Main Battle Tanks and Armour Technology

[militarysta]

BTW:
What really Chineese army have about APFSDS:

"In recent years, a key priority of China's tank industry has been the upgrading of 125-mm caliber tank ammunitions, particularly APFSDS. China has so far upgraded APFSDS II to APFSDS IIM, both of which have a weight of 23 kilograms, but with different velocities. The APFSDS II has a velocity of 1720 meters per second, while the IIM's velocity is 1700 meters per second.

The two types of APFSDS munitions have a penetration capacity of RHA220 mm/68.5o and RHA220mm/66.4o at a range of 2000 meters respectively. The 125-mm BTJ1 HEAT munitions have a penetration capacity of RHA180mm/68 o with behind armor effect, while the HEAT munitions displayed in earlier years have had a penetration capacity of RHA80mm/68 o with behind armor effect.

--

(Andrei Chang is editor-in-chief of Kanwa Defense Review Monthly, registered in Toronto, Canada.) "

When we convert these values to NATO 90@ plate we have:

APFSDS
APFSDS
RHA220 mm/68.5o - ~600mm RHA
RHA220mm/66.4o - ~550mm RHA

Conclusion:
1. It's next (first is was Methos battle on tank-nuts-censors-dave page about this ammo) example, that there is no super -duper chineee ammo which can perforate 800mm RHA and two Abrams one by one It's bullshit. \
2. This 550-600mm RHA (for two different APFSDS round) it late 1980 level. The late Soviet 125mm APFSDS (which were to be introduced in years 1990-1995, but were not) have bigger performance (3BM44M). So this chineese ammo for ~2008 is worse then Soviet ammo developed around ~1990.
3. 550mm RHA for older chneese round is the same like for Polish 125mm PRONIT (~540mm) which had a defective core(rod) from IMI. Propably jews sold how-konw not only to Poland
4. This ~600mm RHA is slighty worse then new Polish 125mm APFSDS (computationally~610mm RHA) whit new composite sabot. If it was possible to developed some kind of 125mm APFSDS it was possible in china -with weaker technology, but much larger budget than in Poland.


pdf.about polish 125mm ammo:
http://www.witu.mil.pl/www/biuletyn/zeszyty/20050096p/61.pdf

more about (not only polish):


120 mm Polish Ammunition for Leopard 2A4 -in english!
http://www.witu.mil.pl/www/biuletyn/zeszyty/20060097p/25.pdf
(Methos -it may be interesting for you)

MMUNITION FOR 120 MM LEOPARD'S 2A4 TANK GUN
The paper shows the dates of the Polish high-explosive ammunition family for 120 mm
Leopard's 2A4 tank gun. This presentation shows the main ammunition parameters,
indication, coding and pictures of the rounds and transport containers.

pdf: : http://www.witu.mil.pl/www/biuletyn/zeszyty/20080105p/113.pdf

Possibilities of the Use of the PAWA-1 Passive Armour Model for Protection of the Helicopter Against RPG-7

http://www.witu.mil.pl/www/biuletyn/zeszyty/20090109p/9.pdf

EXPERIMENTAL VERIFICIATION OF THE SUBCALIBRE
PROJECTILE WITH SEGMENTED PENETRATOR
Abstract: The results of the experimental verification for new 120 mm APFSDS-T projectile with
segmented penetrator were presented in this paper. The firing test was carrying out on the artillery
ranges in Nowa Dęba and Świętoszów. The aim of these tests was estimation of the 120 mm APFSDST
projectiles (with segmented penetrators) strength and ballistic parameters (ignition, muzzle velocity,
max pressure) for muzzle charge's variants.

http://www.witu.mil.pl/www/biuletyn/zeszyty/20090110p/143.pdf

INITIAL IDENTIFICATION OF THE ELONGATED
PENETRATORS RICOCHETS
Abstract. In this paper the problem of the elongated penetrators ricochets during penetration
of the oblique plates are presented. Conclusions about the influence of the pitch angle and
armour profile to penetration process were formulated basing on the critical review of the
literature.

