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10 minutes ago, Liberator said:

Are you sure that these are non-metal elements?

i think it's aluminium OR non-metall, because there is no point to fasten it with bolts if it's steel + whole structure will be quckly destroyed by incoming hits + weight of that plates

 

CR2 prototype in Bovy have rails even on turret IIRC, serial tanks have this strange plates on turret front and side

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38 minutes ago, Wiedzmin said:

i think it's aluminium OR non-metall, because there is no point to fasten it with bolts if it's steel + whole structure will be quckly destroyed by incoming hits + weight of that plates

 

CR2 prototype in Bovy have rails even on turret IIRC, serial tanks have this strange plates on turret front and side

Some types of steel are also poorly welded to each other. (HH/UHH steel maybe? this is one of the options).

but most likely it really is not steel.

 

 

 

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1 hour ago, Wiedzmin said:

T 225/3237, main problem that there is no detailed info about 5,7(40 and 60 degree cone) and 8(40 and 60 degree cone) inch warheads, what explosive it used, what was the speed of jet etc, thats why real effectivness of all of those "Biscuits" vs real ATGM/RPG not quite clear

Thank you! 

1 hour ago, Wiedzmin said:

you sure that is CR1 hull ?

Pretty sure it is. 

This photo is from the book of CR1 Owners' workshop manual, p29.

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52 minutes ago, Liberator said:

Some types of steel are also poorly welded to each other. (HH/UHH steel maybe? this is one of the options).

but most likely it really is not steel.

g-zXbctKbcY.jpg

 

there was a book about british metallurgy(Military Metallurgy i think), but internal plates of course can be HHS, but i think this is not the case

 

22 minutes ago, Molota_477 said:

Thank you! 

Pretty sure it is. 

This photo is from the book of CR1 Owners' workshop manual, p29.

this book IIRC also writes that CR LFP have "composite armour" ? 

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32 minutes ago, Wiedzmin said:

g-zXbctKbcY.jpg

 

there was a book about british metallurgy(Military Metallurgy i think), but internal plates of course can be HHS, but i think this is not the case

 

this book IIRC also writes that CR LFP have "composite armour" ? 

oh, UTS(ultimate tensile strength) 850 MPa that's good enough.
Is there any other information on the characteristics of this steel?

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@Scav - I know it would be very nice if a "closing date" of a document meant that all sentences and informations of it were updated on the date. Unfortunately reality is less pleasant, as the closing date of a document holds little relevancy to when the contained information was added/updated. In some cases multiple reports have been bundled as one document, resulting in the earlierst parts of the document being reports written (and never modified) multiple months before the closing date listed in the UK National Archives. In other cases the lack of a required signature can result in the closing date being listed as weeks or even months behind the last actual changes to the content of the report. The same can happen with addendums.

There is no gain from keeping to write the same government/military report for a period of multiple months. In most cases, delays between the start and the "closing date" of a document seem to be related to requests of information (i.e. asking other branches/bureaus regarding performance metrics) and sending the report/document to all relevant people.

 

Thus I cannot agree with your argumentation being so much focused on the closing dates of the documents. The fact that a document was closed after the introduction of the Challenger 1 Mk. 1 doesn't ensure that the included information is up-to-date by 1983. Likewise a document started in January 1978 does not "disprove" statements made in a document from April 1978, just because the former document was closed at a later date. It would be a lot easier, if all values, figures, graphics and paragraphs were always updated, but unfortunately this is not what happened (and as far as I am aware, still doesn't happen nowadays).

 

Maybe the Challenger 1 Mk. 1 really had a combat weight of only 59.5 tonnes at the time of its introduction and maybe all of the weight differences can be explained by changes in other components; maybe it did weigh more - I don't know and I do not consider the current sources to be sufficient to draw a definitive conclusion. But based on the available sources, it is clear that the Shir 2 didn't have as potent frontal turret armor as the CR1 and that the requirement for the CR1 was to resist a certain 125 mm APFSDS at ranges up to 1 kilometre.

