The Soviet Tank Gamble

[Feanor]

First off the T-90A is 2.2 million. Second off there is only one plant left operating. the UralVagonZavod or UVZ for short. OmskTransMash which produced the T-80U is out of business, and has been sold off. It's repair facilities were bought by our MoD, and the production facilities were bought by UVZ. The Kirov Factory in St. Peters doesn't produce tanks anymore and neither does the Chelyabinsk Traktorniy Zavod (or ChTZ for short).

 

[Tavarisch]

First off the T-90A is 2.2 million. Second off there is only one plant left operating. the UralVagonZavod or UVZ for short. OmskTransMash which produced the T-80U is out of business, and has been sold off. It's repair facilities were bought by our MoD, and the production facilities were bought by UVZ. The Kirov Factory in St. Peters doesn't produce tanks anymore and neither does the Chelyabinsk Traktorniy Zavod (or ChTZ for short).

A few sources say the T-90 (I think without the A suffix intentionally) is at a cost of 1.3 million USD. Maybe this is without the ERA and SHTORA? Or were those estimates? I think those might've been estimates. Correct me if I'm wrong.

What's the annual production of the T-90 anyway?

 

[Feanor]

I don't know what the total annual run is. I know what the annual domestic orders are.

~31 over 2004-5, 31 in 2006, 31 in 2007, 62 in 2008, and allegedly 93 in 2009 (with 93 to be produced in 2010 and 2011 each). When you realize that Indian tanks are still being delivered, along with the Algerian and Cypriot orders, I don't know what it comes out to.

EDIT: I do know there were public statements from UVZ stating that they are able to rapidly raise tank production should the government request it.

 

[Crunchy]

Do they plan to keep the T90 production line while preparing/build a second in the next few years for the new T-xx or will they stop producing the T90 as soon as orders are fullfilled and switch to the new one completely?

 

[Tavarisch]

Do they plan to keep the T90 production line while preparing/build a second in the next few years for the new T-xx or will they stop producing the T90 as soon as orders are fullfilled and switch to the new one completely?

Again, the T-90 is a stop-gap measure. It's going through low-level production. If Russia were to be as economically strong as it were under Soviet times, they'd have replace the entire T-72 fleet by less than 10 years, I think. Soviet tank production ran at about a few thousand a year (not entirely sure of the figure, but I do know it's within the thousands), but from various factories.

 

[FutureTank]

It occurs to me that Soviet designers emphasize somewhat on low-hulls. The principle here is that the tank's low profile should make it harder to hit. But looking back on the previous Gulf Wars, the gamble hasn't paid off. T-72s , T-62s and T-55s still got their turrets blown off jack-in-the-box style, but several other factors play a role here as well.

Soviet designers did not emphasise low hulls. There was a general desire for a compact design that allowed greater concealment and manoeuvrability.
Thats how all tanks explode when the internal ammo detonates...

But think about it, the entire purpose of a low hull is to give it a low-profile right?

No, the purpose is to lower the centre of gravity. Believe it or not, but tanks did roll over during the Second Word War. Also, the curvature of the armour allowed better protection, and this invited lower profile.

On a reverse slope position, the gun depression has to be low. Low profile of Soviet tanks means not being able to depress the gun very far down. This forces the tank to go either slightly forwards on the slope to be able to target enemies from hull-down which in this case negates the low-profile in the first place, or attempt a near-suicidal assault and charge over the slope while the enemy flings 120mm Sabots and TOW missile at you.

This is a myth started with the German tanks by the Allies in the West. There are plethora of reverse slope positions EVERYWHERE in Europe, and globally. Its called ambient terrain undulation. Any undulation below 5m is usually not evident on the topographic military maps, but a tank hull height is about 1.5m. The driver need only ease it up onto the undulation that is usually 1.5-3.5m in height to gain a hull-down position with no need to depress the main gun. To attain a reverse slope firing position as was illustrated in articles and books that supported this view, the tanker first needs to find a convenient height that is a good tactical position, offers a good LOS, and can be accessed over a less than 60 degree slope, because in the illustrations it usually looked like a nice 30-45 degrees slope that looks like a concrete ramp .

Then they have to crawl up it and position themselves in such a way as to make a quick exit to a hide because firing a 105mm or 120mm weapon on top of a hill is VERY visible unless there is a wood or a hill behind the firing tank. THEN the firer has to cope with loosing LOS of the enemy as they manoeuvre on the reverse slope to the next position! Of course all this happens after they have survived the artillery putting down the obligatory harassing fire on top of the ridge "just in case" and have not lost their optics, or have not had their track blown off by a near miss (something US Army only discovered in 1988) in which case they will be busy trying to fix the track on a slope, which is always an interesting exercise that "builds character" as they say

Sure, they could prepare a position on a slope in minutes with the built in dozers for the T-72s (and it's cousins after the T-64). But it probably takes the enemy less time to charge their tanks over that slope while they get things sorted out.

Dig? Who uses tanks to dig? They are for scooping soil ahead of the tank to form a quick berm that will offer additional armour to the tank in an open terrain. A tank round will go through the fresh earth anyway, but the ATGW won't.

This question in turn leads to another one. The low-profile of Soviet tanks has lead to a severe space problem within the tank, which is why some of the ammo is inside the fighting compartment

The ammo is inside the compartment because that is where it has always been. Truth is that if a tank's fighting compartment is penetrated, the crew will not be in any state to make use of the safe ammunition, even if it is untouched. Given this lesson gained over 4 years of armoured warfare there was a widely held belief that the ease of being able to rapidly access the ammunition by all members of the crew is better than having it safe after they are forced to abandon the tank. If this tank is captured, it provides the enemy with a ready supply of ammunition!

Very dangerous, as we have seen in the past few years. (Chechenya, Iraq, Georgia) My suggestion would be to widen the hull to allow a larger auto-loader carousel OR dump the carousel idea completely and use a bustle mounted loader instead, as the Ukrainians have done with their shiny new Oplots. The last thing one wants to do is not have the extra ammo at all, the carousel only has 28 rounds, maybe good for short-term ops but what about those week long ones?

And what if the penetration is in the bustle? Believe me that the turret will achieve free flight in the result

Hopefully, any credible new design that isn't top-secret or based on rumors corrects this principle flaw.

Maybe you would like to go to Tagil and show those engineers how to do it?

Surely enough there is credible evidence as to why this design is still overlooked?

