History of Soviet tanks

[Jim Warford]

6 hours ago, old_goat said:

... until the requirement of an even more powerful 152mm gun, with unitary cartridges. Resulted in another complete redesign, and in the final failure of the whole project. 

 

Maybe so...but we're talking about continued work (at the time), on 152mm ammo. The 152 was always part of the plan and maybe, just maybe...there are a couple of 152mm-armed Armatas hidden away somewhere. 

[Harkonnen]

--- unitary cartridges. 

 

It had no  unitary cartridges. 

[old_goat]

16 hours ago, Harkonnen said:

It had no  unitary cartridges. 

Yes you are right. For some reason I confused this with unitary.

Still, this was the second 152mm gun in a very short time period, which resulted in another total redesing, and it ensured the failure of the whole project, at least in the soviet times. 

[Peasant]

So, I've been thinking about soviet tanks, and specifically about their serviceability. What was the impact of their extremely compact engine compartment layout? Did they require servicing more often? Less? What was the average time they could function without breakdowns?

Was routine maintenance possible without removal of the engine? Was major servicing only possible after removal of the engine? How did this compare with western tanks of the same era?

I am particularly interested in their heavy tanks (IS series) and what drawbacks their super compact design was subject to?

Edited September 7, 2023 by Peasant

[alejandro_]

1 hour ago, Peasant said:

So, I've been thinking about soviet tanks, and specifically about their serviceability. What was the impact of their extremely compact engine compartment layout? Did they require servicing more often? Less? What was the average time they could function without breakdowns?

Was routine maintenance possible without removal of the engine? Was major servicing only possible after removal of the engine? How did this compare with western tanks of the same era?

I am particularly interested in their heavy tanks (IS series) and what drawbacks their super compact design was subject to?

You mean for WW2 tanks? IS-2 reliability was considered similar to T-34-85 manufactured in the same period. Soviet industry was able to apply a "defect elimination program" and by 1944 issues were fixed. Testing at Chelyabinsk as follows:

In March 1944 production of T-34 at the factory stopped. More IS-2 were needed and mechanical problems needed to be solved. Six tanks from the first batch did not pass the tests. These issues were gradually resolved until August 1944, when no problems were detected.

Every batch was subjected to reliability checks. One tank (any) out of 50 would be taken to complete a 300km course. Once every month another would be selected and perform a 1000km test. Life of the engine was extended to 200 motor hours.

Source is Стальной кулак Сталина. История советского танка 1943-1955

Tankarchives has translated large numbers of Soviet documents, and you can find data on tank reliability:

https://www.tankarchives.ca/2014/06/first-is-2s.html
https://www.tankarchives.ca/2020/04/t-34-85-reliability-1945.html

 

[Peasant]

Thanks. I didn't mean, exclusively WW2 era tanks. IS series continued post war, if we consider that T-10 was originally supposed to be named IS-10.

So the same questions apply to cold war era medium/heavy soviet vehicles. 

[old_goat]

2 hours ago, Peasant said:

So the same questions apply to cold war era medium/heavy soviet vehicles. 

As far as I know, they were generally reliable machines. Soviet post war vehicles were significantly more reliable than ww2 production ones. Even post ww2 variants of wartime models were much more reliable, for example the T-34 didnt have a properly functioning air filter until 1955, when the VTI-3 filters appeared. This immediately boosted the expected life of the engine.
Maintenance on the other hand is a complex subject. General daily maintenance wasnt a big deal, it was more or less an easy task, most filters and lubrication points were accessible without problems.
But, if you needed something more extensive maintenance... God help you. Changing an engine in a T-54/55/62/72 was a world of misery. A full day's job. In this regard, soviet tanks were far inferior to western ones.
The first real improvement was the T-64. Daily maintenance was super easy on the engine compared to the mentioned types. Engine removal was still difficult compared to western tanks, but it took significantly less time than on the previously mentioned types. T-80 was even better. 
One myth needs to be busted though: That soviet tanks were simple, and could be maintained by people with minimal mechanical skills. BS. Soviet tanks were just as complex as western ones, and crews absolutely needed special training for maintenance/repair.

