Main Battle Tanks and Armour Technology

[Damian]

US Army plans to have M1 series up to 2050, at this time last M1's in service will be something around 57-70 years old, depending on when they were manufactured.

 

[asianobserve]

US Army plans to have M1 series up to 2050, at this time last M1's in service will be something around 57-70 years old, depending on when they were manufactured.

That's nothing compared to this:http://www.gizmag.com/b52-upgrade/20098/ (Upgrades to extend B-52 Bomber's lifespan until 2044), which means that USAF B-52s will be around 80 years old by the end of their service lives.

 

[SPIEZ]

Well it's between 30 and 40 years, even without replaced PP. Usally tanks have long-life.

In that how come the Israeli's use the T55 tanks, manufactured in 1950's, converted to heavy APC even now?

 

[p2prada]

I am quite confused with Indian 125 mm FSAPDS ammo:
This image here says Mk. 1 has a L/D-ratio of 14, whereas Mk. 2 has a L/D-ratio of 20.
But here Mk. 1 is claimed to have a L/D-ratio of 20. Also an older 125 mm APFSDS exists. So could it be that Mk. 1 has been mistaken for the older APFSDS in the first image, or does they use different designations? Note also that the first image shows the two APFSDS on OFB.gov.in or Mk. 2 looks like the older APFSDS.
Jane's wrote some years ago (1995) that India has been developing a modular APFSDS design, which could be scaled and used in 100, 105, 120 and 125 mm caliber (with a penetration of 500 mm at 2,000 m range).
Also Jane's reported that the Indian Mk. 1 ammunition is a licence built version of the M711 (CL 3254). OFB.gov.in's value for L/D-ratio (~20) matches Jane's. This would mean Mk. 1 = CL 3254 and Mk. 2 = CL3579 (which is also noted on IMI's homepage).
Jane's, the Indian Ordnance Factories and the first-linked-to image all give different muzzle velocities for the rounds.

Yeah. The designations are messed up.

The Indian designation for Russian 3BM-42 is AMK-339 and the Indian round is AMK-340A. There was another Russian round in service called the AMK-338.

The 340A was basically a CL3254 with Russian propellant. It was a failure and thousands were destroyed because the shells would freeze in the barrel after being exposed to the sun. I guess it leaks.

Current status of the shell is unknown but we know that new orders were being negotiated for the 3BM-42 from Russia. So, there could be a redesign or a new project. I guess they are running in parallel with new shells for Arjun too.

We don't know if the Israeli Mk2 is in service in India. The problem is most of our news about the T-90s and T-72s are from early and mid 2000s. We don't have latest news.

 

[militarysta]

Methos

Im looking any infos about autoloader from NKPz - have You smth.?

 

[methos]

Sorry, I don't have any relevant information. At the time the project was canceled, not a single prototype was made. If RUAG had finished at this the development of their 120 mm smootbore gun, which would have been required prior developing an autoloader is not know to me. Rolf Hilmes' Kampfpanzer Entwicklungen der Nachkriegszeit has a very short extract about the NKpz, but nothinfg specifically about the autoloader. Stefan Kotsch's website features a very short article about the autoloader - he writes that magazines of the autoloader can carry 22 rounds and were located in the hull. Afaik Hilmes wrote that one of the magazines is standing and the other is located horizontally on the ground. How these magazines were switched when one was empty... no idea.

 

[militarysta]

(...)

Thanx I was asking, for that reson:
(under translation to english; taken from Andriej-bt bog)

1-driver; 2-gunner, 3 -TK, 4 -power pack, 5- fuel, 6 -autoloader, 7 - ammo store

First table name: "probability of destruction the specific componentof of at tank"
..........................system design (option)
element:
TK
gunner
driver
power-pack
ammo store
autoloader

Second table name: "warfare simulation results"
..........................system design (option)
probability:
Pom
Pn
Pq

Pom - probability to save the firepower
Pn - probability to save mobility
Pq - probability to save the possibility of fighting


Design No.III (from NKPz) has been mathematically modeled as the best, becouse tank in this design have three times better survival probability in combat than tank whit classical design.

