CM's display shows the 0, 30, and 60 degree penetrations for weapons, but here's the 55-degree data for the U.S. 76mm:

76mm vs. 55 degrees slope

100m = 59mm

500m = 55mm

1000 = 51mm

2000 = 43mm

So at about 1000m, even directly perpendicular (i.e. no side angle) 76mm hits against the Panther's lower hull should be about a 50/50 chance of penetrating. Penetrations should be possible (though less than 50% likely, scaling down to 0%) out to roughly 1300m. If the Panther is rotated away from the perpendicular, introducing a side angle, these ranges drop considerably.

Charles

[Paul Lakowski]

<BLOCKQUOTE>quote:</font><HR>Originally posted by BTS:

Panthers armor is rated at 85%<HR></BLOCKQUOTE>

Why?

[This message has been edited by Paul Lakowski (edited 11-27-2000).]

[Ari Maenpaa]

Charles,

thanks for thorough explanation. It surely helped to correct couple of misconceptions I had about CM's armor modelling.

So the lower hull armor is the real "weak spot" on Panther's frontal skin. It's there where the millimeters really matter.

Theoretically a Panther made of 100% armor would very likely to be able to bear US76mm's AP-round on frontal lower hull armor even at point blank range.

I suppose that the difference I seemed to have between the tolerances of Panther's and Jagdpanther's lh. armors was most likely a statistical error (?).

Still I wonder the same thing that John already said (at least I think he meant this): Is there too many lower hull hits? Or is it always considered to be a hull down position when the lower hull is out of sight?

There is much talk in Jentz's Panther book how the crews criticized the thin side armors, but no such critic about front lower hull armor.

Also in the Panther II's design the Germans boosted the armor of older Panther's gun mantlet, turret front and glacis plate, but they DIDN'T touch the front lower hull armor. Wouldn't they have boosted it if it had been the cause for numerous Panther losses?

Basic open ground in CM is abstracted and considered to give some protection to soldiers moving across it. Wouldn't the undergrowth and such things similarly cover the lower hull armor of most tanks? Ofcourse this is model dependent for different tanks, but as you said, 76mm's shot doesn't have much downgrade angle so it would have to go through all the undergrowth to hit the Panther's lower hull armor.

I hope not to sound like suffering from an ubergermantank-fever

Ari

[Ari Maenpaa]

<BLOCKQUOTE>quote:</font><HR>Originally posted by Paul Lakowski:

Why?

<HR></BLOCKQUOTE>

Many Panthers (all of them?) were supposedly manufactured from deficient metal alloys, because Germany suffered shortages of numerous raw materials during the later war years. So that is abstracted in CM by giving all Panther-models only 85% effective armor when compared to the historical values.

Although I can't find a word about this from Jentz's Panther book, it is based on some metallurgical tests carried out by the Brits during the war.

Ari

[Guest Big Time Software]

Paul, vehicles that had documented armor quality problems have a reduction in thickness to simulate lower than spec defensive abilities. Most of the Shermans have such reductions as well. 85% is a number that Charles felt was conservative yet still likely to simulate the documented weaknesses vs. other vehicles' armor.

Ari,

<BLOCKQUOTE>quote:</font><HR>Still I wonder the same thing that John already said (at least I think he meant this): Is there too many lower hull hits? Or is it always considered to be a hull down position when the lower hull is out of sight?<HR></BLOCKQUOTE>

The chance of hitting a particular spot of a vehicle depends on the rough percentage of the profile that part occupies. If the lower hull is 20% of the total vertical target, then there is a 20% chance the shot will hit there. Or at least that is how I understand the way it works

A hull down vehicle can not be hit in the lower hull (or even upper hull?). At least by the weapon that it is hull down to.

<BLOCKQUOTE>quote:</font><HR>There is much talk in Jentz's Panther book how the crews criticized the thin side armors, but no such critic about front lower hull armor.<HR></BLOCKQUOTE>

This is not surprising. The frontal armor of the Panther was fantastic. But NO armor on ANY vehicle was perfect in all conditions vs. all guns. So it would be silly to complain about something that was overall very good. The side armor of the Panther was not, however, all that great.

