MBT Survivability Comparison Thread

[arnabmit]

Of the different MBTs in operation today across the world, I would like to invite you to discuss which parts of which MBT is better purely in terms of suitability.

Let's discuss on the following parameters:

• Turret shape
• Hull shape
• Top attack protection
• Composite armor
• Reactive armor
• Engine protection
• Ammo container protection
• Hard/Soft kill protection suites

@Kunal Biswas @ersakthivel @Damian @Dejawolf & others...

 

[Damian]

In terms of crew survivability, M1 is still unmatched by any other tank design (excluding some technology demonstrators and prototypes).

Other characteristics of all Main Battle Tanks are more or less comparable.

 

[bose]

Can anyone explain how the tank's turret design contribute to its protection ? in the context of debate of having a un manned turret with auto loader... Is un manned turret a silver buttet as percieved by many ??

 

[Damian]

Turret design during classic type of egnagement needs to provide protection within 60 degrees frontal arc because this is from where, majority of hit will came.

On the other hand this makes turret rather heavy and large, thus increasing vehicle weight.

Unmanned turret does not need to protect crew, because crew sits in it's own compartment inside hull.

Hull is much lower, thus easier to hide and more difficult to hit, especially over a larger distance. So unmanned turret can have a minimal required size to hold main gun, autoloader mechanisms, stabilization system and servomechanisms as well as sighting system components.

So for example if manned turret of most modern tanks on avarage weights around 25-30 tons, unmanned turret can for example weight 10 tons or even less.

If nececary unmanned turret can of course be uparmored by use of modular armor system.

In such situation we can achieve two things.

First is reduction of vehicle weight in it's basic configuration.

Second, if we wish to keep vehicle current weight, we can use saved weight limit to improve hull protection. In such scenario if we have two tanks, one with manned turret and one with unmanned turret, both weighting 60 tons, design with unmanned turret will have a much higher degree of protection.

So in the end, unmanned turret is the only rational solution.

Also unmanned turret can be designed as quickly replacable module, which means that for example on the same hull, we can place a tank turret or different kind of turret weapon system, be it similiar turret system as in Russian BMPT, or for example a gun-howitzer turret module or gun-mortar turret module, or anti-aircraft defence turret module.

 

[arnabmit]

I was thinking of something else... Not as a MBT as a whole, but compare each part individually.

Eg: The turret shape and design of Merkava-IV, M1 Abrams, Leo 2. Which design would be more survivable? Similar for the other parameters.

In terms of crew survivability, M1 is still unmatched by any other tank design (excluding some technology demonstrators and prototypes).

Other characteristics of all Main Battle Tanks are more or less comparable.

 

[Kunal Biswas]

IMHO, Western design tanks are much safer to operate than Eastern ( Russian ) design tanks ..

For example T-72/80/90 use auto-loader this cause it to be lighter and lesser crew but in exchange the ammo is exposed inside the crew compartment, When there is a penetration and fire inside the turret the ammo catches fire and tank get destroyed ..


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Where as Arjun MK2 comes with contanariesd ammo With blow off panel, If there is a penetration in the turret and fire the ammo is safely located in ammunition bin hence no explosion, In the hull extra ammo are also kept which are too sealed in individual compartments reducing chances of explosion at instant, tank also comes with its own auto fire suppression system..


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Western tanks and Arjun are heavy compare to eastern tanks but they are more easy to operate over muddy and sandy areas due to lower ground pressure due to there wide tracks, where as lighter eastern tanks have higher ground pressure due to narrow tracks ..

 

[Kunal Biswas]

Unmanned turret is indeed a big achievement but again there are question can it function after getting wet inside a river, Extreme humid conditions etc..

Can anyone explain how the tank's turret design contribute to its protection ? in the context of debate of having a un manned turret with auto loader... Is un manned turret a silver buttet as percieved by many ??

 

[Damian]

Unmanned turret is indeed a big achievement but again there are question can it function after getting wet inside a river, Extreme humid conditions etc..

Unmanned turret can work in such conditions if designed to do so. If not then this is just designing team shortsighting.

 

[bose]

IMHO, Western design tanks are much safer to operate than Eastern ( Russian ) design tanks ..