Of course mathematical modeling is not everything, so Ob.195, EGS(NGP), TTB, etc have design whit crew in armored caplsule in front of tank, next autoloader and turret whithout crew inside and after that power-pack (design VIII in this article).

 

[militarysta]

Well, I would like to present 3 of my article about 125 and 120mm APFSDS-T ammo in Polish Army:

Part I
Dwa dramaty – czyli o amunicji czoÅ‚gowej słów kilka, część 1 « Gdzie zaczyna siÄ™ wojsko"¦

Part II
Dwa dramaty – czyli o amunicji czoÅ‚gowej słów kilka, część 2 « Gdzie zaczyna siÄ™ wojsko"¦

Part III
Dwa dramaty – czyli o amunicji czoÅ‚gowej słów kilka, część 3 « Gdzie zaczyna siÄ™ wojsko"¦

Of course they are in polish, but all ammo dates, estimates about armour protections, drawings, etc doesn't need understanding of the Polish language . Of course google translator can "catch" and more or less translate this


BTW:
anticipating questions - Methos - 470mm RHA for DM33A1 for 2000m and 560mm RHA for DM43 for 2000m are taken from WITU pdfs. This values are propably corret and difrences between that 470 and 560 and western (janes, colins, etc) dates is caused by diffrent metodology of counting guaranteed perforation. Polish WITU just using Russian/Soviet norm which are much stricter then westerns ones.
Of course I event don't mind abour difrences between perforation guaranteed (WITU) and achievable...

 

[methos]

I still doubt that WITU has values for guaranteed perforation of all Western APFSDS. 120 mm DM 43A1 is longer and faster than Wariant IV, 3BM-42 or 3BM-42M. The diameter is not greater than that of Wariant IV or 3BM-42M. I believe that the 560 mm at 2 km come from here, which stands in contradiction to what is written here.

Jane's DM33/43

Penetration performance has been reported as 560 mm of Rolled Homogeneous Armour (RHA) at 2,000 m.

Jane's KEW

No armour-penetration details have been released, although the DM43A1 round is stated to be able to "defeat any currently fielded armour targets".

BTW: DM43 was not adopted because of delays during development - when it was ready both DM53 and the L/55 were in development. It was however adopted as KEW-A1 by Egypt, Saudi Aarabia and Kuwait and as OFL120 F1 by France.
Afaik it was qualified in Germany somewhere arround 1996 and in 2000 in the U.S., while DM53 was qualified in Germany prior it entered service with the Swiss army 1999.

 

[militarysta]

I still doubt that WITU has values for guaranteed perforation of all Western APFSDS.

Well in WITU they tested DM33A1, DM43 (on its components is based "new-old" polish APFSDS) and russian BM family (including BM42) so propably this dates can be correct.
About DM43A1 - well, if "guaranteed" perforation is ~560mm that achievable should be slighty more then 600-620mm RHA for 2000m.
[/QUOTE]

BTW: I found on what idea had worked NKPz autoloader. It was very very clever designe! Im in little shock

 

[methos]

There are many things people believe/trust in.
One example is harkonnen/andrei_bt who seems to believe that the Ukraine makes equipment superior to anyone elses', another one is Armand who seems to believe that France makes equipment superior to anyone elses'; another example are large numbers of people here in this forum believing that China and Pakistan can't make any good weapons or vehicles.
But the normal/average person should believe in one thing at least: Physics.
I'm not an expert in Physics nor am I an expert in penetrator design. I also have some doubts that the most common estimates based on Anderson's or Odermatt's equoations are valid (because the difference between perpendicular and slanted impact seems unreasonable high). But a part from the basics I know is the basics behind armour penetration including the basics of APFSDS penetration.
The DM43A1 round has about the same diameter than the Wariant IV, but has probably* a longer penetrator and a higher muzzle velocity. That means there is more energy per area and the penetrator has more time until it is fully eroded.
So there are only three ways how Wariant IV can reach the same armour penetration:
1.) There exist some serious design flaws in German APFSDS
2.) WITU created some masterpiece of alloy increasing the penetration power by more than 20%
3.) 1 + 2 together

So unless you believe one of the three points it is impossible to Wariant IV to perform as good as DM43A1.
And this is not only the case with WITU's Wariant IV, but also with some other rounds. I.e. some people on TankNet claimed that M322 can penetrate 650 mm at 2,000 m while DM43A1 should penetrate only 590 mm at the same range... given the informations IMI's website: Impossible.

