Armoured Vehicles Discussion Thread

nachiket · Post by **nachiket** » 20 Feb 2011 08:01

Prasad wrote:Err a couple of posts from the past (ca 2007 by JCage)

.......

Do we really need to rehash stuff from 2007 again on this thread about Arjuns armour? jmt.

This is exactly why JCage left in the first place. And Anujan is right. Many of the perceived "problems" with the Arjun started out as speculation or lifafa articles in the media. Some were genuine no doubt and were eventually solved. Others like the infamous "torsion bar" were hatchet jobs which were carried out just because the Arjun was desi maal and foreign manufacturers with their propagandu machine didn't really like the competition.

chackojoseph · Post by **chackojoseph** » 20 Feb 2011 08:17

d_berwal wrote:
Coming to GSQR specs: My assumption would be it does not meet the current requirement that's why K-5 on Arjun MkII . (otherwise why would you do that, it carries a 2.5 ton weight penalty approx)
{It might have met the 1995 specs not present}

Or could be that Army is willing to go for less protection for lighter armour. IIRC, Army was trying to reduce Arjun Armour by deploying a team there. They ended in saving just a 100 or so kgs. Hence they must have decided on lower protection like that of T-90S.

kvraghav · Post by **kvraghav** » 20 Feb 2011 08:51

^^^
Thanks anujan for showing how a speculation became a problem in couple of posts.d_berewal goes to my ignore list.

sudeepj · Post by **sudeepj** » 20 Feb 2011 09:06

d_berwal wrote:
sudeepj wrote: 1. The ERA bricks provide protection by way of the E(xplosion) and the R(eaction), not their slope. Hence, IMO, its incorrect to categorize them as sloped armor.
2. The Arjun Turret is faceted, but doesnt have the slope one sees in the Merkava IV etc. Having said that, one needs to understand the composition of the armor package and what material properties it relies on on defeat APFSDS darts and shaped charge jets.

As per my limited understanding of the subject, it is advantageous to place Ceramic armor (the kind Kanchan is) in a flat profile to defeat APFSDS, while perforated armor (the applique sloping blocks on Leo2A6) is best placed in a highly sloped profile.

All this has been repeatedly rehashed in this forum since the days of 'JCage' etc., so I am not really adding anything new here.

The point I would like to make, berwal babu is, did you notice the qualifiers I put in the two statements about armor packages? The reason I put those qualifiers in, is because I am not an expert in the field.

What gives you the confidence to make bold confident statements about the relative efficiencies of armor packages, without being at least a dabbler in the field? Whatever conclusions you have reached using your skillset should have been as obvious to the DRDO designers, who are doers in the field. What makes you think they did not take an informed decision? Material properties is quite an arcane field, even people with pretty good technical backgrounds are circumspect about making definitive statements in this area.

1. what disadvantage will kanchan give if its sloped:
- will the LOS thickness not actually increase ?

- Isnt Chobham ( its more of a ceramic composite) , but why do we see challenger series MBT having sloped Armour?

- I know a pure ceramic is not useful for sloped Armour, but Kanchan is a composite Armour (Kanchan composite had a composition of ceramic, alumina, fiber glass and some other such materials mixed)

A little googling may be of some help, berwal babu.

http://en.wikipedia.org/wiki/Chobham_armour
Ceramic tiles draw little or no advantage from sloped armour as they lack sufficient toughness to significantly deflect heavy penetrators. Indeed, because a single glancing shot could crack many tiles, the placement of the matrix is chosen so as to optimise the chance of a perpendicular hit, a reversal of the previous desired design feature for conventional armour. Ceramic armour normally even offers better protection for a given areal density when placed perpendicularly than when placed obliquely, because the cracking propagates along the surface normal of the plate.[7] Instead of rounded forms, the turrets of tanks using Chobham armour typically have a slab-sided appearance.

As for your other questions, they are just that, they are questions, they are NOT answers as to why the Arjun was not chosen as the MBT of the Indian Army. You are greatly mistaken if you think you are posing some deep questions the answers to which will uncover the DRDO as frauds and Army as lily white.

These questions are elementary, that would be asked by any 10th std student, but your tone is one that suggests that these are original insights and if only the Arjun designers had thought of these, the Arjun would have been all TFTA. If people like me and you can think of these questions, please understand that they would definitely occur to scientists whose job it is to design armor packages. To me its obvious, they must have taken these basic insights into account when designing the Arjun turret. (The hull is sloped enough).