Yes, because there is also a design flaw in the NATO tanks... they are on average 20t heavier! With that sort of weight, the distribution of it is such that you want to put as much of the weight as close to the engine as possible to increase its efficiency. By putting the bustle over the engine, the weight that has to be pushed ahead of the engine is reduced by that weight of the bustle, the ammunition and the surrounding armour, about 10t+. Its the old friction and gravity equation.
Of course to do this, the design requires a very large turret ring, so to portray this as an advantage, the NATO designers claim the NATO tanks are more ergonomic, forgetting that tanks are not made to ensure a comfy ride. You really do not want to be tossed around the turret as the driver tries to frantically take evasive action. In a T-34 tankers would just grab onto the gun, or push against the walls to keep themselves steady. This is why they have those padded helmets which replaced early leather motorcycle helmets seen on very early tank crews who did not realise this aspect of tank driving.
Weigh distribution in general is a problem not just for driving the tank, but also for its automotive components, like the transmission and the gearbox. What people often forget is that having the engine push a 60-70t vehicle up a slope to take up a hull-down firing position is very expensive in fuel, and quite stressful on the transmission. Unlike a family car, the tank's transmission has to be serviced every few hundred hours of operation.
The turret overhang makes assuming some hull down positions dangerous because of the possible need to place the tank in a poor gradient while traversing the slope with the gun pointing to the side because it can place 15% of the tanks' weight outside its hull, and this can cause it to topple on a slope.
.
The bottom line is that every engineering design team tries its best and takes their trade-offs. There are few tanks that are perfect, but if a country can make more of them, so much the better.

 

[Falstaff]

The ammo is inside the compartment because that is where it has always been. Truth is that if a tank's fighting compartment is penetrated, the crew will not be in any state to make use of the safe ammunition, even if it is untouched. Given this lesson gained over 4 years of armoured warfare there was a widely held belief that the ease of being able to rapidly access the ammunition by all members of the crew is better than having it safe after they are forced to abandon the tank. If this tank is captured, it provides the enemy with a ready supply of ammunition!

Without almost any knowledge regarding tanks, I'm just wondering:
Is that so? I was thinking that inside the crew compartment provisions are made to ensure that despite penetration in lets say not so important/vital areas of the tank the crew will be able to fight on, e.g. spall liners and the likes.
I'm thinking of the recent incident when a Fennek in Afghanistan got a door hit by an RPG and the jet crossed the vehicle, blew out the opposite door without much more damage than giving a big shock to the crew.

And what if the penetration is in the bustle? Believe me that the turret will achieve free flight in the result

Isn't that what the blow out panels are for?

Yes, because there is also a design flaw in the NATO tanks... they are on average 20t heavier! With that sort of weight, the distribution of it is such that you want to put as much of the weight as close to the engine as possible to increase its efficiency. By putting the bustle over the engine, the weight that has to be pushed ahead of the engine is reduced by that weight of the bustle, the ammunition and the surrounding armour, about 10t+. Its the old friction and gravity equation.

What's the point of reducing the weight ahead of the engine? This part I don't understand? And what does that have to do with engine efficiency?

As I said, no knowledge, just wondering.

 

[Waylander]

If a tank is penetrated it doesn't automatically mean that the whole crew is incapable to fight on.
With one heavily and one lightly wounded crewmember a 4 men MBT is still able to fight, at least until replacement crews can take over.

And a turret with a seperated ammo compartment is not going to fly.
The energy is going to get blown out of the blowout panels.
And that has been shown to work with the Abrams.

 

[Feanor]

Do they plan to keep the T90 production line while preparing/build a second in the next few years for the new T-xx or will they stop producing the T90 as soon as orders are fullfilled and switch to the new one completely?

Given that they've been promising to show the new tank (presumably Object 195) publicly for years, and have yet to do it, and given that no dates have been given for a serial production run, I suspect that the new tank is a low priority right now. I don't even know if the Object 195 will see a serial production run, or if they will simply use it as the basis for the new MBT concept that they're trying to get a joint-development on with India.

 

[FutureTank]

Without almost any knowledge regarding tanks, I'm just wondering:
Is that so? I was thinking that inside the crew compartment provisions are made to ensure that despite penetration in lets say not so important/vital areas of the tank the crew will be able to fight on, e.g. spall liners and the likes.

I'm thinking of the recent incident when a Fennek in Afghanistan got a door hit by an RPG and the jet crossed the vehicle, blew out the opposite door without much more damage than giving a big shock to the crew.

It is almost impossible to predict the effects of all penetrations, and I was mostly considering a penetration by a tank round rather than an RPG. A dedicated AT missile warhead is also more predictable in how it behaves, but a tank gunner can these days put two rounds in the same spot within seconds.

"a big shock to the crew"? Have you ever had your life flash before your eyes? That's called combat shock. If that crew was able to continue, it would only be because of the extra adrenalin, but different people react in different ways to hits like that. After the adrenalin subsides there is a high probability of depression and mental trauma if not dealt with promptly. These can be just as incapacitating as the physical trauma.

In a current crop of tanks the state of armour is such that the penetrating warhead/round is unlikely to have the force to complete double (through) penetration, and they are designed to do maximum damage on penetration. Spall liners only do so much and are not predictable either due to the variety of ways the penetration can occur. But, of course they help.

Isn't that what the blow out panels are for?

That is the theory, but how that really works in every case is harder to predict. No one sat there exploding hundreds of tank rounds in tens of bustles on a real tank to get a greater statistical model. Its a design principle.
Here is what a blow out panel looks like when it worked http://i.pbase.com/g4/50/673650/2/61666698.S9nZ4BtA.jpg
Here is the top view of another set of panels that worked http://lh5.ggpht.com/_L1AQitLIbd4/RzpO1J2GgYI/AAAAAAAASbs/MvDwtOp0qWo/abrams_20_182.jpg
However on may lighter tanks the turret will fly simply because it lacks the mass to resist the forces created by the ammunition detonation. This is the issue in the design philosophy that seeks a more compact vehicle, or at least a turret. A bustle uses more armour, armour adds weight, weight needs a larger powerplant, larger powerplant needs more fuel, more fuel needs more volume, more volume needs more armour, more armour invites the enemy to design a larger gun, larger enemy gun requires more armour, etc., ad infinitum....potentially
Then there is the top attack like this case http://www.independence05.com/blog/uploaded_images/2006-08MerkavadestroyedinSouthofLebanon-785731.jpg

What's the point of reducing the weight ahead of the engine? This part I don't understand? And what does that have to do with engine efficiency?

Its physics. The engine produces force. It produces enough force to counter those of friction and gravity acting on the tank's mass. The more mass there is in front of the engine, the greater force it requires to propel the mass of the tank when it has to be pushed up an elevation to counter gravity. Consider the trains where the rails are used to eliminate the friction, but when that choo choo is going up-hill, it is struggling to pull the wagons behind itself because of gravity. Sometimes a second engine is attached at the rear to add the push force to the pull force.

In a tank the location of the engine is not purely historical because of the perception of head-on tactical engagements where the winning side wanted to at least salvage the engines if the tank was destroyed because they are expensive to produce. In fact, as can be seen with the Merkava, the engine can be at the front pulling the mass of the tank. The physical forces acting on the tank do not change. What changes is the design philosophy.
A part of that design is the engine maintainability as illustrated here File:AGT1500 engine and M1 tank.JPEG - Wikimedia Commons
However, the further the mass, or any part of it, from the origin of the force, the greater the factor of friction acting on it because of the longer track required to support the mass in a tank. Because the friction is least at the point where the force is applied, the engine well, and because the turret can not be placed on top of the engine, it is placed as close to it as possible. The Soviet philosophy therefore is very conventional in attempting to keep the entire package as compact as possible, producing faster, more manoeuvrable and less logistically dependent designs.

