Jump to content
Sign in to follow this  
zyss

The original data and analysis of T-34-85 protection and firepower

Recommended Posts

Posted (edited)

Hi, developers, this is an article about T-34/76 and T-34-85 protection and 85mm gun firepower. I think it could help you for the "Tank Crews". Another article about the principle of armor piercing is at here:

 

 

 

Chapter 1 The T-34 armor quality

1-1 The dry cargo (original data) of T-34 armor test

In 20th and 21st July 1943, a T-34/76 (1941 or 1942 model) was used for firing trials of the Tiger I Kwk36 88mm gun. The tests are at a distance of 1500 meters, the results are shown in follow pictures:

651139205_Fig1-01Thephotosabout88mmshotT-34-76.jpg.7c0d6e2a33aa874a9bc449537a79433c.jpg

Fig 1-01 The photos about 88mm shot T-34/76

234561543_Fig1-02Thedetailsabout88mmshotT-34-76.jpg.b561f8f90e87a3cca075a58ce155b71a.jpg

Fig 1-02 The details about 88mm shot T-34/76

In table of Fig 1-02:

(1) The first column is the hit place in tank.

(2) The second column is the shells type.

(3) The third column is the armor thickness.

(4) The fourth column is the “Structural angle”, we can call it as “armor plate set angle”, which means the angle between the armor plate and the normal of the flat ground.

(5) The fifth column directly translation is "meeting angle", the real name is “complementary angle of the path angle”, which means the complementary angle between the gun direction and the hull front direction in horizontal flat, 70 degrees means gun shots from side with 20 degrees angle.

(6) The sixth column is the results.

 

Many peoples mistake the fifth column as the "normal angle" or "impact angle", it was a wrong view. One reason is, we could find the fifth column datas are almost 70 degrees, and the different armor plate had different “set angle”, so if the fifth column was the "impact angle", it means after every shot, the testers should move the tank accurately to let the " impact angle" was 70 degrees. Obviously, it was impossible; the other reason is, in the fourth column, the upper hull front “structural angle” is 40 degrees, and on the plain, the T-34 upper hull front is 60 degrees “structural angle”, that’s mean T-34 is on a 20 degrees downgrade in test. Then if testers want to take 70 degrees “impact angle”, they will shoot it from a very large angle from side, it was a meaningless way, because this test purpose was simulating the performance in actual combat.

 

The results are:

1. Turret ring, APCBC, 16 mm thickness, 0 degrees armor plate set angle, 20 degrees "side angle" with shell. Total penetration, turret is ripped off the tank, 130 mm long crack in turret skirt.

 

2. Glacis (Upper hull front), APCBC, 45 mm thickness, 40 degrees armor plate set angle, 20 degrees side angle, breach in armor, driver's hatch torn off, cracks in armor in length of 160-170 mm, shell ricocheted.

 

3. Nose part, APCBC, 45mm, 10 degrees armor plate set angle, 20 degrees side angle, penetration through, 160x90mm opening. Cracks in armor, 30-130-160mm length. Crack in weld seam, 300mm.

 

4. Nose "beam" (where UFP and LFP meets), APCBC, 140mm thickness, 0 degrees armor plate set angle, 15 degrees side angle, opening is 90x90mm, exit hole is 200x100mm.

 

5. Glacis, HE hit, 45mm thickness, 40 degrees armor plate set angle, 20 degrees side angle, insignificant dent, holding of frontal plate meeting with side armor skirt on the left side is destroyed.

 

Base on these results, Soviets thought that T-34/76 can be penetrated by kwk36 88mm gun at 1500m. It looks like that the T-34/76 armor is weak to against 88mm gun. But if we look at the results again, we will find many interesting things.

 

Let we see the three penetrated places at T-34/76, one is at turret ring, two are at “nose” area, all of them are the weak places at T-34/76. The HE also caused weld joint damaged. That’s why the T-34/85 had such changes:

(1) Turret ring up to 90mm.

(2) The meeting area of upper hull and lower hull had redesigned.

(3) The lower hull plate slope angle from 53 degrees to 60 degrees.

(4) Use the automatic submerged arc welding machine to deal the weld joint.

 

The hit which can prove the resistance of T-34/76 armor, is only the 2# shoot at the upper hull. Soviet put T-34 in adverse conditions, they are strict with T-34. So how did this hit? A piece of armor had cracked, but the shell ricocheted!!! The driver's hatch torn off by the ricocheted shell. Well, maybe only one shoot result can’t prove a certain resistance, but it can prove that the Kwk36 gun can’t 100% penetrate T-34/76 upper hull front armor at these conditions. The penetrate percent at these conditions, may be was 10%, or 90%. For ease of calculation, we suppose this shoot 100% penetrated the hull. So how the “impact angle” is? The 40 degrees armor plate set angle, 20 degrees side angle, if you know how to calculate it, you can get the “impact angle” is about 43°57′. Someone may think this angle is too overstate, OK, let’s suppose the writer who record these datas drink too much vodka, he recorded the fourth column as the angle between armor plate set and the flat ground. Then the T-34 is on a 10 degrees downgrade not 20 degrees, the “impact angle” is about 52°50′, now we will use the DeMarre formula to calculate the Kwk36 88mm gun penetration distance when the T-34 is at a flat ground.

 

DeMarre formula:

Vc=K*b^0.7*d^0.75/(m^0.5*cosα^n)

 

In the formula, “b” is armor thickness, “d” is the caliber of gun, b and d are commonly used for “cm (=10mm)”, Vc is the impact speed, calculated by “m/s”, and m is the mass of the projectile, calculated by “g”. “α” is the “impact angle”.

 

K is the armor anti-ballistic coefficient, it is a comprehensive coefficient representing the physical properties of the armor material, which should be determined by the firing test, it cannot be calculated according to a certain stress.

 

For vertical armor, n=0.7. For slope armor, the experimental results show that n>0.7, it is related to the relative thickness of Cb=b/d, armor type and the shape of projectile.

 

The recommended K values from datas are as follows:

Low carbon steel plate: 1530

Nickel steel plate: 1900

Generally homogeneous armor: 2000-2400 (the lower value is suitable for low carbon or medium hardness armor, while the higher value is suitable for high hardness thin armor)

Surface treated (face hardened) armor 2400-2600

 

For T-34 and Kwk36 gun:

“b” = 4.5cm

“d” = 8.8cm

“m” = 10200g

We don’t know the Vc at 1500m, but we know the vertical penetration of kwk36, and the shell velocity decrease is linear with distance, so we can calculate the velocity decrease rate every 100m.

