Arjun Main Battle Tank (Mk-1 & Mk-2)

Ankit Kumar

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I read that 969 units will be upgraded.
The original plan was Rhino project. A large number have already been upgraded. The newer upgraded ones will have DRDO MK2 ERA tiles and an uprated 1000 hp engine too.

The project called to upgrade around 1500 tanks. A large number have already underwent it.

In addition the older ones which are to go out first will receive few upgardes like ERA and smoke grenade launchers too.

Numbers are sketchy.

Out of 2400+ of this type upto 1800 will see various levels of improvements.
 
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Gautam

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CVRDE has called a tender to supply 8 units of cooling ducts for their new 1500 hp engine:

Screenshot (737).png

It would be safe to assume that the engine's development is complete. Bench tests are likely to begin soon. Engine design:
Screenshot (629).png


The cooling system:
Screenshot (631).png

The engine features a waste gate turbocharger:
Screenshot (632).png

This engine would probably feature in the Arjun Mk-2 &/or NGMBT. The new tanks are also going to get composite wheels:
Screenshot (626).png

Screenshot (627).png

Screenshot (624).png

The new tanks will also get the newer High Nitrogen Steel armour.
1633421147700.png


NGMBT was sanctioned in 2019:
1633421092573.png

Projects seems to be progressing well. NGMBT will get a crewless turret. Don't know if they will stick to the Arjun's 120mm rifled gun though. There was work going on to develop a 125mm smoothbore gun. No updates on that yet

Now we wait for an update on the CVRDE's 700hp engine for future IFVs:
Screenshot (633).png
 

Gautam

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CVRDE has put out a tender for fabricating a new tank chassis for testing purposes. There are 2 tanks in development currently; the NG-MBT & the DRDO/L&T Light Tank :

The chassis is supposed to be fabricated by a private company. The pvt. company is likely L&T Defence. The program is divided into 3 milestones, the program will conclude with in 18 months from the date of issue of contract. Here is a summary of items that need to be delivered in all 3 milestones :
Screenshot (745).png

Now lets get into the details of the work in every milestone. Starting with Milestone 1:

GNMBT-FICV chasis-split_page-0001.jpg


Milestone 2:
GNMBT-FICV chasis-split_page-0002.jpg

Milestone 3:
GNMBT-FICV chasis-split_page-0005.jpg

In Milestone 2 you can see a lot of switches, plugs, relays, connectors etc. being purchased from two German companies: MTU & RENK. These 2 companies supply the engine & transmission for the Arjun Mk-1/1A tanks. The Arjun is powered by the MTU MB 838 Ka-501 V10 liquid-cooled turbocharged diesel engine producing 1400 hp coupled with a RENK supplied epicyclic gear box.

The K9 Vajra used the MTU MT 881 Ka-500 V8 water-cooled diesel engine producing 1000 hp coupled with an Allison X1100-5A3 cross-drive transmission.
H2020011684113.JPG

So if this new chassis is getting the same engine/transmission set up as the Arjun this must be the NG-MBT right ? But in Milestone 1 you can see CVRDE wants 22 tons of SPADE 500 steel Medium Hardness Armour (MHA) plates to be supplied. But the NG-MBT was supposed to use High Nitrogen Steel (HNS) as the non-reactive armour. That was also one of the reasons why you needed the new 1500 hp engine to get a high power to weight ratio.

It seems they are going for downgraded armour & are getting an off-the-shelf engine for the NG-MBT. Almost like they want to get the tank rolling ASAP & make incremental improvements later. Maybe the MoD told them to hurry up.

The estimated weight of the NG-MBT was 41 tons. With the MHA that should reduce down to 36-37 tons. If they remove the ERA for high altitude operations the weight can be less than 35 tons. Maybe this is the new light tank they are going for now.

There has been news reports of the light tank based on the K9's chassis being dropped. The tender also says CVRDE will provide the engineering drawings of the chassis to the selected company. If it was the K9 chassis what drawing would CVRDE provide ? They don't own the IP for that chassis, the Koreans do.
1633525323021.png

The 58 ton Arjun Mk-1 with a 1400 hp engine has a power to weight ratio of 24 hp/ton where as the K9 is at 21.3 hp/ton. The 41 ton NG-MBT with the 1400 hp engine would be at 34.15 hp/ton. If they can reduce the weight to 35 tons then it would be 40 hp/ton. This combined with the Arjun's 120 mm rifled gun would make it a potent tank.

The TATA/DRDO Kestrel/WhAP weighs 25 tons & has a power to weight ratio of 24 hp/ton. The WhAP has been deployed in Ladakh. Maybe we should try to get a 105 mm on this along with the new 700 hp engine. An upgraded WhAP & a light tank working with the T-72s would be a significant capability boost up North.