As for average time between breakdowns, I cant say anything specific, but you can find tons of info on Andrei's site. From what I remember, T-55/62 needed the most maintenance. T-64/72 needed significantly less. Also, T-64A and B was on average just as reliable as the T-72, actually, there were periods when the T-64 was MORE reliable than the T-72.
T-80 was a step back in this regard.  

[bojan]

I have a local data somewhere that said (numbers are from memory but are for sure in at least rough ballpark) that per year  of use in training T-34-85 acquired in '60s that passed UKN program required ~30% less maintenance hours than Shermans, while those from 1940s w/o UKN program required about 150% maintenance hours of Sherman.

T-55 required less maintenance than UKN ("good") T-34s, but IIRC not that significant amount (10% or so). T-55s also required less maintenance hour than M47, ~25% less (again from memory, but at least rough ballpark). 

By all local accounts T-72s required less crew maintenance hours than T-55s, through there was only 3 crewmen vs 4 so workload per crewman might have actually increased. I don't have data about "per year" amount of maintenance.

Unfortunately I don't have any data on MTBFs and other parameters, nor detailed breakdown of maintenance hours per year.

Edited September 7, 2023 by bojan

[Peasant]

@old_goat Yes, thank you, this is the kind of information I was looking for.

Since the soviet doctrine saw the tank primarily as an offensive weapon, it follows that it's intended attack location would be known in advance and they could be delivered to it via train or other means other than their own tracks, so their ability to perform long range maneuvers on their own was not as critical to their success.

While one would expect Western MBTs to be expected to react to soviet armour breakthroughs and race towards them from their positions behind the frontline, which can be 50-100km from their intended destination and then retreat back if the situation turn not to their advantage. This call for a vehicle with considerably greater reliability and ability to operate without maintenance stops for prolonged periods of time.

41 minutes ago, old_goat said:

One myth needs to be busted though: That soviet tanks were simple, and could be maintained by people with minimal mechanical skills. BS. Soviet tanks were just as complex as western ones, and crews absolutely needed special training for maintenance/repair.

Well, if we're talking about Cold war era, then yes, but in the '20s and '30s, even after Stalin's 5-year plans, the USSR was still mostly an agricultural nation. Among the adult male population (potential tank crews) there were very few people who worked with trucks/cars, on a permanent basis, and knew how to drive and service them.

[alejandro_]

1 hour ago, bojan said:

By all local accounts T-72s required less crew maintenance hours than T-55s, through there was only 3 crewmen vs 4 so workload per crewman might have actually increased. I don't have data about "per year" amount of maintenance.

Stefan Kotsch used both types and he has a similar opinion.
 

2 hours ago, old_goat said:

As for average time between breakdowns, I cant say anything specific, but you can find tons of info on Andrei's site. From what I remember, T-55/62 needed the most maintenance. T-64/72 needed significantly less. Also, T-64A and B was on average just as reliable as the T-72, actually, there were periods when the T-64 was MORE reliable than the T-72.
T-80 was a step back in this regard.  

USSR carried out a comparison of T-62/64/72/80 in 1976, and T-80 was the tank that needed less maintenance in terms of hours per 1,000 km.

T-80 tanks - 8.16 hours
T-64A tanks - 11.06 hours
T-72 tanks - 13.03 hours
T-62 tanks - 22.12 hours

https://warspot.ru/18042-samyy-prozhorlivyy-tank-sovetskogo-soyuza

Of course, the results can vary depending on the year and batch, but T-80s were reliable. Turbines are simple to operate if you got enough resources.

4 hours ago, Peasant said:

Thanks. I didn't mean, exclusively WW2 era tanks. IS series continued post war, if we consider that T-10 was originally supposed to be named IS-10.

So the same questions apply to cold war era medium/heavy soviet vehicles. 