2039396927_Fig1-03Theverticalpenetrationofkwk36.jpg.ff1de43ed47027e4ebb02e8f15304333.jpg

Fig 1-03 The vertical penetration of kwk36 (from Wiki)

Base on this table, we can calculate the velocity decrease rate is Vd9.1716m/s, so Vc at 1500m is 773-15*Vd=635.426m/s.

 

We know, more “K” value, less the “n” value, the 1/((cos60)^n) will less, the Vc value of penetrating 60 degrees armor velocity will less, the distance of Kwk36 penetrate T-34 will more far. We calculate the Vc by using unfavorable conditions for T-34. We set the “K” value as high as possible. The T-34 armor was high hardness armor, so we set the K=2400 in this equation.

 

Now let’s substitute the data in DeMarre formula:

When T-34 in Soviet test conditions:

635.426=2400*4.5 ^0.7*8.8 ^0.75/(10200 ^0.5*(cos52°50′) ^n)

We calculate the n1.1950

 

Now let’s substitute the data in DeMarre formula:

When T-34 at flat ground:

“α” = 60°

The formula changes to such equation:

Vc=2400*4.5^0.7*8.8^0.75/(10200^0.5*(cos60)^1.1950)≈796.62m/s

 

The PzGr. 39 (APCBC) Muzzle velocity is only 773m/s, that’s mean Kwk36 can’t penetrate the hull front armor when T-34 at flat ground.

 

Well, something was wrong. Where was the wrong? It is the Vc and the K value. The conditions which we supposed are based on 100% penetration, but the penetrate percent on penetration table always 50%, that’s mean the distance will more far than 100% penetration, the Vc will also less than 100%. And the K value of T-34 maybe higher than 2400. If the 50% penetration distance in Soviet Kwk36 test was at 1800m, the equation is:

635.426=2400*4.5 ^0.7*8.8 ^0.75/(10200 ^0.5*(cos52°50′) ^n)

We calculate the n1.107

Then the Vc of 60° impact is:

Vc=2400*4.5^0.7*8.8^0.75/(10200^0.5*(cos60)^1.1071)≈749.48m/s

That’s mean Kwk36 can penetrate it at 256m.

 

If the K=2800, the n0.801, the Vc≈707.28m/s, Kwk36 can penetrate it at 716m. Of course, K=2800 is looks like too high, but remember that, the K is “a comprehensive coefficient representing the physical properties of the armor material, which should be determined by the firing test, it cannot be calculated according to a certain stress.”

 

These two reasons let us has calculated an exaggerated result. But please noticed that, although the Vc=796.62m/s was exaggerated, but it also proved T-34 armor had a high resistance to Kwk36 gun. And when the K=2800 or higher, the n=0.801, the Vc will more reasonable, and is very close the datas in Tiger crew manual.

 

There are other original datas about T-34 armor, which came from German tank manuals:

980321461_Fig1-04aTheTigercrewmanualaboutT-34penetrateddistance1.thumb.jpg.d0ef57cae3557a9c69a40c755605ad3d.jpg

Fig 1-04a The Tiger crew manual about T-34 penetrated distance 1

83768673_Fig1-04bTheTigercrewmanualaboutT-34penetrateddistance2.thumb.jpg.0dcc38fb318a6cc22c344e203dd99451.jpg

Fig 1-04b The Tiger crew manual about T-34 penetrated distance 2

1214259227_Fig1-05ThePanthercrewmanualaboutT-34penetrateddistance.jpg.2dd0c3a1d4d8fda64eccd8db4dbb6ba5.jpg

Fig 1-05 The Panther crew manual about T-34 penetrated distance

680789711_Fig1-06ThePak40manualaboutT-34penetrateddistance.jpg.d8788b7f0e41d8c35ae78feaed2b298a.jpg

Fig 1-06 The Pak40 manual about T-34 penetrated distance

 

Fig 1-04, 1-05, 1-06 were some manuals of German tanks and gun, T-34A is normal type T-34/76, T-34B is the type with additional armor. Many people think German “animals” could easily penetrate T-34 upper hull front far than 2000m, but obviously fact was, German didn’t think their guns so power. In Tiger, Panther, Pak40 manual, the distances of penetrating T-34 upper hull front were 800m, 1000m, 100m. I think German had no reason to overstate the resistance of T-34 armor, and they also had no reason to use uncertain penetrate distance in tank and gun manuals. These distance datas were reliably, and the T-34 probably at flat ground, which mean the impact angle was 60 degrees.

 

There was also an original data about Soviet test Pak40 vs T-34 upper hull front:

(http://tankarchives.blogspot.com/2014/04/spare-track-links.html)

265202528_Fig1-07T-34sparetracktest.thumb.jpg.69fcf5909a26a2bc3eeb7d4cd970a6d9.jpg

Fig 1-07 T-34 spare track test

It shows that Pak40 can penetrate at 1000m, but can’t penetrate at 1100m. This data has no detailed angles and hits data, but refer to the test of Kwk36 vs T-34, Soviet also put T-34 in adverse conditions, and the “can’t penetrate” means 0% penetrate, so the “can penetrate at 1000m”, may means there was a low percent penetrate rate.

 

Compare with the original datas above, the inference of <WWII Ballistics- Armor and Gunnery> was so unreasonable and prejudiced. The author of <WWII Ballistics- Armor and Gunnery>, had no detailed shot datas, even no hit place details, and he used these uncertain “reports”, refer to American armor tests to inference T-34 upper hull front resistance of 75mm APCBC was 93mm. How unreasonable and prejudiced was.

 

The T-34 and M4 upper hull front resistance on German tank and gun manuals, may could explain why Soviet and American didn’t extensive increase T-34 and M4 hull armor. Different with German Panzer IV, the T-34 and M4 hull front armor resistance were enough to against most German guns. Don’t forget, the most German tank and anti-tank guns are Pak40 and Kwk40, for penetrating a T-34 at flat ground, if Pak 40 need 100m distance, the Kwk40 even can’t penetrate it, Panzer IV need to attack the turret ring or other “weak points” from front. And in Tiger crew manual, to penetrate T-34 and M4 hull front, both needed 800m distance. So Soviet and American only need to improve and increase T-34/ M4 turret armor, German had to design a new tank—Panther, because Panzer IV had so weak hull armor.

