Is artillery too powerful against tanks?

[Schugger]

Perhaps it is not the kinetic energy of the shell that does the damage, but the shockwave of the explosion?

Do not the "Haftminen" ( magnetic mines?) work like this as they don't have any kinetic energy?

[Guest KwazyDog]

Something else I think should be taken into consideration is the fact that the rear hull of a tank often has many areas that would be thinner than the standard top armour figure given for the afv due to air vents, engine covers, etc.

[Fernando]

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

The inability of a Panther to resist the impact of a direct hit from a 25 pounder on its upper deck or the top of its turret is not, I’m sure, in question by anyone on this thread. <HR></BLOCKQUOTE>

I’m afraid I question it Please remember a 25 pounder isn’t a big caliber gun. Just 88 mm. If Russian 76.2 and 122 mm shells failed to penetrate Panther’s top armor in Kursk then I don’t see how the British 88 can in western Europe. IMHO a shell fired by field artillery hitting the top armor of a tank has MUCH less kynetic energy than HE shells fired by the same gun using direct fire so they can’t penetrate the top armor of most of the non open top vehicles. I’m pretty sure an external explosion can do a lot of damage (immobilization and/or gun damage in game terms) but it can’t penetrate the armor.

When a field gun fires a shell you can break its velocity vector in a vertical and a horizontal velocity vector. The verticall vector ALWAYS becomes 0 at the peak of the trajectory then the gravity increases it. The vertical vector of a shell felling from a height of 500 is less than 100 m/seg when it hits the ground, About 140 m/seg when it falls from 1000 meters and less than 200 m/seg from a height of 2000 meters. Please notize I disregard the air resistance. If you take it into account then the final velocity is even smaller. They are VERY LOW velocities. Mortar hits the ground and the top armor of a tank with an angle close to 0º. Their only vertical velocity is that produced by gravity and its horizontal velocity is VERY small too. A mortar shell falling from a height of 500 meters hits the top armor at about 100 m/seg so its kynetic energy is about 64 times smaller than that of an AP shell hitting that armor at 800 m/seg. If you take into account that those mortar shells aren’t designed to penetrate armor then their penetrating power is perhaps more than a hundred time smaller than that of the AP shell (or the armor is about a hundred times more effective stopping the mortar shell than stopping the AP shell). AFAIK field guns and howitzers hit targets at a larger angle than mortars. The vertical velocity is also dependent on the height attained by the shell (same values as mortar shells). I guess the horizontal velocity is greater than that of a mortar shell but it isn’t so great as that of an AP shell. Please, remember guns fire at targets some kilometers away (up to 15-20 Km) most of the time so the effect of air resistance over them is much greater than the effect felt by AP shells. The kynetic energy of a howitzer shell falling over Panther top armor from a height of about 1000 meters with a horizontal velocity of 200 m/seg is about 9-10 smaller than that of an AP shell hitting it at 800 m/seg. If the shells hit the armor at an angle close to 0º then its horizontal velocity is close to 0 and its kynetic energy is about 16 times smaller. If it hits the armor at greater angles then its kynetic energy is greater (but still about 9-10 times smaller) but then we must take into account that they hit that armor at an angle so the Panther effective top armor isn’t 16 mm but greater (20-25 mm?). Artillery shells aren’t designed to penetrate armor so I guess they are about 10-20 times less effective penetrating armor than AP shell hitting that armor at normal velocities. It’s clear for me that most artillery shells CAN’T penetrate the top armor of most tanks. Can the shrapnel penetrate it? I guess it can’t.

In the threat http://www.battlefront.com/discuss/Forum1/HTML/002839.html Bullethead wrote:

“I've read that the radiators of Tiger Is could be shredded by arty landing on the engine deck, although the engine itself and the rest of the tank usually survived basically unharmed. I've also seen an LAV survive a direct hit by a 122mm HE that hit at nearly plate normal to the front slope after falling from several miles up in the sky. Fortunately, this shell just broke up instead of exploding or neither I nor the exposed LAV crewmen would be here now.”

