Arjun Main Battle Tank (MBT)

[zraver]

Even now it is very good tank, just seen it my self last year, even manage to measure some of the armour and compaire it with other T series tank. Gun is good and so it LAHAT, done lot of research my self.

measuring armor is worthless, your not comparing identical steels and hen figuring the impact angle and armor angel. The two tanks use different protection methods.

I cant say much, what they have got inside, but from the protection part and what they got in terms of firepower, they are Ok, but not against ARjun tank. AL Khalids armour is not that good. DRDO is working on increasing the velocity of gun. I think it can take out Al Khalids. [/quuote]

Rifled guns have a velocity problem- the higher the velocity the faster the barrels wear out. Spin from the rifling also poses problems when designing APFSDS rounds.

Arjun has FLIR system, which is modern, it has BMS and that system is not avaliable on T 90 or any other version of T series with IA, as far as training of three men crew is concern, it appears that you are confusing the Arjun with IA's training, when ARjun, will be inducted method of training will be change.

Last I knew the Catherine system by THALES on the T-90 was superior. The Arjun does not have a CITV. If it has a BMS I'll update my info.

I dont think you are at all aware about the investment gone into the Arjun and the factory they setup, CAG will hang govt if that happens.

Investment alone doesn't require you buy something if it doesn't work. The Arjun is a good tank, but its rapidly getting dated because of all the delays and political infighting.

As far as engine is concern, local engine will be produce by the private company provided sufficent orders are recieved by IA, which is not coming,

will be and are being mean two different things.

its suspension is so good that IA want it on FMBT. BMS of next generation is ofcouse needed.

that is what I said.

Actually if you look at the requirement of IA which is more then 3800 tanks, Arjun or T90 alone cannot done that role, what we need is combination of both. We need light as well as heavy tank for IA.

You don't need both, you can make do with both, but you don't need them. 1 good design with commonality of parts is better than 2 totally different logistics tails.

I dont agree with you, Arjun tank is so good that it can withstand direct hit from point blank range, whereas T 90 S can be easily penetrated and once that happen Crew is history.

true, but not the whole truth. The T-90M has much better protection

Arjun is made to withstand punishment and is made keeping in mind crew safty, where as T90S is based on number doctrine of Second world war.

Over simpliication. The T-90 originally was built to meet the needs of the USSR who had a less technically skilled non-homogeneous population and a technologically advanced enemy.

 

[Yusuf]

Welcome e Zraver and Texasjohn. A I think the DRDO is moving over to smoothbore rifle for the Arjun.

 

[zraver]

Welcome e Zraver and Texasjohn. A I think the DRDO is moving over to smoothbore rifle for the Arjun.

I have heard that, but have not seen it. India has acess to the IMI 120mm L44 used on the Merkava IV so its an easy upgrade. The IMI gun can also fire all NATO standard 120mm ammuntion and the Lahat.

 

[Texasjohn]

I have heard that, but have not seen it. India has acess to the IMI 120mm L44 used on the Merkava IV so its an easy upgrade. The IMI gun can also fire all NATO standard 120mm ammuntion and the Lahat.

I thought they already had. Looking at the pic of the Arjun firing the Lahat. That would not be possible if it wasn't a smoothbore, would it??

 

[zraver]

I thought they already had. Looking at the pic of the Arjun firing the Lahat. That would not be possible if it wasn't a smoothbore, would it??

No the Lahat is a >100mm saboted missile. You can increase/decrease the size of the Sabot to fit any gun from 105mm-120mm. If you look at the picture you can see the sabot halves flying off the round.

 

[Yusuf]

Tell me something. The Challenger also has a riflebore and is considered a good tank. So why the hole noise about smoothbore vs riflebore?

 

[zraver]

Tell me something. The Challenger also has a riflebore and is considered a good tank. So why the hole noise about smoothbore vs riflebore?

The MoD is undergoing trials with a Challenger equipped with a 120/L55 IIRC. As good as the CHARM 3 ammo is, modern armor is calling for better guns. The 120mm rifled gun used to compensate with accuracy but modern fire control systems negate this so the higher velocity is what is important. Even then any 120mm round might be too small.