 

1-2 The improvement of T-34/76 and T-34/85 armor

The test of Kwk36 vs T-34/76 let Soviet knew what’s the problems in T-34 design and build, they improve them, let’s see the improvement on T-34/85 again:

(1) Turret ring up to 90mm.

(2) The meeting area of upper hull and lower hull had redesigned.

(3) The lower hull plate slope angle from 53 degrees to 60 degrees.

(4) Use the automatic submerged arc welding machine to deal the weld joint.

 

The automatic submerged arc welding machine was used not only in T-34/85 building, but also some late T-34/76 model 1943. Some pictures show that:

1097193239_Fig1-08BuildT-34-76.jpg.0b0d299d2e539b0bbabaf652c6c16b77.jpg

Fig 1-08 Build T-34-76

898004512_Fig1-09BuildT-34-85A.thumb.jpg.4de10d197acc0963c73d5f7f0d327efa.jpg

Fig 1-09 Build T-34-85 A

1643266201_Fig1-10BuildT-34-85B.thumb.jpg.ef1ab18b29026d8fe68a21aa78415776.jpg

Fig 1-10 Build T-34-85 B

2104238508_Fig1-11BuildT-34-85C.thumb.jpg.ca690db3bd3fec0b2033f185f0e8b43f.jpg

Fig 1-11 Build T-34-85 C

 

Except welding improvement, the heat treatment of armor also improved.

540222059_Fig1-12T-34-76armorproperty.thumb.jpg.0bbae1d78ef43f9f73158987c0401247.jpg

Fig 1-12 T-34-76 armor property

The fig 1-12 is came from “AD011426 < Review of Soviet ordnance metallurgy>”, the T-34 armor datas are based on the T-34 model 1943 which sent to Aberdeen Proving Grounds. The “Impact Energy V-Notch Charpy Ft. Lbs. at -40°F” was a data which could directly reflect the resistance of armor. We could see in T-34/76 model 1943, hull lower side, sponson floor, turret roof, bow casting had low “Impact Energy V-Notch Charpy”, the data of bow casting even was 2.2, that’s why it was so 140mm but could be penetrated by Kwk36 at 1500m. These parts of armor had a bad heat treatment because of decreasing man-hours.

 

Then let’s see how was the T-34/85 armor. In 1951, a captured T-34/85 was sent to American for testing, the results formed a report called “CIA-RDP81-01044R000100070001-4 <Engineering analysis of the Russian T34/85 tank>”. Unfortunately, because the hull had no big change, Americans didn’t test the “Impact Energy V-Notch Charpy” of T-34/85 hull armor, but they test the turret:

689239156_Fig1-13T-34-85turretarmorproperty.thumb.jpg.bbb0e6d60cb5bdcc393cebdca556dd71.jpg

Fig 1-13 T-34-85 turret armor property

Compare T-34/76 turret roof, T-34/85 turret top plate “Impact Energy V-Notch Charpy” from 5.5 up to 10, which show the improvement in armor heat treatment. And don’t forget, in most cases, the lower side armor, sponson floor armor are more important than turret top armor, so this improvement also proved that the heat treatment of T-34/85 lower side and sponson floor armor had improved.

 

1-3 The change of Americans views about Soviet high hardness armor resistance

American views about Soviet high hardness armor also changed when they test T-34/85.

In AD011426, Americans think:

“The very high hardness encountered in most Soviet tank armor has caused much unnecessary concern regarding the relative ballistic performance of the hard Soviet armor and the softer American armor.”

 

“Competitive ballistic triale which have been condacted at ordnance proving grounds on both very hard beyond question of doubt that in many cases, representative of actual battlefield attack conditions, very hard armor is distinctly inferior in resistacne to penetration as compared to armor of more convertional hardness.”

904249909_Fig1-14AD011426Sovietarmorviews.thumb.jpg.cc306c4c4cc8390c0d4ab87c25ce1fc7.jpg

Fig 1-14 AD011426 Soviet armor views

 

But in < Engineering analysis of the Russian T34/85 tank >, Americans think:

“The flat sloping armor in the front could be expected to provide desirable shell deflection properties.”

 

“Alloying materials had been effectively used to obtain toughness along with the desired hardness. The armor, for example, was much harder than our specifications call form yet at the same time tougher.”

5506662_Fig1-15EngineeringanalysisoftheRussianT34-85tankarmorviews1.thumb.jpg.c65e05015063eba4f4f38fe7e129d865.jpg

Fig 1-15 <Engineering analysis of the Russian T34-85 tank> armor views 1

1709660819_Fig1-16EngineeringanalysisoftheRussianT34-85tankarmorviews2.thumb.jpg.132045d07edc7af43ce83ca34a2bc579.jpg

Fig 1-16 <Engineering analysis of the Russian T34-85 tank> armor views 2

 

Obviously, in 1951, Americans realized that their high hardness armor had a low performance, and can’t treat as same as Soviet high hardness armor.

 

Soviets also negated American views about their high hardness armor, in the report “"Minutes of the meeting on the question of the evaluation of T-34 and KV tanks by Americans", CAMD RF 38-11355-360”, a transport link is:

http://tankarchives.blogspot.com/2013/04/aberdeen-t-34-and-kv-1-test.html

In this data, Soviets said: “The Americans insist that the T-34 and KV tanks' plates are hardened shallowly, and most of the armour is soft steel. They suggest that we change the hardening technology, which will increase the armour's resistance to impacts. This opinion has no basis in reality, and was likely caused by poor analysis of the armour.”

 

Clearly, the resistance of T-34 armor was not a “93mm” joking level, it is higher than most people think. The only problem was, for example, although the Pak40 could only penetrate the upper hull front at 100m, but when T-34 at a downgrade conditions, the resistance will decrease many. The weak places on turret also can be penetrated by Pak40 from far than 100m, although these weak places not so easy to hit.