Regarding T-10 and IS-3, it is more difficult to say because there are less data. IS-3 had a number of issues, but so did other tanks produced during the war. After UKN program it seems to have served well. An IS-3 tank regiment commander stated that in 1956 the tanks were pushed hard and had no major issues. T-10 was a conservative design that followed IS-4 failure. I have not come across any comments about it being unreliable.

[old_goat]

2 hours ago, alejandro_ said:

Of course, the results can vary depending on the year and batch, but T-80s were reliable. Turbines are simple to operate if you got enough resources.

Indeed, results varied, but overall, statistics say that T-80 had significantly more problems than T-64/72

http://btvt.info/5library/nadeznost_1987_64-72-80.files/image004.jpg

2 hours ago, alejandro_ said:

Regarding T-10 and IS-3, it is more difficult to say because there are less data. IS-3 had a number of issues, but so did other tanks produced during the war.

There is some data that may be useful to guesstimate the overall reliability of these tanks. For example, V12-5 engines had very short guaranteed service lives, only 200 hours. In the T-10M, the upgraded V12-6 reached 300, but that was still less than the V55 from T-55/62 tanks. (350 hours)

The IS-3, well, I think that tank was a failure. Yes it had great firepower, excellent armor, but it was a big step back in the "soft factors" compared to IS-2. It was especially bad in ergonomics and visibility. I think there was a story here about the IS-3 tests in Poland. The tank was considered inferior to IS-2 in every way except armor protection, and was almost immediately rejected. Also, the IS-3 was plagued with severe hull cracking issues, which was only partially solved post ww2, after several unsuccessful attempts. 

The significance of the IS-3 was in my opinion, that it served the development base for the T-10, which was a successful design after all. (at least I didnt read anything negative about it)

[urbanoid]

The Egyptians weren't particularly impressed with IS-3s in their service, neither was Israel that captured some and didn't make any use of them, unlike with T-54/55/62s.

[bojan]

Israelis captured relatively few operational IS-3s and they had no doctrinal place for those. Their single engagement with IS-3s was far from one sided.

[Harkonnen]

In his interview yesterday (https://www.youtube.com/watch?v=SLUrrmNrZxk&t=1s), the historian of the UWZ and author of many books that some researchers have the misfortune to use, said that "A pathological liar differs from a normal person in that he lies without reason. For no reason at all. And we, as a rule, have some reasons for that..."
Also, this falsifier of history refused to acknowledge photos of documents (http://btvt.info/4ourarticles/morozov_2023_T_54.htm) that refute his lying books and interviews.

[Peasant]

@Harkonnen https://politicaldictionary.com/words/big-lie/

Quote

A “big lie” is an extreme distortion of the truth, used for the purpose of spreading propaganda. It is often somewhat outrageous.

In theory, people will more easily believe a big lie than a smaller one, because most people assume that there is evidence to support any statement of great magnitude.

The term was coined by Adolph Hitler in his autobiography, Mein Kampf.

Hitler wrote that “the great masses of the people… will more easily fall victim to a big lie than to a small one.”

He also claimed that if propagandists repeated a lie often enough, people would come to accept it.

Eventually, that lie would inform people’s thinking on other related issues.

Hitler did not say that he, himself, was spreading a big lie. Rather, he accused European Jews of spreading “falsehoods and calumny” about Germany’s role in World War I.

However, Hitler’s propaganda minister, Joseph Goebbels, is closely associated with the technique as they implemented the “Final Solution.”

....(more)

There are no "independent experts" in russia today. The goverment has no interest in educating people about the truth and facts. Everything shown and said on TV is meticulously crafted to present a version of reality they want people to see.

Quote

"Who controls the past controls the future. Who controls the present controls the past."  (c)G.Orwell "1984"

 

[alejandro_]

On 9/7/2023 at 7:20 PM, old_goat said:

Indeed, results varied, but overall, statistics say that T-80 had significantly more problems than T-64/72

http://btvt.info/5library/nadeznost_1987_64-72-80.files/image004.jpg

There is some data that may be useful to guesstimate the overall reliability of these tanks. For example, V12-5 engines had very short guaranteed service lives, only 200 hours. In the T-10M, the upgraded V12-6 reached 300, but that was still less than the V55 from T-55/62 tanks. (350 hours)

The problem with that data is that it is presented in a vacuum. Did the vehicles have the same mileage? Where did they operate? Turbine T-80s have higher resource than T-64/72 when it comes to overhauls.
 

