Was the Soviet Union preparing to attack Germany?

[Andy Syl]

II think there is a big difference in how we comprehend information. The site you linked to had this: ‘75mm is way too high for L/46 gun, unless someone used HVAP ammo data.It's practical performances in 1941. were about 36mm@500m - so at 500m it could barely penetrate side hull of the Pz-III/IV’.

There is no statement on whether the value is for 90 degrees or 30. Also note that Pz III had 30mm all around and Pz IV B,C,D had 15 and 20mm side armor so second statement is wrong.

Here is another link I found: http://www.battlefront.com/community/sh ... ca&t=57413

Based on this link 35mm/500 is for 30 degrees, a ‘bad’ scenario.

Compare that value with the German tank stats.

By the way I did not give data for Pz II. From ‘Panzertruppen’ i count 793 in Pz units for Barbarossa. From the source I gave earlier : Ausf b -13 front and sides, Ausf c, A,B,C 14.5 front and sides, Ausf D 30 front 14.5 sides , Ausf F 30-35 front 15 sides.

I ask again how are the T-26 and BT unable to deal with German tanks?

Side armor ?
perhaps if the German tank crews are kind enough to turn their flank to the enemy and take no evasive action while the t-26's shot at them . How about penetrating the front while the enemy returns the favor ?

Well, the competent German command considered such a tactic as perfectly adequate. On 26 May 1942, the Command of the Mobile Troops of the Wehrmacht issued a document called "Instruction for Ostfront units regarding the combat against T-34". It said "Our KwK-38 can destroy a T-34 only by firing from the side or the back, from very short distances. It is necessary to shoot in such a manner that the shell would hit the armor perpendicularly".

Great instructions, but there is no suggestion how to bring the KwK gun in such a position so that it could hit the armor of the T-34 at a 90 degrees angle. Unless the German crews had a heavy cargo helicopter on hand, their only option was to drive on a sloped hill (at 40 degrees) and then beg the Soviet crew to come close with their tank and then turn around...

[KDF33]

I am surprised to read that. The KwK 38 could penetrate 46 mm of 30 degree sloped armor at a range of 500 m with the basic APCBC shot. The T-34 Model 1942 had 45 mm of 30 degree sloped armor on the front hull and superstructure, albeit the turret was more heavily armored.

[Omeganian]

Here are figures for the 45mm gun and ammo penetration as tested by Germans.


http://www.panzerworld.net/armourpenetration

[1st Cavalry]

I am surprised to read that. The KwK 38 could penetrate 46 mm of 30 degree sloped armor at a range of 500 m with the basic APCBC shot. The T-34 Model 1942 had 45 mm of 30 degree sloped armor on the front hull and superstructure, albeit the turret was more heavily armored.

the penetration of German guns was calculated at 30 deg from the vertical
the armor plate on the front hull of the t-34 was at 30 deg from the horizontal .

[KDF33]

Oh, that's interesting. What's the 30 degree vertical value of 45 mm of 30 degree horizontal armor?

[1st Cavalry]

Well, the competent German command considered such a tactic as perfectly adequate. On 26 May 1942, the Command of the Mobile Troops of the Wehrmacht issued a document called "Instruction for Ostfront units regarding the combat against T-34". It said "Our KwK-38 can destroy a T-34 only by firing from the side or the back, from very short distances. It is necessary to shoot in such a manner that the shell would hit the armor perpendicularly".

Great instructions, but there is no suggestion how to bring the KwK gun in such a position so that it could hit the armor of the T-34 at a 90 degrees angle. Unless the German crews had a heavy cargo helicopter on hand, their only option was to drive on a sloped hill (at 40 degrees) and then beg the Soviet crew to come close with their tank and then turn around...

the situation in 1942 does not applies to 1941 .
at the start of the war the kv and t-34 represented 5 % of the ussr tank park , the wast majority was vulnerable to German antitank weapons including the 37 mm pak.

[1st Cavalry]

Oh, that's interesting. What's the 30 degree vertical value of 45 mm of 30 degree horizontal armor?

It actually very simple 30 deg from the horizontal = 60 deg from the vertical

at 60 deg from the vertical the armor plate presents a LOS ( line of sight ) double from the thickness of the plate :
20 mm has LOS 40 , 30 mm has LOS 60, 40 mm has LOS 80 , 50mm has LOS 100.

at 30 deg from the vertical the armor plate presents a LOS ( line of sight ) compared to the thickness of the plate :
20 mm has LOS 23, 30 mm has LOS 35, 40 mm has LOS 46 , 50mm has LOS 58.