It seems all the developments intended for the late Cold War are now maturing and a new armor/gun race is underway. We are soon going to be in a situation where 120/125mm gun tanks will be pounding on each other with little effect. The US with its superb heavy weight M829A3 is spending a large ammount of money developing the MRM top attack muntions as another indicator of how well protected modern tanks are getting. A 1970's vintage gun just isn't modern anymore.

 

[sayareakd]

Arjun gun is good one

and it has muzzle velocity of 1650 m/s and above.

it can take out modern tank from 5 KM with FSAPDS.

not to mention CLGM which has 6-8 KM range.

 

[zraver]

Arjun gun is good one

and it has muzzle velocity of 1650 m/s and above.

it can take out modern tank from 5 KM with FSAPDS.

not to mention CLGM which has 6-8 KM range.

Assuming the the quoted number of 1650m/s is correct. That is 100m/s slower than the 120mmL/55, the Chinese 125mm L50 (Al Khalid's gun) and the 125mm L/52 of the T-90.

The only way to increase impact energy with a velocity of 1650 is to use a heavier and thus DU round. Now here is an important question- is the Arjun's gun a bagged charge system like the L11A5? I can speculate more once I know the answer to this question.

If the round and charge are fully encased like the 120mm increasing the weight of the penetrator is possible to a far larger extent than if the penetrator and the primary charge are loaded in two pieces.

 

[sayareakd]

Assuming the the quoted number of 1650m/s is correct. That is 100m/s slower than the 120mmL/55, the Chinese 125mm L50 (Al Khalid's gun) and the 125mm L/52 of the T-90.

The only way to increase impact energy with a velocity of 1650 is to use a heavier and thus DU round. Now here is an important question- is the Arjun's gun a bagged charge system like the L11A5? I can speculate more once I know the answer to this question.

If the round and charge are fully encased like the 120mm increasing the weight of the penetrator is possible to a far larger extent than if the penetrator and the primary charge are loaded in two pieces.

honestly i dont know much about that, but i sure know that my figures are from 2002. I have been informed by friend that DRDO is working on increasing the its muzzle velocity.

Even the Israeli's are impressed with Arjuns gun.

 

[zraver]

honestly i dont know much about that, but i sure know that my figures are from 2002. I have been informed by friend that DRDO is working on increasing the its muzzle velocity.

Even the Israeli's are impressed with Arjuns gun.

Kinetic energy such as used by APFSDS depends on several factors. The basic formula is half mass (.5m) times (x) velocity sqaured (v^2) with the result measured in megajoules (mj). A system that uses a bagged charged set up with multipiece ammo limits the leangth of the penetrator. You can increase the penetrator thickness, but byy how much I do not know. Some early Russian rounds had a length to diamter ratio as high as 16-1 but most modern rounds fired from spool style sbot set ups are closer to 30-1. here the single piece ammo is superior becuase you can sink the round into the charge to increase leangth of the penetrator.

Once you've got that decided, it moves into the realm of energy transferance and resistence to deformation. At this point the math and technical details go way past my ability to explain them. But in a nut shell a round has to hit and be able to transfer all of its mass on to the penetratign tip without deforming. If the round deforms on impact the energy transferance is interruppted and the surface area in contact with the surface being struck increases by a massive amount further reducing the amount of energy reaching the impact point.

part 2 coming soon.

 

[zraver]

If your round can hit and kep its form the imparted energy is important. A ighter round travelling 1650 m/s will not outperfom an equally well designed round of the same weight going 100m/s faster. Make that other round ehavier and faster and the lighter and slower round is outperformed even more.

On top of this is the effect of heavy RA which is designed to induce sheer on the side of the penetrator. A heavier round is generally sturdier and more resistent to sheer. Contact-5 for example was designed to defeat late Cold War era US and NATO APFSDS rounds. The US responded with the M829A3 which could defeat Contact-5, Russia responded with the kacktus heavy ERA. What has the Arjun been doing in this race between armor and gun power? Its most likely opponent is a Chinese designed, pakistani built tank that uses a decent layering of armor technologies- RHA, Ceramic and ERA. I am not sure the Arjun's gun is up to the task.