It seems armor wasn’t penetrated

It seems some people have destroyed PzKpfw IV or Panther with small caliber mortars (British 2 inch and American 60 mm). It seems to happen more often than not and IMHO it was impossible.

Sorry for my poor English.

Fernando J. Carrera Buil

[Kingfish]

Here's a simple test for you:

1) Find out the penetrative capability of a 25lbr fired in an indirect role

2) Find out the thickness of the engine covers for a Panther

If 1 is greater than 2 then there is your brew-up.

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

Charlie don't surf!

[Tanaka]

Olá Fernando,

Estou contigo no caso em que com base na velocidade, um projectil HE não consegue prefurar o topo do tanque... Mas quando ocorre o impacto o projectil rebenta, e origina estelhaços (astillazo)... Qual a energia cinetica destes estilhaços ? Mesmo que perfurem o topo do tanque... para o fazer explodir era precisso muita sorte.

João

[This message has been edited by Tanaka (edited 09-26-2000).]

[Jeff Duquette]

It is interesting that there is actually a debate on what the effect of a direct hit by a heavy caliber HE round would be on the upper deck or turret top of a tank. Its got noting to do with kinetic energy. The blast effect of a 105mm HE round alone would rupture 15mm of plate steel like it was a tin can.

It’s a case of lack of historical evidence to suggest a large percentage of tanks in WWII combat being damaged by indirect HE fire. Relative to tanks damaged\destroyed by direct fire, anti-tank mines, Air Attacks etc. those kills attributable to indirect HE fire are relatively small. This is a function of the inherent inaccuracy of artillery. Without very heavy concentrations of fire the probability of indirect fire landing smack dab on top of a tank are very low.

<BLOCKQUOTE>quote:</font><HR>

George Blacburns: The Guns of Normandy. Blackburn served as an F.O.O. in the 2nd Canadian Division, ETO, 1944.

They have about a dozen really big tanks (Panthers and Tigers) as well as about fifty Mark IVs in the two or three miles I can observe from our slit trench. But you never see them all at once, and there's a confusing number of derelict tanks lying about, both his and ours, knocked out during Goodwood. For a while we are right between his tanks on the left and ours coming up on the right. One of his with an 88-mm gun (probably a Tiger) is in a copse near the Caen—Falaise highway firing from a hull-down position. He's so bloody close – only about two hundred yards away - that each time he fires, the muzzle blast bangs our ears together and flattens the grain all around us as the shot screeches overhead and a shower of sparks goes up from one of our tanks up on the hill, which he keeps hitting until it brews up. The Typhoons aren't flying because of the rain. Anyway, the Tiger is too close. (Were much afraid of a Typhoon missing its target and hitting us.) So I put a battery of mediums (sic 25 pounder howitzers) on him and hammer him for about half an hour. (I may not have knocked him out, but I'll bet I loosened up the bowels of that crew.)

<HR></BLOCKQUOTE>

[Fernando]

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

Here's a simple test for you:

1) Find out the penetrative capability of a 25lbr fired in an indirect role

2) Find out the thickness of the engine covers for a Panther

If 1 is greater than 2 then there is your brew-up.

<HR></BLOCKQUOTE>

What does BTS think is the penetrating power of artillery or mortar shells? It seems 50 mm mortars can penetrate Panther top armor

