Arjun vs T90 MBT

[DivineHeretic]

The best options for Himalayan activity is to have dedicated light tanks with addon upgrades with Armour modules / slat/net Armour and APS both soft and hard.. >>

Okay,thats surprising. To think armor technology has come so far to enable a light tank to compete with ajeya.
But then it fails to explain why the IA cancelled the rfp for light tanks?
Holding territory in the plateau region near ladakh will require armor in conjunction with attack helis IMHO

 

[Dejawolf]

You doubt ? ,+180cm to be precious and that is..

These are modules can be reactive as well as NERA, Or hybrid module as its lighter and compact..

well upgraded, yeah sure, and against HEAT. but not the mk.1 base armour, that'd be less than 1000mm vs HEAT.
and as for the leopard 2A5, i was talking about the PHYSICAL thickness.

 

[Kunal Biswas]

Its not Armour technology but design..

Can you provide me with some link and report of cancellation from RFI for Light tanks, Afaik there is no word yet..

Okay,thats surprising. To think armor technology has come so far to enable a light tank to compete with ajeya.But then it fails to explain why the IA cancelled the rfp for light tanks?

------------------------------------------

Didn't i tell, that your less than 1000mm vs heat etc from a gaming site ( Source ) that is again assumed from late 80s development, I have provided creditable info in this thread go through it..

Why are you repeating questions.. ?

well upgraded, yeah sure, and against HEAT. but not the mk.1 base armour, that'd be less than 1000mm vs HEAT.

 

[JBH22]

@Kunal sometime back you posted a thread on the possible acquisition of light tanks from Poland.

Any update on this deal?

 

[kshkumsin]

@Kunal sometime back you posted a thread on the possible acquisition of light tanks from Poland.

Any update on this deal?

i am eager to know about it too

 

[Archer]

this is like arguing with religious people..
crew overhead cover? it seems like you don't understand how compartmentalized ammunition works. the system is simple. you put the ammunition inside a separate ammunition bunker, like this one for example:

now the bunker side walls needs to be pretty damn thick, at least 40-50mm of steel. on the roof, you add a plate that is much thinner, and loosely bolted on, and you have a secure blast door for access into the bunker. now. if the ammunition bunker is hit, from the side for example, instead of the rounds exploding into the crew compartment, the propellant gases are vented upwards through the thinner roof plate blowing it off, thus saving the crew from being cooked alive. naturally, the tank is rendered combat-ineffective, while the ammunition cooks off, and it might catch fire, but it will give the crew time enough to escape alive, and possibly drive the tank out of danger

now, on the arjun, the ammunition storage looks like this:

this is an ammunition stowage rack. it is not a blast door. those round things grabs onto the back of the cartridge and holds it in place.
however, if any of the rounds in the ammunition bunker is hit, those levers will break, the stub of the round will fly into the interior with a propellant jet following it, and the heat of the round will cause the propellant of the nearby rounds to catch fire as well, causing a chain reaction of fiery death. finally, the heat and pressure will cause the plastic explosive in the HEAT and HE rounds to detonate, ripping the turret rear apart in the welds, and possibly partially ltugging the turret off at the race ring.

Dont much visit the forum anymore but you are mistaken about these being open ammunition storage. Look at the hull ammo and you'll see each round gets its own blast cover which is then kept in place by those heavy levers. The ammo rack also separates each round from the other with thick steel as is obvious in those pics. The Arjun also has a weakened blast door section above the ammo compartment. Its not as elegant as keeping the entire ammo rack behind a single bulkhead but then again, the Arjun protects each round with its own separation & cover case, as versus keeping an entire exposed ammo rack behind a single bulkhead where the rounds are not protected from each other but merely in exposed clamps.
In the MK2, the above approach (completely separated bulkhead) is followed, the MK1 approach was clearly because of KISS ( reducing maintenance demands on the Army) and to reduce weight.