 

DEFE 24/1369 might mention a protection level of 430 mm vs KE for the turret frontal arc of the MBT 80 (and a new protection level of 405 mm, but increased shaped charge protection), but given the start date of the doucment and statements in GSR 3572, it seems to be pretty clear that this is an older requirement from a time, when the MBT 80 was limited to MLC60 and not the "final protection level upon which the British military has agreed" as you have claimed earlier. GSR 3572 is a more relevant source, as the weight limit was raised, it is newer (by start date), focused on newer threats and makes it clear the 430 mm vs KE was a former requirement, so the chronology is obvious.

 

Now regarding to the section of the Haynes' book: it is unfortunately to vague and ambiguous. First of all, the author mentions that the weight target for the MBT 80 was MLC60, which is true for the earlier concepts with 405-430 mm turret armor. However MLC60 is not 62 metric tons as claimed in the book, but less than 56 metric tons! So it could be a typo and he meant to write MLC70, but then again MLC70 is nearly 64 metric tons, not just 62 metric tons. So did the author mean that the weight of the MBT 80 was 62 metric tons and this places it within MLC70 or did he make a second mistake and mean MLC70 is up to nearly 64 metric tons?

If he meant the latter, the weight would essentially include the MBT 80 configuration with 540 mm equivalent protection against 125 mm APFSDS rounds at the frontal arc of the turret. Then the difference in armor thickness would be irrelevant for your claim, that the MBT 80's thicker armor could be used as proof of the Challenger 1 not reaching 480-500 mm equivalent protection at the frontal arc. However a more likely explanation might be the difference in shape: if the figures are representing armor thickness at normal - as claimed by you (and that honestly seems to be a very reasonable claim), then the difference in turret slope might be enough to fully explain the different turret armor thickness despite both vehicles being meant to reach the same level of protection along the frontal arc of the turret. This is how the late MBT 80 concepts looked:

vjszfgj83oj11.jpg

 

Note the flat turret front. The lack of slope in the vertical plane could be sufficient to explain the difference in armor thickness at normal - the LOS thickness incl. slope could be effectively the same. Also note the hull armor module, which covers the sponsons but has a visible outline.

 

On 5/13/2019 at 6:07 PM, Scav said:

And according to the US, it didn't perform as well as the XM-1, most likely as a result of the skirts (or lack thereof) and hull protection/amount of hits the armour could take. 

I don't think you can deny that the protection levels between hull and turret ended up being different though.

 

The US found that a 86% larger surface area of the XM1 was covered by special armor. They did however not state that the armor of the Leopard 2AV failed to meet the (original/essential) protection requirements such as the frontal resistance to the 127 mm shaped charge warhead. Krapke claims that the Leopard 2AV "met all" protection requirements, though it remains unknown to me, if the partial side protection against RPGs (in the area of ammo storage) was an actual requirement for the XM1 (so wether it was relevant for the Leopard 2AV and Krapke's claim is therefore incorrect) or added at a later point of time.

 

I am not denying that the protection levels between hull and turret are different, I just don't think they are as different as you seem to imply. For the M1 Abrams (or rather XM1 FSED), the only difference in protection between hull and turret was the slight difference in range at which the KE threat could be stopped (800 m distance for the turret, only 1,200 m distance for the hull). The shaped charge protection remained identical (stopping a 127 mm shaped charge warhead along a 50° frontal arc). Why should this be different for the Leopard 2?

The minium LOS of the hull armor along a certain frontal arc is more or less identical to the LOS of the turret at the same angles. So unless the Leopard 2 is somehow different, even though it was designed for and tested against "essentially identical" protection requirements (the only reason why West-Germany and the United States started the cooperative/comparative trials of the Leopard 2AV), there is no reason to assume that the hull was significanlty worse than the turret. Maybe it was the same difference in ranges at which the KE threat could be resisted that were required by the US for the XM1, maybe there was a bigger difference or a smaller difference in range; but protection of hull and turret was likely rather comparable.

 

On 5/13/2019 at 6:07 PM, Scav said:

Also, wasn't DM13 specifically designed to have improved performance against complex targets? 