We will need to find lighter armoured vehicles for amphibious ops in the future. The 43 ton T-72 aren't a great option for beach landing. May be this tank can eventually replace the 1900+ T-72 tanks of the Army.

CVRDE has also released a tender for manufacturing their in-house designed Low Voltage Displacement Transducer (LVDT) for powering the tank's systems:
Screenshot (746).png
 

Chain Smoker

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CVRDE has put out a tender for fabricating a new tank chassis for testing purposes. There are 2 tanks in development currently; the NG-MBT & the DRDO/L&T Light Tank :

The chassis is supposed to be fabricated by a private company. The pvt. company is likely L&T Defence. The program is divided into 3 milestones, the program will conclude with in 18 months from the date of issue of contract. Here is a summary of items that need to be delivered in all 3 milestones :
View attachment 21293
Now lets get into the details of the work in every milestone. Starting with Milestone 1:

View attachment 21290

Milestone 2:
View attachment 21291
Milestone 3:
View attachment 21294
In Milestone 2 you can see a lot of switches, plugs, relays, connectors etc. being purchased from two German companies: MTU & RENK. These 2 companies supply the engine & transmission for the Arjun Mk-1/1A tanks. The Arjun is powered by the MTU MB 838 Ka-501 V10 liquid-cooled turbocharged diesel engine producing 1400 hp coupled with a RENK supplied epicyclic gear box.

The K9 Vajra used the MTU MT 881 Ka-500 V8 water-cooled diesel engine producing 1000 hp coupled with an Allison X1100-5A3 cross-drive transmission.
View attachment 21296
So if this new chassis is getting the same engine/transmission set up as the Arjun this must be the NG-MBT right ? But in Milestone 1 you can see CVRDE wants 22 tons of SPADE 500 steel Medium Hardness Armour (MHA) plates to be supplied. But the NG-MBT was supposed to use High Nitrogen Steel (HNS) as the non-reactive armour. That was also one of the reasons why you needed the new 1500 hp engine to get a high power to weight ratio.

It seems they are going for downgraded armour & are getting an off-the-shelf engine for the NG-MBT. Almost like they want to get the tank rolling ASAP & make incremental improvements later. Maybe the MoD told them to hurry up.

The estimated weight of the NG-MBT was 41 tons. With the MHA that should reduce down to 36-37 tons. If they remove the ERA for high altitude operations the weight can be less than 35 tons. Maybe this is the new light tank they are going for now.

There has been news reports of the light tank based on the K9's chassis being dropped. The tender also says CVRDE will provide the engineering drawings of the chassis to the selected company. If it was the K9 chassis what drawing would CVRDE provide ? They don't own the IP for that chassis, the Koreans do.
View attachment 21295
The 58 ton Arjun Mk-1 with a 1400 hp engine has a power to weight ratio of 24 hp/ton where as the K9 is at 21.3 hp/ton. The 41 ton NG-MBT with the 1400 hp engine would be at 34.15 hp/ton. If they can reduce the weight to 35 tons then it would be 40 hp/ton. This combined with the Arjun's 120 mm rifled gun would make it a potent tank.

The TATA/DRDO Kestrel/WhAP weighs 25 tons & has a power to weight ratio of 24 hp/ton. The WhAP has been deployed in Ladakh. Maybe we should try to get a 105 mm on this along with the new 700 hp engine. An upgraded WhAP & a light tank working with the T-72s would be a significant capability boost up North.

We will need to find lighter armoured vehicles for amphibious ops in the future. The 43 ton T-72 aren't a great option for beach landing. May be this tank can eventually replace the 1900+ T-72 tanks of the Army.

CVRDE has also released a tender for manufacturing their in-house designed Low Voltage Displacement Transducer (LVDT) for powering the tank's systems:
View attachment 21292
Remember NGMBT is our universal combat programme so most likely it is light tank based on NGMBT chasis.
IMG_20211006_210951.jpg

Any idea about the engine ? I think it's 1000hp. I hope they put 120mm gun or that new 125mm it will make it superior than any counterpart. What about turret will it be unmanned just like NGMBT.
 
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Gautam

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Any idea about the engine ? I think it's 1000hp.
It thought it would be the 1000 hp too. But it seems they are going for an exact replica of the Arjun's engine/transmission set up. I guess that makes sense as this would allow the new tank to tap into the Arjun's production line.
I hope they put 120mm gun or that new 125mm it will make it superior than any counterpart.
In all due probability it would be the 120mm rifled. The 125mm smoothbore won't be ready soon enough.
 

Chain Smoker

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It thought it would be the 1000 hp too. But it seems they are going for an exact replica of the Arjun's engine/transmission set up. I guess that makes sense as this would allow the new tank to tap into the Arjun's production line.