_________________
*Amongst others there is a patent from Rheinmetall to create an APFSDS with even the tip made of WHA, which is said to increase performance against sloped targets. Old Rheinmetall homepage claimed that DM43 performs better against highly sloped targets.

 

[Damian]

Methos, but we should carefully consider that whole truth is not known to us, and some design solutions are probably still classified.

 

[methos]

Yes, but it is allways the same - we don't know any design solution of a modern (post-1980) APFSDS - except some Soviet made one (and even there are problems with the penetrating and ballistic caps).

Jane's once reported the value 560 mm at 2,000m a long time ago, and following this everybody claims that DM43 is some sort of failure. Still it was adopted by a number of countries. Jane's has also withdrawn their earlier statement about 120 mm DM43A1 in their more up-to-date KEW article.
The following has been written on the Rheinmetall homepage some time ago, but was deleted after they changed their design and contents:

Die 120 mm APFSDS-T Patrone ist eine Weiterentwicklung der KE-Patrone DM 33 A1. Die Patrone kann mit den Rheinmetall-Glattrohrwaffenanlagen L44 und L55 verschossen werden. Durch die Neuentwicklung des Penetrators, des Treibkäfigs und des Antriebes konnte die Munition erheblich in der Leistung gesteigert werden.

Die Patrone wird für höchste Leistungen bei sehr flachen Winkeln gegen geneigte Panzerungen optimiert und hat auch gute Wirkung gegen reaktive Ziele. Zu dieser hohen Wirkleistung trägt wesentlich der neue Antrieb bei, so dass gegenüber der DM 33 A1 ein Vo-Sprung von fast 100m/s erreicht wird.

Der Aufbau der Patrone entspricht dem der KE-Patrone DM33 A1.

This means roughly:

The 120 mm APFSDS round is a further development of the KE round DM 33 A1. The round can be fired by the Rheinmetall smoothbore guns L44 and L55. Due to new developing the penetrator, the sabot and the propellant the ammunition was significantly enhanced in performance.

The round is optimized for highest performance at very shallow angles against sloped armour and also has good performance against reactive targets. To this high performance the new propellant accounts considerably, so that a V0-jump from nearly 100 m/s could be achieved.

The structure of the catridge is about the same as the one of the KE round DM 33 A1.

According to General Dynamics Ordnance And Tactical Systems DM43A1 is better than M829 at all ranges, with the latter one being credited with 540 mm at 2,000 m by Jane's. The superior performance of DM43 increases with ranges (due to lower vdrop probably)... if the difference at 2,000 m is only 20 mm, how much would DM43 then penetrate at 0 m? 5 mm more? This would probably be not enough to claim that DM43A1 is superior at all ranges.

 

[militarysta]

OK, but Methos - maybe all dates in 2000.' were overestimated? I really have problem to event thinkt that guys from WITU make some kind of fake about DM-33A1 and DM43 - for what? What is reson of underestimation those rounds? I see no reason - in Poland we produce "new" APFSDS 120mm in cooperation whit Germany, so german's industry have some money for propelants charge, rods, etc. Only, very very small hypothesis can by some kind of OPSPEC build on idea: "we pretend that we have weaker APFSDS then it really is" But it haven't sense for me.
I suppose the difference is caused by difference between guaranteed and achievable pernetratio for both round - is the only logical explanation for me.
In that case DM-33A1 for WITU have 470mm RHA, but for rest it have more then 510-520mm RHA, and "new" DM-43A1 for WITU have 560mm RHA but for rest it have about 620mm RHA. It's full entirely possible becouse the difference between this two kinds of penetration is really big. For russian ronds made for tungsten its about ~50mm perforation, for rods DU made it's about 50-60mm. So maybe there is no discrepancies between the datas?