For example T-72/80/90 use auto-loader this cause it to be lighter and lesser crew but in exchange the ammo is exposed inside the crew compartment, When there is a penetration and fire inside the turret the ammo catches fire and tank get destroyed ..


=====================

Where as Arjun MK2 comes with contanariesd ammo With blow off panel, If there is a penetration in the turret and fire the ammo is safely located in ammunition bin hence no explosion, In the hull extra ammo are also kept which are too sealed in individual compartments reducing chances of explosion at instant, tank also comes with its own auto fire suppression system..


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Western tanks and Arjun are heavy compare to eastern tanks but they are more easy to operate over muddy and sandy areas due to lower ground pressure due to there wide tracks, where as lighter eastern tanks have higher ground pressure due to narrow tracks ..

Basically there is difference of perception between the Western & Soviet Tank designers, based on their socio – political thinking in these two blocks of countries and the same had profound effect on their Tank design too. The Soviets with their world war – II experience of throwing in quantity were less concerned about their crew safety and ability to accept human loss in large numbers, while the western countries took an opposite route with more emphasis on crew safety as they are more sensitive to human loss.

 

[Damian]

You are making wrong conclussions.

Soviets during Cold War were also thinking about greater crew survivability, however none of these ideas were bring beyond prototype stage due to different reasons.

Also, besides M1, all other NATO tanks, have very similiar crew survivability like Soviet tanks.

 

[bose]

Turret design during classic type of egnagement needs to provide protection within 60 degrees frontal arc because this is from where, majority of hit will came.

On the other hand this makes turret rather heavy and large, thus increasing vehicle weight.

Unmanned turret does not need to protect crew, because crew sits in it's own compartment inside hull.

Hull is much lower, thus easier to hide and more difficult to hit, especially over a larger distance. So unmanned turret can have a minimal required size to hold main gun, autoloader mechanisms, stabilization system and servomechanisms as well as sighting system components.

So for example if manned turret of most modern tanks on avarage weights around 25-30 tons, unmanned turret can for example weight 10 tons or even less.

If nececary unmanned turret can of course be uparmored by use of modular armor system.

In such situation we can achieve two things.

First is reduction of vehicle weight in it's basic configuration.

Second, if we wish to keep vehicle current weight, we can use saved weight limit to improve hull protection. In such scenario if we have two tanks, one with manned turret and one with unmanned turret, both weighting 60 tons, design with unmanned turret will have a much higher degree of protection.

So in the end, unmanned turret is the only rational solution.

Also unmanned turret can be designed as quickly replacable module, which means that for example on the same hull, we can place a tank turret or different kind of turret weapon system, be it similiar turret system as in Russian BMPT, or for example a gun-howitzer turret module or gun-mortar turret module, or anti-aircraft defence turret module.

Great Analysis!! I am learning from you...

So in summary an unmanned turret properly designed as the following advantages..

1. Weight Reduction: the reduction of weight gained can be put for more hull protection.
2. Interoperability: interchange with other turrets such as for artillery, anti aircraft, probably SAM units
3. Adaptable Modular Design: easy to change and update to newer upgrades.
4. Stealthier: with reduction of overall height of the tank with lower hull are more difficult to detect and cause hit.

Since we are almost done with the Arjun Mark – II testing, don't you think a newly designed turret for Arjun Mark- III is a logical next upgrade ?

 

[Damian]

Since we are almost done with the Arjun Mark – II testing, don't you think a newly designed turret for Arjun Mark- III is a logical solution?

It depends. If you wish to design manned turret, then it is not logical solution, it is a nececity.

However if you wish to use unmanned turret, then in fact you need to deeply redesign hull.

In the end you are actually designing a completely new tank.

Good example here are Americans, they designed a technology demonstrator for such tank, dubbed TTB - Tank Test Bed, which was based on M1 Abrams hull.

Look how deeply hull needed to be redesigned to fit unmanned turret and crew inside isolated compartment placed in hull front.

Standard M1A1.

M1 based TTB - Tank Test Bed. Note - it is only technology demonstrator, not even a prototype, it's sole purpose was to test different ideas and design solutions.

As you can see, TTB have much more compact unmanned turret, it's hull is slightly higher than standard hull, but the overall surface that is nececary to have heavy protection is much smaller.