In all due probability it would be the 120mm rifled. The 125mm smoothbore won't be ready soon enough.
It's soo confusing if it's 1400 hp engine then it must be not light tank but why they are using MHS when DMR 1700 and HNS is there it doesn't make sense.

Just look at sitting arrangements there will be 3 crew on chasis so it's NGMBT chasis but that would make turret unmanned and will require autoloader.
IMG_20211006_211528.jpg
 
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Gautam

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It's soo confusing if it's 1400 hp engine then it must be not light tank but why they are using MHS when DMR 1700 and HNS is there it doesn't make sense.
That's what I am confused about too.
Just look at sitting arrangements there will be 3 crew on chasis so it's NGMBT chasis but that would make turret unmanned and will require autoloader.
Making an autoloader isn't a big problem. I do hope the new turret has enough internal space to load the longest of rounds. The longest rounds right now for the Arjun's 120mm rifled gun are the thermobaric & the PCB rounds. It would be a shame if the autoloader couldn't handle those.
IA's requirement is 30HP/ton.

A light tank weighing 35T would need 1000HP. The NGMBT weighing 45T would need 1400HP.
A 35t tank with a 1000 hp engine would be ideal logistically. But that gives us 28.6 hp/ton not 30. The projected weight for the NG-MBT was 41 tons. A 6 ton weight decrease is not improbable given the use of MHA.
 

randomradio

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A 35t tank with a 1000 hp engine would be ideal logistically. But that gives us 28.6 hp/ton not 30.

Okay. 1050HP. 😐

The projected weight for the NG-MBT was 41 tons. A 6 ton weight decrease is not improbable given the use of MHA.

But that's not necessarily the all-up weight of the tank. I guess they are only trying to meet the old FMBT PSQR which asked for a 40T tank.

Also, each tank needs to be attached with a mine plough, which adds 5+ tons by default. Currently our T-90s use T-72s and T-55s with ploughs. So our tanks literally line up when traversing through a mine field.

But I'd definitely like to see it weigh 35T, although I don't believe it's actually necessary.
 

Hydra

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Arjun is a nato standard Tank, logicality speaking NG MBT too should be anato standard one. As nato is moving towards 130/140 mm tank gun, IA will also ask for such gun on NG MBT, DRDO should pro active start developing such calibre gun here or else be prepared for seeing another saga.
 

Lolwa

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Arjun is a nato standard Tank, logicality speaking NG MBT too should be anato standard one. As nato is moving towards 130/140 mm tank gun, IA will also ask for such gun on NG MBT, DRDO should pro active start developing such calibre gun here or else be prepared for seeing another saga.
Or just license produce whatever gun Nato decides. We have seen what happens when we make Nato-Equivalent hardware..
The Russian 152mm and Nato 140mm is still a long way into the future.
 

randomradio

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Or just license produce whatever gun Nato decides. We have seen what happens when we make Nato-Equivalent hardware..
The Russian 152mm and Nato 140mm is still a long way into the future.

One of the worst ideas is to make our own tank and then import the gun. The only thing worse than that is to import the engine.

Anyway, our NATO-equivalent hardware is pretty good. What the Arjun suffers from is design, and the fact that the army doesn't want it. If the army wanted it, we would have seen hundreds already ordered.
 
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Lolwa

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One of the worst ideas is to make our own tank and then import the gun. The only thing worse than that is to import the engine.

Anyway, our NATO-equivalent hardware is pretty good. What the Arjun suffers from is design, and the fact that the army doesn't want it. If the army wanted it, we would have seen hundreds already ordered.
Nah we could just license produce the l/55 but make the ammunition ourselves. All nato countries have done that. Or we could take the Korean version of the l/55. In any case we need to shift to smooth bore cannons with 700-800mm rha apfsds tungsten/DU.
Arjun has lot of flaws but we need to shift to a three man autoloader with l/55 and a better turret and hull design along with more work on ERA,NERA and it's coverage as well as cage armour.
 

randomradio

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Nah we could just license produce the l/55 but make the ammunition ourselves. All nato countries have done that. Or we could take the Korean version of the l/55. In any case we need to shift to smooth bore cannons with 700-800mm rha apfsds tungsten/DU.
Arjun has lot of flaws but we need to shift to a three man autoloader with l/55 and a better turret and hull design along with more work on ERA,NERA and it's coverage as well as cage armour.

Although it's advanced by our current standards, L55 is also an old gun now. Anyway, the NGMBT's main gun will be Indian, plus it's expected to be 125mm. There's also a pretty good chance we are going for ET guns.
 