http://www.witu.mil.pl/www/biuletyn/zeszyty/20100115p/7.pdf

EXPERIMENTAL TESTS OF THE CHOSEN TYPE OF THE ROD
ARMOUR
Abstract: Ongoing armed conflicts around the world show, that one of the most dangerous threats are
missiles with cumulative heads. Their high effectiveness, low production cost, low mass and
simplicity of use makes them very popular among terrorist and partisans forces. High penetration of
this kind of weapon makes, that it is very difficult to protect against these missiles. One of protection
method against missiles with cumulative head is application of rod armour. In the paper the
construction of armour and research station were described. The paper presents a fast camera images
recorded during the experimental tests. Basing of this images there was described destruction of the
missile during impact into rod armour. The interaction recorded by fast camera between missile and
armour was presented.

http://www.witu.mil.pl/www/biuletyn/zeszyty/20110118p/51.pdf (greate pdf!)

 

[militarysta]

CAT87'

 

[militarysta]

Forgot:




It's not form WITU, and it's not my job.

From other sources core(rod) M829A1/A2 without sabot, ballistic cap etc weight 4,6kg, the heaviest currently used M829A3 about 7kg.
For DM53 I saw about 8.35kg for all (sabot+rod+fins+ballistic cap) and about ~>5kg for rod/core only.

If
DM33 for L-44 have muzzle v 1650m/s and 11.5MJ (for rod with sabot) for all 8.35kg and rod >5kg
and
M829A2 for L-44 have muzzle 1680m/s and 11.15MJ (for rod with sabot) for all 8.7kg but rod only 4.6kg
that is almous sure that M829A2 shoud have lower perforation level -am I right?
And if trully is that M829A2 have about 650-710mm RHA for 2000m (depending on the source) then DM53 for L-44 shoud have better performance?

And what about L-55 and ~1750m/s muzzle v?

Any idea?

 

[methos]

As I remember this "new" polish 120mm APFSDS could penetrate about 540-560mm RHA at 90. on 2000m. It's almoust the same like rejected DM-43. And in WITU there are study about very very interesting new sectional core(rod) for 125 and 120mm APFSDS ammo.

Not rejected, but skipped. France uses it with the Leclerc (at least a DU version, but if I remember correctly also the tungsten version), while Saudi-Arabia, Egypt and Kuwait all fielded it with the M1 Abrams.
I'm not sure, but based on the files available on WITU's page the 120 mm APFSDS-T Wariant IV (with a penetration of 280/60° here page 9) has a chamber prssure of 515 MPa and a muzzle velocity of 1,650 m/s. The penetrator has a diameter of 24 mm. DM43A1 has a chamber pressure of 550 MPa, a muzzle velocity of 1,750 m/s and reportedly a diameter of 23 mm. So it should be better than the new Polish round. And her Jane's claims:" No armour-penetration details have been released, although the DM43A1 round is stated to be able to "defeat any currently fielded armour targets".

Interessting is also the following: The US rounds all claim a very high chamber pressure (560 MPa - M829A1, 565 MPa - M829A3) but some German's in other forums claimed that the DM53 should not be fired from the L/44 gun, because at high temperatures the pressure comes close to the maximum supported. So the American rounds should destroy the guns when fired in the desert... but: Jane's reported that the KEW-A2 APFSDS has a muzzle velocity of ~1,700 m/s, but looking at this presentation (page 14) the muzzle velocity of 1,700 m/s is achieved at an exterior temperature of ~23°C. My guess: The US base at least some of their presentations on American values. Why should they use 15°C when they don't use the metric system. 75°F (fahrenheit) seems to be a "round number", which turns out to be 23,8°C. So it might be that some values like the pressure KEW-A1 (DM43A1 licence built with JA-2 propellant) are based on "American" measurement. This would explain why Germans claim DM43A1 has a chamber pressure of 550 MPa and Americans claim it would be 580 MPa. According to the old version of the Rheinmetall website, DM63 (equivalent in terms of pressure with DM53 at 15°C) has a chamber pressure of 550 MPa.

