Is artillery too powerful against tanks?

[:USERNAME:]

Great timing Henri, I did mention that study and I put it in its proper light.

Arty also throws up big clods of mud and smoke and flash. This gets all over periscopes , vision blocks and generally degrades a tanks performance.

Lewis

[Jeff Duquette]

Henri:

It’s not particularly incredible. I mentioned this study in my very first posting on this thread (see page 1 of this thread). The critical section of this report can be viewed at:

http://www.geocities.com/jeffduquette/tank_casualties.html

I have also elaborated on similar statistical studies in this thread conducted by Richard C. Anderson for the Depuy Institute…see my post on page 4. Statistics on Soviet vehicles, 1st Tank Army, Kursk showed slightly over 14 percent tank casualties attributable to HE. With respect to my previous mention of the British study, 21st Army Group, look closely at the dates covered…should reveal something to you regarding the low percentages of Commonwealth tanks suffering damage from HE.

I don’t know about a 25% ratio in CM, but from what I have seen the CM stats certainly seem somewhat on the high side relative to real world numbers.

[Bobbaro]

Only a general impression, but recalling all the reading on artillery falling on armor in accounts of combat, my impression is that the usual effect was that the armor would withdraw. That suggests to me that the tankers had some very good reasons to do that. Whether they are or are not impervious to being knocked out seems besides the point, if that is an accurate impression of typical tanker behavior.

For CM purposes, it would be appropriate to get that response simular to backaing away from a frontal threat.

It also seems that we may be developing a fair consensus that we get a tad too many knockouts due to direct hits than we should. I gather that a shell landing on the engine area is going to likely cause some serious disruption, and a large HE on the remaining top armor could split a tank open at least sometimes. A large caliber hit anywhere can casue some trouble if only to the crew's outlook moral and literal.

So, I now have a picture of a barrage landing near armor, 1. they get the hell out of the impact zone as quickly as possible, 2. a few get disrupting effects, (muddy periscopes, broken antenna, tracks start a worrysome squeeling, things that make the vehicle head for the rear for repairs.) 3. a smaller few get serious but non killing damage which may or may not immobilize the unit, 4, a rare few find that shell that lands on the engine compartment or open hatch. The chance numbers involved, I will not speculate.

As far as getting of out the impact zone, one can advance out it as well as withdraw, but I bet, that withdrawing would be favored. I know that I would like to check out my tank under cover, cleaning off such junk that had been blown on periscopes and making sure that antenna was not hanging by a thread before I risked becoming totally blind with smallarms and shrapnel advising against an unbuttoned view.

Could a vehicle cleanup, checkout be handled like a jam, but require no LOS of enemy and no nearby indirect fire?

I just got through close assaulting a piece of armor using two squads advancing and one in a upper floor. First immobilization, then knockout. Nice. Oh, and one other succombed to a combo of 105 and 81mm indirect fire. Again, first immobilization, then this time abandonment. I was totally surprised by the overall result, a total victory. I had lost 15 vehicles. What I did not appreciate and could not know was that the AI had had its infantry decimated and redecimated as compared to mine suffering relatively little. His loss to indirect fire was 6 percent, a not unbeliveable result in this case.

[Henri]

Jeff,

My apologies, I guess I read the long thread a bit too fast and missed your reference to the study.

Username,

My apologies toyou too; since your message is the very ast one before mine, it is my impression that it was not visible to me when I wrote mine, since I had been on the site for some time and your message predates mine by about an hour.

Anyway, I'm glad to see that people here are aware of those studies. I wonder if BTS is going to do anything about it.

I would add that tanks are also much too susceptible from near misses by light artillery. I don't question that a 250 mm shell on the top of a tank could kill it and a near miss could disable it, but smaller caliber artillery should have much less effect. Unfortunately this is hard to quantify.

henri

[CrapGame]

I was playing a QB this morning, and the AI was pushing its squads of Tommies towards one of the VL's when I moved one of my StuGIII's out of its hiding place.