To further illustrate this... I don't think I have ever seen any complaints about the thickness of a Jagdtiger's armor. However, I have a photo here of two penetrating hits in its side (through the roadwheels). No complaints does not mean perfection.

<BLOCKQUOTE>quote:</font><HR>Also in the Panther II's design the Germans boosted the armor of older Panther's gun mantlet, turret front and glacis plate, but they DIDN'T touch the front lower hull armor.<HR></BLOCKQUOTE>

No surprise there. It is a large surface and adding a meaningfull amount of thickness would have greatly increased the forward weight of the vehicle. Since the existing armor was generally very good, the designers instead placed emphasis on improving other areas. The turret is also towards the vehicle's center which means additional weight would be easier to compensate for.

<BLOCKQUOTE>quote:</font><HR>Wouldn't they have boosted it if it had been the cause for numerous Panther losses? <HR></BLOCKQUOTE>

"Numerous" based on what? In a perfect world, sure, the designers would have boosted the armor even if there was a small percent chance of getting KO'd. But there are practical reasons why things were the way they were. I'm sure that any Panther driver would love to have had 100mm of armor for their lower front hull, but since the vehicle could not take that sort of strain there is no point thinking about it.

Overall the Panther's frontal armor is fantastic. It is not so great that it can deflect all shots from all guns in all situations, but no tank can do that.

Steve

[PzKpfw 1]

I'm confused on the lower hull issue as if you look at a Panther the front is :

> <--------

The arrow would be an incoming round at the seam of the glacis. US tankers reportedly generaly aimed for the glacis as it was center mass. The front lower hull armor represents 20%? of the siliuette it seems rather high? as, if you look head on you see glacis & ground, its not exposed. I can see the FLHA exposed cresting a ridge etc but dead on I don't see a great % to even hit the FLHA.

All I know was the Panther was "hull down" the Sherman fired head on and killed it with an FLHA penetration. I have also killed a Tiger II with an front lower hull penetration with a 76mm Sherman at 1400m.

Regards, John Waters

------------------

"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.

[This message has been edited by PzKpfw 1 (edited 11-27-2000).]

[Guest Big Time Software]

John, the "20%" I mentioned was a made up number. I have no idea what the real value is

If you saw a lower hull penetration of a vehicle that was hull down to the unit that scored the hit, that is a bug. There is some sort of hull down bug in 1.05 so perhaps that explains what you saw.

As you say, a gunner (at least in average circumstances) aims at the center mass of the target. However, why does he do that? Because the degree of accuracy is not good enough (in most circumstances) to hit with exact precision. So you aim for the center expecting the round to hit somewhere around it. If you aimed for the lower hull you would stand a good chance of hitting the ground. But if you aimed for the lower lip of the turret you would instead have hit the lower hull. Range, gun, crew experience, and other important factors obviously play into this.

Steve

[This message has been edited by Big Time Software (edited 11-27-2000).]

[PzKpfw 1]

Agreed Steve I'm just confused on how the FLHA was being exposed.

Agreed, CQ etc, would play an big part just relating what I read on common aim points for US gunners.

76mm APCBC could defeat the Panthers front turret armor out to 700yrds if the round impacted on the thin horizontal strip of the vertical part of the gun mantlet, or on the almost vertical turret front to the sides the small flat turret front below & to the sides of the mantlet. 17Lb APCBC in British LF tests did defeat the Panther's mantlet at 600yrds. I have never heard 76mm APCBC could defeat the TF at over 1000yrds but then again all the LF tests were conducted at 200 & 300yrds.

The whole problem found in the tests was actualy getting the round in w/o hitting the mantlet, WW2 tank sights in general were not fine eneough to aim for the known weak spots even at 300yrds, so they fired center mass much like we do with rifles.