 

Most people often ignore that, the T-34/85 had the best side armor in WWII medium tanks (except “Jumbo” “Assault tank”, which more like a heavy tank), the designer make T-34/85 as a “Offensive tank”, they need considering the front 60 degrees and side resistance, the 75mm thickness turret side had a well resistance even more than Tiger I, and the turret and hull had a well bulletproof shape, you could hardly find weak points on each side. Compared T-34/85, Panther turret side looks like a paper, in combat, 45mm anti-tank gun could easy penetrate it at a not so near distance. T-34/85 turret rotate speed is 25°/s, was the fastest speed in WWII tanks, could make sure that its gun quickly directing the targets in large front area range, this is very important in “offensive”.

 

In < Finnish Impressions of the T-34-85>, had evaluations about T-34/85 in armor, guns, engine and others.

(the link is:

http://tankarchives.blogspot.com/search?q=Finnish+Impressions+of+the+T-34-85)

How did it said T-34/85 armor?

"Armour: the armour is mostly the same design and same thickness. The hull in general has no advantages over the precursor. The turret is roomier. The armour is improved in the front. It resists 47-75 mm guns well at medium and long range. The sharper shape of the front increases the chance that armour piercing shells will ricochet. The quality of armour is higher than on the model 1943 tank.”

 

1-4 The quality of German tanks armor

Many people think that most of German tanks in WWII had a high quality armor. But is that true? Let’s see some original datas about Panther armor:

1670208359_Fig1-17Pantherarmorproperty1.thumb.jpg.7b2412cd2a0834b0cfb6683ebecf6f40.jpg

Fig 1-17 Panther armor property 1

In fig 1-17, we can see that the Panther upper hull side armor (52mm) “V-Notch Charpy Impact Energy at -40°F” was 2.2-3.2 Ft. Lbs., this is so bad as T-34/76 bow casting. Americans heat treatment this armor again, the data is:

1681707743_Fig1-18Pantherarmorproperty2.thumb.jpg.3914f763ab9fbfe7788040fca2d03d5c.jpg

Fig 1-18 Panther armor property 2

Well, the V-Notch Charpy Impact Energy had a little increase, but it still less than T-34/76 lower hull side, which had not good heat treatment in building.

 

In fact, in WWII, Germans still walking on a wrong way of heat treatment and armor elements using. Only Tiger I armor had the nickel (Ni) element, other type tank armor had none of this important element.

 

And many people also think the Soviet tests on German tanks armor are unfair, they claim that the trials should not count because of two things: one is that certain parts of the tank (such as guns, optical devices, etc) are removed from the tank prior to testing and the other is that the tanks' plates are hit several times over the duration of the test.

 

A title can explain these things:

http://tankarchives.blogspot.com/2015/04/common-questions-unfair-testing.html

 

First: multiple hits per plate. This test simply represents the harsh realities of war. Rarely, if ever, are tank battles one on one encounters where only one shot is fired. Usually you are facing a battery of guns or a platoon of tanks that will all fire at the same time, and they will do without being gentlemen and letting the other party reload. Of course, you will get some instances where a section that was compromised by previous hits is penetrated, but, at least in the case of Soviet tests, this is plainly noted in the document.

 

423666595_Fig1-19Pantherdestoried.jpg.da6ee405651162b7a7acbc491cd78e71.jpg

Fig 1-19 Panther destoried

632802231_Fig1-20KV1hits.jpg.35f35277f0d11ae13a32bfb660e1b279.jpg

Fig 1-20 KV1 hits

2130683461_Fig1-21Panthertest.jpg.57579d8c62ebe8f2be8644ad3e9b048e.jpg

Fig 1-21 Panther test

125525799_Fig1-22Tigerdestoried.jpg.ae5c0620cae1b3eabb983e4a350c604a.jpg

Fig 1-22 Tiger destoried

1305034412_Fig1-23T-34-76test1.thumb.jpg.2ab59b5c02455899ff46828f82534a90.jpg

Fig 1-23 T-34-76 test 1

 

1809131450_Fig1-24T-34-76test2a.thumb.jpg.4b33920ed8b23317c213ecfd064910fe.jpg 

Fig 1-24 T-34-76 test 2

1568768097_Fig1-25M4test.jpg.e5803a93766f3f2f18c3daabbaabe068.jpg

Fig 1-25 M4 test

 

Now for the next part: removing components before testing. You can see that some components are missing from the vehicles above: guns, vision blocks, etc. This is also caused by harsh reality. When you capture an enemy vehicle, everyone wants a piece: the artillerymen, the optics scientists, the electricians, the mechanics. By the time the tank reaches the range, odds are it will be stripped of any components other than the hull, since nothing inside will survive the rigorous testing displayed above. Sometimes you don't even get an entire tank. Nevertheless, this is another reality of life and simply how everyone tested.

595635062_Fig1-26T-34-85Mtest.png.4d79e84788534e088035dd463908f98d.png

Fig 1-26 T-34-85M test. The tank is simply an empty hull with just enough wheels attached to get it to the range.

916538223_Fig1-27Shermanballistictest.jpg.10859d0e3e2d977fbfb04e20839d14b7.jpg

Fig 1-27 Sherman ballistic test

1228253936_Fig1-28Object701test.png.d87885bab1bcaff6fb4cc4f5db7ff7de.png

Fig 1-28 Object 701 test

 

A trial about Panzer III armor test could show how the German armor was:

http://tankarchives.blogspot.com/2014/02/pziii-armour.html

 

Obviously, not only German tanks got multiple hits in Soviet test, not only German tanks removing components before testing. Soviet also test their tanks at same ways. But only German tanks armor had a poor performance at same conditions, which also prove the poor quality of German tanks armor.