It blasted a few troops, then exploded from a "Top Hit, Weak Point". After scanning the map through multiple viewings of the film (at least 5 times), I have determined that the kill was done by a 2" mortar. There were no PIAT's, all troops were properly identified, the Brit Armor (1 firefly, 2 shermans) were already dead, and no troops were even close to near enough to assault the StuGIII.

I have no difficulty in believing that artillery of some size (say 75mm at least) could cause this death to an AFV to happen, but a 2" mortar? I figured the mortar would just give some big headaches to the crew of the StuG at worst, so I had it target the visible HQ units as a priority over the mortar. Serves me right, I suppose.

Just my $.02

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CrapGame

[ahauschild]

Guess you left the hatch open.

[Schugger]

Just a shot in the blue:

If you see so many tanks effected by artillery fire in the game, isn't it possible that some players tend to buy unusual heavy artillery assets for a battle which took part on a field roughly one square kilometer large?

[CrapGame]

ahaus,

Funny - you're probably right, the crew did seem to be a little too relaxed as they were mowing down those tommies. Oktoberfest is coming to an end soon, isn't it?

Schugger,

I had a thought about that, too, but the AI had purchased the forces for both sides. I think it wasted all the Brit's points on Air Support which didn't arrive. I did hear it circling around, though. It gave me a ton of artillery - a 75mm spotter, a 105mm spotter, a 75mm infantry gun and 2 81mm mortars. The end result was 110 casualties for the Brits, of which only around 20 were credited to my StuGIII and the 75mm AT gun. My 2 platoons of fallschirms didn't fire a shot before the Brits surrendered. Did seem like a lot of firepower for a 1000 pt qb.

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CrapGame

[Jeff Duquette]

Kinetic Energy: The kinetic energy model the majority of us are familiar with is basically laid out in a form similar to the following: The Kinetic Energy of an object is equal to half its mass multiplied by its velocity squared. Or:

K.E. = 1/2MV^2 (excuse my use of the "^" symbol for an exponential…no super script is available for UBB.)

Where M is the mass of the shell

and V^2 is the decent velocity of the shell at the instant the shell impacts.

At the instant of impact, kinetic energy begins to degrade through friction…i.e. in the case of an AP round; the shell expends its kinetic energy in piercing an armored plate of a tank. Pretty basic.

High Explosive Rounds The majority of common High Explosive rounds being employed during WWII were designed with an impact fuse. In other words the shell casing bursts into deadly little fragments and splinters upon impacting: the ground, or a wall or a roof, or the deck of a tank, etc.

In the case of a High Explosive round impacting the deck of a tank; At the very instance when any penetration of the HE round begins (i.e. penetration in the since of what we would expect to occur during the progress of an AP round through armored plate)...the HE shell casing bursts. The fuse in the shell does its business and the round explodes. Ideally the fragments are spread radially away from the point of impact. Funneling of fragmentation into the point of impact would defeat the effectiveness of High Explosive rounds.

Kinetic energy of an HE shell (and therefore the decent velocity of the shell) is lost or more properly radically redirected following the shell burst. In other words there is really no mass to apply the downward velocity to.

Back to our original kinetic energy model of ½ MV^2

As M approaches zero, KE also approaches zero.

This is loosely analogous to HEAT munitions or other shaped charges. Velocity of impact for a HEAT round has nothing to do with penetrating capability of the munition. Armor Penetration occurs as a result of a very focused explosion. The obvious problem with the HEAT analogy would be (as Fernado has already indicated) the blast from a high explosive round is very unfocused. It spreads out away from the impact point, with the intent of imparting kinetic energy to those deadly little fragments and splinters. But incase there is some confusion on this point, the kinetic energy present in fragmentation has nothing to do with the decent velocity of the HE round prior to burst. The energy imparted to fragmentation is done so via the energy of shell detonation. In addition much of the energy from the blast is dissipated in friction to the areas surrounding the blast. Be that: pushing huge masses of air molecules away from the blast point, shattering structures, or displacing soil and rock mass (and leaving large impact craters in the ground).