This design philosophy is not based in engineering, but in doctrine. Soviet doctrine was developed over a decade from 1933 as an operational-strategic one in nature, while the Allied (future NATO) doctrine was developed over two years, and is primarily tactical in nature based on the German (Wehrmacht) thinking.

 

[Marc 1]

No, the purpose is to lower the centre of gravity. Believe it or not, but tanks did roll over during the Second Word War. Also, the curvature of the armour allowed better protection, and this invited lower profile.

No, very much a minor consideration. Form follows function - a lower height is desirable because it makes concealment/cover selection easier and make the tank a smaller target. They are not designed to be low so they do not roll over

This is a myth started with the German tanks by the Allies in the West. There are plethora of reverse slope positions EVERYWHERE in Europe, and globally.

No Tavarisch is right. When the older soviet designed vehicles came up to the top of a ridge to a hull down position their guns cannot depress as far as western designs which limits which hills can be used for this type of engagement. It is not a myth.

Then they have to crawl up it and position themselves in such a way as to make a quick exit to a hide because firing a 105mm or 120mm weapon on top of a hill is VERY visible unless there is a wood or a hill behind the firing tank. THEN the firer has to cope with loosing LOS of the enemy as they manoeuvre on the reverse slope to the next position! Of course all this happens after they have survived the artillery putting down the obligatory harassing fire on top of the ridge "just in case" and have not lost their optics, or have not had their track blown off by a near miss (something US Army only discovered in 1988) in which case they will be busy trying to fix the track on a slope, which is always an interesting exercise that "builds character" as they say

Tanks do not operate independently. When one fires and goes to move it does not matter that they have lost LOS, others in the sub unit will be observing and advising. The latest Link 22 type systems will allow unparalleled situational awareness - so this will be a non-issue. I find it hard to believe that the US army only found out in 1988 that tank running gear is vulnerable to artillery fire. It is well known that a 155mm artillery barage can have quite an effect on an armoured vehicles ability to fight - optics, aerials etc are all vulnerable, idlers, roadwheels etc would also be affected that could lead to a tracked vehicle throwing a track.

Dig? Who uses tanks to dig? They are for scooping soil ahead of the tank to form a quick berm that will offer additional armour to the tank in an open terrain. A tank round will go through the fresh earth anyway, but the ATGW won't.

Firstly, semantics. You know what he meant. Secondly, where do you think the berm comes from? From earth scooped out behind the berm. If done correctly in the right soil conditions the tank can effectively have a low berm and be virtually hull down below ground level. Good cover. Sure a tank round will probably go thro6 feet of earth but it will be going a fair bit slower and may even have been deflected.

The ammo is inside the compartment because that is where it has always been.

The latest western tank designs have made advances in crew survivability from surrounding stowed ammunition with water jackets to the use of blow off panels and armoured doors inside the turret bussle to increase crew survivability.

And what if the penetration is in the bustle? Believe me that the turret will achieve free flight in the result

Rubbish, see above.

Yes, because there is also a design flaw in the NATO tanks... they are on average 20t heavier! With that sort of weight, the distribution of it is such that you want to put as much of the weight as close to the engine as possible to increase its efficiency. By putting the bustle over the engine, the weight that has to be pushed ahead of the engine is reduced by that weight of the bustle, the ammunition and the surrounding armour, about 10t+. Its the old friction and gravity equation.

Again, rubbish. Lets go back to basics shall we? The design of an armoured vehicle is a series of trade-offs and compromises. Nearly all western MBT's designed in the last 40 years have been designed around this set of compromises (in no particular order):

1. Needs to be large enough to be habitable for the crew for days at a time shut down in an NBC environment (habitability is a significant issue for soviet designs).

2. Should be well protected - armour means weight.

3. Should be well armed - a 120mm gun requires a large turret to accomodate it and crew (again see habitability) this has lead to a large diameter turret ring.

4. Should have decent mobility (powerful engine/gearbox combination)

5. Must not be too heavy or large in size or transporting the vehicle becomes problematic. It used to be the width of the vehicle was determined y the size of rail tunnels - these days it would possibly be the internal dimensions of an airlifter. Weight will limit strategic and tactical mobility.

How these differing aims were achieved depended on the priorities placed on each design team. The poms decided that armour was the most important consideration when the Chieftan was designed, the French placed emphasis on mobility AMX 30 and the Leopard 1 was possibly the best compromise among this generation of tanks. The next generation the design seemed to settle at a common standard of around 60 to 70 tonnes, 120mm gun, 1000 -1500hp engines. Common requirements tend to produce common designs. The tanks are 20 tonnes too heavy compared to what? Soviet designs?

Of course to do this, the design requires a very large turret ring, so to portray this as an advantage, the NATO designers claim the NATO tanks are more ergonomic, forgetting that tanks are not made to ensure a comfy ride. You really do not want to be tossed around the turret as the driver tries to frantically take evasive action. In a T-34 tankers would just grab onto the gun, or push against the walls to keep themselves steady.

Try that in a modern tank and the stabilisation system will ensure that anyone hanging onto the main armament will be pulped as the gun elevates and depresses. Having riden in a Leopard cross country with stab engaged I was damn glad that there was a big metal guard to keep me from being thrown against the breach as it moved up and down. Its not about 'comfort' as you keep saying - its about trying to minimise crew fatigue levels - warfare is a 24hour business, and particularly during the type of blitzkreig assaults experienced by the armoured forces under Gudarian in 1940 and GW I and GWII, this is a major consideration. In some cases the only times the tankers got to dismount was to reload and refuel for days at a time.

Also its not about steadying yourself whilst the tank scoots to another firing position, crew are not there to hang on for dear life, they will be using their optics, searching for threats/targets, firing the gun whilst on the move and loading the gun. Manhandling a 120mm round in the confines of a turret is difficult enough when stationary - space is not a 'luxury' with current crew numbers and techniques. Sure it is possible to eliminate the loader, but then you have the additional workload of other tasks placed onto the other 3 crew (an argument all by itself).

Weigh distribution in general is a problem not just for driving the tank, but also for its automotive components, like the transmission and the gearbox. What people often forget is that having the engine push a 60-70t vehicle up a slope to take up a hull-down firing position is very expensive in fuel, and quite stressful on the transmission. Unlike a family car, the tank's transmission has to be serviced every few hundred hours of operation.

Your facts to support this? Tank transmissions and drivetrains are perfectly well designed for their task. They are designed to accellerate a 70tonne vehicle up slopes etc. Is this your 20 tonnes overweight hobby horse we are seeing here? The vehicle transmission is designed for its task whether it is a 50kg motoor scooter or a 70 tonne MBT. Fuel, yes it uses quite a bit of fuel to push 70 tonnes up a hill, but I don't think that is a tactical consideration, rather a supply and sustainment issue. Also what is this rubbish about where the weight is located adding to or subtracting from efficiency? Where the weight is has absolutely no bearing in a tracked design beyond the engineering challenge the suspension designers face.