 

[vish]

zraver:

Sir, is the velocity of the T-90S' gun enough to counter Pakistani armor?

 

[zraver]

zraver:

Sir, is the velocity of the T-90S' gun enough to counter Pakistani armor?

I don't know, its a high velocity gun at 1750m/s but the other part of the equation is the round it fires.

 

[Texasjohn]

Zraver ( and the other tank dudes!) where can I read up more on tank guns and various rounds on-line? I appear to know just enough about tanks and armor to be dangerous.

Hey! I'm not too proud to admit I don't know enough.

 

[Soham]

Kinetic energy such as used by APFSDS depends on several factors. The basic formula is half mass (.5m) times (x) velocity sqaured (v^2) with the result measured in megajoules (mj). A system that uses a bagged charged set up with multipiece ammo limits the leangth of the penetrator. You can increase the penetrator thickness, but byy how much I do not know. Some early Russian rounds had a length to diamter ratio as high as 16-1 but most modern rounds fired from spool style sbot set ups are closer to 30-1. here the single piece ammo is superior becuase you can sink the round into the charge to increase leangth of the penetrator.

Once you've got that decided, it moves into the realm of energy transferance and resistence to deformation. At this point the math and technical details go way past my ability to explain them. But in a nut shell a round has to hit and be able to transfer all of its mass on to the penetratign tip without deforming. If the round deforms on impact the energy transferance is interruppted and the surface area in contact with the surface being struck increases by a massive amount further reducing the amount of energy reaching the impact point.

part 2 coming soon.

If your round can hit and kep its form the imparted energy is important. A ighter round travelling 1650 m/s will not outperfom an equally well designed round of the same weight going 100m/s faster. Make that other round ehavier and faster and the lighter and slower round is outperformed even more.

On top of this is the effect of heavy RA which is designed to induce sheer on the side of the penetrator. A heavier round is generally sturdier and more resistent to sheer. Contact-5 for example was designed to defeat late Cold War era US and NATO APFSDS rounds. The US responded with the M829A3 which could defeat Contact-5, Russia responded with the kacktus heavy ERA. What has the Arjun been doing in this race between armor and gun power? Its most likely opponent is a Chinese designed, pakistani built tank that uses a decent layering of armor technologies- RHA, Ceramic and ERA. I am not sure the Arjun's gun is up to the task.

Thank you for the details sir.
I love solving physics numericals based on tanks ...

Just one question sir,
When you said that the only way to increase the effectiveness is to get heavier rounds... doesn't the extra weight make its trajectory more parabolic ? Won't that lead to inaccuracy ?

 

[zraver]

Thank you for the details sir.
I love solving physics numericals based on tanks ...

Just one question sir,
When you said that the only way to increase the effectiveness is to get heavier rounds... doesn't the extra weight make its trajectory more parabolic ? Won't that lead to inaccuracy ?

Not if you keep the velocity up, the M829A3 is a 8-10kg round after sabot (actual weight is secret) and supposedly travels 1555m/s. The M829A3 is also 830+mm long with a L/D ratio of around 30/1.

TexasJohn, hang around tank-net. There are real experts there who make an almost professional study of armor. They've got the actual formulas used to break down suspected performance or rounds and armor. All I've got is my experience and some real basic formulas and rules of thumb.

 

[Ray]

zraver,

What is the opinion on the tank net?

 

[Soham]

Not if you keep the velocity up, the M829A3 is a 8-10kg round after sabot (actual weight is secret) and supposedly travels 1555m/s. The M829A3 is also 830+mm long with a L/D ratio of around 30/1.

Sir,
What about the length of the round ? (considering the total mass to be constant)

Will the change in length affect the KE ?

 

[Daredevil]

Sir,
What about the length of the round ? (considering the total mass to be constant)

Will the change in length affect the KE ?

Soham, changing the length (assuming same mass) doesn't change the KE per se but the impact it might create when it hits the armor of a tank will be different (not sure in which direction) just like pointed rounds create more impact than flat rounds despite having same kinetic energy.