 

 

 

 

Chapter 2 The T-34/85 firepower

2-1 The dry cargo (original data) of 85mm gun test

One famous test of Tiger I in Kubinka was the 85mm gun shooting, the 1000m penetrate distance became a well-known result of 85mm series gun. Someone think it was 90 degrees “impact angle”, so considering the “side angle”, they said 85mm gun could penetrate Tiger I upper hull front at only 500-800m in actual combat. Now let’s see what’s the details of the 85mm gun test:

192749914_Fig2-01a85mm800mpenetrateTigerlowerhullsidetwice.jpg.a499123fb9d375ca3b0ecb29c2137aaf.jpg

Fig 2-01a 85mm 800m penetrate Tiger lower hull side twice

2013522706_Fig2-01b85mm1450mpenetrateTigerlowerhullside.jpg.9659d554b2891a6c3f90be10abb93d02.jpg

Fig 2-01b 85mm 1450m penetrate Tiger lower hull side

1911169440_Fig2-01c85mm1000mpenetrateTigerupperhullfront.jpg.18cec8c574ad6eb2360d2be0d998a90c.jpg

Fig 2-01c 85mm 1000m penetrate Tiger upper hull front

517938910_Fig2-01d85mm1500mpenetrateTigerlowerhullfront.jpg.187d5dea18e1f9efd575850e7d702e45.jpg

Fig 2-01d 85mm 1500m penetrate Tiger lower hull front

619659774_Fig2-01eDetailsof85mmgunshootTiger.jpg.0115f8cd1debdf6914b3940c5768687e.jpg

Fig 2-01e Details of 85mm gun shoot Tiger

In Fig 2-01e, the armor plate set angle of upper and lower hull front were 27 degrees and 5 degrees, we also know that the angle of them on  flat ground were 8 degrees and 27 degrees, considering a certain amount of error in measure, the Tiger I was at a certainly about 19-20 degrees upgrade status. OK, we could see that Soviet are strict with their weapons, in the test of Kwk36 shot T-34, they let T-34 in adverse conditions, and in the test of 85mm gun shot Tiger I, they let their 85mm gun in adverse conditions. Then how the “impact angle” in this shot? The 27 degrees armor plate set angle, 30 degrees side angle, means the “impact angle” was about 39°30′. Well, the 85mm gun could penetrate Tiger I upper hull front far than 1000m from 60 degrees front range.

 

The penetration at Tiger I lower hull side also proved 85mm gun firepower, this shot penetrated in one side, and penetrated out from other side, and in Soviet official data, the 85mm APBC penetration at 500m was 110mm, and the two Tiger I lower side hull plates were 124mm thickness.

 

These results proved two things: one was, in actual combat, the penetration performance of 85mm gun APBC shell was more better than the “penetration tables”, and it had well performance on penetrating large angle sloped armor; the other one was, compared the Soviet armor and penetration standards, the Tiger I armor quality performed not as well as Soviet.

 

It’s not means that the Tiger I was easy penetrated in actual combat. Because the upper hull area was not a very large place at Tiger I front, the lower hull front often had spare track link at later version Tiger I, the most area of turret front superimposed thickness was more than 120mm. And the most important thing was, Germans used Tiger I as a “sniper” in most time, if they use it as a “attacker” as T-34, Tiger I would very easy lost in 1944-1945 battles.

 

 

2-2 The accuracy of 85mm gun

In 1944, a captured King Tiger was trailed in Kubinka, one result was the KwK43 88mm L71 gun had same accuracy with D-25T 122mm gun, which showed the well accuracy of Soviet guns. Then how about 85mm guns on T-34/85? There are some original datas:

1719190821_Fig2-02Detailsof122mmBR-471Baccuracy.thumb.jpg.4b69be72abc9c4aec0909af2d8dcdcfc.jpg

Fig 2-02 Details of 122mm BR-471B accuracy

504767917_Fig2-03Detailsof85mmBR-365(A)accuracy.jpg.77c08eb589a09adce4bcaaed888a9818.jpg

Fig 2-03 Details of 85mm BR-365(A) accuracy

 

In fig 2-02 and 2-03, the last but two and last but one columns are the vertical dispersion and horizontal dispersion, we can see that the 85mm APBC had 0.2m×0.3m dispersion at 1000m, better than 122mm APBC 0.3m×0.3m performance.

 

Someone will say Germans had better quality and large magnification aiming telescope. But we should know one thing, Soviet use Zeiss optics technologies to build their telescopes, these technologies are import at the time of “Soviet-German honeymoon period” before WWII. Americans and UK also gave well evaluations about the telescope on T-34/76 which had been sent for testing. The quality of Soviet telescopes was good.

 

Then let’s see the magnification:

635527942_Fig2-04Germantelescopesmagnification.jpg.4ea087e2510a120efb37784a9c403f68.jpg

Fig 2-04 German telescopes magnification

1362491585_Fig2-05Soviettelescopesmagnification.jpg.f3baaf408019e6294a40b53cbc495b4e.jpg

Fig 2-05 Soviet telescopes magnification

403150743_Fig2-06USandUKtelescopesmagnification.jpg.eaeccc5d9fc3ab141c904d7a623588fd.jpg

Fig 2-06 US and UK telescopes magnification

 

We can see that the advantage of German “animals” telescopes not the magnification, is the visual field, and the capacity of changing between 2.5X and 5X. The only exception was the telescope of T-34/85, Soviet designer select a balance point between magnification and visual field, compared the 5X magnification, the 4X magnification had very small gap but wider visual field.

 

The German telescopes often need a wide visual field, the reason was not the German had well technologies in building telescopes, just because German tanks had not a well visual field in late wars.

 

OK, maybe someone still think the numbers can’t prove anything, there is a test of Zis-s-53 on T-44:

434361561_Fig2-07Detailsof85mmgunaccuracyinT-44.thumb.jpg.bc6894eecbb4580aa104130fe79ed760.jpg

Fig 2-07 Details of 85mm gun accuracy in T-44

In this table, the T-44 use the Tsh-15 telescope, the different between Tsh-15 and Tsh-16 was the Tsh-16 had electrical heating for demisting. The target on the front sector area, crews don’t know where and how far the targets were. The results were clearly, the accuracy was 100% at 1000m, even rough aiming by using the electric turn motor.

 

In < Finnish Impressions of the T-34-85> said:

“Observation devices: the refractive telescopic sight is greatly superior to the sight of the model 1942-1943 T-34 tank. The clarity of the sight is on the level of the German 75 mm model 1940 gun. The field of view was increased by 15%. The markings are more convenient when firing on tanks up to 1000 meters. Injury during motion is nearly impossible due to comfortable pads. The periscopic observation device is simple, has a clear glass block, and is convenient to use. The commander's cupola allows the commander to observe the battlefield, and the turret traverse mechanism is a positive influence on the gunner's target acquisition.”

 

 

2-3 The visual field of T-34/85

The T-34/76 and KV-1 had no commander tower, so many peoples think all of Soviet WWII tanks had a bad visual field, that’s was wrong. If you compare T-34/85, JS-2, Sherman with German tanks, you will find that German tanks had bad visual field than Allies later war tanks. Don’t know why? Let’s analyze it.