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Gautam

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I suppose because prototyping with routine metal/alloy is comparatively quicker and easier due to possibility of using already existing tools at L&T @Gautam, @randomradio
That's not the case. Tanks have multiple layers of protection. If we go from inside the hull to outside the order would be:

1. The chassis : Usually made out of rolled steel plates called Rolled Homogeneous Armour (RHA). This is pretty common for all modern tanks.

2. Non-Reactive Armour (NERA) : This layer is added on over the RHA. NERA is usually a combination of metals, ceramics & composites sandwiched together layer-by-layer. Each layer adds a certain property to the NERA. The Arjun for example used the Kanchan NERA, the exact composition of the Kanchan remains classified. The sandwiching allows the NERA to be lighter than what it would be had it been a single composition of that thickness & protection. This is where the current contention lies. We knew that the NG-MBT would use High-Nitrogen Steel (HNS) in combination with ceramics & composites for the NERA. That would make the NERA more capable than the Kanchan which uses RHA. HNS is stronger than RHA but is also heavier. Now it seems they are going to use SPADE 500 Medium hardness Armour (MHA) steel instead of the HNS. The MHA is lighter than RHA & offers lesser protection. This looks like a weight reduction measure.

3. Explosive Reactive Armour (ERA) : ERA is added on over the NERA. As the name suggests, ERA explodes in an outwardly direction when hit. The explosive force repels & deflects the round from digging into the tank. Unlike NERA, ERA can be exhausted & thus needs to be reloaded. A tank can operate just fine without them, though one layer of safety will be missing. DRDO has its own ERA that is used on the Arjun Mk-1A & the upgraded T-72s. I think the T-90s use Russian ERA, we have not upgraded those yet.

4. Active Protection System (APS) : Consists of Soft kill & Hard kill systems. We have so far deployed the Soft kill system. Hard kill APS is still under development.
But that's not necessarily the all-up weight of the tank. I guess they are only trying to meet the old FMBT PSQR which asked for a 40T tank.

Also, each tank needs to be attached with a mine plough, which adds 5+ tons by default. Currently our T-90s use T-72s and T-55s with ploughs. So our tanks literally line up when traversing through a mine field.

But I'd definitely like to see it weigh 35T, although I don't believe it's actually necessary.
The paper says "combat mass" of the revolutionary design is 41 tons as opposed to the 54 tons for the evolutionary design.
Screenshot (754).png

Screenshot (755).png

During the design study weight from the following have been considered:
Screenshot (756).png

I think combat weight & all up weight are the same thing.
 

Lolwa

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Although it's advanced by our current standards, L55 is also an old gun now. Anyway, the NGMBT's main gun will be Indian, plus it's expected to be 125mm. There's also a pretty good chance we are going for ET guns.
I hope we don't go for the 125. L/55 is superior gun.
 

AbRaj

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That's not the case. Tanks have multiple layers of protection. If we go from inside the hull to outside the order would be:

1. The chassis : Usually made out of rolled steel plates called Rolled Homogeneous Armour (RHA). This is pretty common for all modern tanks.

2. Non-Reactive Armour (NERA) : This layer is added on over the RHA. NERA is usually a combination of metals, ceramics & composites sandwiched together layer-by-layer. Each layer adds a certain property to the NERA. The Arjun for example used the Kanchan NERA, the exact composition of the Kanchan remains classified. The sandwiching allows the NERA to be lighter than what it would be had it been a single composition of that thickness & protection. This is where the current contention lies. We knew that the NG-MBT would use High-Nitrogen Steel (HNS) in combination with ceramics & composites for the NERA. That would make the NERA more capable than the Kanchan which uses RHA. HNS is stronger than RHA but is also heavier. Now it seems they are going to use SPADE 500 Medium hardness Armour (MHA) steel instead of the HNS. The MHA is lighter than RHA & offers lesser protection. This looks like a weight reduction measure.

3. Explosive Reactive Armour (ERA) : ERA is added on over the NERA. As the name suggests, ERA explodes in an outwardly direction when hit. The explosive force repels & deflects the round from digging into the tank. Unlike NERA, ERA can be exhausted & thus needs to be reloaded. A tank can operate just fine without them, though one layer of safety will be missing. DRDO has its own ERA that is used on the Arjun Mk-1A & the upgraded T-72s. I think the T-90s use Russian ERA, we have not upgraded those yet.

4. Active Protection System (APS) : Consists of Soft kill & Hard kill systems. We have so far deployed the Soft kill system. Hard kill APS is still under development.

The paper says "combat mass" of the revolutionary design is 41 tons as opposed to the 54 tons for the evolutionary design.
View attachment 21307
View attachment 21306
During the design study weight from the following have been considered:
View attachment 21308
I think combat weight & all up weight are the same thing.
Thanks for the detailed explanation.
So cant we replace RHS with HNS on later date after prototyping etc ?