Even if we assume that tiny shell fragments and casing splinters are contributing to armor penetration...consider the following: The velocity of a pressure blast emanating away from TNT at detonation is occurring at over 6,000 meters per second. The muzzle velocity of an 88mmL56 firing (i.e. a Tigers I's main gun) firing Pzgr. 39 is about 773 meters per second. Now assuming absolutely no frictional loss of the Pzgr 39 as it speeds its way toward its intended victim, pushing aside countless O2 and other gas molecules effortlessly (i.e. ignoring air friction), we are still looking at the velocity squared term in our original Kinetic Energy equation of 60 fold between the Pzgr 39 and shall fragments propelled by a exploding HE round (6,000^2 relative to 773^2).

To further magnify the relative unimportance of HE shell impact velocity to armor penetration or tank damage, HE typically is traveling at considerably less velocity than an armored piercing round fired from an 88mm. But again, by design, a HE shell with a properly functioning detonator will break into thousands of pieces at the instant of impact.

So I would still contend that a HE shells impact velocity has "no significant" contribution to "penetration" or AFV damage.

[This message has been edited by Jeff Duquette (edited 10-02-2000).]

[gorilla]

I have always questioned the actual effectiveness of artillery in computer games. I have always felt that arty was not properly accounted for. Steele panthers/ close combat etc. Once you have seen artillery actually fired/impact, you don't quite understand how ANYTHING could stay intact in that particular impact area. Arty is nothing to play around with. I wish I could remember the exact numbers of certian statistics that I learned while I was in, but, I'll include some of these things anyway.

Historicaly speaking, arty has been THE major cause for battlefield casualties. I believe that the percentage was between 60%-80%? I also know that anyone that carried a radio/ looked like an FO, had a much lower expected time of existance on this planet, than almost any other military occupational specialty (MOS). Why? Cause Arty really really really sucks if you are on the recieving end. My expected living time (Arty radar) wasn't all that high either. (Getting rid of something that can see where your arty is, is perty important, cause having arty/ not having arty WILL make/break your situation)

Anyway, I want you all to take note, that I HAVEN'T played too much of this game, and I have only played the demo 3 times. (I did order it tho, so full version is on the way... )But in my honest opinion, it seems like the arty has been misrepresented (again.) But, not as bad as in other games. Maybe we should all get an idea of what we would like to see from this aspect of the game, and propose it to the fowlks at Big Time Software for an update/patch?

Ok, enough negative banter from arty from me. I would like to point out the things I have seen that I do like: For one, I like the actual arty spotting. It seems perty close to the truth (fire-adjust, fire-adjust, fire-adjust, fire for effect(FFE)) I also like the need for spotters. It takes some skill to call in an arty barage. I did some training with some FO's, and I can tell ya, it takes some getting used to.

[Jeff Duquette]

Yo Gorilla:

If your up for it, drop me an email when you get the full blown version. We can do some Play by Email Games. My Address:

jeffduquette@hotmail.com

[CavScout]

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

Just a shot in the blue:

If you see so many tanks effected by artillery fire in the game, isn't it possible that some players tend to buy unusual heavy artillery assets for a battle which took part on a field roughly one square kilometer large?<HR></BLOCKQUOTE>

Good points... how about they may be packing their tanks in to close. I know in the modern world we tend to keep around 200 to 250 meters between tanks to prevent arty kills.

Cav

[Jeff Duquette]

Cav Scout:

The impression I've gotten from various folk presently serving in armor branches of the army\marines regarding the effectiveness of indirect artillery fire vs armor are about as diverse as the opinions thrown out on this thread.