 

[Archer]

lol. no. btw, the ammunition safety measures was part of the leopard 2 prototype back in 1979. it took indian engineers 32 years to figure out how it's supposed to work?
as for all your talk about sufficient armour.. no, it is not.

in that red area, it is vulnerable to RPG, ATGM, 100/120/125mm tank rounds. so is the leopard 2A4, however, it's ammunition is compartmentalized.
so a hit in that area isn't going to kill the crew and completely destroy the tank. oh and btw, if you squint, notice the ammunition storage doors on the mk.2 are the same as on the mk.1 so no, i think the ammunition storage on the Mk.2 is the same as on the mk.1

The MK2 has a newer separated ammunition storage system based on the western tank model, so no, its not the same as MK1, so those concerns are unecessary.

you obviously didn't understand what i was writing. like electricity,the hot expanding gases follow the path of least resistance. in the case of the leopard, it's through the thinner roof panel, simply because the ammunition blast walls and door is thicker than the roof.
on the Arjun, the cylindrical container of each round is more resistant, than the ammunition stub so the ammunition is vented INTO the turret interior where the crew is. the location is BAD, because even in a hulldown position, the turret ammunition is exposed. on a T-72 or T-90, at least the ammunition is down under the turret floor(if the crew doesn't store all the extra ammunition around the turret interior)

If you look at Arjun pics, you will see two doors right above the ammunition storage (turret) area, clearly meant to mimic the western blast door method. They are clearly not for reloading as the Arjun rack does not permit rounds to be hoisted into the tank from that position. The Arjun just follows a simpler method to achieve the same aims of protection, it encases each round in a heavy ballistic steel container, in an armoured rack more or less, with blast covers kept in place with heavy levers (hence the oversized arms and the lock/unlock positions) as versus mere clamps. Its not improbable either that the top of the rack has deliberately weakened sections to coincide with the hatches. Net, its a simpler method to approximate the automated door + separate bulkhead of the western tanks, and is more similar to the Merkava (earlier Marks) which had blast proof/fireproof containers for each round. FWIW, the separation of ammunition from the crew was a design feature of the Arjun way back from the 1980's thanks to issues with the T-72s which were lost when burning debris from misfired rounds found their way into the hoist and then into the carousel itself.

 

[Archer]

once again we dont know the protection level of kanchan armor with respect to it's weight to arrive at any conclusion.And it too must have undergone some R&D since it's introduction.

It would be know it all rubbish (not you) to dub the kanchan weight inefficient. Kanchan has been through several revisions and design improvements as India advanced in both metallurgy and manufacture through the 80's to today, plus there is no shortage of test data from modern rounds fired at various ballistic targets. In the early 1990's, the Army was so impressed with Kanchan they wanted it to be used to upgrade all tanks (Vijayanta and T-72s), its a different matter that the engines (especially on the former) did not permit it to be easily added. The upgraded T-72s may well have Kanchan on the glacis and not just Gen-1 ERA.
As regards the T-90s, their armor too has been developed from tech for the Arjun as the Russians played slow on transfer of tech for certain armor modules. Their performance has passed IA requirements.

 

[Damian]

It would be know it all rubbish (not you) to dub the kanchan weight inefficient. Kanchan has been through several revisions and design improvements as India advanced in both metallurgy and manufacture through the 80's to today, plus there is no shortage of test data from modern rounds fired at various ballistic targets. In the early 1990's, the Army was so impressed with Kanchan they wanted it to be used to upgrade all tanks

Western armors to increase their protection, also seems to be weight inefficent, as they started to use very dense and thus heavy, heavy metal alloy modules.

This is because protection against shaped charges and kinetic energy projectiles is difficult to achieve, you can have relatively light and not very dense armor that protects well against shaped charges, but protection against kinetic energy projectiles will be very low, or the opposite. The problem is how to achieve balanced protection.