Regarding the results of CAT '87:
You forgot to mention that it was the only time that the M1 Abrams won ;-)

 

[militarysta]

If
DM53 for L-44 have muzzle v 1650m/s and 11.5MJ (for rod with sabot) for all 8.35kg and rod >5kg
and
M829A2 for L-44 have muzzle 1680m/s and 11.15MJ (for rod with sabot) for all 8.7kg but rod only 4.6kg
that is almous sure that M829A2 shoud have lower perforation level -am I right?
And if trully is that M829A2 have about 650-710mm RHA for 2000m (depending on the source) then DM53 for L-44 shoud have better performance?

And what about L-55 and ~1750m/s muzzle v?

Any idea?

I'm not sure, but based on the files available on WITU's page the 120 mm APFSDS-T Wariant IV (with a penetration of 280/60° here page 9) has a chamber prssure of 515 MPa and a muzzle velocity of 1,650 m/s. The penetrator has a diameter of 24 mm. DM43A1 has a chamber pressure of 550 MPa, a muzzle velocity of 1,750 m/s and reportedly a diameter of 23 mm. So it should be better than the new Polish round.

But how many MJ will be have rod?

for "Wariant IV" in kg is: 7.3/4.1kg and muzzle velocity 1650m/s
for DM43 it is: 7.6/4kg and muzzle 1750m/s

So how bigg difrence is muzzle velocity ~100m/s?

 

[methos]

If
DM53 for L-44 have muzzle v 1650m/s and 11.5MJ (for rod with sabot) for all 8.35kg and rod >5kg
and
M829A2 for L-44 have muzzle 1680m/s and 11.15MJ (for rod with sabot) for all 8.7kg but rod only 4.6kg
that is almous sure that M829A2 shoud have lower perforation level -am I right?
And if trully is that M829A2 have about 650-710mm RHA for 2000m (depending on the source) then DM53 for L-44 shoud have better performance?

I believe that DM53 is similar in performance to the M289A2 APFSDS, but the energy itself doesn't say much. The muzzle energy from 120 mm DM13 to 120 mm DM33 stayed nearly the same, as did the projectile weight . Still the arrangment of the weight (no steel hull for DM33, less sabot weight) and the shape of the penetrator (L/D-ratio) changed, which increased armour penetration.
For armour penetration the length and the diameter is very important. DM53 seems to have an a little bit smaller diameter (~1-2 mm) than M829A2. Smaller diameter -> more energy per mm². The overall length of the sub-caliber projectile is a little less, but it might be that the penetrator of DM53 is longer, because it possibly extends further into the tip (there is a patent of how to make the tip also of WHA). Longer penetrator -> it will take more time (more time = more penetration) until the penetrator is fully eroded.
What remains unkown is the alloy properties. If DM53 is using a "typical WHA alloy" (typical WHA alloys have a density of 17.5 g/cm³ and absolutely no positive shear properties), then the diameter will increase more during penetration and the rod will be weaker than DU. On the other hand bolume approximations (assuming the penetrator is a perfect cylinder) based on estimated/guessed lengths show that DM53 seems to have a higher density penetrator than 17.5 g/cm³ (depending on what "approximately 5 kg" means).

And what about L-55 and ~1750m/s muzzle v?

Muzzle energy will be ~12.6 MJ (calculated using the former 11.5 MJ), Somewhere (afaik it was by Rheinmetall or Jane's) it was claimed that it has a muzzle energy of approximately 13 MJ. The energy again does not say much. But there is another important thing: materials seem to have an "optimum velocity" for penetrating (the relationship between velocity and penetration is not linear).

for "Wariant IV" in kg is: 7.3/4.1kg and muzzle velocity 1650m/s
for DM43 it is: 7.6/4kg and muzzle 1750m/s

So how bigg difrence is muzzle velocity ~100m/s?