[paspartoo]

Some comments:

the production of the J variant exceed 1300 examples in 1941 , despite what you might have read on Wikipedia .
It does not need to be impressive , but it does signal the need to replace the vehicles because they are no longer adequate .

From ‘Encyclopedia Of German Tanks Of World War Two’, p65 the Ausf J was used to equip the 2nd and 5th Pz div and an independent pz regt which were sent as reinforcements to Russian in September 1941. The remainder were used to cover the losses of 1941.

Side armor ?
perhaps if the German tank crews are kind enough to turn their flank to the enemy and take no evasive action while the t-26's shot at them . How about penetrating the front while the enemy returns the favor ?

How do you think tanks fought each other? They lined up perfectly in front of each other (possibly on a flat surface?)

Oh, that's interesting. What's the 30 degree vertical value of 45 mm of 30 degree horizontal armor?

It actually very simple 30 deg from the horizontal = 60 deg from the vertical

at 60 deg from the vertical the armor plate presents a LOS ( line of sight ) double from the thickness of the plate :
20 mm has LOS 40 , 30 mm has LOS 60, 40 mm has LOS 80 , 50mm has LOS 100.

at 30 deg from the vertical the armor plate presents a LOS ( line of sight ) compared to the thickness of the plate :
20 mm has LOS 23, 30 mm has LOS 35, 40 mm has LOS 46 , 50mm has LOS 58.

Your numbers are wrong you can’t double armour by sloping it. Effective protection goes up but only up to a point.

[1st Cavalry]

Some comments:

the production of the J variant exceed 1300 examples in 1941 , despite what you might have read on Wikipedia .
It does not need to be impressive , but it does signal the need to replace the vehicles because they are no longer adequate .

From ‘Encyclopedia Of German Tanks Of World War Two’, p65 the Ausf J was used to equip the 2nd and 5th Pz div and an independent pz regt which were sent as reinforcements to Russian in September 1941. The remainder were used to cover the losses of 1941.

Side armor ?
perhaps if the German tank crews are kind enough to turn their flank to the enemy and take no evasive action while the t-26's shot at them . How about penetrating the front while the enemy returns the favor ?

How do you think tanks fought each other? They lined up perfectly in front of each other (possibly on a flat surface?)

Oh, that's interesting. What's the 30 degree vertical value of 45 mm of 30 degree horizontal armor?

It actually very simple 30 deg from the horizontal = 60 deg from the vertical

at 60 deg from the vertical the armor plate presents a LOS ( line of sight ) double from the thickness of the plate :
20 mm has LOS 40 , 30 mm has LOS 60, 40 mm has LOS 80 , 50mm has LOS 100.

at 30 deg from the vertical the armor plate presents a LOS ( line of sight ) compared to the thickness of the plate :
20 mm has LOS 23, 30 mm has LOS 35, 40 mm has LOS 46 , 50mm has LOS 58.

Your numbers are wrong you can’t double armour by sloping it. Effective protection goes up but only up to a point.

A) Panzer III losses in 1941 were 793 compared 976 at the start, that means a lot of replacements .

B )Even if you get on the enemy flank and start shooting , the first thing the other tank is going to do is turn into the attack. A short 90 degree turn and you can no longer hit him in the flank.

C ) Actually trigonometry says exactly that. Do you need a drawing to understand the concept ?

[paspartoo]

A) Panzer III losses in 1941 were 793 compared 976 at the start, that means a lot of replacements .

B )Even if you get on the enemy flank and start shooting , the first thing the other tank is going to do is turn into the attack. A short 90 degree turn and you can no longer hit him in the flank.

C ) Actually trigonometry says exactly that. Do you need a drawing to understand the concept ?

A). The book i referenced gives first appearance of the improved Pz III in September-October. As for replacements you’re free to actually find the relevant stats. Even better would be to find the composition of the attacking Barbarossa force by tank model (I already know how many were Pz II, Pz Iii etc)

B). Sure the correct tactic is to always face the opponent with the toughest part of your armor. Guess what that was not always possible. Most tanks were destroyed by side shots.

C). Mate effective protection isn’t doubled by slope. Have a look around the net, there are some estimates for the T-34 at ~70mm (same number given by Zaloga) and the Panther at ~120mm. Why do you think that is? Shouldn’t it be 90 and 160 if you were right? Keep in mind that this is a big discussion (depends on type of armor, type of projectile, slope etc).