NATO in the end due to increase in kinetic energy projectiles penetration characteristics, decided to go in to heavy metal alloys and better armour steel alloys and types. But this means increase in weight, because also it is needed to keep balance.

You think that Arjun Mk1 is heavy? With 57 tons it represents weight of M1A1 from 1985, currently used M1 variants are weighting 63 tons this is 6 tons more, and 80-90% of this weight increase is from armor improvements.

The only weight efficent armor that can provide balanced and good protection against both shaped charges and kinetic energy projectiles, would be armor made from CNT's, ADNR's or both, currently used materials have not so good characteristics or are expensive like B4C.

 

[Archer]

The constant complaints by the same gentleman that "how can India develop this ...etc etc.. without a single design to its credit" clearly demonstrate he might want to understand how product development in India works. In the case of India, the Arjun has been constantly refined from prototype to prototype, with a harsh user demanding nothing but the best & then putting the tank through rigorous trials and sending it back for redesign whenever any defect was noticed. Net, there are two ways to develop systems - the simpler but more expensive method of series production and then solving defects Mark by Mark (with the risk of having defective tanks being sent into combat - try to research the issues about the Challenger 1 in ODS and how its FCS was not upto the task more often than not, despite claims of the longest ranged kill and what not). The other method is to constantly prototype and keep producing LSPs and then prototype again and not series produce a definitive Mark till most issues are addressed. This may lead to bad press, constant accusations of delay, overbudget etc but ends up in multiple designs packed into one program, some of which may end up as radical departures from the original plan.
For instance, the original Arjun started as a 40 ton class tank with a 105mm gun - today its a 60 ton class tank with a 120 mm class gun and future Arjuns may differ even more significantly. The Arjun of the 1990s had an analog FCS with a Gen1 thermal imager and no vetronics. Todays Arjun has an all digital FCS with integrated vetronics (which work with the automotives), and a Gen3 TI, with the MK2 in trials coming up with an all new HK TI Commanders Sight and many other improvements. This may have been classified as a significant product improvement in most other programs. India is funding it as part of the Arjun program itself and may even commission a MK3 to produce as the definitive variant.
Simply put, its India's money and India's choice.
Importing yesterdays models from Germany would have been the most disastrous choice for India to make, especially with the whimsical choices employed by German politicians who seem to have lost the appetite and gonads for supporting fellow democracies in wartime.
Not so long ago, Indian paramilitaries were denied HK MP-5s for use in COIN ops. HK got a well deserved boot up the backside apparently, judging from recent reports as its not part of the tendering for the massive order for assault rifles noted by the Army.
Similarly, when India asked for a 1500 hp powerpack, we were given a larger, less powerful 1400 hp one by MTU citing German Govt opposition. Today, the same country sends delegations to India to sell the Eurofighter as they are too broke to buy it. How times change. Its a different matter that Indian engineers working with MTU ruggedized the 1400 hp powerpack to develop sufficient power (without derating) and making it more resistant to dust & particulate damage than other more "modern" engines.
Having said that, the advantages of India developing its own systems is obvious. Today, it stands on the cusp of making its own designs, hard won experience, and not merely inducting yesterdays tanks at a few hundred thousand Euros and then presiding over a showpiece military.

 

[Archer]

Western armors to increase their protection, also seems to be weight inefficent, as they started to use very dense and thus heavy, heavy metal alloy modules.

This is because protection against shaped charges and kinetic energy projectiles is difficult to achieve, you can have relatively light and not very dense armor that protects well against shaped charges, but protection against kinetic energy projectiles will be very low, or the opposite. The problem is how to achieve balanced protection.

NATO in the end due to increase in kinetic energy projectiles penetration characteristics, decided to go in to heavy metal alloys and better armour steel alloys and types. But this means increase in weight, because also it is needed to keep balance.

You think that Arjun Mk1 is heavy? With 57 tons it represents weight of M1A1 from 1985, currently used M1 variants are weighting 63 tons this is 6 tons more, and 80-90% of this weight increase is from armor improvements.