As for kinetic energy there is a pretty common formula: 1/2 mass * (velocity * velocity). So velocity is more important regarding energy than weight, if the shape remains the same. But energy alone does not mean penetration.
In my opinion it is rather "simple": If 3BM-42M can penetrate ~600 mm RHA, then I would assume a little bit more for DM43A1. Why? The penetrator of DM43 is as long as the whole sub-projectile of 3BM-42M (which includes still ballistic cap and tracer), whereas the velocity is nearly the same.

 

[Damian]

Regarding the results of CAT '87:
You forgot to mention that it was the only time that the M1 Abrams won ;-)

That is rather surprising, M1 FCS is much more intuitive and simpler in use than completely ----ed up, non intuitive FCS of Leopard 2... And Yes, I do not like Leopard 2 FCS, firing to stationary targets was easy but to moving targets it is just tragedy, even after hours of training. M1 even with older FCS with only one sight mirror stabilized is better and faster.

 

[methos]

That is rather surprising, M1 FCS is much more intuitive and simpler in use than completely ----ed up, non intuitive FCS of Leopard 2... And Yes, I do not like Leopard 2 FCS, firing to stationary targets was easy but to moving targets it is just tragedy, even after hours of training. M1 even with older FCS with only one sight mirror stabilized is better and faster.

This is your opinion. If you ask a Leopard 2 tanky, he will say "the Leopard 2 is awesome, it has the best ergonomics and the best FCS". If you ask a M1 tanky, he will tell you the same about the M1. And you, being a fan of the M1 might not be as impartial as you should be. There are dozens of ex-East-German tank crews on the internet who say that the T-72 is awesome regarding ergonomics and usability - even some who servered on T-72 and Leopard 1s/2s

In the end the Leopard 2 has won a larger number of competitions as any other tank out there. This does not reflect exact combat value, but may be affected by user friendliness, where more impartial tank crews were using the vehicles.

 

[militarysta]

That is rather surprising, M1 FCS is much more intuitive and simpler in use than completely ----ed up, non intuitive FCS of Leopard 2... And Yes, I do not like Leopard 2 FCS, firing to stationary targets was easy but to moving targets it is just tragedy, even after hours of training. M1 even with older FCS with only one sight mirror stabilized is better and faster.

Bullshit.

FCS in Leopard-2 is called "Der Shimpanse" - think why. As I said - Steel Beast SB3 smth. smth. and PC + keybord is not tank turret whit whole controls, josick, opticks etc. Mayby I'll write more later. Aim target in Leo-2A4 FCS is even stupidly simple - and you have only 3 thinks to do when you want to aim moving target. Have You ever see Leo2A4 gunner site?

 

[Damian]

Yeah, I used Leo2 and M1 in sim, simulator is as realistic as possible, and M1 FCS is more intuitive and simpler to use. Also firing at moving targets is more simple, I do not need to remember to push a button so FCS will start to calculate adynamic lead... it is so... annoying when You need to hold button so lead can be calculated. I preffer FCS where lead is calculated automatically after lase.

 

[militarysta]

"Yes, It works!"

EXPERIMENTAL TESTS OF THE SUBCALIBRE PROJECTILE WITH
SEGMENTED PENETRATOR FOR TANK GUNS
Abstract. The results of the experimental verification for new APFSDS-T projectile with segmented
penetrator were presented in this paper. The firing test was carrying out on the artillery range in Nowa
Dęba. The aim of these tests was the verification of APFSDS-T projectiles (with segmented
penetrators) variants.

http://www.witu.mil.pl/www/biuletyn/zeszyty/20110119p/21.pdf

 

[Damian]

Great, hopefully it get in to production as soon as possible.

 

[nitesh]

The Tribune, Chandigarh, India - Nation

A small innovation will go a long way in giving the Army's T-90 main battle tanks the ability to hunt and kill in the dark - and at a fraction of the cost of imported equipment. Army engineers have integrated locally made LCD monitors to replace malfunctioning imported gadgets.