The turret overhang makes assuming some hull down positions dangerous because of the possible need to place the tank in a poor gradient while traversing the slope with the gun pointing to the side because it can place 15% of the tanks' weight outside its hull, and this can cause it to topple on a slope.

Sounds like rubbish to me. If anything a bussle on a turret will help counterbalance the weight of the gun. There are certain limits anyway to using a cross slope as a hull down position - namely the gun depression limits. Normally a tank will approach a crest to achieve a hull down position by driving forward -thickest armour at the front of the vehicle, so cross slope positioning and the risk of the vehicle rolling over is not an issue. Most tracked vehicles by virtue of their design has a much lower centre of gravity than wheeled vehicles - This seems also to be a hobby horse of yours - I haven't seen the internet littered with pictures of MBT's on their lids.
.

The bottom line is that every engineering design team tries its best and takes their trade-offs. There are few tanks that are perfect, but if a country can make more of them, so much the better.

Right...quantity beats quality I do not want to be a digger in any army you are responsible to equip.

 

[FutureTank]

No, very much a minor consideration. Form follows function - a lower height is desirable because it makes concealment/cover selection easier and make the tank a smaller target. They are not designed to be low so they do not roll over

in the case of tanks, form follows doctrine, not function. The T-54 turret came from the JS-3 design concept.
I know it may be hard to believe, but while tanks in combat spend only a fraction of their time in concealment, they spend far more of their time manoeuvring, and they can come to grief more often than one would think when manoeuvring.

No Tavarisch is right. When the older soviet designed vehicles came up to the top of a ridge to a hull down position their guns cannot depress as far as western designs which limits which hills can be used for this type of engagement. It is not a myth.

The Soviet tanks were never designed to "came up to the top of a ridge to a hull down position"! Do you know where the "Western" tactic came from?

Tanks do not operate independently. When one fires and goes to move it does not matter that they have lost LOS, others in the sub unit will be observing and advising. The latest Link 22 type systems will allow unparalleled situational awareness - so this will be a non-issue. I find it hard to believe that the US army only found out in 1988 that tank running gear is vulnerable to artillery fire. It is well known that a 155mm artillery barage can have quite an effect on an armoured vehicles ability to fight - optics, aerials etc are all vulnerable, idlers, roadwheels etc would also be affected that could lead to a tracked vehicle throwing a track.

Please! I know tanks do not operate independently, and so do all tankers! If one tank fires, the assumption those being fired on can make is there is that there are other tanks close to the position from which the fire came from. I do not want to get into semantics, but the crew of a NATO tank in the 60s, 70s and 80s would have been largely focusing on their own fight after loosing LOS. Sure they listen to net, but own visual is an important awareness factor in combat.
Nope, the US Army had to redo its data on artillery effectiveness after someone pointed out the difference between its modelling and that of the Soviet one which reckoned artillery was twice as effective. Turned out the Soviet model was correct.

Firstly, semantics. You know what he meant. Secondly, where do you think the berm comes from? From earth scooped out behind the berm. If done correctly in the right soil conditions the tank can effectively have a low berm and be virtually hull down below ground level. Good cover. Sure a tank round will probably go thro6 feet of earth but it will be going a fair bit slower and may even have been deflected.

I'd know what he meant if he said what he meant.
"If done correctly in the right soil conditions"?
Those attachments on Soviet tanks are not so much for digging. They can create a hasty position that will protect against AT missiles. A 120mm round will go through more than 6feet of piled soil IMHO but I don't have firm figures.

The latest western tank designs have made advances in crew survivability from surrounding stowed ammunition with water jackets to the use of blow off panels and armoured doors inside the turret bussle to increase crew survivability.

Yes, but all that costs in added weight.

I think I have seen one penetration in the bustle from a sabot on an M1 and the turret did not fly off, but that proves very little since there was no ammunition detonation or even cook-off. Maybe that area in the bustle was empty.

Again, rubbish. Lets go back to basics shall we? The design of an armoured vehicle is a series of trade-offs and compromises. Nearly all western MBT's designed in the last 40 years have been designed around this set of compromises (in no particular order):

1. Needs to be large enough to be habitable for the crew for days at a time shut down in an NBC environment (habitability is a significant issue for soviet designs).

2. Should be well protected - armour means weight.

3. Should be well armed - a 120mm gun requires a large turret to accomodate it and crew (again see habitability) this has lead to a large diameter turret ring.

4. Should have decent mobility (powerful engine/gearbox combination)

5. Must not be too heavy or large in size or transporting the vehicle becomes problematic. It used to be the width of the vehicle was determined y the size of rail tunnels - these days it would possibly be the internal dimensions of an airlifter. Weight will limit strategic and tactical mobility.

How these differing aims were achieved depended on the priorities placed on each design team. The poms decided that armour was the most important consideration when the Chieftan was designed, the French placed emphasis on mobility AMX 30 and the Leopard 1 was possibly the best compromise among this generation of tanks. The next generation the design seemed to settle at a common standard of around 60 to 70 tonnes, 120mm gun, 1000 -1500hp engines. Common requirements tend to produce common designs. The tanks are 20 tonnes too heavy compared to what? Soviet designs?

When designing tanks, one starts with simple things like physics, stress and strain, tensions, etc.
"Poms decided that armour was the most important consideration when"....they designed the Centurion. In fact they wanted the heavy tank so much, they designed the trailers to go with them because the largest BA trailer at the time was 40t. The Chieftain was designed based on the British Armoured Corps experience with the Tigers. However, this was based on a flawed understanding of the Soviet doctrine that they Shared with the Americans, and the Germans. The weight of Soviet tanks had nothing to do with it. The AMX 30 and the Leopard I were both designed with specific doctrines in mind, and not weight considerations. They were both replacing the Panther.
The question was raised in therm of Soviet tanks have a flaw, and that flaw is essentially the 20t difference in weight it takes to design a NATO heavy tank due to the very systems you described. I simply addressed this premise.

Try that in a modern tank and the stabilisation system will ensure that anyone hanging onto the main armament will be pulped as the gun elevates and depresses. Having riden in a Leopard cross country with stab engaged I was damn glad that there was a big metal guard to keep me from being thrown against the breach as it moved up and down. Its not about 'comfort' as you keep saying - its about trying to minimise crew fatigue levels - warfare is a 24hour business, and particularly during the type of blitzkreig assaults experienced by the armoured forces under Gudarian in 1940 and GW I and GWII, this is a major consideration. In some cases the only times the tankers got to dismount was to reload and refuel for days at a time.

However, we are not discussing modern tanks.

Also its not about steadying yourself whilst the tank scoots to another firing position, crew are not there to hang on for dear life, they will be using their optics, searching for threats/targets, firing the gun whilst on the move and loading the gun. Manhandling a 120mm round in the confines of a turret is difficult enough when stationary - space is not a 'luxury' with current crew numbers and techniques. Sure it is possible to eliminate the loader, but then you have the additional workload of other tasks placed onto the other 3 crew (an argument all by itself).