The only weight efficent armor that can provide balanced and good protection against both shaped charges and kinetic energy projectiles, would be armor made from CNT's, ADNR's or both, currently used materials have not so good characteristics or are expensive like B4C.

Damian, Arjun's armor has been through multiple revisions and is fairly well appreciated by its end user, the Indian Army who has both manufacturer cites (from western and Russian OEMs) to compare its protection against, plus access to tech partners and ammunition. Net, it has not remained static since the early 80's - when the first Kanchan was productionized.

The way forward for the Arjun to strike a balance is clearly to incorporate both passive and active measures. Expect the Arjun to field APS using both soft kill (to begin with, as has been confirmed for the MK2) and hard kill (as is in development). Our preferred partners are the Israelis but whosoever offers the right tech and access to it, will be chosen.

 

[Damian]

Damian, Arjun's armor has been through multiple revisions and is fairly well appreciated by its end user, the Indian Army who has both manufacturer cites (from western and Russian OEMs) to compare its protection against, plus access to tech partners and ammunition. Net, it has not remained static since the early 80's - when the first Kanchan was productionized.

But this is exactly what I said. Armor evolution was a process, I suspect that Kanchan might have the similiar evolution route like Burlington, from a low density armor mainly optimized against shaped charges, to a less weight efficent, but densier armor with more balanced protection against KE and CE ammunition types.

The way forward for the Arjun to strike a balance is clearly to incorporate both passive and active measures. Expect the Arjun to field APS using both soft kill (to begin with, as has been confirmed for the MK2) and hard kill (as is in development). Our preferred partners are the Israelis but whosoever offers the right tech and access to it, will be chosen.

Active Protection System is a completely different matter that I am not discussing here.

 

[Kunal Biswas]

No updates, the tank is in row with other light tanks in RFI..

@Kunal sometime back you posted a thread on the possible acquisition of light tanks from Poland.

Any update on this deal?

 

[HarshaHalsur]

Re: Army scuttles Arjun trials to push through T-90 purchase

Only someone very poorly educated person can call A BT and T-34 series suspension as better. Do you know what suspension these vehicles used? It was Christie suspension, a very primitive and problematic, and soviets leave it behind as soon as possible.

In fact Soviets allways wanted to use the same torsion bars suspension systems as Germans did.

For example the original T-34 was intended to be replaced as quickly as possible with T-34M that had torsion bars suspension system instead of Christie suspension, but war jeopardized all these plans and in the end the T-34 replacement become T-44 that was designed from 1943 and become manufactured in late 1944, but never participated in the second world war.

So :



It does not mean you know a lot about tanks. I suggest to read some good books. For example Боевитые машины Уральвагонзавода Т-54 / Т-55 there is a bit about T-44, maybe some other books, I would need to dig in my collection.

As for smoothbore guns, they were used by Soviets and NATO because spin is not desired in modern ammunition, in fact modern ammunition is not spin stabilized, it is fin stabilized but they do not spin.

Spin effect is not good for shaped charge warheads. If projectile spin, the shaped charge jet will have reduced penetration capability because spin is making formation of jet difficult.

French had a lot of problems with this, so they designed a more complex HEAT ammunition, where there was outer case, and inner warhead mounted on ball bearnings, so outer case of projectile was spin stabilized when the warhead itself was not. But this increased complexcity of projectile and manufacturing costs.

As for APFSDS spin is also not desired, very long rods can even break during flight if they were spin. This is because of forces that are effecting penetrator during flight as well as penetration. And this was a problem even without spin effect, I heard that during some initial tests with longer penetrators in late 1980's and early 1990's ended up with penetrators breaking in to parts during flight, it was solved out but spin is a no go for modern ammunition.

There was a lot of reasons to resign from rifled guns. And I am amazed that even if top militaries of the world, proved that rifled guns are obsolete, and not needed any more as tanks armament, some people are so attached to that myth of rifled gun, that even if this makes their weapon system obsolete, they would stick to it.