If so, what would it have comparably better performance to? Some DM13 proto with a monobloc core?

 

DM13 was designed to defeat multiple spaced armor plates better than the previous generation of APFSDS rounds (i.e. XM587 and other prototypes). M111 however is an APFSDS round with a monobloc penetrator and therefore is better against complex targets by itself. 120 mm DM23 also was utilized a monobloc penetrator (which was slightly longer than the two tungsten alloy cores of DM13), because monobloc penetrators are even better than sheated penetrators "designed to have improved performance against complex targets".

 

On 5/13/2019 at 6:07 PM, Scav said:

So, despite carrying the 120 and using (mostly) the same round as the 105, they wouldn't have tested it against the leo 2? 

Seems odd, not that the UK actually had a round that could simulate those estimated 125 rounds either, so not like they could test the armour with it. 

 

The Leopard 1 had a 105 mm L7A3 gun, yet it was never tested (or at least never designed) to resist 105 mm APDS rounds. The early Leopard 2 PT prototypes had either a 105 mm or 120 mm smoothbore gun, yet they were designed to only resist hits from 100 mm APCBC rounds fired from close ranges and 105 mm APDS at 800 m. The Chieftain had a 120 mm L11 rifled gun, yet its armor wasn't resistant to 120 mm L15 APDS rounds nor was it designed to resist those (again focus was put on resisting 100 mm APCBC rounds).

 

The Leopard 2 not being designed to resist 120 mm APFSDS rounds is nothing special. I didn't say it wasn't ever tested against the 120 mm APFSDS rounds, but there hasn't been any evidence publicly available supporting any claims that it would have been tested. If it was tested, then it certainly would only be able resist hits on the turret from longer ranges along a rather narrow arc, based on the Swedish leaks. The requirement for the Leopard 2 was protection against 105 mm APFSDS rounds fired from Rheinmetall's smoothbore gun (or rather to answer your previous nitpicking: the ARGE Leopard 2 told the West-German industry, that they should assume that the armor will be tested against the 105 mm KE/38 round - same result).

 

For the British tests: there are quite a few options to simulate the estimated 125 mm rounds. Sweden used special test projectiles when testing the Leclerc, Leopard 2 Improved and M1A2 Abrams. Sweden also tested the 105 mm smoothbore gun with variable propellant charges in 1976. The Brits could have used the L23/L23A1 prototypes with increased pressure/propellant or they could have created special test projectiles. They also could have tested the armor against their unmodified/existing ammo and then used the leftover/unpenetrated armor thickness to estimate how much overall protection the armor would have offered against a more powerful round.

 

On 5/13/2019 at 6:07 PM, Scav said:

That doesn't explain the lack of textolite, or why they didn't just make the steel plate thicker instead of going more more but thinner plates. 

 

There are lots of possible explanations, at this point I could only speculate, as I have seen no actual Soviet/Russian sources regarding the decisions behind the armor design changes. E.g. the spaced armor still offers somewhat improved protection against shaped charges (see my post about spaced armor earlier in this topic), when multiple thinner spaced plates are used. I.e. the armor could be a trade-off between KE and shaped charge protection, while increasing the maximum weight limit and staying within the armor thickness of already existent solutions. Another explanation might be the type of steel alloys and/or supplier limitations, i.e. the steel plates might not have been available in greater thicknesses with the desired physical characteristics (like e.g. potentially higher hardness). It is also possible that the available space would not have allowed placing a thicker steel plate at optimal stand-off to maximize protection against KE rounds.

 

On 5/13/2019 at 6:07 PM, Scav said:

Would the two layers of explosives not have any effect on this?
I thought that's one of the reasons why they had two layers at different angles.

 

Kontakt-1 sometimes (IIRC not all casettes do, depending on size and location of the tank) contains two reactive sandwiches in order to minimize the dependence on impact angle, i.e. the rather flat way in which Kontakt-1 is sometimes mounted (see T-72B turret) would result in no/little additional protection, when the shaped charge impacts perpendicular on the ERA casette (and thus with the reactive sandwich, if there was only one). As the second sandwich is placed at an angle, the shaped charge jet never can hit both reactive sandwiches perpendicular, meaning Kontakt-1 will always add some protecion against shaped charges even at the least optimal impact angles.