On 9/7/2023 at 7:20 PM, old_goat said:

The IS-3, well, I think that tank was a failure. Yes it had great firepower, excellent armor, but it was a big step back in the "soft factors" compared to IS-2. It was especially bad in ergonomics and visibility. I think there was a story here about the IS-3 tests in Poland. The tank was considered inferior to IS-2 in every way except armor protection, and was almost immediately rejected. Also, the IS-3 was plagued with severe hull cracking issues, which was only partially solved post ww2, after several unsuccessful attempts. 

The significance of the IS-3 was in my opinion, that it served the development base for the T-10, which was a successful design after all. (at least I didnt read anything negative about it)

If IS-3 would have been fielded during the war these issues would not have been such a big issue. When the prototype was tested the reliability was similar to that of IS-2. Regarding engine life, T-64 (Objekt 432) engine was supposed to have a warranty for 300 hours, but in practice engine worke for 200 hours. By 1971 it reached 400 hours (in Objekt 434 - T-64A).
 

22 hours ago, bojan said:

Israelis captured relatively few operational IS-3s and they had no doctrinal place for those. Their single engagement with IS-3s was far from one sided.

 It was a tougher opponent that other opponents. In the late 1940s Israel was keen on acquiring Stalin tanks and there is mention to them in a document. By 1967 it was a thing of the past.

[Harkonnen]

1 hour ago, alejandro_ said:

The problem with that data is that it is presented in a vacuum. Did the vehicles have the same mileage? Where did they operate? Turbine T-80s have higher resource than T-64/72 when it comes to overhauls.

So you suppose Soviet army tеsted T-64? 72 and 80 with different mileage to compare their reliability? They tested them in different areas? It seems the word logic is foreign to some modern people, they can't assume that it was different before. Or is it just such a ridiculous attempt to not accept a reliable source while remaining in the realm of myth. 

Edited September 8, 2023 by Harkonnen

[Harkonnen]

1 hour ago, Peasant said:

@Harkonnen https://politicaldictionary.com/words/big-lie/

There are no "independent experts" in russia today. The goverment has no interest in educating people about the truth and facts. Everything shown and said on TV is meticulously crafted to present a version of reality they want people to see.

 

This started 2 decades before today's events and is an echo of UVZ's policy in the USSR of the 1970s. It has nothing to do with modern Russia.  This is just another warning - books published by UVZ are useful only as a source of photos, not as a historical source. 

[Harkonnen]

On 9/7/2023 at 6:55 PM, alejandro_ said:

but T-80s were reliable. Turbines are simple to operate if you got enough resources.

Statistics say it was 4-6 times less relieble than T-64-72.

[old_goat]

1 hour ago, alejandro_ said:

The problem with that data is that it is presented in a vacuum. Did the vehicles have the same mileage?

Well, this was answered above. Anyway, we also have data about the suspension components, and again, T-80 has more defects than both T-64 and T-72.
As for the guaranteed engine life, no the GTD-1000 series never exceeded the diesels. It had the same 500 hour warranty period as the V46 and 5TDF. It was the GTD-1250 that finally had higher warranty periods.
http://btvt.info/3attackdefensemobility/niid_1978.htm

1 hour ago, alejandro_ said:

If IS-3 would have been fielded during the war these issues would not have been such a big issue.