Good discussion : Just use a discarding sabot... rifled gun becomes the same as smooth bore. Fin stabilized rounds ca be fired from rifled guns. the advantage of rifled guns is that itg ives more power and accuracy and range as well compared to smooth bore. HEAT rounds are totally out of date( ceramic use in the armour).
but can be used against light vehicles. the one that really matters is first hit and what round will u use in that first round. I am including >5km ATGMs (Nag, Helina). which means the advantage of smooth bore over rifle is over. and ow the rifled gun can score over light vehicles to clear the battle field.

 

[HarshaHalsur]

The constant complaints by the same gentleman that "how can India develop this ...etc etc.. without a single design to its credit" clearly demonstrate he might want to understand how product development in India works. In the case of India, the Arjun has been constantly refined from prototype to prototype, with a harsh user demanding nothing but the best & then putting the tank through rigorous trials and sending it back for redesign whenever any defect was noticed. Net, there are two ways to develop systems - the simpler but more expensive method of series production and then solving defects Mark by Mark (with the risk of having defective tanks being sent into combat - try to research the issues about the Challenger 1 in ODS and how its FCS was not upto the task more often than not, despite claims of the longest ranged kill and what not). The other method is to constantly prototype and keep producing LSPs and then prototype again and not series produce a definitive Mark till most issues are addressed. This may lead to bad press, constant accusations of delay, overbudget etc but ends up in multiple designs packed into one program, some of which may end up as radical departures from the original plan.
For instance, the original Arjun started as a 40 ton class tank with a 105mm gun - today its a 60 ton class tank with a 120 mm class gun and future Arjuns may differ even more significantly. The Arjun of the 1990s had an analog FCS with a Gen1 thermal imager and no vetronics. Todays Arjun has an all digital FCS with integrated vetronics (which work with the automotives), and a Gen3 TI, with the MK2 in trials coming up with an all new HK TI Commanders Sight and many other improvements. This may have been classified as a significant product improvement in most other programs. India is funding it as part of the Arjun program itself and may even commission a MK3 to produce as the definitive variant.
Simply put, its India's money and India's choice.
Importing yesterdays models from Germany would have been the most disastrous choice for India to make, especially with the whimsical choices employed by German politicians who seem to have lost the appetite and gonads for supporting fellow democracies in wartime.
Not so long ago, Indian paramilitaries were denied HK MP-5s for use in COIN ops. HK got a well deserved boot up the backside apparently, judging from recent reports as its not part of the tendering for the massive order for assault rifles noted by the Army.
Similarly, when India asked for a 1500 hp powerpack, we were given a larger, less powerful 1400 hp one by MTU citing German Govt opposition. Today, the same country sends delegations to India to sell the Eurofighter as they are too broke to buy it. How times change. Its a different matter that Indian engineers working with MTU ruggedized the 1400 hp powerpack to develop sufficient power (without derating) and making it more resistant to dust & particulate damage than other more "modern" engines.
Having said that, the advantages of India developing its own systems is obvious. Today, it stands on the cusp of making its own designs, hard won experience, and not merely inducting yesterdays tanks at a few hundred thousand Euros and then presiding over a showpiece military.

the best and that most matters in times of war.. is that Arjun can be locally manufactured at low cost. ppl argue that arjun adn t90 are diif class.. we are not comparing an airplane with tank. if tis different class then their cost should also different. arjun 3.1million US$ t90 4million US$ ..... t90 shud have cost significantly less if its lesser class like al khalid tank.2.5milU$

 

[Damian]

Re: Army scuttles Arjun trials to push through T-90 purchase

Good discussion : Just use a discarding sabot... rifled gun becomes the same as smooth bore. Fin stabilized rounds ca be fired from rifled guns. the advantage of rifled guns is that itg ives more power and accuracy and range as well compared to smooth bore. HEAT rounds are totally out of date( ceramic use in the armour).
but can be used against light vehicles. the one that really matters is first hit and what round will u use in that first round. I am including >5km ATGMs (Nag, Helina). which means the advantage of smooth bore over rifle is over. and ow the rifled gun can score over light vehicles to clear the battle field.