 

On 5/13/2019 at 6:07 PM, Scav said:

You think they left those hollow? 

LOS of the main UFP armour for both is around 630-660mm, with leo 2 going down on the LFP and CR1 also going down starting from the beak til below the numberplate (below that is plain steel). 

 

I think the sponsons are hollow. They are hollow on Leopard 2 and M1 Abrams aswell. The British military has added "cosmetic" steel to the Chieftain Mk. 10 and Challenger 2 aswell (to hide the exact armor layout).

 

The UFP of the Challenger 1 is required to defeat less potent threats (100 mm APCBC rounds & 85 mm shaped charge) and therefore likely a lot lighter than the hull armor of the Leopard 2  - unless the hull protection requirement was downgraded after the American evaluation of 1976, even though the ARGE Leopard 2 wrote in 1977 that hull armor protection should remain unchaged (aside of potentially covering less surface area with the armor module).

 

On 5/13/2019 at 6:07 PM, Scav said:

Also, leopard 2 most likely used HHA and didn't use a cast turret base.... that alone will make it quite a bit more mass efficient (never seen mention of HHA for CR1, but I have seen mentions of aluminium...).

 

As I previously wrote, the Leopard 2's steel structure is likely made from HFX-130 steel (at least there has been a calculation for the cost of such steel plates to make the Leopard 2's turret structure). This is high-grade RHA, not HHS. High-hardness steel is not suitable for structural components of tanks.

 

On 5/13/2019 at 6:07 PM, Scav said:

Why would they downgrade the hull armour from Shir 2 to CR1?

 

To save weight. They also downgraded the armor coverage requirements for the MBT 80 to save weight.

 

On 5/14/2019 at 8:44 AM, Wiedzmin said:

Late requriments for L2 lets say have similar requriments as L3 in terms of KE, 120mm from 1km IIRC(doesn't have doc at the moment), knowing L3 armour array you can propose what L2 array is

 

How? The Leopard 2AV was meant to weight 55.15 metric tons after reconstruction in 1977 (before that it weighed more than 60 metric tons), while armor protection was focused on the MILAN ATGM and the 105 mm KE/38 APFSDS along the frontal arc. Unless the frontal arc requirement was dropped against the 120 mm APFSDS round, I cannot see how the Leopard 2 was supposed to resist the 120 mm DM13 APFSDS at one kilometre range.

 

If you mean the KPz 3 with "L3": at the later stages of the British-German cooperation, it was agreed upon to utilize Chobham armor for the KPz 3.

 

On 5/13/2019 at 12:15 AM, Scav said:

And source for the Vicker's weight is?
It could use newer armour when compared to Challenger 1 which seems to just be a Shir 2 in armour technology. 

 

First of all: do you have any source that the Shir 2's armor was optimized/focused on APDS ammunition only? Even the Chieftain Mk. 5/2 was focused on 115 mm APFSDS ammo.

 

The weight of the Vickers Mk. 7/2 is stated in a document from Forecast International. The same weight value was also published in old editions of Jane's Armour and Artillery. There also is an old British video claimiing a weight of "10 tonnes less than Challenger (1)".

 

 

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On 5/13/2019 at 6:07 PM, Scav said:

What we have is: 

 