In any case, the answers to your questions, are complex, and are best provided by someone who knows what Kanchan is made of, what the relative arrangement of the materials within is and so on. The designers are not talking, for rather obvious reasons.

The only 'proof' lies in how the kanchan protects its crew from darts and jets and we have repeatedly heard confident assertions that it can withstand T72 APFSDS from point blank range.

rohitvats · Post by **rohitvats** » 20 Feb 2011 09:37

The base armor of T-90 is toast against any decent APFSDS and hence, the requirement for ERA. Otherwise, why lug around additional weight?

Add to the fact that the already fvcked up TWR of T-90 goes down further due to added weight of ERA.

On a different note: K-5 is said to offers protection against APFSDS as well. Which actually is an indictment of armor on T-90 and other tanks; the western APFSDS has reached a stage that Russian armor cannot survive without ERA.

suryag · Post by **suryag** » 20 Feb 2011 10:07

These questions are elementary, that would be asked by any 10th std student, but your tone is one that suggests that these are original insights and if only the Arjun designers had thought of these, the Arjun would have been all TFTA. If people like me and you can think of these questions, please understand that they would definitely occur to scientists whose job it is to design armor packages. To me its obvious, they must have taken these basic insights into account when designing the Arjun turret. (The hull is sloped enough).

Very true. And of everything the easiest to prove/disprove for a scientist is how slope would help the armour? Even if we assume that they didnt get this great idea there are always lots of people in design review meetings who hardly understand anything or pay enough attention to the design review discussion but in order to make their presence felt ask some inane question at the end, this slope would come under such a category fo questions
One of the reviewer: Have you evaluated the right gradient to make this armour more effective ?

chackojoseph · Post by **chackojoseph** » 20 Feb 2011 11:23

A lot of people know the basics. But, let me attempt my understanding.

When tanks were made by the British, they made it out of metal to withstand wwII munitions. Then, there was a race to make tanks and add on protection.

Many types of protection came out. AA Guns, Armour, chaffe and flares etc. Armour is just one part of the protection and the main one.

Armor have evolved different types. Composite, ERA, Smart/intelligent and active armour. It dosen't matter what you use as long as it gives protection.

Chobum is the most known Armour in copmpsite type. ERA was developed as an alternative and not an evolutionary step of composite.

In composite, there is more volume with same weight. For exapmple, weight may remain 100 kg, but the volume of the armour may increase from 100 mm to 200 mm. So, when the volume increases (sandwhiched by various density materials like ceramics), the kinetic energy dissepiates as the projectile traveles various levels.

ERA means that there is gun powder and it explodes deflecting the projectile.OR The armour bricks shift towards the impacting projectile and hence the kinetic energy is absorbed.

In smart/intelligent armour there are sensors which predict the vulneribility of your armour to withstand the impact.

In active armour, there are "also" offensive measures like interception of incoming projectile.

My squence of armor also means passive to active armor.

Composite armour may mean volume, but, sureshot protection even from projectiles from close quarters. For example Kanchan is tested against the kinetic pressure and other paramaters exhibited by various projectiles from possible distances.

ERA might be lighter and more compact, the tiles may fail to react and explode.

Smart/ Intelligent means electronics. It helps to to understand where you shoukd take the hit.

Active armour is a mix of different composite/ERA/smart/intelligent/offensive armour and techniques.

Now, every thing has trade off like weight, space, amount of protection, surviability etc.

sunny y · Post by **sunny y** » 20 Feb 2011 12:55

People might want to look at this debate between Anonymous & Ghorcharrah on Mr. Ajai Shukla's Blog that happened last year.... Fantastic....

http://www.blogger.com/comment.g?blogID ... 6094973617

Thanks

Drishyaman · Post by **Drishyaman** » 20 Feb 2011 17:54

Issues with Tin Can :

1. Night vision needs upgradation.
2. Heat issues with the computer.
3. Lack of AC.
4. Lack of APU.
5. Gun less accurate than the Arjun’s Gun.

Army is deploying Arjun in the desert and Tin Can is too cool to operate in the desert.

d_berwal sahab will have problem with Arjun MK – II as well.

Surya · Post by **Surya** » 20 Feb 2011 19:50

d_berwal sahab will have problem with Arjun MK – II as well.