This is an interesting remark from a US ARMY Armor School memo: <BLOCKQUOTE>quote:</font><HR> "...the Armor School nonconcurred with the Artillery School regarding the suppresive effects of

artillery...the M-1 main battle tank cannot be destroyed by artillery..."<HR></BLOCKQUOTE>

With respect to Schugger's comments...the original discussion started regarding a "stock" CM scenario (Chamois I think...1st Polish Armor vs. 2nd Panzer). Polish artillery assets consist of a single battery of 25 pounders. I managed to kill a cluster of vehicles consiting of: a Panther, a MkIVh and Halftrack with the 25 pounder battery. Another poster describes the same scenario in which he lost a Panther to this battery of 25 pounders.

[This message has been edited by Jeff Duquette (edited 10-03-2000).]

[Jarmo]

<BLOCKQUOTE>quote:</font><HR>Originally posted by Jeff Duquette:

This is an interesting remark from a US ARMY Armor School memo<HR></BLOCKQUOTE>

Hmm, what's the thickness of abrams top armor? Does anyone know?

[gorilla]

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

Hmm, what's the thickness of abrams top armor? Does anyone know?<HR></BLOCKQUOTE>

When talking about modern armor, your no longer talking WWII steele. The differences in protective ability of similar thickness armor from WWII to modern day is vast indeed.

The two can't be compared. Yer also getting into the realm of composite armor. layers of different materials sandwiched together to provide much better protection. I read at: http://www.defencejournal.com/jul99/abrams.htm

that the armor is "similar to the Chobam armour developed by the UK Ministry of Defence. The M1A1 tank incorporates steel encased depleted uranium armour."... basicaly a steele sandwich with a depleted uranium core. As far as this thread is concerned, Modern day armor and WWII armor can't be compared. If yer just curious about the thickness of an M1's top armor... I don't know if you could find it. I couldn't. I wouldn't be surprised if it was still classified.

[Jeff Duquette]

<BLOCKQUOTE>quote:</font><HR>Hmm, what's the thickness of abrams top armor? Does anyone know?<HR></BLOCKQUOTE>

Jarmo…top thickness is beside the point To elaborate on the point being made; Even today a controversy exists between the ARMY Artillery School and Armor School as to the effectiveness of artillery against tanks.

Thickness and armor composite may be different than WWII, but tank killing artillery munitions are considerably different as well.

Hmmmm... M712 Copperhead, XM898 SADARM, M741A1 RAAM, M718A1 RAAM, FASCAM.

Gorilla: another nice web site.

[This message has been edited by Jeff Duquette (edited 10-03-2000).]

[CavScout]

<BLOCKQUOTE>quote:</font><HR>Originally posted by Jeff Duquette:

Cav Scout:

The impression I've gotten from various folk presently serving in armor branches of the army\marines regarding the effectiveness of indirect artillery fire vs armor are about as diverse as the opinions thrown out on this thread.

<HR></BLOCKQUOTE>

No doubt about that. Ask any DAT ^TM (Dumb Ass Tanker) and they will tell you that not even God could scratch their armor. They'll tell you how they can shot a fly of an enemy tank at 5,000 meters.

Of course, then you ahve a Table VIII and that talk is put in perspective...

Cav

[This message has been edited by CavScout (edited 10-04-2000).]

[Pacman]

For those interested, I destroyed a sherman using an 81mm artillery call on a TRP (well it was a lucky hit The tank exploded with a "top penetration, weak spot" message.

[Jarmo]

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

For those interested, I destroyed a sherman using an 81mm artillery/B]<HR></BLOCKQUOTE>

Hmmppffhh.. I destroyed a PzIV with a 2" mortar. A catastrophic explosion too.

[Pacman]

I must admit, that is impressive

[jlsimpson]

The answer is yes your point fernando has been proven . but the hysterical followers refuse to give way .