AFAIK the enemy 25 pdr didn't get a "Weak spot penetration" but a "top penetration" so it penetrated the 16 mm armor. Could the 25 pdr penetrate it? A 25 pdr. HE shell can penetrate 73 mm (0º), 58 mm (30º) or 34 mm at (60º) at 100 meters (BTS dixit, check your CM game). Its muzzle velocity is 610 m/sec so I guess a shell velocity of about 600 m/sec at 100 meters is a good approximation. Let’s think the maximun height of a 25 pdr shell fired in an indirect role is about 1000 meters (I don’t know it for sure, it’s only a guess). The final velocity of the shell hitting the tank could be close to 200 m/sec (0º) or 240 m/sec (30º). It’s about 2.5-3 times smaller than the velocity of the same HE shell fired in a direct role so its kynetic energy is from 6.25 (hitting at 30º) to 9 (hitting at 0º) times smaller. I don’t know the exact correlation betwen kynetic energy and penetration power but I guess it’s not lineal. Let’s think it’s lineal (it helps your argument, not mine). If the HE shell fired in a direct role can penetrate 73 mm (hitting at 0º) then the HE shell fired in and indirect role (9 times less kynetic energy) can penetrate about 8mm, less than Panther’s 16 mm armor. If you hit it at 30º then the penetrating power of the HE shell fired in an indirect role is 58/6.25 = 9.28 mm. It’s still less than Panther’s 16 mm armor

Please notice I’ve used the CM data for the 25 pdr.

[Jarmo]

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

If the HE shell fired in a direct role can penetrate 73 mm (hitting at 0º) then the HE shell fired in and indirect role (9 times less kynetic energy) can penetrate about 8mm, less than Panther’s 16 mm armor. If you hit it at 30º then the penetrating power of the HE shell fired in an indirect role is 58/6.25 = 9.28 mm. It’s still less than Panther’s 16 mm armor<HR></BLOCKQUOTE>

Penetration cabability of HE shell does not directly correspond

to the velocity of the round. Although the velocity does matter.

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

Now, would this brilliant plan involve us climbing out of

our trenches and walking slowly towards the enemy sir?

[Kingfish]

<BLOCKQUOTE>quote:</font><HR>What's the hitting power/Kynetic energy of an artillery shell? AFAIK non-mortar shells couldn't hit top armor in a 0º angle and they hadn't the kinetic energy/velocity of an AP shell.<HR></BLOCKQUOTE>

True, they don't. But what the HE shell lacks in kinetic energy/velocity it makes up (to a certain extent) with the HE blast shockwave.

Also consider that the AP shell is hitting the toughest part of the tank, while the HE shell (in an indirect application) is hitting some of the weakest parts.

Let me re-phrase my simple test:

1) Find out the penetrative capability (kinetic energy of shell + effects of HE blast) of a 25lbr fired in an indirect role.

2) Find out the thickness of the various top sections (turret roof, drivers roof, engine covers)of a Panther

If 1 is greater than 2 then there is your brew-up

[CavScout]

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

Penetration cabability of HE shell does not directly correspond

to the velocity of the round. Although the velocity does matter.

<HR></BLOCKQUOTE>

I would think that in dealing with a HE shell, velocity is rather unimportant. HE dmage is going to be from blast.

Cav

[Guest rune]

If in doubt, look at the following site:

http://history.vif2.ru/destroyed/german.html

Lots of tanks there marked as destroyed by artillery. My favorite is a King Tiger knocked out by a 57mm At gun. [side shot]

Again, thanks to Valera for a great web site.

Rune

[Jarmo]

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

I would think that in dealing with a HE shell, velocity is rather unimportant. HE dmage is going to be from blast.

Cav<HR></BLOCKQUOTE>

Still has some importance, check any gun statistics how HE

penetration values go down as the range increases.

Not as fast as with AP, but down they go.

[Fernando]

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

Still has some importance, check any gun statistics how HE

penetration values go down as the range increases.

Not as fast as with AP, but down they go. <HR></BLOCKQUOTE>

Good point Jarmo.

That's the question then. If velocity is unimportant the why the HE penetration decreases as the range increases?

[Jarmo]

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

Good point Jarmo.

That's the question then. If velocity is unimportant the why the HE penetration decreases as the range increases?

<HR></BLOCKQUOTE>

But it doesn't decrease enough? 75mm infantry gun HE has 19mm penetration

at 2000 meters. With muzzle velocity of 260 m/s, the penetration

is 20mm at 100 meters.