 

On T-34/85 turret, commander, gunner, loader everyone had a periscope, this periscope could turn 360 degrees, and could put up and down in a range for looking up and down. On turret each side, there was a watch split for gunner and loader. Commander had a tower, except the periscope on top, the tower had 5 watch splits. The tower had two types hatch, the early type was two semi-circle parts, the later type was one big part. Both of two types hatch could turn 360 degrees, the periscope on hatch also could be turned follow the hatch turning. The visual equipment on T-34/85 turret could give crews very convenient conditions for watching outside, searching and locking the target.

 

But how “animals” were? For example, Tiger I, commander had a tower, 7 watch splits, in mid version, for keeping commander’s safety, 7 periscopes instead the watch splits, but it was only a substitute for watch splits. 360 degrees turn periscope? No. Gunner and loader periscope? No. Only in late version, Tiger I loader had a periscope, but can’t turn. The gunner, still no any periscope for watching, the only visual equipment was the watch splits on turret left side. In fact, in most WWII German tanks, only commander had visual equipment, gunner and loader even had no watch split. That’s why German telescopes had wide visual field, because gunners need to use it for watching, searching, locking targets. But we know, the visual field of telescope was still small, and gunners also can’t turn turret left and right quick just for taking a watch, so the efficiency of German tanks watching was still low in later wars. Some Sherman crews recalls that, the Sherman could cost little time from search to lock target, but Panther may cost over 25s. This saying maybe not very exactly, but it could prove the low efficiency of German tanks watching.

 

In < Finnish Impressions of the T-34-85> said:

“Armament: the 85 mm gun is a compact tank gun, identical to the German 88 mm tank gun in main parameters, losing out slightly in range and trajectory due to superior quality of German gunpowder. Compared to the 75 mm tank gun, the new Soviet gun has superior armour piercing and high explosive capability. The design of the gun is very good. It is smaller than the German 75 and 88 mm guns. The design is simple. It surpasses the 76 mm gun in flat shot range by 1.5-2 times.”

 

“Conclusions: the new T-34 tank is significantly different from the previous model, not only in armament, but in terms of general combat characteristics. Drawbacks of this tank include the control system, suspension, and transmission. Currently, this type of tank is one of the best medium tanks, on par with new German tanks.”

 

T-34/85 was not a simple 85mm gun upgrade of T-34/76, Soviets learn from the war and use the experience in improving their tanks, when German walking on the ways of too thick armor and powerful guns, Soviets were improving their tanks more reliable, better quality, and better combat efficiency of the crews.

 

 

 

 

Chapter 3 Some prejudices and rumours about T-34

1. The prejudices of “Western views”

People thinks American and “Western” tests and reports were puritanical and fair. In some cases, it was. As long as it is a human being, there will be subjective consciousness. Of course, many “Western” tests and reports were puritanical and fair than others, but no one could keep absolute puritanical and fair.

 

Except the prejudices of Soviet high hardness armor, there are other two examples in <Engineering Analysis of the Russian T34/85 tank>, the first one was the air filter of engine, the other one was gearbox.

 

Americans thought that the engine air cleaner of T-34/85 was low efficiency and may case problems, but the reason was very interest, they looked at structure of air filter, found it was outdated and less dust in it, so they had the conclusion, without any test. Well, even if the air filter of T-34/85 had low efficiency, but is it not enough for use? Not to mention that the air cleaner maybe had a well efficiency. The same thing happened on gearbox, Americans found the structure of T-34/85 gearbox was outdated and some gears heat treatment not well, so they evaluate it not well.

 

In < Finnish Impressions of the T-34-85 > said:

“Power plant: the diesel engine is the same type, but more carefully produced, is 20-30 hp more powerful, and has a longer lifespan under medium loads. The oil system is of the same type, but oil consumption is reduced by 30-40%. The exhaust is less smoky. The air filter does its job. In the summer, the diesel engine overheats less, in the winter, it starts more easily. The electrical equipment has isolated copper wiring.”

 

And there is an initial data which the 6th Guards Tank Army discovered the following lifespans of their tank engine and power system:

1990671029_Fig3-01T-34reliability.jpg.23b4368f3adbbe28e68e48516b6da31b.jpg

Fig 3-01 T-34 reliability

In this data:

“T-34: 2000-2500 km, 250-300 hours

IS/ISU-122: 1200-1800 km, 230-280 hours

M4A2: 2000-2500 km, 250-300 hours

SU-76: 1200-1800 km, 180-200 hours

Individual tanks made it as far as 3000 km, and their motors functioned for 300-350 hours.”

 

The other famous thing was the air filter in T-34/76 which be sent to Aberdeen. We should notice one thing first, the air filter in T-34/85 was a new model with well efficiency, it was different with T-34/76. And in Aberdeen, after traveling 343 km, T-34/76 1943 model was disabled by the breakdown of the V-2 diesel engine. The Americans are of the opinion that this was caused by a poor air filter on the diesel engine.

 

The T-34 sent to America had an air filter of the “Pomon” type. This filter was installed on T-34 and BT tanks. If properly cleaned and supplied with oil (in exceptionally dusty environments, this must be done once every 2-3 hours), the “Pomon” filter guarantees normal engine operation with 79.6% air purity at air dustiness of 1 gram per cubic meter. The filter at Aberdeen was not cleaned [Note: the filter was also not oiled. The Americans wonder why the filter is called "oily" by the Soviets in their impressions], which led to uncharacteristic engine wear.

 

Obviously, the reason of this T-34/76 broke down was not cleaned and oiled, but a lot of people said the reason was the poor efficiency and T-34s (include T-34/85) were unreliable. A typical “Western prejudices views”.

 

2. The lost numbers and “rush by numbers”

When we see the lost of Soviet AFVs (Armored Fighting Vehicles), we will amazing that so much the number was, and think Soviet had forever lost so much AFVs and mans. But this is a wrong view.

 

What is the truth? How Soviet counted the AFV lost? The vehicles broken in marching, it was lost, the vehicle was shut down by enemies but can be repaired, it was lost, even the vehicles out of fuel in marching, it was also lost. The vehicles can't work in action, it was the lost, this was the standard of Soviet “lost”. So, the number of Soviet “lost” not the “true lost” or “forever lost”, many of them are not cause by enemies, or broken in battle but can be repaired, most of them are "lost" more than twice even three times.

