Main Battle Tanks and Armour Technology

[pmaitra]

ERA work primary to increase erosion of both shaped charge jet and kinetic energy penetrator. However, in case of KE penetrator additional mechanism of defeating projectile are yaw effect, undesirable internal vibrations and stress and similiar to brake, crush penetrator, for shaped charge jet of course, ERA have additional stand off effect and other working mechanisms.

Very misterious working mechanism of armor protection discovered by British inventor team working on "Burlington" R&D program, was so called "whistle" effect, nobody really knows how this working mechanism can be described.

He stumbled upon it, and of course, the details will usually be secret.

You mean APFSDS that do not spin against APDS that spin? We know that APFSDS are mostly more potent, even APFSDS designed in the same time period as some APDS were more potent in armor penetration, why? I suspect it have something to do with spin effect, because materials and penetrator lenght of such projectiles was very similiar.

As we know spin effect decrease penetration capabilities of shaped charge jet, why? It's very complex problem and I'm affraid that my knowledge here is still limited. Maybe Methos can answer better in this subject, my main interest is still armor protection.

Hmmm, in fact, I get the impression it doesn't really matter whether it spins or not. Sabot will just behave like a sabot. APDS and APFSDS are both basically the same idea, a projectile within a projectile. Reading through some discussion on sabots and slugs, apparently, it is more to do with available guns (rifled-bore or smooth-bore) and doctrine; and one does not have a technical advantage over the other.

 

[Damian]

He stumbled upon it, and of course, the details will usually be secret.

These so called secrets are not so secret after all, You just need to search.

One thing I forgot to mention about is so called time of interaction between ERA and projectile. It seems that longer time of interaction is better, because ERA defeating mechanisms have more time to damage projectile.

Hmmm, in fact, I get the impression it doesn't really matter whether it spins or not. Sabot will just behave like a sabot. APDS and APFSDS are both basically the same idea, a projectile within a projectile. Reading through some discussion on sabots and slugs, apparently, it is more to do with available guns (rifled-bore or smooth-bore) and doctrine; and one does not have a technical advantage over the other.

Perhaps yes. There are many different problems. Oh one more thing. Lenght of penetrator is very important here, for penetration values longer penetrator the better, however longer projectile is not good for spin, if I remember correctly someone on TankNet said that very long projectiles are difficult to spin for some reason.

 

[Damian]

Poland is currently preparing modernization of it's Leopard 2A4 tanks fleet (128 total, with 116 in 10th Armored Cavalry Brigade, and rest in training unit), after modernization vehicle will be designated Leopard 2PL.

Basic variant of proposed Leopard 2PL

Enhanced variant called Leopard 2PL+

More below:

Google TÅ‚umacz

 

[p2prada]

Life of a tank depends on many things.

For example in current active part of tank fleet of US Armed Forces, oldest tank have... 2 years, yes it is 2 years old. This is thanks to RESET and modernization programs. Tank is completely refurbished, it's like new tank comming out of factory but in reality it was for example manufactured in 1980's.

As for T-72's, if India would modernize them in complex way, this means deep modernization, their combat values can increase, but of course everything depends on modernization program.

It all depends on the quality of the chassis. If the chassis is good, everything can be changed, including the turret.

According to Ajai Shukla a deep modernization of the T-72 will cost Rs 9 crores. That's around $2mil per tank. I don't think it will be as deep as upgrading the armour on the turret beyond ERA.

 

[Bachchu Yadav]

When whole world is moving towards Smooth bore .. Our Arjun is stick with rifled gun . DRDO is such a pathetic company , They don't wish to see future.
1. When world is stick with torrison bar suspension , they go ahead with time and inducted Pneumatic suspension which is criticised by Army as unreliable.
2. Gun is rifled but world is move over to smooth bore.

DRDO don't know what to do and what not to do .

 

[p2prada]

To upgrade/refurbish the T-72 is not a good idea.

The price is the main point of interest - is it gonna be cheaper than a normal T-90? I doubt that. Even if it would be cheaper, the chassis will have a limited lifespan, replacement will then just be required at a later time.