There used to be a five man crew in a 120mm armed US Tank.

Your facts to support this? Tank transmissions and drivetrains are perfectly well designed for their task. They are designed to accellerate a 70tonne vehicle up slopes etc. Is this your 20 tonnes overweight hobby horse we are seeing here? The vehicle transmission is designed for its task whether it is a 50kg motoor scooter or a 70 tonne MBT. Fuel, yes it uses quite a bit of fuel to push 70 tonnes up a hill, but I don't think that is a tactical consideration, rather a supply and sustainment issue. Also what is this rubbish about where the weight is located adding to or subtracting from efficiency? Where the weight is has absolutely no bearing in a tracked design beyond the engineering challenge the suspension designers face.

There is quite a bit of difference in designing automotive parts in a 60t tank to a motor scooter.

Sounds like rubbish to me. If anything a bussle on a turret will help counterbalance the weight of the gun. There are certain limits anyway to using a cross slope as a hull down position - namely the gun depression limits. Normally a tank will approach a crest to achieve a hull down position by driving forward -thickest armour at the front of the vehicle, so cross slope positioning and the risk of the vehicle rolling over is not an issue. Most tracked vehicles by virtue of their design has a much lower centre of gravity than wheeled vehicles - This seems also to be a hobby horse of yours - I haven't seen the internet littered with pictures of MBT's on their lids.

Yes, it all sounds like rubbish, but the bustle has no counterbalancing role in the design. It will prove dangerous however in certain firing positions in some designs.
"Normally a tank will approach a crest to achieve a hull down position by driving forward -thickest armour at the front of the vehicle" - and why would the tank commander do that?
There area few pictures of MBTs on their lids, but there have not been all that many MBTs in tank-vs-tank combat, and when they are there is little time to take pictures.
I don't have hobby horses.

Right...quantity beats quality I do not want to be a digger in any army you are responsible to equip.

Well, its about time you leaned that

la fortune est toujours, comme disait le pauvre M. de Turenne, pour les gros bataillons, fortune is always, as poor Mr. de Turenne used to say, for the big battalions.

Cf. [1673 Mme de Sévigné Letter 22 Dec.]
Ultimately the numerically inferior but more sophisticated force will find itself in attrition warfare where the sophistication gap had been reduced. That's why there was an Armistice in Korea, and NATO never attacked the Warsaw Pact. I can go on with examples...

 

[Falstaff]

Its physics. The engine produces force. It produces enough force to counter those of friction and gravity acting on the tank's mass. The more mass there is in front of the engine, the greater force it requires to propel the mass of the tank when it has to be pushed up an elevation to counter gravity. Consider the trains where the rails are used to eliminate the friction, but when that choo choo is going up-hill, it is struggling to pull the wagons behind itself because of gravity. Sometimes a second engine is attached at the rear to add the push force to the pull force.

(...)

However, the further the mass, or any part of it, from the origin of the force, the greater the factor of friction acting on it because of the longer track required to support the mass in a tank. Because the friction is least at the point where the force is applied, the engine well, and because the turret can not be placed on top of the engine, it is placed as close to it as possible. The Soviet philosophy therefore is very conventional in attempting to keep the entire package as compact as possible, producing faster, more manoeuvrable and less logistically dependent designs.

Excuse me, but physically this is highly incorrect. An engine produces torque, not force. This torque is then transmitted through the drive train to the drive sprocket, where we have a transformation from torque to force via lever. This is where the force is applied. It is then transmitted further through the tracks, which we can think of as a belt transmission, to the ground where it interacts to propel the vehicle.
The efficiency of the engine is an inherent characteristic of its design, the efficiency of the drive train (to the drive sprocket) however is largely dependant on how "long" (figuratively) the drive train is. Yes, there is friction, among other things like torsion and slip. That's why the drive sprocket is in the rear, when the engine is in the rear, or in the front, when the engine is in the front.
This has nothing to do with the distribution of weight. You can place the engine wherever you want, it doesn't matter for its efficiency. It matters for the efficiency of the drive train though, but again, not because of weight distribution.
Considering the tracks I'm pretty much sure that an even weight distribution is the ideal situation for maximum efficiency.

The train example you chose is a bad one, for several reasons, as first of all in the configuration you mentioned the reason a push configuration can climb steeper hills than a pull configuration has to do with the shift of the center of gravity towards the engine and the fact that a railroad engine has wheels. I won't explain that now, for my (and the other readers') convenience.

Besides that I was under the impression that the bustle is located where it is just because it is best protected there in head-to-head engagements. Would be rather silly to place it in front of the turret, eh

 

[Marc 1]

in the case of tanks, form follows doctrine, not function. The T-54 turret came from the JS-3 design concept.
I know it may be hard to believe, but while tanks in combat spend only a fraction of their time in concealment, they spend far more of their time manoeuvring, and they can come to grief more often than one would think when manoeuvring.

Semantics again. And doctrine determines function which influences form. Why is it in any way relevant to the conversation that the T54's turret came from the JS 3 concept? Sprinking book facts through your text does little to aid your credibility. Back on topic, tanks do in fact spend great gobs of their time stationary which is why the fuel consumption of the M1's gas turbine was such an issue. Whilst I have never been to a two way rifle range I have exercised often with 1 Armd - and apart from a Leopard stuck fast in a really soft piece of ground ,have yet to see one 'come to grief' let alone roll over (which was you earlier assertation that you seem to be backing away from).

The Soviet tanks were never designed to "came up to the top of a ridge to a hull down position"! Do you know where the "Western" tactic came from?

No, they weren't designed that way because the soviet doctrine emphasized offensive manouvre warfare. But as we all know warfare doesn't always go according to plan and the advantages in designing an MBT with good mobility and a low silhouette turn into disadvantages when the MBT is used in say the defence. The western designs are more adaptable to other types of warfare.

I don't know where the Western tactic came from or what it is, but I have been trained to employ tanks in offensive and defensive operations.

Please! I know tanks do not operate independently, and so do all tankers! If one tank fires, the assumption those being fired on can make is there is that there are other tanks close to the position from which the fire came from. I do not want to get into semantics, but the crew of a NATO tank in the 60s, 70s and 80s would have been largely focusing on their own fight after loosing LOS. Sure they listen to net, but own visual is an important awareness factor in combat.
Nope, the US Army had to redo its data on artillery effectiveness after someone pointed out the difference between its modelling and that of the Soviet one which reckoned artillery was twice as effective. Turned out the Soviet model was correct.

Oh right so it wasn't: "(something US Army only discovered in 1988)" The US army knew about the possibility of a mobility kill with artillery before 1988 except that they had underestimated it effectiveness. So what? Artillery was still going to be used against armoured formations if for no other reason that it keeps the crews buttoned down and buggers up their situational awareness. Employing 155's against armour was something I was taught in 1987. To paraphrase you, I'd have known what you meant if you had said what you really meant.