Yeah - waiting for the next nonsense from the tin canners

Drishyaman · Post by **Drishyaman** » 22 Feb 2011 19:26

The first prototype demonstration of Ajun Mark II will take place by June 2011. By 2013-14, the first batch of about 30 tanks will roll out of the HVF, said Sivakumar.
http://flonnet.com/stories/20110311280510000.htm

Sanku · Post by **Sanku** » 22 Feb 2011 19:48

It is a commentary (a sad one?) that this thread moves only when T-90 and/or Arjun bashing happens.

keshavchandra · Post by **keshavchandra** » 22 Feb 2011 20:30

Arjun is our first indig. project even DRDO not have any experience in tank design. With time this project will mature.

RoyG · Post by **RoyG** » 22 Feb 2011 21:29

^^It has matured.

ramana · Post by **ramana** » 23 Feb 2011 03:09

Front line article

Desert Ferrari

SPECIAL FEATURE: DRDO

‘Desert Ferrari' and more

WITH the Army in possession of 100 of the 124 Arjun Mark I Main Battle Tanks it had ordered, the Combat Vehicles Research and Development Establishment, the Defence Research and Development Organisation (DRDO) facility that designed and developed the tank, has good reason to feel proud and prepare with confidence for the greater challenges that lie ahead. ......

......

The completion of the Arjun Mark I project has brought a sense of accomplishment on the CVRDE's vast shop floors. The project was originally sanctioned in May 1974 at a cost of Rs.15.5 crore and a timeline of 10 years. The deadline and the cost were revised in 1980, 1987 and 2000. The cost at the time of the closure of the project in March 1995 was Rs.305.6 crore.

Five formidable-looking Arjun tanks rolled out of the HVF premises on August 7, 2004, marking the culmination of a 30-year saga of struggle that battled technology denial regimes, the Army's constantly varying requirements, difficulties in organising field evaluations, increase in number of prototypes, and so on. On that day, M. Natarajan, then Chief Controller (Armament and Combat Engineering), DRDO and formerly CVRDE Director, who had been associated with the Arjun project from the beginning, said, “Weapons of this kind take a generation to build.… When the Army wanted us to design a tank comparable with those in the United States, Germany and France, we took it up as a challenge. We had little experience then.…” ( Frontline, August 27, 2004). Natarajan later went on to become Scientific Adviser to the Defence Minister and DRDO Director-General.

P. Sivakumar, Director, CVRDE, narrated the Arjun saga. A few tanks were delivered to the Army's 43rd Regiment for trials. Five phases of these trials were held at Pokhran and Mahajan in Rajasthan in winter, when the temperature plummets to 5° Celsius, and in summer, when the mercury sizzles at more than 45° C, and on different kinds of terrain. The Army was keen that Arjun should be able to ford waterbodies. Each tank covered 5,000 kilometres and fired 500 rounds of ammunition.

The Army wanted a third party to assess the tanks and called in experts from Israel. They subjected the tanks to more tests at the Mahajan range and were so impressed that they called it “a desert Ferrari”.

Arjun Mark I has imported content of more than 55 per cent, which includes the engine and the gun control system, which are from Germany, and the gunner's main sight, which is from Belgium. The tank has an excellent weight-to-power ratio, good mobility and accurate firepower. It weighs 58.5 tonnes and compares well with different heavy class of tanks available in the world. It has indigenously developed “Kanchan” armour, which can defeat different kinds of ammunition, and a 120mm rifled gun besides a robust transmission system and a flexible hydro-pneumatic suspension. The remaining 24 of the 124 tanks ordered by the Army will be produced by June this year, Sivakumar said.

As for Arjun Mark II, the CVRDE Director said the major upgrades would include missile-firing capability against long-range targets; panoramic sight with night vision to engage targets effectively at night; containerisation of the ammunition wing; enhanced penetration of Arjun's ammunition; a variety of ammunition; and a painted surface that will camouflage the tank.

Other major upgrades, according to Sivakumar, are explosive reactive armour; an advanced air-defence gun to shoot down helicopters; a plough to remove mines; and an advanced land navigation system. Arjun Mark II will have sensors that can detect lasers fired by an enemy tank and alert the tank to fire smoke grenades that confuse the laser. The first prototype demonstration of Ajun Mark II will take place by June 2011. By 2013-14, the first batch of about 30 tanks will roll out of the HVF, said Sivakumar.

T.S. Subramanian

Copyright © 2010, Frontline.

Thanks TSS! Looks like they are confident as they are giving measurable milestones.

Rohitvats,
Are these 124 tanks in one formation or dispersed all over?

rohitvats · Post by **rohitvats** » 23 Feb 2011 03:21

ramana, the first batch of 124 tanks are with two regiments and AFAIK and each is under different formation.