A major problem with the T-90's imported night sight was that its visual video display (VVD) unit was not ruggedised and, hence, defect prone. This resulted in the tank becoming night-blind. This was particularly the case in the hot and dusty environs of the desert.

LCD display units of the requisite size available off-the-shelf commercially have been used to replace the VVDs. According to available information, the TFT screens are available for just about Rs 3,500 as compared to a staggering Rs 25 lakh for the imported units.

While the T-90 tanks have been in service for about a decade, there have been some reports of malfunctioning or non-availability of certain electronic equipment, including those required for night or adverse weather operations. The non-availability of ammunition for its 125 mm main gun was also an issue some time ago.

 

[Kunal Biswas]

FT screens are available for just about Rs 3,500 as compared to a staggering Rs 25 lakh for the imported units.

Wow, that's a huge relief..

 

[Austin]

This interview with Chief of Tank-Automotive Directorate of the Ministry of Defence, Major-General Alexander Shevchenko , has good insight and details on Armata and other program and what according to Russian drives the concept of Universal Combat Platform

ГАБТУ положительно оценивает модернизированный танк Т-90 - ВПК.name

 

[militarysta]

www.przemysl-obronny.pl/img/wrzesien073.pdf

typical marketing BS how to "bad" german's Leopard-2A4 are bad, old, etc and polish "wonderfull" PT-91 is good.
Article powerade by Bumar - manufacurer PT-91

but..even in worst bullshit can be smth.interesting (like in Andriej Tarasenko teksts )
in this case:


It can be true?


btw: This tekst in part about engines can be interesting for friends form India

 

[methos]

Hi militarysta,
As already mentioned the value 800 - 810 mm at 2 km has been published in at least two Bundeswehr sources (a movie produced by a German TV channel jointly with the Bundeswehr and a image "poster") - this are not really reliable sources (esp. the poster), but there also has been much discussion on TankNet and similar forums.
Based on the Lanz-Odermatt equation I got an penetration of ~750 mm LOS in 270 HB steel at 60°,at 15°c which is about the average "Western estimate" and better than the "average Russian" estimate. To get a penetration of 800-810 mm LOS in 270 HB** at 60° at 15°c I need an increase by 7-8% because of better alloy properties. According to Paul L. in an older thread on TankNet: "The metalurgy involved in the DM-53 is to improve over previous designs and is reported to duplicate DU advantages in a 'high strength penetrator'. These are between 8-11%, independant of density over 1.4-1.6km impact velocity. It increasingly looks like the 800mm @ 2km figure is valid." If he is basing this statement on proper sources and not on rampant speculation, then my values seem to support the claims of 810 mm in 270 HB steel. In 230 HB steel at 60° impact angle, the LOS penetration will be 835-845 mm (with 7-8% performance increase because of alloy), which compares to an estimated 844 mm in 230 HB steel at 60° by a TankNet member named Lieste for the M829A3.*
.
The problem here is the following: The Lanz-Odermatt equoation is "nice", but it is just an approximation and far away from being pefect. So all written aboe does not say anything. It is designed mainly for tungsten rounds so all DU-estimates might be less exact. It is afaik based on data points mainly from "short" rods, with a L/D-ratio smaller than 30 (probably 15-20).
I have also some problems with the output values. It seems that all penetration values I have tried to compute are lower than reported or expected, unless we assume that the penetration values come from penetration in highly sloped targets. I have also read that earlier sometimes APFSDS performed worse against sloped armour, while according to the L-O eq. all APFSDS are better versus sloped armour. How far is also an interesting question: according to the L-O eq. all APFSDS (even the DU ones) will penetrate less than 70 cm in 270 HB steel at 0° impact angle and 15° exterior temperature. From reported values (mainly 105 mm APFSDS) the penetration does increase by ~5 cm when fred at 60° sloped steel, but believing L-O eq. it would be ~10-15 cm.
I also wonder how much the difference in muzzle velocity between L/44 and L/55 (which is equal to more than 1.5 km range) affects penetration. There is an optimum impact velocity and the longer barreled L/55 is closer to it. Zaloga assumes in his estimations for M829A1 (also he does not write on what they are based) that for this round a range of ~1.5 km is equivalent to about ~7.5 cm armour penetration, while for the values based on L-O equation the increase in
armour penetration is less than 5 cm. These values are not directly comparable, as M829A1 and DM53 have different optimum velocities, but OTOH the difference between DM53 + L/44 and DM53 + L/55 seems to be greater than the between M829A1 at 0 m and M829A1 at 1.5 km.