 

[methos]

WITU says DM 33 penetrates 470 mm at 2,000 m. BM-42 Mango should penetrated 450 mm at 2,000 m. Let's take a look at it,
The projectile of BM-42 Mango 56 cm long, DM 33 projectile is 64 cm long. -> DM 33 is more potent.
BM-42 Mango penetrator is 41 cm long, the penetrator of DM 33 is 57 cm long -> DM 33 is more potent.
The diameter of the BM-42 projectile is about 30 mm average, with the middle section being about 36 mm thick. The diameter of the DM 33 projectile is about 28 mm. -> DM 33 is more potent.
BM-42 is using a two-part penetrator in steel body, DM 33 is a monobloc round. -> DM 33 is more potent in penetrating both homogeneous and complex targets.
The muzzle velocity of BM-42 is about 50 m/s higher, but the fins and the overall diameter are larger causing more friction. The loss of velocity during flight is therefore higher on BM-42, which means that it is having about the same impact velocity somewhere at 1,000 - 2,000 m range.
This would mean that a penetrator being more than 10 cm longer and a smaller diameter will increase penetration by only 20 mm? Yes, for sure..

I really have problem to event thinkt that guys from WITU make some kind of fake about DM-33A1 and DM43 - for what? What is reson of underestimation those rounds? I see no reason - in Poland we produce "new" APFSDS 120mm in cooperation whit Germany, so german's industry have some money for propelants charge, rods, etc. Only, very very small hypothesis can by some kind of OPSPEC build on idea: "we pretend that we have weaker APFSDS then it really is" But it haven't sense for me.

I must admitt that I don't have even a clue why WITU is having some sort of archieve about penetration values. That DM 33 is underestimated, might lie in Polish tests or in the fact that it is politically better to say that the new homemade APFSDS penetrating 500 mm at 2,000 m is superior in performance than the old DM 33 - while costing more because of R&D.
When Poland recieved their first Leopard 2A4s Switzerland already used DM 53 with their Pz 87... so why exactly should they have tested DM 43? DM 53 is already available at this time. I think it is pretty suspicious that their value matches with the one claimed by Jane's - Jane's decided to withdraw this value in their KEW article, so it seems that the Jane's authors somehow do not believe in the 560 mm at 2,000 m anymore.

In that case DM-33A1 for WITU have 470mm RHA, but for rest it have more then 510-520mm RHA, and "new" DM-43A1 for WITU have 560mm RHA but for rest it have about 620mm RHA. It's full entirely possible becouse the difference between this two kinds of penetration is really big. For russian ronds made for tungsten its about ~50mm perforation, for rods DU made it's about 50-60mm. So maybe there is no discrepancies between the datas?

In DM 43 the penetration was increased by a multi-way approach: the penetrator was redesigned (another alloy was used iirc., penetrator was elongated and diameter was reduced), while the muzzle velocity was increased by redesigning the sabot (lightweight aluminium alloy) and increasing the propellant's performance.
Soviet APFSDS allways increased the penetrator's length, but the diameter of all tungsten APFSDS except for Mango and Lekalo remained the same. The same goes for the powder and the sabot construction. This means that while Soviet penetrators got longer, they also got heavier -> less muzzle velocity. Early APFSDS have 1,800 m/s, while later Mango and Lekalo (Lekalo depending on sources, Fofanov claims that muzzle velocity was increased over Mango, but more up-to-date sources claim otherwise) have a muzzle velocity of only 1,700 m/s.
American APFSDS also changed only one thing at a time. M829A1 did have a better penetrator compared to M829, but the changes to propellant and to the sabot were so small that the muzzle velocity decreased by ~75 m/s. M829A2 did have a slightly different shaped penetrator (regarding the tip) and a new alloy, but it's main difference was the new propellant and the lighter sabot. Therefore muzzle velocity increased by 105 m/s. On M829A3 the penetrator was redesigned to such an extend that it was to heavy to even reach the same muzzle velocity as M829A1 - compared to M829A2 it decreased by 125 m/s.
I.e. M829 -> M829A1: mainly changed penetrator
M829A1 -> M829A2: mainly changed sabot/propellant (projectile length and diameter stays the same)
M829A2 -> M829A3: mainly changed penetrator (diameter increases, but length increases to a stronger degree)
At the same time DM 43 had a smaller diameter, new lightweight sabot, better propellant and probably also an longer penetrator (up to 5 cm longer).