Regards, John Waters

------------------

"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.

[This message has been edited by PzKpfw 1 (edited 11-27-2000).]

[Guest Big Time Software]

Paul asked why we rate the Panther at 85%. The short answer is, "Ask Robert Livingston". He's the one that clued me in to the fact that the Panther's armor suffered from alloy shortages and was often quite brittle and far weaker than expected. Proof of this is demonstrated by combat reports and photos of shell holes in Panther wrecks that should not have happened when one looks just at the numbers. In other words, there are examples of (for instance) a U.S. 76mm shell penetrating a Panther glacis when the numbers say it just shouldn't have been able to do so. Livingston told me that he's found examples of Panther armor as weak as 75% quality, but since that appeared to be the low end of the spectrum, it seemed that 85% was a better value to go with.

Ari said:

<BLOCKQUOTE>quote:</font><HR>Theoretically a Panther made of 100% armor would very likely to be able to bear US76mm's AP-round on frontal lower hull armor even at point blank range.<HR></BLOCKQUOTE>

Right. I would think that this sort of calculation was in the minds of the Panther engineers. And had it not been for the alloy shortages (which appeared, I think, after the Panther was already designed and in production) the Panther's lower hull would have been adequately thick to repel all "medium" threats. And since the Panther is a medium tank, this makes sense.

<BLOCKQUOTE>quote:</font><HR>till I wonder the same thing that John already said (at least I think he meant this): Is there too many lower hull hits? Or is it always considered to be a hull down position when the lower hull is out of sight?

There is much talk in Jentz's Panther book how the crews criticized the thin side armors, but no such critic about front lower hull armor.

Also in the Panther II's design the Germans boosted the armor of older Panther's gun mantlet, turret front and glacis plate, but they DIDN'T touch the front lower hull armor. Wouldn't they have boosted it if it had been the cause for numerous Panther losses? <HR></BLOCKQUOTE>

Didn't the Panther II begin its design in 1943? If so, that's well before the regular Panther would have encountered any 76mm-armed Shermans, which is the weapon that I think we're discussing here as the "threat" to the Panther's lower hull. So by the time they had any feedback on this issue, the Panther II was already well under way in design (or perhaps even canceled by mid-late 1944?). Plus keep in mind that the Panther is a medium tank, so there is a limit to how much armor can be added without sacrificing needed mobility (and the Panther II was already adding armor to the glacis and turret as well as the vehicle sides, I think).

In many battles I'm sure the Panther would be hull-down as well, negating the lower-hull "weakness" (if that's the right word) altogether. And the side armor on the Panther is so thin (relatively speaking) that if I were a crewman in a Panther, I think I'd complain about the side armor before anything else too.

Also note that when the Americans up-armored later models of the Sherman (regular models, not just the Jumbo) they massively reinforced the lower hull - doubling it's thickness in parts. The lower hull was a decided weakness of the earlier Shermans. So hits there are not so uncommon after all, I would think.

Whether or not CM has too many hull hits is open to debate. We've set it at roughly 15% of hits for a typical tank. But it's hard for us to say if that's exactly right.

John mentioned a hull-down Panther getting hit in the lower hull. There was a bug in hull-down status in v1.05 which we have fixed for the upcoming v1.1.

Charles

[:USERNAME:]

The Germans REDUCED the lower hull armor if I recall from 60mm to 50mm. This was done to the later models. So they felt that this area was not vulnerable it would seem.

I wonder if Charles can explain how he figured out the angle for the 76mm example he gave? Is it a tungsten round?

Are hit area calculations on a percentage distribution? That is, once you get a hit on a tank, is the exact area like the lower hull a percentage basis on its square area?

I think that a tank weapon like a high mounted sherman gun would be firing down at this small target area. Is BTS aware that a shell that is fired at a certain super elevation degree falls at a steeper angle? So if you fire a shell at lets say 5 degrees it will fall onto the target steeper than 5 degrees?