  • doc from 1981 saying T-72 tank rounds can only be stopped above 1000m by CR1 turret, same doc specifies said round as penetrating 480mm of RHA at this range
  • UK considering USSR ammo inferior to their own  -> a certain 125 mm APFSDS round was considered inferior to the L23A1 APFSDS, other rounds were considered superior. And they considered 105 mm APDS rounds with tungsten cores superior to 115 mm APFSDS rounds made purely of steel, which is valid against sloped armor based on the poor tip construction of early Soviet APFSDS rounds. 
  • later document (unknown date) specifying turret to protect against 105 and 120mm APDS, 125mm APFSDS such as the quoted Russian round... -> the same document claims that the nearly 10 tonnes lighter Vickers Mk. 7/2 resist 105 mm and 120 mm APFSDS aswell. This seems only you misinterpreting the source - writing "105, 120 and 125 mm APDS and APFSDS rounds" would sound as if there was a 125 mm APDS.
  • Thinner armour than MBT-80 which was required to stop 430mm -> Thinner armor at normal than the MBT 80, which most likely was required to provide protection equal to 480-540 mm steel. Given the different turret shape, the LOS could be identical. MBT 80 requirement for 430 mm protection is older and outdated.
  • same LOS as leo 2 turret -> But 30% higher armor weight while not having 30% higher surface area, so at the same LOS the armor is more densely packed, meaning a higher LOS efficiency. Later Leopard 2 versions also achieve higher protection levels despite staying at the same LOS thickness.
  • higher emphasis on CE protection -> Source?
  • inefficient cast turret base -> But no word on thickness, so it is rather irrelevant.
  • lower weight than Shir 2, tank it's based off and whose armour was 325mm on the glacis and uknown value for turret (not designed against APFSDS). -> Source about the armor not being designed to defeat APFSDS rounds? Given that there is no value for turret armor and we only talk about turret armor, this is rather irrelevant. Also note that the weight of the Shir 2 was listed at 60-62 tonnes, therefore it might be identical to the Challenger 1 (59.5 tonnes = ~60 tonnes).
  •  secondary sources all agreeing CR1 was less armoured than MBT-80 and was "outdated" by  around 1990 -> No issue with that. Still rather irrelevant for this discussion, given the armor protection requirements in GSR 3527.
  • Primary source stating armour was slightly superior to XM-1 -> Which again remains a rather useless statement, as this is very ambiguous.
  • Declassified UK document stating that turret armor of the CR1 was improved over the Shir 2.
  • Protection requirements for the Challenger 1 being 480 mm vs KE at the frontal arc.
  • Much heavier special armor weight.

 

I would agree with you, if there was any sort of source claiming that Challenger 1 failed to meet the protection requirements, but currently, from all sources we, the most relevant/trustworthy ones are suggesting that the Challenger 1 had turret armor equall to 480-500 mm at the frontal arc. You are focusing on old documents of the MBT 80 and Shir 2, even though there are more recent protection requirements for the MBT 80 and there is a document stating that turret armor was changed going from Shir 2 to CR1. "The MBT 80 is meant to be better armored than the CR1" is a rather irrelvant statement, given that there were MBT 80 concepts weighing 55 tonnes, while other weighed 69 tonnes. Which is meant in the source? What is meant with better armored, is this talking about the weak LFP & UFP?

 

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I always find this "protection against 115mm" funny. What kind of 115mm? Penetration was ranging from around 220-240mm (3BM4) to probably more than 400 (3BM36). In 1978 3BM28 entered service, with DU core...

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15 hours ago, heretic88 said:

I always find this "protection against 115mm" funny. What kind of 115mm? Penetration was ranging from around 220-240mm (3BM4) to probably more than 400 (3BM36). In 1978 3BM28 entered service, with DU core...

Afaik the Army made a 115mm DU monobloc round that was used for testing, no idea on the performance but I'm pretty sure someone here does

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13 hours ago, AC GiantDad said:

Afaik the Army made a 115mm DU monobloc round that was used for testing, no idea on the performance but I'm pretty sure someone here does

Yes, that was the 3BM36 "Kamerger". Almost no info available. What is known that is was accepted in service in 1988, and it was part of the same development programme as the 3BM32 "Vant" for 125mm guns.

 

8 hours ago, Molota_477 said:

Britain used 105mm L64 to simulate 115mm KE threat(tungsten cored APFSDS),and 120mm XL23 to simulate 125mm threat ( tungsten cored APFSDS) in early 1980s.

Was the L64 similar to M735 or M111 then?