105mm pack howitzer HE, (311m/s) penetrates 49mm at 100 meters and

40mm at 2000 meters. This would suggest (to me), that it would

penetrate at least 30mm when used as artillery.

That contradicts with the Guderian statement.

Does anyone know, at what angle arty shots fall? How important is

angle with HE?

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

Now, would this brilliant plan involve us climbing out of

our trenches and walking slowly towards the enemy sir?

[Fernando]

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

It is interesting that there is actually a debate on what the effect of a direct hit by a heavy caliber HE round would be on the upper deck or turret top of a tank. Its got noting to do with kinetic energy. The blast effect of a 105mm HE round alone would rupture 15mm of plate steel like it was a tin can.

<HR></BLOCKQUOTE>

It seems you're a civil engineer. Are you specializing in iron alloys? I'd like to get some hard data from you about the strenght of hardened steel plates to high explosives.

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

What's the hitting power/Kynetic energy of an artillery shell? AFAIK non-mortar shells couldn't hit top armor in a 0º angle and they hadn't the kinetic energy/velocity of an AP shell.<HR></BLOCKQUOTE>

True, they don't. But what the HE shell lacks in kinetic energy/velocity it makes up (to a certain extent) with the HE blast shockwave.

I like this kind of magic. There’re enought kynetic energy to penetrate top armor but HE blast magically appears and probides some of that hard needed kynetic energy. Can I ask how did it?

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

[quote

Also consider that the AP shell is hitting the toughest part of the tank, while the HE shell (in an indirect application) is hitting some of the weakest parts.

Let me re-phrase my simple test:

1) Find out the penetrative capability (kinetic energy of shell + effects of HE blast) of a 25lbr fired in an indirect role.

2) Find out the thickness of the various top sections (turret roof, drivers roof, engine covers)of a Panther

If 1 is greater than 2 then there is your brew-up

<HR></BLOCKQUOTE>

I tried to ask your questions but then you have reformulate them making them tougher to answer in the process. Most of the info about Panther armor are included on Jentz’s book but I’ll not dig it for you.

AFAIK you can add the HE blast energy to the kynetic energy shell but I may be wrong. If you are right then why didn’t the AP shells carry LOTS of HE explosive to improve their penetrative capabilities?

BTW I'm a bit amazed. Most people think I'm wrong but havwen't showed hard data about it in so far. I’m an amateur but I’ve show an official report about the Panther and some (very basic) data about kynetic energie wich I learned at school when I was a child about 25 years ago. I say artillery shells don’t have enought kynetic energy to penetrate Panther top armor and people don’t care to refute it and begin saying “kynetic energy doesn’t matter but blast effect does matter then. I’ve got any evidence but prove I’m wrong”. It’s a bit frustrating.

[Wild Bill Wilder]

Caballeros,

Comprendo muy bien su punto de vista tocante al efecto de las municiiones de la artilleria contra los tanques.

Cuando mencione' la reaccion de lost tanqueros, no me referi' al miedo, sino al peligro que las acompanaba.

Mi duda viene a causa de la disparidad que a menudo viene entre lo que las pruebas indican and lo que la realidad demuestra.

Pero no soy experto en el tema, de modo que me callo y sigo leyendo.

(Perdonen la falta de tildes en esta nota)

Guillermo el Salvaje

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

Wild Bill

Lead Tester

Scenario Design Team

Combat Mission-Beyond Overlord

billw@matrixgames.com

[Fernando]

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

But it doesn't decrease enough? 75mm infantry gun HE has 19mm penetration

at 2000 meters. With muzzle velocity of 260 m/s, the penetration is 20mm at 100 meters.

105mm pack howitzer HE, (311m/s) penetrates 49mm at 100 meters and 40mm at 2000 meters. This would suggest (to me), that it would

penetrate at least 30mm when used as artillery.