[Jeff Duquette]

Well after some controlled player made scenarios in which I wanted to see the effect of Indirect Artillery (FO’s and FOO’s) and mortar teams vs. tanks. I came up with the following:

The 81mm, 3in, 60mm, and 2inch mortars are very devastating against stationary MkIV’s. Basically pitted one or two teams of each mortar type against 2 MKIV’s. Performed several iterations of one mortar type vs. the MKIV’s. Placed the MkIV’s on ambush so they wouldn’t fire back. Tanks were buttoned-up and stationary (they had to just suck it up). I came to the conclusion that even light caliber mortars will take out MKIV’s on a regular basis, if the tanks sit still, and don’t fire back. I couldn’t tell you if there is a historical precedence for 2inch mortars taking out tanks…I certainly have never read about such a thing happening. My gut feeling is that this would have been a relatively rare occurrence in combat.

An odd side effect was that the light mortars will not “hold” their target. Moreover, they would fire one round and than lose there red target line for the remainder of the turn. I had to continually retarget the tanks between successive turns.

[chrisl]

For another datapoint (not controlled conditions) of CM arty vs CM tanks. I was playing allies in a recent scenario, and arty was a big part of my plan. I had four FOs:

2x 81 mm mortar (200 rounds each)

1x 105 mm arty (150 rounds)

1x 14 inch arty (10 rounds)

plus 6 on map 60 mm mortars split into two batteries with on map observers. (about 30 rounds each)

My results were:

a bunch of german halftracks killed, abandoned, destroyed, and immobilized. I don't think that's at all surprising, as they're thin walled and open topped.

1 StuH immobilized (I think by the 105) later killed by infantry

2 hetzers with gun damage

1 other hetzer immobilized (by the 14") later destroyed by a zook

1 panther gun damaged

1 panther TC kill (maybe done by infantry)

The arty didn't destroy a single tank, despite numerous barrages. I can't tell how many direct hits there were, but clearly enough to damage three guns. Even the 14" stuff didn't destroy the hetzer in the blast zone.

[Henri]

I don't think the problem is too many tanks being killed by artillery, I think the problem is too many tanks being immobilized or suffering gun hits from artillery.

Henri

[Ron]

Browsing usenet I came across a similar discussion and thought I would post some of it here.

<BLOCKQUOTE>quote:</font><HR>Paul Vebber wrote:

While we likely will never be able to answer the questions with certainty based on period data, we can make some inferences about it form that and other data avaoable. UK War Office reports document the following:

WO 291/399 Casualties to Churchill tanks in 25-pdr concentrations.

A trial conducted in 1943 tested proposed new tactics, whereby Churchills would advance though concentrations of friendly 25-pdr fire, by twice driving a squadron of Churchills through live artillery fire. It is concluded that the worst that can happen to a Churchill in these circumstances is immobilisation. The effect of a 25-pdr round exploding on a Churchill is described thus:

"There is no adverse effect on the crew from a 25 pdr direct hit. Fragments cannot penetrate the tank, and the blast is not at all uncomfortable."

WO 291/1186 The comparative performance of German anti-tank weapons during WWII. This report is dated 24 May 1950.

The percentage of tank losses, by cause, for different theatres is given as follows:

Theatre (tanks) Mines ATk guns Tanks SP guns Bazooka Other Total

NW Europe (1305) 22.1% 22.7% 14.5% 24.4% 14.2% 2.1% 100%

Italy (671) 30% 16% 12% 26% 9% 7% 100%

N Africa (1734) 19.5% 40.3% 38.2% nil nil 2% 100%

Mean values 22.3% 29.4% 25.3% 13.5% 6.1% 3% 100%

of which destroyed 20.3% 29% 24.4% 12.7% 5.4% - 91.8%

of which damaged 2% 0.8% 0.9% 0.8% 0.7% - 5.2%

Caution is advised over the "damaged" figures because of variability in reporting.

It is stated that tanks and SP guns should be considered together, as war diaries often show doubt over what exactly caused a tank loss.