I'd know what he meant if he said what he meant.

Just a guess, english is his second language - and he does pretty damn well if you ask me. I worked out what he meant, you wanted to nit pick.

"If done correctly in the right soil conditions"?

Yeah - kinda hard to dig yourself through say a granite shelf.

Those attachments on Soviet tanks are not so much for digging. They can create a hasty position that will protect against AT missiles. A 120mm round will go through more than 6feet of piled soil IMHO but I don't have firm figures.

So being hull down is no advantage?

Yes, but all that costs in added weight.

So you don't think the added weight of crew survivability features such as water jackets around ammunition stowage, and armoured door/blowoff panels is a good idea... Strange that you have so little regard for crew - highly trained crew are irreplacable which is why nations that value the experience and lives of their crew have designed tanks like the Merkava.

I think I have seen one penetration in the bustle from a sabot on an M1 and the turret did not fly off, but that proves very little since there was no ammunition detonation or even cook-off. Maybe that area in the bustle was empty.

Seems to fly in the face of what you said before about any hit to the bussle resulting in a flying turret.

When designing tanks, one starts with simple things like physics, stress and strain, tensions, etc.

Seriously? You don't think they had to examine the basic ideas -the big three - firepower,protection and mobility first? When you reach decisions on the first three then it becomes an engineering issue of stresses, grades of steel and construction methodologies. This continual insistence of rebuttal for the sake of substituting words really only annoys people Future Tank. My original point was that tanks have evolved the way they have due to the tradeoffs that were made for each design. The soviets compromise in their designs meant their MBTs were comparitively light, fairly well protected, well armed and with a excellent mobility, but the cramped/poorly insulated working conditions for the crew mean that fatigue is a definate issue as is the problem of main gun depression. The Indian Army has found that the internal temps are playing havoc with electronic equipment, and that retrofitting anything inside the turret is difficult due to the lack of space.

"Poms decided that armour was the most important consideration when"....they designed the Centurion. In fact they wanted the heavy tank so much, they designed the trailers to go with them because the largest BA trailer at the time was 40t. The Chieftain was designed based on the British Armoured Corps experience with the Tigers. However, this was based on a flawed understanding of the Soviet doctrine that they Shared with the Americans, and the Germans.

The poms have had a history of heavy 'infantry tanks stretching back to the Matilda, Churchill, Centurion. They did not need to copy the experiemce with the Tigers. What flawed understanding of soviet doctrine? The western cold war tanks were basically designed to counter a massed invasion of soviet tanks, thus mobility, especially for the pommy designs was accorded a lower priority than protection and firepower (the 120mm was then the largest fitted to a NATO tank).

The weight of Soviet tanks had nothing to do with it.

The AMX 30 and the Leopard I were both designed with specific doctrines in mind, and not weight considerations. They were both replacing the Panther.
The question was raised in therm of Soviet tanks have a flaw, and that flaw is essentially the 20t difference in weight it takes to design a NATO heavy tank due to the very systems you described. I simply addressed this premise.

You are waffling here. Why is it a flaw to have a tank that weighs 20t more than the soviets? We have just gone over why the tanks have turned out the way they have. It's like saying that a Toyota Landcruiser is a flawed design because it weighs 1 tonne more than a Suzuki Jimny. The vehicles are different sizes - of course there will be different weights.

However, we are not discussing modern tanks.

Really? From the first post in this thread, first, second and third lines:

"It occurs to me that Soviet designers emphasize somewhat on low-hulls. The principle here is that the tank's low profile should make it harder to hit. But looking back on the previous Gulf Wars, the gamble hasn't paid off. T-72s , T-62s..."

I didn't know that T72's were WWII designs... Must have just scraped into the Battle of Berlin.

There used to be a five man crew in a 120mm armed US Tank.

And a crew of 18 in a German A7V. But that is irrelevant to this discussion.

There is quite a bit of difference in designing automotive parts in a 60t tank to a motor scooter.

But the principles are the same. You missed the point entirely. The engineer looks at the parameters and produces a transmission to meet the requirements. The soviet designers would have designed and selected their transmission with the weight class of vehicle in mind, the same as the western designers. The point was the transmission is designed to do the job regardless of it being designed for a motor scooter or MBT. Inferring that one will be stressed to a higher level to support your assertation that western tanks are overweight is wrong.

Yes, it all sounds like rubbish, but the bustle has no counterbalancing role in the design. It will prove dangerous however in certain firing positions in some designs.

So, let me get this straight, gun out the front, but adding weight overhanging the turret at the back is going to have no counterbalancing effect? What drugs are you on? The only hazard that a bustle or any overhang for that matter brings is to act as a shot trap - ie deflecting the incoming round in toward the turret ring. What threat were you referring to?

"Normally a tank will approach a crest to achieve a hull down position by driving forward -thickest armour at the front of the vehicle" - and why would the tank commander do that?

Are you serious or do you just like typing for the sake of it? Gee, thickest armour toward the most likely threat - why would a tank commander do that? Obviously you have not seen the way armour moves in bounds - they will nose up to a hull down firing position, then when given the word to move, will reverse into the dead ground (never straight over the top), then move forward at a different (usually lower)point of the ridge. The same technique for retreating in bounds.

There area few pictures of MBTs on their lids, but there have not been all that many MBTs in tank-vs-tank combat, and when they are there is little time to take pictures.

So if there isn't time to take pictures there must be heaps of after action reports about tanks that have just rolled wouldn't there? Tanks are used for training too - often times quite realistic training - yet I still don't see great numbers of tracked vehicles that have rolled onto their sides. About the only photos you will find in any numbers are shots of M113's that have gone end over end due to the driver grabbing the pivots too damn hard or at too high a speed. Again that is a specific well known issue relating to how that vehicle is operated and has little to do with the relative height of the Centre Of Gravity

I don't have hobby horses.

You could be right here - just the inability to admit when you are wrong, which, because you are still arguing the same dead point, just makes it look like you have certain agendas.

Well, its about time you leaned that Cf. [1673 Mme de Sévigné Letter 22 Dec.]
Ultimately the numerically inferior but more sophisticated force will find itself in attrition warfare where the sophistication gap had been reduced. That's why there was an Armistice in Korea, and NATO never attacked the Warsaw Pact. I can go on with examples...

Did you forget that the septics were at a massive numerical inferiority in the Gulf War? They seemed to win pretty decisively there. Past 'losses' such as Vietnam were not lost because the yanks had superior technology rather than superior numbers that battle was lost because the politicians bottled out.