 

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On 5/18/2019 at 9:50 AM, heretic88 said:

Yes, that was the 3BM36 "Kamerger". Almost no info available. What is known that is was accepted in service in 1988, and it was part of the same development programme as the 3BM32 "Vant" for 125mm guns.

I meant the US Army developed their own as a test round to predict future threats, or it might have been an American 105mm round test fired at expected 115mm velocities

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      Thickness efficiency vs RHA of 1 vs CE, 0.28 vs KE.
      Density-2.2g/cm^3 (approximately 1/3.5 of steel).
      Non-structural, requires confinement (being in a metal box) to work.

                                                                  vi.     Fuel

      Mass efficiency vs RHA of 1.3 vs CE, 1 vs KE.

      Thickness efficiency vs RHA of 0.14 vs CE, 0.1 vs KE.

      Density-0.82g/cm^3.

                                                                vii.     Assorted stowage/systems

      Mass efficiency vs RHA- 1 vs CE, 0.8 vs KE.

                                                               viii.     Spaced armor

      Requires a face of at least 25mm LOS vs CE, and at least 50mm LOS vs KE.

      Reduces penetration by a factor of 1.1 vs CE or 1.05 vs KE for every 10 cm air gap.
      Spaced armor rules only apply after any standoff surplus to the requirements of a reactive cassette.

      Reactive armor materials:

                                                                  ix.     ERA-light

      A sandwich of 3mm/3mm/3mm steel-explodium-steel.
      Requires mounting brackets of approximately 10-30% cassette weight.

      Must be spaced at least 3 sandwich thicknesses away from any other armor elements to allow full functionality. 81% coverage (edge effects).

                                                                   x.     ERA-heavy

      A sandwich of 15mm steel/3mm explodium/9mm steel.
      Requires mounting brackets of approximately 10-30% cassette weight.
      Must be spaced at least 3 sandwich thicknesses away from any other armor elements to allow full functionality. 81% coverage (edge effects).

                                                                  xi.     NERA-light

      A sandwich of 6mm steel/6mm rubber/ 6mm steel.
      Requires mounting brackets of approximately 10-30% cassette weight.
      Must be spaced at least 1 sandwich thickness away from any other armor elements to allow full functionality. 95% coverage.

                                                                 xii.     NERA-heavy

      A sandwich of 30mm steel/6m rubber/18mm steel.
      Requires mounting brackets of approximately 10-30% cassette weight.
      Must be spaced at least 1 sandwich thickness away from any other armor elements to allow full functionality. 95% coverage.

      The details of how to calculate armor effectiveness will be detailed in Appendix 1.

      b.      Firepower

                                                                    i.     2A46 equivalent tech- pressure limits, semi-combustible cases, recoil mechanisms and so on are at an equivalent level to that of the USSR in the year 1960.

                                                                   ii.     Limited APFSDS (L:D 15:1)- Spindle sabots or bourelleted sabots, see for example the Soviet BM-20 100mm APFSDS.

                                                                  iii.     Limited tungsten (no more than 100g per shot)

                                                                  iv.     Californian shaped charge technology- 5 CD penetration for high-pressure resistant HEAT, 6 CD for low pressure/ precision formed HEAT.

                                                                   v.     The general issue GPMG for the People’s Auditory Forces is the PKM. The standard HMG is the DShK.

      c.       Mobility

                                                                    i.     Engines tech level:

      1.      MB 838 (830 HP)

      2.      AVDS-1790-5A (908 HP)

      3.      Kharkov 5TD (600 HP)

                                                                   ii.     Power density should be based on the above engines. Dimensions are available online, pay attention to cooling of 1 and 3 (water cooled).

                                                                  iii.     Power output broadly scales with volume, as does weight. Trying to extract more power from the same size may come at the cost of reliability (and in the case of the 5TD, it isn’t all that reliable in the first place).

                                                                  iv.     There is nothing inherently wrong with opposed piston or 2-stroke engines if done right.

      d.      Electronics

                                                                    i.     LRFs- unavailable

                                                                   ii.     Thermals-unavailable

                                                                  iii.     I^2- limited

      3.      Operational Requirements.

      The requirements are detailed in the appended spreadsheet.