<HR></BLOCKQUOTE>

Yes, It looks a bit odd. I’ve compared the German 75mm infantry gun, 75 recoilles gun and 75 mm howitzer. All three have almost the same blast number (a combination of blast radious and blast strengh) but different penetrations closely related to their muzzle velocity:

75 infantry Gun: blast 35, muzzle velocity 260 m/sec, penetrates 20 mm at 100 meters

75 recoilles gun: blast 34, muzzle velocity 351 m/sec, penetrates 29 mm at 100 meters

75 mm Howitzer: blast 34, muzzle velocity 500 m/sec, penetrates 42 mm at 100 meters

Guns with a higher muzzle velocity have higher penetration power but they don’t lost it at longer ranges. It’s a bit odd

[Philistine]

Fernando,

This issue (to some extent) was disucssed before in the context of direct fire HE shells vs. direct fire AP shells and the relative effectiveness.

The thread is:

http://www.battlefront.com/discuss/Forum1/HTML/008482-2.html

In using your physics argument, you are neglecting both the forward velocity of the shell (which will be notrivial depending upon the range) and the kinetic energy of the explosion of the HE.

What follows is a long quote (of myself--sorry kind of cheesy ) from the above thread which does a VERY rough estimate that for a 75mm gun firing an HE shell, the majority of the Kinetic energy is provided by the explosion of the HE.

<BLOCKQUOTE>quote:</font><HR>Re: looking at this from a physics point of view. (Bear in mind I have no actual military service nor do I have any practical physics training other than a year and a half of college as a physics major before I decided that the humanaties were for me...So take this for what it's worth).

My calculation of the energy content of a kilogram of HE (TNT) is 4.2E6 Joules. (I get this by using the constant bandied about for the energy content of a megaton of TNT being 4.2E15 Joules and assume that 1 megaton=1E9 KG--not sure if megaton is metric ton or short ton or long ton, but I'm using metric tons b/c the math works much better )

.853 KG Amatol I'm going to assume = 1KG TNT (partly because I understand it was more explosive than TNT, but primariliy, because it makes the math easier [do you see a trend]).

Now, you had said that a 75mm German HE shell has a velocity of 550 m/s, which gives a KE of 3.025E5 Joules per Kilogram. Any idea of the the weight of the shell? (The weights given by Rattus seem to be on the order of 7 KG for shell, propellent & casing). Say, 4 KG for shell? (say it with me: "It makes the math easier")--for aprox. 1.2E6 Joules.

Which is approx. 35% of the energy provided by the HE payload.

Of course, a couple of caveat's -- HE (unless it is HEAT or similar) explodes in 360 degrees and the KE of the shell is only 1.2E6 J at the muzzle, it would fall of fairly rapidly with range.

Given all this, it seems that although the KE of the shell provides a significant portion of the KE, the major portion is provided by the HE (which seems reasonable, otherwise, why not just use solid shot at high velocity?)

Just playing with numbers here--the broadest back of the envelope things. I haven't checked this, or even really thought it out all that well, but that seems to be a trait hereabouts...

<HR></BLOCKQUOTE>

I don't know what energy level of HE will penetrate what level of armor, but I think your focus on the kinetic energy of an HE shell as being equivalent to dropping a brick weighing the same as an HE shell from 1000 meters is off.

Just my $.02

--Philistine

Edited to put in the URL

[This message has been edited by Philistine (edited 09-26-2000).]

[Thermopylae]

I don't think its the physics. Any explosive shell carrying 12.5 lbs of explosive detonating on a panther's top kills it, end of story. Its the fact that most WWII artillery use was not in the fire mission style of CM but in bombardments. When you are trying to drop shells all over a 5 mi sq box, its understandable that not many tanks are hit by shells that fall very unlikelyly onto their tops. Even bombardments againt armored positions did not tend to do much. However when a shell did make a diect hit, it almost always killed the tank. (modern example: The israeli armor on the Heights in the six days war suffered badly from arab artillery, much of which dated back to only slightly post WWII, mainly due to the small target area they had large forces operating in) In CM, you are condensing about 10-15 shells per minute into a relatively small box. This high ROF and small target area make it more likely that a shell will come and blow up on the top of a tank. I do however agree that a 60mm mortar round, (about the same explosive power as a hand grenade and a half) would not penetrate anything but the light vehicles and tanks.