As per media reports, one regiment is with Armored brigade of 24 RAPID while other is with (I) Armored Bde of XII Corps in Jaisalmer.

Cybaru · Post by **Cybaru** » 23 Feb 2011 05:39

Anujan wrote:
d_berwal wrote:
So sorry if I came down hard on your speculation.

Nice Catch...

suryag · Post by **suryag** » 23 Feb 2011 07:13

So the production line will be idle for a year and a half(from june 2011 to 2013) before mk2 comes out ? Any idea how many pre production mk2 tanks will be made ?

Singha · Post by **Singha** » 23 Feb 2011 07:56

Mk2 demo in June 2011 indicates almost all the upgrades are ready and tested piecemeal on Mk1 last few yrs - like the lahat missile, new land navigation system and mine ploughs.

inshallah, livefist, broadsword and others will be soon releasing pics of this new beast.

NRao · Post by **NRao** » 23 Feb 2011 08:11

pandyan wrote:
The Army wanted a third party to assess the tanks and called in experts from Israel. They subjected the tanks to more tests at the Mahajan range and were so impressed that they called it “a desert Ferrari”.
Third party assessment..... thank god they didnt bring the russians.

Data point: DTI has a nice article on what we can expect future tanks to have. The Trophy being "inducted" on the Israeli tanks.

Rahul M · Post by **Rahul M** » 23 Feb 2011 08:30

suryag wrote:So the production line will be idle for a year and a half(from june 2011 to 2013) before mk2 comes out ? Any idea how many pre production mk2 tanks will be made ?

how so ? the 2nd 124 Mk1 order is there.

chackojoseph · Post by **chackojoseph** » 23 Feb 2011 08:40

So, 93 upgrades has been palmed off as 91 defects by some resident expert.

pralay · Post by **pralay** » 23 Feb 2011 08:44

Singha wrote:Mk2 demo in June 2011 indicates almost all the upgrades are ready and tested piecemeal on Mk1 last few yrs - like the lahat missile, new land navigation system and mine ploughs.

inshallah, livefist, broadsword and others will be soon releasing pics of this new beast.

singha ji,
I remember they mentioned in old articles that the upgrades for mkII will come in batches.
So the first batch will be come out with first set of upgrades and so on .
it was supposed to take 2014(<< I dont remember this exactly) to for rolling out mkII with all upgrades.
(Correct me, in case I am wrong)

Prasad · Post by **Prasad** » 23 Feb 2011 09:04

I thought they had the laser warning planned for the initial version itself. I remember coming across a post saying they had this feature in the Mk1 itself from a Def Expo 2004/6 thread. Its planned only for Mk2 then?

Rahul M · Post by **Rahul M** » 23 Feb 2011 09:07

they had tested the LWS on the Mk1 but productionising is a longer process. singha ji is correct that many of the tech have already been tested on Mk1 piecemeal.

suryag · Post by **suryag** » 23 Feb 2011 09:07

how so ? the 2nd 124 Mk1 order is there.

Sirjee wasnt the second order for 124 MK2 ?

Rahul M · Post by **Rahul M** » 23 Feb 2011 09:27

there is a little confusion. from this it appears that the 2nd batch of 124 has some abilities from Mk2, Mk1.5 if you like. the article does say that current production would continue till 2011 end and orders needed to be placed then (at the time of writing the article) for continuity in production line.
http://www.business-standard.com/india/ ... ks/391862/

may be chacko can answer this better.

Singha · Post by **Singha** » 23 Feb 2011 09:44

if the 2nd batch of Mk1.5 has not started production yet, I do not see how they can produce all 124 within 18 months given past production rates.

maybe they will deliver around 60 by then and the rest between june2011 and end 2012...by which time Mk2 ought to be ready for production.

I know its quite a shameful level of production vs the USSR , but thats how we do it....cost/scale etc play a part.

unscientific recollection from discovery channel says a abrams tank from start to finish takes around 8 months to produce on the factory floor. so if one were to use that as a guide, to deliver 60 in 18 months, around 30 tanks need to start in parallel , finish up in 9 months and next lot of 30 take their place.

this kind of tallies with the shopfloor size in pix and video we have seen of the Avadi arjun production area...

chackojoseph · Post by **chackojoseph** » 23 Feb 2011 09:46

30 mins, i will giving you the article on it.

chackojoseph · Post by **chackojoseph** » 23 Feb 2011 10:17

Arjun Tank Production lines may be idle for approx 30 months

Vivek K · Post by **Vivek K** » 23 Feb 2011 10:44

Great! Just what the IA wanted!! Meanwhile the T-90s will pour in!!

abhik · Post by **abhik** » 23 Feb 2011 12:28

Because every few weeks somebody comes up asking why sloped armor is not used in the Arjun and how that makes it inferior etc, i have made two easy to understand explanatory images to show that sloped armor is not all that is made out to be (esp. by discovery channel etc.). Here's a short sloped armor 101 (or rather basic geometry 101)

For the same weight the 'Line of Sight' thickness(and hence the level of protection) will be the same for a slab of both sloped and non sloped armor.