These were very serious problems. IS-3 was an ergonomic nightmare compared to IS-2, it definitely leads to less performance due to quick crew exhaustion. Also, the commander had atrocious visibility from his single Mk.4 periscope (pre war level!), its far inferior to IS-2. This again leads to worse performance.
Hull and engine mount cracking was severe in the first years of its service, and was never entirely eliminated. The tanks were used very sparingly during training, but despite this, there were periods when most tanks were unavailable. If I remember correctly, there were at least 3 attempts to fix this, and only the last was partially successful in the 50s.
Even worse, it was soon discovered that the turret welds also began to crack. IS-3 was simply an extremely poorly designed tank, its whole service life was constantly plagued with mechanical problems. A true paper tiger, no surprise that Poland rated the IS-2 a better tank.
Read here (several pages):
http://ser-sarajkin.narod2.ru/ALL_OUT/TiVOut13/SuSchwPz/SuSchwPz004.htm

1 hour ago, alejandro_ said:

By 1971 it reached 400 hours (in Objekt 434 - T-64A).
 

Yes, and a little later, it was extended to 500 hours, which was the same as the V46. After the initial problems were eliminated, the 5TDF became a good, reliable engine.

[alejandro_]

39 minutes ago, Harkonnen said:

So you suppose Soviet army tеsted T-64? 72 and 80 with different mileage to compare their reliability? They tested them in different areas? It seems the word logic is foreign to some modern people, they can't assume that it was different before. Or is it just such a ridiculous attempt to not accept a reliable source while remaining in the realm of myth. 

When they were tested in 1976 the T-80 needed less maintenance than T-62/64/72, and no comment is made about this failure rate. Maybe it is a conspiracy.

24 minutes ago, old_goat said:

Well, this was answered above. Anyway, we also have data about the suspension components, and again, T-80 has more defects than both T-64 and T-72.
As for the guaranteed engine life, no the GTD-1000 series never exceeded the diesels. It had the same 500 hour warranty period as the V46 and 5TDF. It was the GTD-1250 that finally had higher warranty periods.
http://btvt.info/3attackdefensemobility/niid_1978.htm

According to Ukrainian Armed Forces, a new T-80 goes through a capital repair at 14,000 km, warranty is 6,000 km. For T-64 these values are 11,000 and 5,000. T-72 14,000 and 5,000 km.

Pakistan was offered a T-80UD variant with T-64 suspension/running gear, which was rejected. I guess it was another Russian conspiracy. 
 

Quote

Even worse, it was soon discovered that the turret welds also began to crack. IS-3 was simply an extremely poorly designed tank, its whole service life was constantly plagued with mechanical problems. A true paper tiger, no surprise that Poland rated the IS-2 a better tank.
Read here (several pages):
http://ser-sarajkin.narod2.ru/ALL_OUT/TiVOut13/SuSchwPz/SuSchwPz004.htm

Link does not say anything about Poland or lack of visibilty in commander's position. IS-3 had more than twice front turret armour, and better hull protection. Countries might have rejected because they had not use for it, but not because IS-2 -which also went through a UKN program- was superior
 

Quote

Yes, and a little later, it was extended to 500 hours, which was the same as the V46. After the initial problems were eliminated, the 5TDF became a good, reliable engine.

 

Sure, but I don't get why 350 hours out of an T-10 engine is a drama and taking years to get the T-64 engine from  300 to 400/500 is not an issue.

Edited September 8, 2023 by alejandro_

[old_goat]

18 hours ago, alejandro_ said:

According to Ukrainian Armed Forces, a new T-80 goes through a capital repair at 14,000 km, warranty is 6,000 km. For T-64 these values are 11,000 and 5,000. T-72 14,000 and 5,000 km.

What T-80? Ukraine and "new" T-80 probably means T-80UD. Which is an entirely different beast. On the hull, the suspension is probably the only common thing between the UD and the B.

18 hours ago, alejandro_ said:

Pakistan was offered a T-80UD variant with T-64 suspension/running gear, which was rejected. I guess it was another Russian conspiracy. 

It was never seriously offered. Ukrainians mainly tested the possibility of using T-64 running gear on T-80 chassis. It wasnt a big success, but it wasnt a failure either. The suspension easily dealt with the increased weight, the problem was that at near top speed, bearings overheated, and it was already known from the T-64.

18 hours ago, alejandro_ said:

Link does not say anything about Poland or lack of visibilty in commander's position. IS-3 had more than twice front turret armour, and better hull protection.