Btw:
Some people on TankNet and other sites believe in increases of about 110 mm from M829 to M829A1 or from M829A1 to M829A2.

 

[militarysta]

According to 10Tk.Bde instruktions:
3BM42 -P0:580 P2500:460
DM33 -P0:600 P2500:490
DM43* -P0:670 P2500:560

P0 - 0m
P2500 - 2500m


*there was mistake DM43 was described as DM53 (on TankNutsDaveCensorsip) what was nonsens of course...

 

[methos]

From WITU pdf-file "ANALIZA NUMERYCZNA WPŁYWU MODYFIKACJI DWUSEGMENTOWEGO PENETRATORA POCISKU PODKALIBROWEGO NA GŁĘBOKOŚĆ PRZEBICIA PANCERZA RHA":

...

 

[militarysta]

From WITU pdf-file "ANALIZA NUMERYCZNA WPŁYWU MODYFIKACJI DWUSEGMENTOWEGO PENETRATORA POCISKU PODKALIBROWEGO NA GŁĘBOKOŚĆ PRZEBICIA PANCERZA RHA":



...

Yes I know its - this dates are not common whit dated from 10 Tk.Bde using Leopard-2A4...

Or -as I said - all is OK, but this:
DM33 -P0:600 P2500:490 is achivble penetration (how many it will be for 2000m?? circa about 520mm?) an this 470mm WITU is guaraneed perforation?
In that scenario achivble perforation is about 50mm bigger then guaranteed and it will be:
DM33A1 -470mm (G) to 520mm RHA (A)
DM43A1 - 560mm (G) to ~610mm RHA(A)
Polish 120mm -500mm(G) to ~550mm RHA (A)
etc.
It make sense.
BTW -Please consider the difference between dates (in many sources) for DM53 for L-55 - 810mm and 750mm. Again -it can be difference between achievable(A) and guaranteed(G) penetration...

 

[methos]

Yes, but you forgot that you also posted the BM-42 value being 460 mm RHA at 2,500 m. The Russians certified it at 450 mm RHA at 2,000 m, so 470 mm certified penetration for DM 33 is still very low.
I.e. DM 33 is still only 20 mm to 30 mm stronger than BM-42 according to WITU and Polish Army values... imo. 10 cm longer penetrator and probably similar impact velocity at this range speak against this.

 

[militarysta]

DM33A1 have penetrator lengt 570mm, diameter 28mm, max presure 515Mpa, rod weight (during fly) 4,6kg, and Muzzle velocity1650m/s
BM42 have about penetrator lengt 452mm, diameter 31-22mm, max presure?, rod weight (during fly) 4,85kg, and Muzzle velocity 1700m/s

So Yes, DM33A1 have 118mm longer penetrator, diameter is simillar, max presure -no idea, BM42 weight more 0,25kg, and Muzzle velocity is 50m/s bigger.
In my opinion dates are quite possible:

DM33A1 470mm (G) and ~520mm(A)
3BM42 450mm(G) and ~500mm(A)
Maybe fact that DM33 have longer penetrator is "eaten" by lower at (1/4kg) penetrator weight and smaller muzzle velocity?
And in fact in both case DM33A1 have still bigger penetration values.
Int hat:
3BM42 -P0:580 P2500:460*
DM33 -P0:600 P2500:490*
too

If this dates (taken from 10Tk.Bde) are correct then 3BM42 is lossing 120mm at 2500m and Dm33 is loosing 110mm at 2500 so maybe difrencess in Vdrop aren't so big? And it can be possible becouse Dm33 have 28mm diameter and BM42 31mm in thickest place...but have slighty bigger muzzle velocity. Again for me this dates are correct.