 

[FutureTank]

Excuse me, but physically this is highly incorrect. An engine produces torque, not force. This torque is then transmitted through the drive train to the drive sprocket, where we have a transformation from torque to force via lever. This is where the force is applied. It is then transmitted further through the tracks, which we can think of as a belt transmission, to the ground where it interacts to propel the vehicle.
The efficiency of the engine is an inherent characteristic of its design, the efficiency of the drive train (to the drive sprocket) however is largely dependant on how "long" (figuratively) the drive train is. Yes, there is friction, among other things like torsion and slip. That's why the drive sprocket is in the rear, when the engine is in the rear, or in the front, when the engine is in the front.
This has nothing to do with the distribution of weight. You can place the engine wherever you want, it doesn't matter for its efficiency. It matters for the efficiency of the drive train though, but again, not because of weight distribution.
Considering the tracks I'm pretty much sure that an even weight distribution is the ideal situation for maximum efficiency.

The train example you chose is a bad one, for several reasons, as first of all in the configuration you mentioned the reason a pull configuration can climb steeper hills than a pull configuration has to do with the shift of the center of gravity towards the engine and the fact that a railroad engine has wheels. I won't explain that now, for my (and the other readers') convenience.

Besides that I was under the impression that the bustle is located where it is just because it is best protected there in head-to-head engagements. Would be rather silly to place it in front of the turret, eh

I didn't go into the greater engineering detail as I didn't think it was necessary, and I agree that he train was not a good example. However, it seems to me that locating the engine as close to the centre of gravity of the vehicle as possible significantly aids design efficiency. I even remember an article on it somewhere a few years ago (though not specific to tanks).

 

[Falstaff]

I didn't go into the greater engineering detail as I didn't think it was necessary, and I agree that he train was not a good example. However, it seems to me that locating the engine as close to the centre of gravity of the vehicle as possible significantly aids design efficiency. I even remember an article on it somewhere a few years ago (though not specific to tanks).

The sense of placing as much mass as possible towards the center of gravity wrt motorized vehicles is that this reduces the moment of inertia when turning. See e.g. sports cars with a mid-engine. And in cars it certainly helps to gain an even weight distribution, if you shift the heavy compact mass of the engine towards the middle.
So in tanks the sense perhaps lies in improved mobility, but certainly not in propulsion efficency. I don't know however if the placement of a tank engine (as the rest of the tank is pretty heavy compared to the engine, other than in cars) makes that much of a difference there.

 

[FutureTank]

The sense of placing as much mass as possible towards the center of gravity wrt motorized vehicles is that this reduces the moment of inertia when turning. See e.g. sports cars with a mid-engine. And in cars it certainly helps to gain an even weight distribution, if you shift the heavy compact mass of the engine towards the middle.
So in tanks the sense perhaps lies in improved mobility, but certainly not in propulsion efficency. I don't know however if the placement of a tank engine (as the rest of the tank is pretty heavy compared to the engine, other than in cars) makes that much of a difference there.

You are right, but it did make a difference once in tank design history. Remember the BTs based on Christy's ideas? The fast tank never really left the heads of Soviet designers even in the 80s, and the T-90 is a testament to this in a way though it is not a new design.
This has been largely lost from Western AFV design thinking, except maybe in the light tracked types.
However, this "need for speed" was still a dominant factor in Soviet tank design through the 80s based on the tempo they set to the offensives. Also, not sure how widely you read, but in many Soviet armour tactical publications they emphasise tactical manoeuvre, as in by individual tanks taking as much advantage from topography, to reinforce the idea of driving in a highly aggressive manner. Every Soviet tank memoir emphasises this manner of driving. Naturally what suffers most is the torsion bar.
I will try to find that article on the vehicle's centre of gravity relationship to overall design.

 

[Marc 1]

You are right, but it did make a difference once in tank design history. Remember the BTs based on Christy's ideas? The fast tank never really left the heads of Soviet designers even in the 80s, and the T-90 is a testament to this in a way though it is not a new design.
This has been largely lost from Western AFV design thinking, except maybe in the light tracked types.
However, this "need for speed" was still a dominant factor in Soviet tank design through the 80s based on the tempo they set to the offensives. Also, not sure how widely you read, but in many Soviet armour tactical publications they emphasise tactical manoeuvre, as in by individual tanks taking as much advantage from topography, to reinforce the idea of driving in a highly aggressive manner. Every Soviet tank memoir emphasises this manner of driving. Naturally what suffers most is the torsion bar.
I will try to find that article on the vehicle's centre of gravity relationship to overall design.

The Christie tank and BT series had their engine in the rear, turret in the centre and driver at the front - much lke current designs. How does this wash with your assertation that the mass needs to be centralised? One of the fastest tracked vehicles in recent service would be the brits Scimitar/Scorpion varients. Official top speed 80kph, unofficially, quite a bit more - they are front engined.

 

[Abraham Gubler]

The Christie tank and BT series had their engine in the rear, turret in the centre and driver at the front - much lke current designs. How does this wash with your assertation that the mass needs to be centralised? One of the fastest tracked vehicles in recent service would be the brits Scimitar/Scorpion varients. Official top speed 80kph, unofficially, quite a bit more - they are front engined.

Welcome to the world of FutureTank... he's ideas are to military science as Scientology is to psychology.

Compartmentalised ammunition in a turret bustle, forward mounted engines, etc does not mean the tank's centre of gravity is somehow upset if it is designed in from start. The Abrams was designed to have the weight of its ammunition in the turret bustle. The Merkava was designed to have the engine in the front. Both Abrams and Merkava are neither front or rear loaded but have perfectly normal centres of gravity (ie in the centre).

Also the density of tank gun ammunition is actually quite low compared to armour, suspension, engines, etc. in a tank. Chemical propellant inherently has an oxidizer leading to quite low density. Only someone completely ignorant of basic engineering principles would assert that these design features inherently lead to a tank being 'unbalanced' and somehow unable to drive fast.

The idea that tactical and operational speed has been lost from 'western' tank design a crazy assertion. The FCS vehicles are designed to be the fastest tank in a tactical, operational and strategic sense ever seen on any battlefield. Abrams, Leopard 2, etc all designed for high speed. Even the much mobility maligned Merkava 1/2/3 were designed for high sustained speed cross country (more a function of suspension travel than power to weight) as Israel's operational theatres lacked road infrastructure (Golan, Sinai).

 

[FutureTank]

Semantics again. And doctrine determines function which influences form. Why is it in any way relevant to the conversation that the T54's turret came from the JS 3 concept? Sprinking book facts through your text does little to aid your credibility. Back on topic, tanks do in fact spend great gobs of their time stationary which is why the fuel consumption of the M1's gas turbine was such an issue. Whilst I have never been to a two way rifle range I have exercised often with 1 Armd - and apart from a Leopard stuck fast in a really soft piece of ground ,have yet to see one 'come to grief' let alone roll over (which was you earlier assertion that you seem to be backing away from).

The suggestion is that the Soviet designs do not care about crew survival. However, the design of T-34 clearly was superior in ensuring crew survival because it prevented penetration of armour in a better way.
The design of the JS-3 turret further enhanced this crew protection with the then available technology and design philosophies.
Maybe M1s spent a great deal of time stationary in combat, but not Soviet tanks, by and large. Keep looking and you will find such photos from many different armed forces posted online. Just today I was reading that in the very first batch of M26s deployed to Europe, one collapsed a bridge and tumbled into the river below. I have seen pictures of USMC M1 on its top, and a similar one for a Merkava. Stuff like that happens, though maybe not often now days, and not in Australia. In combat it happened far more often

No, they weren't designed that way because the soviet doctrine emphasised offensive manoeuvre warfare.