[1st Cavalry]

The Panther front armor was not sloped at 60 deg but 55 deg , LOS = 139.5 mm.
Granted that large caliber shells like the 75 mm and 88 mm bend downward after impacting and do not travel directly along the line of sight . However that is not the case for the 5 cm Kwk 38 or Kwk 39 which we were discussing .

Back to the soviet light tanks issue ,
A) they could not deal with any German tank , just with the older variants which were no longer in production .
B) they retained a window of opportunity against the side armor until the opponent turned the tank to face them
C) they were vulnerable to return fire even to 37mm guns

[Alejandro_]

The Panther front armor was not sloped at 60 deg but 55 deg , LOS = 139.5 mm.

Yes, T-34 glacis armour was sloped by 60°, Panther by 55°. Germans tanks were more limited because front transmission.

[paspartoo]

The Panther front armor was not sloped at 60 deg but 55 deg , LOS = 139.5 mm.
Granted that large caliber shells like the 75 mm and 88 mm bend downward after impacting and do not travel directly along the line of sight . However that is not the case for the 5 cm Kwk 38 or Kwk 39 which we were discussing .

There are countless discussions online on these issues. Check them out.

Back to the soviet light tanks issue ,
A) they could not deal with any German tank , just with the older variants which were no longer in production .

At the start of Barbarossa they could deal with all the German tanks frontally up to 500m with the exception of Pz III H and Pz IV E. From the sides at 500m or even up 1km or more (depending on the model).
Meanwhile T-34 and KV can more than deal with any German tank correct?

B) they retained a window of opportunity against the side armor until the opponent turned the tank to face them

Side armor was weaker for some German vehicles but it was 30mm for Pz III and Pz IV. Again how does that protect them at ranges up to 500m?

C) they were vulnerable to return fire even to 37mm guns

Actually their armor should be in danger even from the Pz II as Jentz gives penetration for 20mm KwK of 20mm/100m and 14/500m at 30 degree angle.

So in conclusion German and Soviet tanks can defeat each other at up 500m with Germans having an advantage at ranges 500-1.000m.
Soviet T-26 and BT are available in much greater numbers. At the same time 1.500 T-34 and KV have absolutely no German equivalent.

[Urmel]

This is probably one of the more useful links for the Panzer III.

http://www.lexikon-der-wehrmacht.de/Waffen/panzer3.htm

Based on this I would surmise that most if not all Panzer III in Russia were either H or J variants. Production numbers in 1940 were low (and already included the H), and out of 381 present on 1 May 1940 155 were lost. 80 - 100 pre-H variants or so were sent to North Africa.

My conclusion would be that the Germans had a very clear technical advantage over the Russian tanks, especially at what were typical combat ranges (about 800m).

[1st Cavalry]

The Panther front armor was not sloped at 60 deg but 55 deg , LOS = 139.5 mm.
Granted that large caliber shells like the 75 mm and 88 mm bend downward after impacting and do not travel directly along the line of sight . However that is not the case for the 5 cm Kwk 38 or Kwk 39 which we were discussing .

There are countless discussions online on these issues. Check them out.

Back to the soviet light tanks issue ,
A) they could not deal with any German tank , just with the older variants which were no longer in production .

At the start of Barbarossa they could deal with all the German tanks frontally up to 500m with the exception of Pz III H and Pz IV E. From the sides at 500m or even up 1km or more (depending on the model).
Meanwhile T-34 and KV can more than deal with any German tank correct?

B) they retained a window of opportunity against the side armor until the opponent turned the tank to face them

Side armor was weaker for some German vehicles but it was 30mm for Pz III and Pz IV. Again how does that protect them at ranges up to 500m?

C) they were vulnerable to return fire even to 37mm guns

Actually their armor should be in danger even from the Pz II as Jentz gives penetration for 20mm KwK of 20mm/100m and 14/500m at 30 degree angle.

So in conclusion German and Soviet tanks can defeat each other at up 500m with Germans having an advantage at ranges 500-1.000m.
Soviet T-26 and BT are available in much greater numbers. At the same time 1.500 T-34 and KV have absolutely no German equivalent.

The numerical superiority of the t-26 and bt din not play a such a important role in 1941 .

In the attack sector of the 2nd panzer gruppe there was only 1 tank division (the 22rd) vs 4 german ,
that one was brushed aside like it was not even there , 100 km to the rear another tank division (30th ) again same story.
the 22nd and 30th tank divisions had some 450-500 T-26 between them irc
Basically all soviet tank forces were committed piecemeal and taken apart one by one , so it does not matter how many tanks you have overall but how many tanks you have where the battle is fought .