These are some complete bollocks. To give a velocity similiar to the smoothbore gun in rifled gun you need more pressure, you decrease gun service life, rifled guns are inferior in penetration capabilities to smoothbore guns. For example British L27A1 fired from L30A1/L55 have a penetration estimated to ~500mm RHA it was fielded in 1999, while DM53 fire from a shorter Rh-120/L44 also fielded in 1999 have a penetration estimated to ~750mm RHA.

And again, explain me where is bigger accuracy of rifled gun over modern smoothbore gun, when in all competitions, tanks armed with smoothbore guns were more accurate despite fact that British Challenger 2 uses fire control system with similiar performance to other modern tanks as well as a fact that L30A1 is the most modern and most capable rifled gun designed for a tank up to this day.

It starts to be hilarious, when the whole world move on and replaces obsolete rifled guns with modern smoothbore guns, it seems that in India there is permament fanclub of obsolete rifled guns.

But this is probably based on a fact that only smoothbore guns that are avaiable for India to trails are guns of 2A46 and 2A46M family that are less accurate than western guns like the Rh-120 and guns based on it's design, or French CN-120/26.

 

[Dejawolf]

Dont much visit the forum anymore but you are mistaken about these being open ammunition storage. Look at the hull ammo and you'll see each round gets its own blast cover which is then kept in place by those heavy levers. The ammo rack also separates each round from the other with thick steel as is obvious in those pics. The Arjun also has a weakened blast door section above the ammo compartment. Its not as elegant as keeping the entire ammo rack behind a single bulkhead but then again, the Arjun protects each round with its own separation & cover case, as versus keeping an entire exposed ammo rack behind a single bulkhead where the rounds are not protected from each other but merely in exposed clamps.
In the MK2, the above approach (completely separated bulkhead) is followed, the MK1 approach was clearly because of KISS ( reducing maintenance demands on the Army) and to reduce weight.

yes, the walls on the rack are thicker than on the leopard. good. the ammunition racks are proofed against secondary spalling. but don't try and tell me they're proof against a direct hit.
if you look in the picture of the Arjun ammunition rack you see an air gap between the roof an rack.
now tell me, what offers more resistance, Air or steel? well, steel is denser than air, which means IF(a very large if) the ammunition explosion is vented upwards, it will stop at the door, and instead vent into the crew compartment..
but personally i doubt that, because there are no end caps on the rounds in the ready rack. as that would reduce the loading time.
more likely the weakest point would be the "heavy duty" round clamps. it would break like a twig, rocketing the end cap into the interior, followed by highly volatile propellant gases. the container wouldn't fare much better, probably rupturing in the process.

 

[Dejawolf]

If you look at Arjun pics, you will see two doors right above the ammunition storage (turret) area, clearly meant to mimic the western blast door method. They are clearly not for reloading as the Arjun rack does not permit rounds to be hoisted into the tank from that position.

Yes, the doors are not for reloading.

and they are present on the Mk.1 in fact, they're identical. Personally i think the doors are a convenience for the production of the Arjun. You can assemble the whole rack, and then hoist it down into the turret. and afterwards just bolt the roof shut. and also the

if you base your opinion of the Mk.2 having an isolated ammunition compartment on the fact it has something that resembles blast doors on the roof,
then, well no, that doesn't really prove anything.

 

[Dejawolf]

i noticed something...

 

[Damian]

Wait a second, this means serious and unacceptable weak zone! If this looks that way as it looks, I can't believe that someone allowed for such design drawback! :shocked:

This would mean that only left front of the turret is protected... I would really start to ask difficult questions if I would be the citizen of India.