      4.      Submission protocols.

      Submission protocols and methods will be established in a follow-on post, nearer to the relevant time.
       
      Appendix 1- armor calculation
      Appendix 2- operational requirements
       
      Good luck, and may Hubbard guide your way to enlightenment!
    • By Collimatrix
      Shortly after Jeeps_Guns_Tanks started his substantial foray into documenting the development and variants of the M4, I joked on teamspeak with Wargaming's The_Warhawk that the next thing he ought to do was a similar post on the T-72.
       
      Haha.  I joke.  I am funny man.
       
      The production history of the T-72 is enormously complicated.  Tens of thousands were produced; it is probably the fourth most produced tank ever after the T-54/55, T-34 and M4 sherman.
       
      For being such an ubiquitous vehicle, it's frustrating to find information in English-language sources on the T-72.  Part of this is residual bad information from the Cold War era when all NATO had to go on were blurry photos from May Day parades:
       

       
      As with Soviet aircraft, NATO could only assign designations to obviously externally different versions of the vehicle.  However, they were not necessarily aware of internal changes, nor were they aware which changes were post-production modifications and which ones were new factory variants of the vehicle.  The NATO designations do not, therefore, necessarily line up with the Soviet designations.  Between different models of T-72 there are large differences in armor protection and fire control systems.  This is why anyone arguing T-72 vs. X has completely missed the point; you need to specify which variant of T-72.  There are large differences between them!
       
      Another issue, and one which remains contentious to this day, is the relation between the T-64, T-72 and T-80 in the Soviet Army lineup.  This article helps explain the political wrangling which led to the logistically bizarre situation of three very similar tanks being in frontline service simultaneously, but the article is extremely biased as it comes from a high-ranking member of the Ural plant that designed and built the T-72.  Soviet tank experts still disagree on this; read this if you have some popcorn handy.  Talking points from the Kharkov side seem to be that T-64 was a more refined, advanced design and that T-72 was cheap filler, while Ural fans tend to hold that T-64 was an unreliable mechanical prima donna and T-72 a mechanically sound, mass-producible design.
       
      So, if anyone would like to help make sense of this vehicle, feel free to post away.  I am particularly interested in:
       
      -What armor arrays the different T-72 variants use.  Diagrams, dates of introduction, and whether the array is factory-produced or a field upgrade of existing armor are pertinent questions.
       
      -Details of the fire control system.  One of the Kharkov talking points is that for most of the time in service, T-64 had a more advanced fire control system than contemporary T-72 variants.  Is this true?  What were the various fire control systems in the T-64 and T-72, and what were there dates of introduction?  I am particularly curious when Soviet tanks got gun-follows-sight FCS.
       
      -Export variants and variants produced outside the Soviet Union.  How do they stack up?  Exactly what variant(s) of T-72 were the Iraqis using in 1991?

      -WTF is up with the T-72's transmission?  How does it steer and why is its reverse speed so pathetically low?
       
       
    • By Proyas
      Hi guys,
       
      I recently read about upgrade packages to old tanks like the M-60 and T-55, but kept seeing comments from people saying they would still be obsolete. Is this because the M-60 and T-55 are made entirely of steel (and not composite) armor?  
       
      I have this theory that thick steel armor is probably totally obsolete, and is just dead weight in the age of lighter weight composite armor. You can bolt on upgrades to an M-60 or T-55, but you're still hamstrung by the fact that either tank will be carrying around tons of useless steel. Am I right? 
       
      Also, if we wanted to upgrade old tanks like that, wouldn't the best idea be to develop a new turret--with lighter, modern composite armor and better technology inside--and just drop it into the old tanks? The hulls would still be made of heavy steel, but that could be helped a bit by adding applique armor. 
       
      Here are some of the upgrades I read about: 
       
      https://youtu.be/NG89Zh9qQrQ
       
      http://www.army-guide.com/eng/product1907.html
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