Percentage personnel casualties, by type of tank:

Tank type Mines ATk guns Tanks SP guns Bazooka

Sherman 24.6% 41.4% 60.5% 54.3% 44.7%

Churchill 14.7% 45% 46.7% 30% 14.7%

Stuart 34.6% 29.8% 51.7% * *

Crusader * 38.5% 41.7%

Cromwell. Valentine, Matilda, Grant 17.4% 34.4% 28.6% * *

Mean values 21.8% 40% 46.4% 48.4% 38.6%

Of which killed 4.8% 18% 21.8% 20.4% 18%

Of which wounded 17% 22% 24.6% 28% 20.6%

An asterisk indicates a sample smaller than 30. These are included in the mean values.

The apparently greater effectiveness of mines in Italy is credited to the differing nature of the terrain, with more defiles than found in other theatres. It is estimated that about 2,000 German ATk mines were planted per tank casualty inflicted.

Of note here is that "ARTILLERY" or even HE is not even a category, leading one to the conclusion that it was not a sginificant cause of casualties.

WO 291/1321 The accuracy of predicted fire.

"It is estimated that broadly speaking an A.G.R.A. firing at 12,000 yds with all guns concentrated will deliver about 2/3rds of the shot not very far from uniformly into an area 200 yds by 200 yds, the remainder being scattered rather thinly beyond these limits." If one assumes say a 4x6 m "foot print" for a tank a roundin needing to land within 5m to have a chance to damage the target that menas a 14x16m vulnerable area - or 224 sqm area out of 40,000 or about a .5% or 1 in 200 chance of a nartillery round landing in the vulnerable area of a tank. If we need an actual strike, then the probability becomes 20/40,000 or 1 in 2000 rounds would actually strike a tank in the beaten zone.

Now the nature of artillery and tank combat mean that the noise and concussion from artillery will play havoc with both intra and inter-tank C2. THis effect of preventing effective comms in and near teh beaten zone is teh factor resonsible for many instances of artillery 'disrupting" tnak attacks. The occupants of teh tnaks being unable to communicate in teh midst of a heavy baaarrage. Thus one reads often of the "disruption" or "scattering" of armored attacks by artillery but rarely of vehicles being actually hit.

Now what we would today call "operational fires" the massing of Brigade and division sived arty units against armored spearheads did cause significant actual casualties, but these are tyopically not tactical "call for fire" situations CM deals with, but diisiona nd Corps commanders acting on recon about concentration of enemy force well before an actual attack.

So from the British War office data, aand a litle first order analysis, an actual hit on a tank by artillery is a VERY remote possibilty. The "effect" of a round acting adversely is less obsure, and teh general effects of disruption and C2 problems were endemic in even harrassing bararages.

Paul Vebber<HR></BLOCKQUOTE>

<BLOCKQUOTE>quote:</font><HR>John Waters wrote:

Here's data from the British report on the examination of captured tanks, and cause of loss where determined for each tank.

*June 6 - August 7 1944

110 tanks examined:

53 - AP shot

8 - Hollow charge

9 - Artillery, HE

1 - Mine

7 - Aircraft RP

3 - Aircraft cannon.

7 - Destroyed by crew

4 - Abandoned

18 - Uknown cause

August 8 - August 31 1944

223 Tanks examined:

24 - AP shot

1 - Hollow charge

4 - Artillery, HE

7 - Aircraft RP

1 - Aircraft Cannon

2 - Aircraft bomb

108 - Destroyed by crew

63 - Abandoned

13 - Uknown cause

December 17 1944 - January 16 1945

57 Tanks examined:

18 - AP Shot

3 - Artillery HE

1 - Aircraft bom

3 - Possibly by Aircraft

13 - Demolished

11 - Abandoned

8 - Uknown causes

*See: Jentz Thomas L Panzer Truppen Vol 2. p.189, 190, 202.

Regards, John Waters<HR></BLOCKQUOTE>

Ron