 

A book could show this:

<РОССИЯ И СССР В ВОЙНАХ XX ВЕКА ПОТЕРИ ВООРУЖЕННЫХ СИЛ Статистическое исследование>, Под общей редакцией кандидата военных наук, профессора АВН генерал-полковника Г. Ф. Кривошеева, МОСКВА “ОЛМА-ПРЕСС”, 2001.

 

In this book said, in 1944, only 24.6% Soviet AFVs lost are "true lost", and in 1945, it was 14.7%.

 

And as many peoples thinks, Soviet won by numbers, it is true in some cases, but please remember, only the numbers and rushing can’t win, it just sent the experience and records to enemy. In fact, from 1943, Soviet had shortage of mans, if you see the data about Eastern campaigns, you will find in most campaigns, Soviet “numbers” of tanks were 1.2-1.5 rate to German, in sometimes, Soviet had less tanks than German. The shortage of mans, and the resources cost limited Soviet numbers of AFVs, there are a group interesting date about it:

In 1943.01.01, Soviet has about 20600 AFVs, about 8100 service in front line.

In 1944.01.01, Soviet has about 24400 AFVs, about 5800 service in front line.

In 1945.01.01, Soviet has about 35400 AFVs, about 8300 service in front line.

In 1945.05.09, Soviet has about 35200 AFVs, about 8100 service in front line.

These data mean, for Soviet army, one crew group, had four tanks ready for them, if I’m a Soviet general, I will cherish my crews and soldiers more than tanks and other equipment.

 

3. The ergonomic of T-34

A mainstream of view about T-34 is its ergonomic was bad. This view is not all right. The most comfortless maybe the driver of T-34, but if you had got in T-34, JS-2 and T-54, you will know that the driver in T-34 is more comfortable than other two tanks.

 

The reason of bad ergonomic about driver in Soviet tanks, is the pursuit of low hull height. The low hull height let driver keep a comfortless posture in tank.

 

But that’s not mean the crews in turret are same. In fact, if put cutaway drawings of T-34/85, Sherman, Panther in same scale, you will find the space of T-34/85 crews even more than most medium tanks. The most tanks in WWII had a transmission axis in floor, this design occupied the space of fighting compartment, and let the height of hull become high, but Soviet tanks no. Maybe only Tiger I and II had larger turret space than T-34/85. Some tanks, like Panzer IV, its turret space even less than T-34/76, the crews in it also had a bad ergonomic than T-34/76. The Panther’s loader, had a crowded space for loading, it influence the efficiency of loading.

 

The designer of T-34/85 still try to improve the ergonomic in T-34. In T-34/85, for driver, an overcenter spring for main clutch reduced the foot pedal pressure required to disengage it; and in turret, there is a mechanism to help loader in loading ammos, loader could easy load the ammos from the turret back ammunition rack into bore, just sit in his seat and need not to move. In < Engineering Analysis of the Russian T34/85 tank >, Americans also praised the improvements in convenience of crews.

 

4. The lost rate of crews and bad performance in Korea

The report of American in Korea let people think the T-34/85 crews had a high lost rate after penetrated, this is a one-sided view. There are two reasons for that: the one is the lost reason not only the penetration, if crews escape from tank but killed by infantries or tank machineguns, it was also “lost”; the other reason is American crews will shoot the target many times after it had been destroyed in Korea, the multiple shooting let crews had a less chance to escape after penetrated.

 

Another view is the Sherman had water jacket, and Soviet no. We should know that, the water jacket will decrease the influence of the fire after penetrating, not mean the shell hit the ammunition rack won’t explode, if the shell hit the water jacket, the steam may cause more problem. And for T-34/85, most ammos are in the floor below the turret, a place which is the hardest to hit after penetrating. The diesel oil tank in hull side also ensure that the fire won’t burn to sky like the petrol. And the most American and German tanks, the oil tank is in floor, the ammos at the hull side or near the basket of the turret, were more dangers than T-34.

 

Many pictures show that the tanks had terrible destroyed by fire or explode, but we need to know that, most of these tanks, won’t burning serious or explode at once after penetrated, crews often had some time to escape, a terrible destroyed tank not means the crews all lost. Even in sometimes, the tank in pictures were deliberate destroyed to a terrible status, just for “the effects of publicity”.

 

A table contains total losses in the 5th Tank Corps during the Rezhitsa-Dvinsk Offensive Operation (July 18-28th, 1944) could prove something, the detailed data could be found in:

http://tankarchives.blogspot.com/2016/03/tank-crew-losses.html

The table had both of T-34/76 and T-34/85, figures gathered from American medium tanks (presumably Shermans of various makes) let us compare the safety of the T-34 series to that of the Sherman. The radio operator is in a lot more danger (27.3% vs 10%), but the loader is in a lot less (39% vs 21.4%). The rest of the figures are comparable. Overall, 24.6% of the Shermans' crews died when their tank was destroyed, compared to about 28% of T-34 crewmen of both types (the nature of the Soviet chart makes it difficult to calculate the exact percentage), because T-34/76 is 4 crews, T-34/85 is 5 crews, the rate of T-34/76 is up 28%, T-34/85 is below 28%.

 

Well, I think this comparison can explain many things.

 

The exchange rate of T-34/85 in Korea was also bad, but it means T-34/85 is a bad tank? No. Compared Americans, North Korea had a bad war system, they had control of the air, bad cooperation between tanks and infantries, and the important thing is, although many North Korea crews were return from Soviet, but they fighting formalist, they don’t know how to flexible application of the knowledge and tactics. Look at their parade step, then compare the using and results of M1A1 between US and Iraqi Government Army, you will know why North Korea were defeated by US, but Chinese put the front line to “The 38th Parallel”.

 

5. Using hammer to shift gears

This was the most absurd view, if you had got into a tank, you will find it is very hard to shake a hammer in driver seat. This rumours was came from a story of KV1, in early type, KV1 the rod of shift often jammed, so the driver using a hammer to take a knock, then it will work well. But it was impossible of using hammer to shift gears.

 

6. The “advanced” technologies will have a well performance

Most of us think the “advanced” technologies will help weapons have a well performance, even roll the weapons which using the “outdate” technologies. In some cases, it is right. But most of us also forgot that, how “advanced” is suitable, and does “advanced” must case a well performance?