Care to share why you think the Soviet tanks follow that 'flawed' design philosophy?

But as we all know warfare doesn't always go according to plan and the advantages in designing an MBT with good mobility and a low silhouette turn into disadvantages when the MBT is used in say the defence.

Oh really? You don't suppose German tank destroyers were any good in defence during the Second World War?

The western designs are more adaptable to other types of warfare.

I don't want to be again accused of semantics, so did you really mean 'warfare', or tactical and operational postures?

I don't know where the Western tactic came from or what it is, but I have been trained to employ tanks in offensive and defensive operations.

Yes, but you never served in Europe, did you?

Oh right so it wasn't: "(something US Army only discovered in 1988)" The US army knew about the possibility of a mobility kill with artillery before 1988 except that they had underestimated it effectiveness. So what? Artillery was still going to be used against armoured formations if for no other reason that it keeps the crews buttoned down and buggers up their situational awareness. Employing 155's against armour was something I was taught in 1987. To paraphrase you, I'd have known what you meant if you had said what you really meant.

No, the US Army grossly underestimated the effectiveness of their own and Soviet Artillery for 40 years after the Second World War. This means that they battery would be firing twice as much ground burst HE rather than air burst to keep the tank commanders' heads down. Not that it matters since given the Soviets did understand the true effectiveness of the artillery, they would take measures not to encounter it. However, here again we have the supposed flaw in Soviet tank design, although it is the larger NATO tanks that would, statistically speaking, be more exposed to damage and therefore enforced crew dismounting due to being larger.
I hasten to remind you that the M1, Challenger and Leopard II all appeared after 1984 in any significant numbers in Europe. Their predecessors were not particularly superior in terms of crew survival to the Soviet models. They all took two decades do get from concept to field in which time Soviets deployed not only two generations of tanks, but two competitive models in one generation, introducing autoloaders and functional gun-launched AT missiles.

Just a guess, english is his second language - and he does pretty damn well if you ask me. I worked out what he meant, you wanted to nit pick.

Ok, I didn't realise that, so my appologies.

Yeah - kinda hard to dig yourself through say a granite shelf.

"If done correctly in the right soil conditions"? - no, seriously, you expect someone to jump out and start doing soil testing?

So being hull down is no advantage?

Its not a "hull down" position, but a temporary anti-missile scrape. Believe it or not, the Soviet tankers also train to assume hull down positions. Its not like the European terrain is completely devoid of spots where a Soviet tank does not need to expose itself too much to fire. Nor is the terrain prevalent to allow ubiquitous hull down positions for NATO tanks. All crews are trained to look for most suitable positions.

So you don't think the added weight of crew survivability features such as water jackets around ammunition stowage, and armoured door/blowoff panels is a good idea... Strange that you have so little regard for crew - highly trained crew are irreplacable which is why nations that value the experience and lives of their crew have designed tanks like the Merkava.

I didn't say I think these crew survival measures are a bad idea. What I say is that their lack in Soviet tanks is not a design flaw. Even in the Merkava the crew survival philosophy was only brought home by the 1973 war, and was not implemented until 1979 I think, three years after T-80 entered production.

Seems to fly in the face of what you said before about any hit to the bussle resulting in a flying turret.

Maybe that was an overly spurious comment to make given lack of statistical evidence. However, based on bustle detonation, even with the blow out panels I think the turret fighting compartment would not be unaffected, which is what most people seem to assume.
That is however the least of the crew's problem. In the case of the M1 SEP, the surviving crew will be left in the midst of combat with, perhaps, six rounds in the hull. I suppose you know how long those last...

Seriously? You don't think they had to examine the basic ideas -the big three - firepower,protection and mobility first?

Nope. Firepower and protection are both matters of physics. Mobility was determined by the norms guided by doctrine in the Soviet Army that was the design bureaus' sole client. Organisational velocity if you will. What was considered though which was not a matter of science, was the industrial production capacity for a new design. That is where the T-64 came a cropper. The other 'big one' is of course the crews you keep talking about. The Soviet Army found that they just could not allocate enough conscripts to crew the more complex designs in the offing in the 60s, so they reduced the crew and increased the support personnel numbers. I can't remember who, but someone worked out that if the essential field support personnel are added to the tank's crew, then a Soviet 3-crew tank has a crew of 5, while the then new NATO tanks had crews of 7-8. And this just happens to describe the factors that Soviets think are important in considering a tank design, the 'big five': suitability for production, ease of crew and support personnel training, and combat characteristics you mentioned. Again there is no flaw because the Soviet Union was outproducing NATO in tanks, and because NATO designers were attempting to design catch-up models for two decades. Again, no flaw.

When you reach decisions on the first three then it becomes an engineering issue of stresses, grades of steel and construction methodologies. This continual insistence of rebuttal for the sake of substituting words really only annoys people Future Tank. My original point was that tanks have evolved the way they have due to the tradeoffs that were made for each design. The soviets compromise in their designs meant their MBTs were comparitively light, fairly well protected, well armed and with a excellent mobility, but the cramped/poorly insulated working conditions for the crew mean that fatigue is a definate issue as is the problem of main gun depression.

But I'm not rebutting. In what way did the Soviets compromise their designs? That they were "cramped/poorly insulated working conditions"? As I understand it the T-54 was a comparative limousine tot he T-34/85, never mind the 76mm armed model. Sure the Americans went from crewing medium M4s to heavy M26s and their M46 redesigns. I suspect that had the Soviet Army chosen to adopt the JS-3 as their point of MBT design origin they too would have had the volume to introduce all sorts of creature comforts. Are you saying that doing more with less in tank warfare is a flaw?
When people start comparing "apples with apples", I will happily listen.

The Indian Army has found that the internal temps are playing havoc with electronic equipment, and that retrofitting anything inside the turret is difficult due to the lack of space.

Which electronic equipment? You mean this?

Confirming the Jane's report, senior Army officers told this newspaper that the French Catherine thermal imaging (TI) camera, which gives the T-90's Belarussian (Peling IG-46) night sight its 3 km range and higher accuracy, is not "adequately tropicalised" and hence prone to malfunctioning in the extreme heat of the Rajasthan desert region, where temperatures inside the MBT routinely average between 55ºC and 60ºC.

Is it a flaw in the Soviet design that the French electronics don't function in Indian deserts?
Here India Army´s T-72 Upgrade Program - Project RHINO [Archive] - Military Photos is an article on the T-72 Indian upgrade planning c.2004. So you take a state-designed tank that had state enterprises design upgrade systems and subsytems for, and you try and fit systems and subsystems designed by non-state commercial enterprises that never intended their product to go into the T-72. What were those Soviet designers thinking of?
Where is the flaw in design here?