Also frontal protection is far superior to a standard tank, because it can be thicker (armor thickness can be bigger than 1,000mm, level unachievable in conventional design within reasonable weight limit), while hull side protection can be achieved via different solutions (different type of side skirts and modules, but also by using several other design solutions).

 

[bose]

You are making wrong conclussions.

Soviets during Cold War were also thinking about greater crew survivability, however none of these ideas were bring beyond prototype stage due to different reasons.

Also, besides M1, all other NATO tanks, have very similiar crew survivability like Soviet tanks.

Don't you think the Israeli Merkava IV & German Leopard 2 beats the Soviet / Russian tanks such as T-80 / T-90 versions any day"¦

 

[Damian]

Don't you think the Israeli Merkava IV & German Leopard 2 beats the Soviet / Russian tanks such as T-80 / T-90 versions any day"¦

No they don't, in fact crew survivability in all these tanks is similiar in case of ammunition cook off.

Besides this, Merkava is inefficent design.

Due to it's size and internal volume as well as some other design solutions, Merkava is unnececary heavy. Front mounted engine and transmission makes hull front protection inferior to other designs, despite that myth of it's incredible survivability.

In fact Merkava Mk1 received engine at front, because Merkava was a primitive tank, compared for example to a much more modern T-72 used by Arab armies. Merkava Mk1 and Mk2 use a simple spaced steel armor, while T-72 used much more advanced composite armor.

Merkava received composite armor in it's Mk3 variant but only at turret. Merkava Mk4 is first Merkava tank with composite armor also on hull.

Leopard 2 on the other hand, stores only 15 rounds in safe magazine in turret bustle, rest, this is 27 rounds is stored in hull in a simple unprotected ammunition rack next to driver.

So no, I don't see why these tanks should be absolutely better in terms of survivability.

 

[methos]

It's always depending on what type of threat is engaged at what range. For example the Leopard 2 hull ammunition storage is quite well protected, because it's behind quite thick armour at the front and the sides (side armour should equal front armour in the frontal arc). If you can penetrate the frontal armour, then it doesn't really matter if there is ammunition behind or not, in both cases the crew will die.
On the other hand tanks like the T-72, the Al Khalid and the Arjun store their ammunition much further away from the frontal armour, which make the ammunition rack much more exposed for side attacks.

The M1 Abrams is contrary to what Damian likes to claim, not definetly the tank with the highest crew protection or the most survivable tank at all. The Leopard 2 & Challenger 2 turrets for example are better, because they do not have hydraulic turret and gun drives (which are highly enflammable and under very high pressure), better protected gun mantlets and (in case of the Leopard 2) also spall liners.

Another important question is what matters more: system survivability or crew survivability?

 

[Damian]

The M1 Abrams is contrary to what Damian likes to claim, not definetly the tank with the highest crew protection or the most survivable tank at all.

Real world and real wars proved that design solutions used in M1 were good decision that increased crew survivability and reduced crew losses to minimum.

Altough I know it is painfull for some people to admitt it.

If you can penetrate the frontal armour, then it doesn't really matter if there is ammunition behind or not, in both cases the crew will die.

It is not truth, defeated armor not allways means that crew will die. This is a misconception. The main reason why crews die is ammunition cook off after successfull armor perforation.

The Leopard 2 & Challenger 2 turrets for example are better, because they do not have hydraulic turret and gun drives (which are highly enflammable and under very high pressure),

This is another misconception. There are different types of hydraulic fluids. The older ones are indeed highly flammable, however Israeli experienced led US to design hydraulic fluids that are much less flammable. As for temperature of fluids it is indeed a problem, and fully electric drives are overall better.

And no, turrets of these tanks are not absolutely better.

Actually this is a situation with very high relativity. For one some of their solutions might be better, for some not.

Actually in terms of combat survivability, their turrets are far easier to be disabled by just destroying a weakly protected turret bustle which stores important components, like FCS, turret drives etc.

better protected gun mantlets and (in case of the Leopard 2) also spall liners.

Gun mantled is allways a weak zone, actually it is far better decision to reduce size and weight of gun mantle than increase it's size and have faith it will help survive a hit.

Another important question is what matters more: system survivability or crew survivability?

Crew survivability is far more important.