Edit:
Here are the datas the modelled DM53 has:
Length (overall): 745 mm
Tungsten mass: 4,681 kg
Sabot mass: 3,324 kg [sabot might be a little bit lower, I increased it's density to come up with the mv]
Accelerated projectile mass: 8,369 kg
Muzzle velocity (L/44): 1750 m/s (1670 m/s) [I didn't plan to come to the exact value]
Chamber pressure: 550 MPa [as claimed by Rheinmetall]
Propellant: 8,9 kg [Defense Update's claim]
Perforation (L/44): 750 mm @ 2 km in 270 HB steel at 60° (707 mm for the same setting)



___
*it seems that US pressure values are sometimes based on ~75° F (~22-23°C) and not on 15°C, so it might be that also the reported velocity is different from the reality, so actual armour penetration might be lower when using typical Middle European scenarios.

**270 HB = typical hardness of Soviet/Russian cast armour, 230 HB = typical weak cast armour as used in early M60s

 

[Kunal Biswas]

Interesting:

Gur Khan attacks!

 

[militarysta]

About good ERA (polish ERAWA) ability:

Some examples of test on ERAWA-1:

explanation of the signs
(Объяснение знаков)

CP - capability of protection (Возможность защиты)

CP=(H-Hw)/H

H- Guaranteed penetration RHA armour with thick "H"
Hw - real depth of perforation RHA amrour (witness) after perforation ERAWA brick

For ERAWA-1 CP is equal to:
for hit angle 60. CP =~84%
for hit angle 90. CP= ~67%

ERAWA-1 was tested against:

1. Small fire (7,63 12,7 14,5)
This fire can't detonated ERAWA brick. 7,63mm (B-32) can't perforate ERAWA external wall
2. 82mm motar spalls
fragments (shrapnels) form 82mm motar mine can't reduce ERAWA-1 CP
3. gasoline on fire - time burning 5-10min
no CP reduction
4. napalm - 5-10min
CP reduction only for 5% (CP= ~79-62%)
5.incendiary bomb of termite (3000C)
ERAWA set in fire inside brick, no CP for ERAWA after that.
6. Drop ERAWA brick for 10m hight on concrete or stell flore.
no CP reduction


ERAWA-2


ERAWA-2 CP - capability of protection (Возможность защиты) is:

1) single SC (ex:9M113) CP=95% (for 60.)
2) EFP diameter 100mm CP=94% (for 60.)
3) BK-14M HEAT CS CP=94-80% (for 60.)
4) 3BM15 APFSDS CP=57% (for 60.)
5) tandem SC (Panzerfust-3IT, PG-7VR, LAW)
CP= ~66%

second (in fact third) generation ERAWA armour - very effective against EFP, double SC, more modern HEAT warhead. This armour wasn't
optimized against APFSDS.

According to tests in WITU ERAWA-2 placed in 700mm space form hull side can protect against EFP from 200mm diameter, ERAWA-2 placed on turret roof can protected against EFP formed form 50-155mm dimeter )

One of advantages ERAWA-1/2 are small bricks (cassette) and possibility of placing close together ERA bricsk without risk loosing CP after one casette detonated. For that any flat area (ex Hull) can be cover by ERAWA in 95% In others ERA from other countries ERA bricks need 40-50mm space around the brick so any flat area can be cover in ~60-70%

 

[Kunal Biswas]

Identify Sabot Round, Is this French 140mm ?