 

Take the gearbox as example. At first, we should know the three forms of tank turn:

(1) Gradual turns

Two tracks run at different speed, then tank will turn to the side which has a low speed. The turn axis is out the tank, and the turn radius is large than other forms.

(2) Sharp turns

One side track moves forward or back, the other side track braked and don’t run, the tank will turn the braked side. The turn axis is in the middle of braked track. The turn radius is very small.

(3) Pivot turns

One side track moves forward, the other side track move back. The turn axis is in the middle of tank. The turn radius is minimum.

 

Then, let’s see the gearbox of T-34 series first, which was deemed to outdated structure by Americans. The T-34 has two levers at driver’s left and right, for control left and right track. When control the tank make a turn, driver need to pull the lever at the side which he wants to turn. At the first half range, the lever controls the clutch in that side; at the second half range, the lever controls the brake in that side.

 

This structure is simple and reliable, tank drivers could use it to do “sharp turns” and “gradual turns”. Because it could directly control each side clutch and brake, it could do many complex operations, which could help the tank has a well maneuverability in combat. But in “gradual turns”, the power will has some lost, because there is only one side track link to engine, the other side track will had resistance from ground. This type gearbox is easy for training the drivers who came from the tractor driver. But it still a different gearbox with the tractor. If a driver wants to become a “good” driver, he needs many experience and hard training, compare to Sherman or Panther drivers, that’s not an easy way.

 

Then let’s see the Sherman. Dmitriy Loza, who was the Hero of the Soviet Union, a Sherman tank commander in Soviet, in his book < Commanding the Red Army's Sherman Tanks>, he said that:

“It is easy to say, "Offload the tanks!" But how was this to be accomplished without any loading platform? Our first obstacle. And after this, another obstacle, no less troubling. The Sherman turned by using both differentials. This tank could not easily turn "on a dime," to rotate 90 or 180 degrees, not a problem for the Soviet T-34. The American tank required a significant area to turn around. How could this be accomplished on a flatcar? The front staff representative was in a hurry to get us offloaded. Apparently, the situation at the front demanded the immediate introduction of fresh reserves.”

 

Well, the Sherman which Americans aided was M4A2, I don’t know how many types Sherman can’t do a “Sharp turns”, but the M4A2 can’t. Of course, M4A2 can’t do a “Sharp turns” not means its turn radius is very large, but obviously, its maneuverability in a cabined place will be poor, like narrow streets. That’s the “advanced” structure of American gearbox, although it may be easy handled, but not a right equipment for tanks.

 

Then let’s see Panther. Panther and most of “Animals” used a “Double flow drive” (maybe called this name) gearbox, which let the tank could do “Gradual turns”, “Sharp turns”, “Pivot turns”, and it lost less power in turns. This type gearbox was very advanced in structure and technology, but it was too “advanced” in WWII, it was only saw at WWII German tanks, and after that, no tank used it, until in the third generation main battle tanks. Although Panther gearbox looks like had a well performance in maneuverability, but in combat, it was very unreliable. The Panther final driver also had bad quality, its life span was only 150km. Then if driver want tank work well, he should not do a “Pivot turns”, even can’t turn in fall back. Finally, the “advanced” technology didn’t give Panther “advanced” performance in battle.

Edited by zyss
  • Thanks 4
  • Upvote 1

Share this post


Link to post
Share on other sites

Looks really interesting, will devote some time to read this.  Thanks

Share this post


Link to post
Share on other sites

Germans include side angles of 30 deg in their maximum kill distances.

Meaning a Kwk 42 can kill a T-34 up to 800m, even when angled. Its more like kill guarantee. Second Both Panther and Tiger guns ar given the same kill distaces, but the Panther gun is more poweful than the gun of a Tiger.S o this looks more like a general rule of thumb for all guns.

(taken from the Pantherfibel, Dienstforschrift D655/27)

 

The feline's  gearboxes were not too advanced. The type you are searching for is double differential gearbox, I think. The British used these types, aswell as the French (in their advanced tanks).

The clutch and break system on the T-34 and KV was just outdated compared to that.

If the driver is absolutlely exhausted after a medium length drive in a tank, then there is something wrong with the controls. A tanker should have fight the enemy and not his own tank.

With clutch and break you loose a significant amount of speed when trying to turn  -> need to switch gears more often + hard to operate gearbox -> exhausted driver

 

https://en.wikipedia.org/wiki/Tank_steering_systems

I got some of the general information from there, but this entry seems to have low quality. The Ak-7-200 of the Panther was designed and produced by ZF Freidrichshafen and not by Maybach. The steering mechanism was the "Einradienlenkgetriebe" by MAN and the clutch was "Dreischeiben, trocken, F&S LAG 3/70 H".

 

 

 

 

Share this post


Link to post
Share on other sites
2 hours ago, SchleiferGER said:

Germans include side angles of 30 deg in their maximum kill distances.

Meaning a Kwk 42 can kill a T-34 up to 800m, even when angled. Its more like kill guarantee. Second Both Panther and Tiger guns ar given the same kill distaces, but the Panther gun is more poweful than the gun of a Tiger.S o this looks more like a general rule of thumb for all guns.

(taken from the Pantherfibel, Dienstforschrift D655/27)

...

 

The test of Soviet show that the 88mm not so power as we know when shot T-34 upper hull  front. As my analysis, the impact angle is 52°50′, if the T-34 is real on a 20 degrees downgrade as the data, the impact angle is 43°57′. That's mean, if 800m is a 30 deg in maximum kill distances, the percent of penetration rate is very very low. I also show that, in the Soviet test conditions, if the percent of penetration rate is high, like 90%, and the 50% may be at 1800m or more, the estimated reasult will fit the data which 800m impact angle 60° 50% penetrated. Of course, there are so less datas like this test, it is not easy to get a accurate reasult.

Share this post


Link to post
Share on other sites

I tino the game currently captures the sense ir deadliness of the Tiger when in close-medium ranges (updates to 1000m) and it does not cause immediate kills from far. Often you have to shoot several times (3-6) to kill a T34 at 2000m which Im fine with bUT the tiger seems abnormally too resistant to the t34 at close range (10-100m). Often, 3-5 shoots have to hit the tiger at those distances to effectively destroy it which mat be too much imho.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
Sign in to follow this  

×
×
  • Create New...