Upgrades are always a compromise between capability and price. The T-72 upgrades supposedly cost half that of a T-90. If the army considers a certain amount of capability has been reached with an upgraded T-72, then it makes no sense to change the tank.

The army is considering a modern, modest and obsolete force mix.

 

[methos]

One the other hand, you have every opportunity to explain the finer details. For example, I was wondering about the difference between a spinning sabot and a non-spinning sabot. Perhaps you can help?

APFSDS fired from smoothbore guns seems to have some advantages. First of all the spin-stabilization is not required - it is a waste of energy. You will need more energy (propellant/pressue/barrel length) to reach the same kinetic muzzle energy of the penetrator. APDS are limited in their length-to-diameter ratio due to the spin stabilizaztion (maximum lies somewhere between 6 to 1 or 7 to 1 L/D-ratio). This means that it does not make sense to reduce the diameter to such an extend as on APFSDS, because the mass will also decrease - the armour penetration cabilities will drop at some point. The amount of relative mass spent on the sabot will also increase.
Similiar claim exist about APFSDS and spin-stabilization (e.g. that some relation between spin ratio and projectile length make efficient long-rods impossible). If this is true... I don't know. In the end the Britts managed to field a nearly ~70 cm long APFSDS named Charm 3 (total length is ~70 cm, not only the penetrator), but at the same time both Germany and the U.S. already fielded and/or developed a further generation of APFSDS in terms of penetration imo. Indias APFSDS seems to somehow support these claims, as it is on a technological level of the 1980s.

Poland is currently preparing modernization of it's Leopard 2A4 tanks fleet (128 total, with 116 in 10th Armored Cavalry Brigade, and rest in training unit), after modernization vehicle will be designated Leopard 2PL.

Basic variant of proposed Leopard 2PL

Enhanced variant called Leopard 2PL+

More below:

Google TÅ‚umacz

Not sure... the image shows the Leopard 2A7(+) UrbOp prototype with L/55 gun, additional hull and side armour etc, but the link does not mention all features displayed in the image.

Upgrades are always a compromise between capability and price. The T-72 upgrades supposedly cost half that of a T-90. If the army considers a certain amount of capability has been reached with an upgraded T-72, then it makes no sense to change the tank.

If this is wise depends on the upgrade. Two-thirds of the combat value, and half of the life expectancy for half the price would not be really clever. Full rebuilding with T-90 life expentancy and T-90/Arjun combat characteristics could cost more than 1/2 T-90.

 

[Damian]

1. When world is stick with torrison bar suspension , they go ahead with time and inducted Pneumatic suspension which is criticised by Army as unreliable.

Actually use of HydroGas suspension system was very good decision. First advantage is lower weight and size, in 1980's and early 1990's US Army tested so called In-Arm HydroGas suspension system for all their tracked vehicles, it was lighter from then used torsion bar suspension system by at least 1 ton, and we should remember that torsion bar suspension in many tanks was upgraded in to heavier variant, so these days with use of modern materials and considering increase in torsion bars weight, it is safe to assume that HydroGas suspension system is even more lighter.

You should remember that US Army also considers complete replacement of torsion bars with hydrogas suspension system made by L3 Company.

Below list of proposed upgrades for M1 series MBT's (the supposed M1A3 variant).

http://www.gdls.com/images/pdf/Modernization/abramsmod.pdf

And the L3 suspension systems for different vehicles:

L-3 Communications Combat Propulsion Systems

US Army want to use developed for M1 FoV Type 3870 suspension:

There are also other interesting types of HydroGas suspension systems developed by L3.

Another advantage of HydroGas suspension system is that there are no openings in hull side armor for it, or there is no use of hull interior space for suspension elements, suspension modules are just bolted on to outer surface of side hull armor, thus we not only have reduction in weight and size of suspension but also increase in internal space that can be better used, it is also easier to find a space for hull belly escape hatch for example, and it can be bigger allowing for far more comfortable use.