There are only a handful of modern tanks that use significantly sloped armor.

vic · Post by **vic** » 23 Feb 2011 18:05

chackojoseph wrote:Arjun Tank Production lines may be idle for approx 30 months

This is minimum possible delay as Arjun 2 has not been approved as of yet. So 30 months can become 300 months also. But don't worry be happy, we will be weilding the screw driver for Russian assemblies of Tin Can aka T-90

RoyG · Post by **RoyG** » 23 Feb 2011 18:14

30 months...depressing! Ugh, meanwhile more n more inferior tin cans.

SaiK · Post by **SaiK** » 23 Feb 2011 21:56

Couple of approaches -

1. Any common parts for Mk1 and Mk2, they can start manufacturing.

2. Build Mk1 at 1/2 or 1/4th the production rate, and perhaps keep it ready for any possible international sales.

And, get the IA to race on the Arjun Mk2. They can't avoid it.

Vivek K · Post by **Vivek K** » 23 Feb 2011 23:44

The Arjun represents a class of tanks that the Pakis cannot field. It is this type of weapon that India needs to put India out of P{akistan's reach for good!

Rahul M · Post by **Rahul M** » 24 Feb 2011 00:01

thanks chacko. disappointing news all the same.

Prasad · Post by **Prasad** » 24 Feb 2011 00:02

It doesnt make any sense at all. No commercial establishment will be willing to close its production lines for even an hour and we're talking a year plus! Wonder if the CAG can lambast the government over this one.

Surya · Post by **Surya** » 24 Feb 2011 00:23

Can the MP\MLA covering where the factory is located be contacted to raise this in Parliament?

rkhanna · Post by **rkhanna** » 24 Feb 2011 00:37

interesting news

Cross Posting from WAFF

T-90S sole tank to survive grueling Saudi trials

http://newsru.com/world/22feb2011/t90s.html

2 years ago an "undisclosed" Arab country (Saudi Arabia) trialed the T-90, Leo, Leclerc and M1. After a 1300km trek the only tank whose engine didnt fail was the T-90. All other tanks died an awful death and had to be replaced with spare tanks to finish the trials. Uralvagonzavod was the only manufacture that didnt even bring a spare tank to the trials. The T-90 didnt even develop a single oil leak.

In firing trials out to 8km's (3km further than the T-90 max effective range) the T-90 achieved a hit rate of 60%. The Arabs were amazed.

Politics killed the deal with successful Western lobbying forcing the Saudis to shelve the contract. Uralvagonzavod disclosed the results of the Saudi trials only now for the IDEX show.

In response to the above article.. these are the comments of an Ex Tanker. I found it interesting.

1,300km and Western tank cannot survive? I don't believe it
----------------------------------------
u know nothing about tanks. They are not like your cars and are a bietch to maintain. torsion bars snap from just sitting in the parking lot.

driving a tank cross country takes a huge toll on the drive-train/suspension. So it's SOP for driver to dismount on long halts and do a thorough check, Ie all fluids and hull/track inspection. Tracks usually needs to be tightened daily and the whole crew helps. Newer tanks are less maintance whores but still require a lot of time, this is the reason why so many soldiers in armoured regiments prefer to be in a reconnaissance squadron vs a tank squadron (wheeled APCs are easier to maintain = more time to sleep in the field.) Newer tanks are general less likely to break but still will break more than any hummer/APC.

Having a tank break on you is partially based on luck, you can go sometimes 500k without a problem, but more often than not, someone in your troop will go down within 50km. Or your stupid driver can throw a track on the first turn out of the hide.

After how many kms under normal conditions are you supposed to overhaul a western tank?
--------------
We don't overhaul them on a fixed schedule instead we have daily/monthly/semi annually inspections and check-up done on them in garrison, but on an average exercise we can expect to spend 1/5 of our waking hour on nothing but maintance alone.