[Fernando]

<BLOCKQUOTE>quote:</font><HR>Originally posted by Wild Bill Wilder:

Caballeros,

Comprendo muy bien su punto de vista tocante al efecto de las municiiones de la artilleria contra los tanques.

Cuando mencione' la reaccion de lost tanqueros, no me referi' al miedo, sino al peligro que las acompanaba.

Mi duda viene a causa de la disparidad que a menudo viene entre lo que las pruebas indican and lo que la realidad demuestra.

Pero no soy experto en el tema, de modo que me callo y sigo leyendo.

(Perdonen la falta de tildes en esta nota)

Guillermo el Salvaje

<HR></BLOCKQUOTE>

Your Spanish is much better than my English

Me gustaría que alguno de los pesos pesados del forum, es decir, gente de la que más sabe sobre el tema, participara en este tema aunque fuera a costa de destrozar mis argumentos. No me importaría en absoluto que demostraran que estoy totalmente equivocado con tal de que lo demostraran. CM es fantástico, el mejor wargame táctico que he jugado pero creo que es algo vivo que se puede modificar y mejorar más con la ayuda de todos. Yo he querido sacar el tema del efecto de los imapctosdel fuego indirecto de la artillería sobre los tanques pero no como una crítica al juego sino como intento de mejorarlo en la medida de mis posibilidades. Seguramente esté equivocado pero la discusión ayudará sin duda a que CM sea todavía mejor de lo que ya lo es ahora, que lo es y MUCHO.

[Banshee]

I went and dusted off my Jentz book (ok ok it's lying right next to my bed and I trip over it every night) and while it is a very good book I think there is quite a danger of adding so much emphasis to one report. Now I'm going to have to go through the whole dang book and find every time in which arty took out a tank (esp a Panther)

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

Veni, vidi, panzerschrecki

[Fernando]

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

I don't think its the physics. Any explosive shell carrying 12.5 lbs of explosive detonating on a panther's top kills it, end of story. <HR></BLOCKQUOTE>

I'd like to know if you're just guessing or you've some data to support your stattement.

Please remember Guderian's report about the Panther:

"The Panther is basically invulnerable to artillery fire. However, direct hits by calibers OVER 150 mm on the roof of the hull and turret had the effect of deforming the armor and causing internal damage. Hits by lighter caliber shells hitting the comander cupola and the roof armor showed no effect"

It seems he and his crews were wrong and you're right

[CavScout]

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

"The Panther is basically invulnerable to artillery fire. However, direct hits by calibers OVER 150 mm on the roof of the hull and turret had the effect of deforming the armor and causing internal damage. Hits by lighter caliber shells hitting the comander cupola and the roof armor showed no effect"

<HR></BLOCKQUOTE>

If no, or little, damage was done... how does one know what they were hit by?

Cav

[CavScout]

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

Please remember Guderian's report about the Panther:

"The Panther is basically invulnerable to artillery fire. However, direct hits by calibers OVER 150 mm on the roof of the hull and turret had the effect of deforming the armor and causing internal damage. Hits by lighter caliber shells hitting the comander cupola and the roof armor showed no effect"

<HR></BLOCKQUOTE>

Yeah, war time reports... reminds me of how "effective" the Patriots were in the Gulf...

Cav

[Banshee]

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

Yeah, war time reports... reminds me of how "effective" the Patriots were in the Gulf...

Cav

<HR></BLOCKQUOTE>

Just curious, I thought the Patriot was effective as a point defense weapon, It was just the mispreception that it was supposed to defend WIDE areas (whole cities as opposed to a small HQ or something like that). What did the reports say and what do you think were the patriots failings?

And I agree that way too much importance is given to this ONE report. If arty couldn't take out tanks what chance would aircraft guns have?

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

Veni, vidi, panzerschrecki