@Methos, it is still uncertain how deep will be modernization, these are only proposals, in the end it can be Leopard 2A4 with some features of Leopard 2A5, A6 or A7 but for example with addon armor modules similiar to Evolution, Revolution or Leopard 2A4M CAN or Leopard 2NG addon armor modules.

 

[p2prada]

If this is wise depends on the upgrade. Two-thirds of the combat value, and half of the life expectancy for half the price would not be really clever. Full rebuilding with T-90 life expentancy and T-90/Arjun combat characteristics could cost more than 1/2 T-90.

Not just per tank cost. We also need to take into account the logistics infrastructure as well along with maintenance and training that already exists. It's not everyday that even the Americans develop new tanks for induction, they have mainly been upgrading their old ones.

 

[Bachchu Yadav]

@Damian .. Point is pneumatic suspension is expensive and sophisticated. Do DRDO has that capability ? It is far far away from that . They can not build a single decent revolver forget about Tank .

Rather than building a Sasta , majboot and tikau (cheap,strong and durable) products DRDO is trying to built a space age weapon to fight aliens.

 

[Kunal Biswas]

@Damian .. Point is pneumatic suspension is expensive and sophisticated. Do DRDO has that capability ? It is far far away from that . They can not build a single decent revolver forget about Tank .

Rather than building a Sasta , majboot and tikau (cheap,strong and durable) products DRDO is trying to built a space age weapon to fight aliens.

?

And have you seen pneumatic suspension in person.. ??

 

[Damian]

@Damian .. Point is pneumatic suspension is expensive and sophisticated. Do DRDO has that capability ? It is far far away from that .

I do not know if DRDO can manufacture such suspension, DRDO is besides that state woned research and development organization, so it should not manufacture such suspension at all.

What I know is that more and more AFV's will use HydroGas suspension system, even new US IFV developed under GCV program will most likely use HydroGas suspension system. Nobody should ignore advantages given by such suspension.

 

[pmaitra]

I agree that DRDO should outsource things like pneumatic suspension to companies like Tata, L&T, Mahindra, Ashok-Leyland etc..

 

[p2prada]

I do not know if DRDO can manufacture such suspension, DRDO is besides that state woned research and development organization, so it should not manufacture such suspension at all.

What I know is that more and more AFV's will use HydroGas suspension system, even new US IFV developed under GCV program will most likely use HydroGas suspension system. Nobody should ignore advantages given by such suspension.

DRDO only designs stuff, not manufacture.

The Army found the suspensions to be acceptable.

 

[Damian]

HydroGas suspension systems are designed and manufactured for a long time.

For example BMD airborne infantry fighting vehicles use it and nobody complains about reliability, French Leclerc, British Challenger 2, South Korean K1/K1A1 and Japanese Type 90 use them also for a long time and I never heard even single word about poor reliability.

Challenger 2 with latest TES-H up armor package weights 74 tons (!) and suspension withouth any modifications can handle that weight, barely but still do the job.

 

[pmaitra]

Shall we change the title to Main Battle Tanks and Relevant Technologies instead? It will broaden the horizon. Otherwise, I'll have to delete many off topic posts, but I don't want to, because most of the posts here are very valuable.

 

[Damian]

Then rename it.

 

[pmaitra]

No, we'll keep the same title, but do post anything relevant to tanks. Don't restrict yourself to armour alone.

 

[pmaitra]

Best is to take the advantages of active protection and reactive armour and roll them into one formidable armour system!

ERA + APS = Relikt!

Any details or photos on this?

 

[Damian]

?

4S23 Relikt is ERA alone, active protection systems have different codenames, for example Drozd-1, Drozd-2, Arena, Shtora, Warta, Zaslon these are several developed in USSR and later Russia/Ukraine.

The best combination is:

1) Dynamic protection composed from ERA and composite armor with reactive components,
2) Active protection, both soft and hard kill,
3) Proper camouflage to decrease thermal, electromagnetic radiation, and also to lower visibility in human eye.