Lewis

[Paul Lakowski]

I think 85% is far to high for any tank as an across the board figure.

A couple of years ago Maraging steel [ very strong] and Tool steel [ high carbon] were tested against Rc -27 plate with AP shot at ~ 800m/s and both were found to offer 90% of the resistance of the RHA standard.

David Honner puts the value for 'flawed plate' at only 90% which is in line with the above mentioned tests.Now if localized 'weak areas' were the yard stick this might make more sence...the reason Hetzer would have 85% would be that most of its armor was mild steel [ 199 BHN], which is known to offer only 66% of RHA @ 150BHN and 80% of RHA @ 180BHN.

Panthers armor was 260-285 BHN and should not suffer as much of a reduction.The Free edge effect guarantees that the most of the front turret and some of the glacis should offer less resistance.

I have resently determined that the Free edge effect on WW-II APC shot was far less than modern APFSDS bring it down to 1-3 projectile diameters from the 'free edge'.[ APFSDS its upto 30 projectile diameters]

That should mean within 15-20cm of the Panthers MG ports on the mantle and glacis as well as the optical ports on both should be weakened offering 70-90% [the closer to the edge, the lower the value].

In addtion the edge of the mantle constitues a 'free edge' to the mantle plate and the front turret plate.

[PzKpfw 1]

<BLOCKQUOTE>quote:</font><HR>Originally posted by Big Time Software:

Paul asked why we rate the Panther at 85%. The short answer is, "Ask Robert Livingston". He's the one that clued me in to the fact that the Panther's armor suffered from alloy shortages and was often quite brittle and far weaker than expected.

Charles<HR></BLOCKQUOTE>

Charles is correct to an extent as the alloy shortages of nickel & molybdenum affected later versions of the Panther Ie, the later Ausf A & G runs. But the main problem concerning the Panther armor was again from Robert, the quenching process which he believed reduced the Panther's glacis equivelent protection by 10 - 20% IIRC.

Concerning armor quality I would also point out, that Robert has gone into that the British Churchill's armor for example, which effect's CM; (in that its modeledas an AFV in CM) as most Churchills were built prior to the Mid late 1944 British armor industry overhauls. Has been generaly overated (not meaning in CM terms in general terms its protection was overated) based on its armor thickness, as it's armor in reality like all british tank armor, prior to mid 44 was of poor material quality. Especialy in any thickness over 57mm Ie, Robert posted on Tankers IIRC msny moons ago, that 152mm of British plate only gave the actual equivelent protection of 137mm. In CM the Churchills for example are all rated 95% AQ

The poor quality armor in British tanks due to poor steel construction their Steel industry was small & spread far & wide, Robert once refered to the British armor process prior to mid late 44 IIRC; as 'seat-of-pants metallurgy'

Regards, John Waters

[This message has been edited by PzKpfw 1 (edited 11-28-2000).]

[Bastables]

<BLOCKQUOTE>quote:</font><HR>Originally posted by Big Time Software:

As for rounded mantlets, CM does model this for certain vehicles, like the Panther and the StuG with the 'saukopf'. Basically it randomizes where the shell hits and so each shell can strike a different armor slope.

Charles<HR></BLOCKQUOTE>

Dammit you chaps are good.

[This message has been edited by Bastables (edited 11-28-2000).]

[Ari Maenpaa]

<BLOCKQUOTE>quote:</font><HR>Originally posted by Bastables:

Dammit you chaps are good.

<HR></BLOCKQUOTE>

Gotta admit that. It just feels so good to know how many little things this game takes in consideration even in the most intense moment of heated battle. Absolute pleasure

Ari

[Vanir]

One of the things I'm most happy about now that TCP/IP is done is having Charles back on the forum. Welcome home

------------------

You mean my Java coded Real Time Bar Fight Simulator Madmatt Mission: Beyond BiteMe ISN'T going to be published?!?

Madmatt

[This message has been edited by Vanir (edited 11-28-2000).]