The polish story was told by one of TN members here, quite a while ago. 
As for the lack of visibility, yes the article doesnt say that, because it does not need to. It is totally obvious. If you dont believe it, just check out, for example the A.10 Cruiser video of the Chieftains hatch. Exact same setup. Single Mk.4 periscope. Nothing else. What does he say? "Total lack of vision"...

18 hours ago, alejandro_ said:

 

Sure, but I don't get why 350 hours out of an T-10 engine is a drama and taking years to get the T-64 engine from  300 to 400/500 is not an issue.

I dont think there was any drama about it. I just mentioned that the short engine life of the T-10 may be an indicator of increased maintenance needs. And it doesnt mean that the T-10 was a bad or unreliable tank, I never said that. (in fact, I think the T-10M was an excellent tank in its time, the designers corrected every flaw of the IS-3)

[Harkonnen]

On 9/9/2023 at 12:42 AM, alejandro_ said:

According to Ukrainian Armed Forces, a new T-80 goes through a capital repair at 14,000 km, warranty is 6,000 km. For T-64 these values are 11,000 and 5,000. T-72 14,000 and 5,000 km.

It's about the breakdown rate/1000 km which means reliability but not capital repair milage.

[alejandro_]

On 9/9/2023 at 5:04 PM, old_goat said:

 Ukraine and "new" T-80 probably means T-80UD. Which is an entirely different beast. On the hull, the suspension is probably the only common thing between the UD and the B.

No, value for T-80UD is 14,000 km for capital repair and 5,000 warranty. The later value is 6,000 km for T-84, Oplot and derivates, finally matching turbine T-80s.
 

On 9/9/2023 at 5:04 PM, old_goat said:

It was never seriously offered. Ukrainians mainly tested the possibility of using T-64 running gear on T-80 chassis. It wasnt a big success, but it wasnt a failure either. The suspension easily dealt with the increased weight, the problem was that at near top speed, bearings overheated, and it was already known from the T-64.

It's a bit wired to offer something "but no seriously". Configuration was offered and rejected because customer preferred T-80. Strange choice if the tank is 4-6 times less reliable than T-64/72. 

On 9/9/2023 at 5:04 PM, old_goat said:

The polish story was told by one of TN members here, quite a while ago. 
As for the lack of visibility, yes the article doesnt say that, because it does not need to. It is totally obvious. If you dont believe it, just check out, for example the A.10 Cruiser video of the Chieftains hatch. Exact same setup. Single Mk.4 periscope. Nothing else. What does he say? "Total lack of vision"...

I have read about IS-3 for a number of years, also been a member of this grate site since 2005,  and I have never come across this information. In Polish/Russian sources you will get a couple of lines or a paragraph explaining it.

Now, some IS-3 documentation is available in English. Regarding approval for production:

- The IS-3 tank presented by Kirov Factory passed the 500 km long proving grounds trials. It did not pass the 1000 km warranty trial due to the fan breaking at 810 km.
- The performance characteristics and reliability of mechanisms and assemblies of the IS-3 tank is equivalent to that of the mass production IS-122 tank.

https://www.tankarchives.ca/2016/05/is-3-green-light.html

There is even a description of the visibility, but no comment on the deterioration of the visibility when compared to IS-2 (I have not come across this in the documents published at the website).

https://www.tankarchives.ca/2016/05/is-3-visibility.html

[Interlinked]

The visibility of IS-3 and IS-4 was an example of Soviet design orthodoxy at the time. They (GABTU) considered that the optimal solution for all-round vision would be a single MK-4 gundlach periscope without a cupola (therefore no weak point). The cupolas on tanks like T-34 and IS-2 were there to compensate for the turret ring not being wide enough to completely fit the commander within it. Officially, the vision slits were considered backups, in case the MK-4 failed.

On new developments like these late war heavies and the T-44 (which got its low profile cupola from the IS-6, which got its cupola from the T-43), the design policy was to have one MK-4. When working with completely new hulls and turrets, it was possible to make sure the commander was seated completely inside the turret ring.