Vehicle can be repaired or replaced in a relatively short time. Crew can't be "repaired" or replaced in short time, also costs and time for training the crew, providing this crew with food, water, healthcare are high.

Not to mention that crew which knows that have higher survivability chance, will have better morale and will fight better, than crew that just saw a moment ago, how their collegues from another tank were burning alive inside a steel coffin.

A vehicle survivability can be addition.

We also need to look at a bigger image of today situation with armed forces around the world.

Due to economic crisis, armed forces are smaller. With smaller forces, any losses in personell are very harmfull to potential of these armed forces. In such situation, survivability of this personell becomes one of the highest priorities when designing different vehicles.

In such situation, nobody can ignore this characteristic anymore, at least none of the higher developed countries.

Of course none of all NATO MBT's can be considered as perfectly meeting all of today requirements, all of them are still cold war designs.

What NATO needs is a new Main Battle Tank design. The obvious question however is, if designing such vehicle is possible for all these countries separately with today economic crisis? Perhaps no. In such situation, perhaps the best solution would be NATO wide joint venture, in such situation, costs of production would be reduced thanks to high numbers of ordered vehicles, US Armed Forces would probably require to purchase approx 4000-5000 to completely replace M1 in active service.

But there is another problem, this problem are requirements. Different armed forces have different requirements, thus it would be nececary to make some sort of consensus on these requirements. Other thing is also not to make vehicle overexpensive, which means that requirements needs to be realistic.

Perhaps a good decision would be to agree that initially vehicles to be cheaper, will lack some solutions and systems, but will have provisions to include this lacking components through incremental upgrades during their service life.

Another good thing would standarization of components across armies.

But I think it is more and more obvious that NATO is slowly coming to a moment when replacement of current generation of MBT's becomes a nececity, and it would be good to start thinking right now, what to do.

And this is not only about MBT's, but also IFV's and other AFV's.

 

[methos]

Real world and real wars proved that design solutions used in M1 were good decision that increased crew survivability and reduced crew losses to minimum.

And still no other Western tank has been destroyed more often or has lost more crew members. Saying that the M1 has a high crew survivability rate is correct, but it does in real world not have a better than all these tanks with much lower crew survivability!

It is not truth, defeated armor not allways means that crew will die. This is a misconception. The main reason why crews die is ammunition cook off after successfull armor perforation.

Not for KE... besides there is plenty of fuel to burn in the M1's hull front.

This is another misconception. There are different types of hydraulic fluids. The older ones are indeed highly flammable, however Israeli experienced led US to design hydraulic fluids that are much less flammable.

It's no misconception. Even these "much less flammable" hydraulic fluids are still highly enflammable. Even hydraulic fluids like HFC and HFD (which are rated in industry and aerospace as "hardly enflammable") are going to be incinerated at normal penetration temperatures.

And no, turrets of these tanks are not absolutely better.

Fanboyism. They are better in the mentioned aspects.

Actually in terms of combat survivability, their turrets are far easier to be disabled by just destroying a weakly protected turret bustle which stores important components, like FCS, turret drives etc.

There is system redudancy. Besides, they are not "far easier to be disabled", since the Abrams also has parts of the hydraulic systems in the weakly armoured mid-section of the hull.

Gun mantled is allways a weak zone, actually it is far better decision to reduce size and weight of gun mantle than increase it's size and have faith it will help survive a hit.

It is a better decision, because of what?
Because it's not likely to be hit, right? Still you use the completely opposite logic to argue against the main sight placement of Leclerc and early Leopard 2, because it could be hit. Given that the mantlet is even greater than the main sights of these tanks, it looks sort of biased to say "doesn't matter on the M1, because it is a better decision" when at the same time you ignore the low probability of a hit on other tank's weakspots.

Faith is not going to help anybody under enemy fire.

Crew survivability is far more important.

...

What is a short time? Do you think in any potential real war scenario they still could produce new tanks without troubles? Not to mention that it takes several months to produce a single tank...

When the tank is hit and disabled, then the crew will not magically leave the battlefield. They have to sit in an immobilized tank directly in the combat zone. Unless they magically survive because they "have faith", the crew does have to make a risky attempt to leave the tank and return to base without being shot or they have risk being shot because the knocked out tank is still in the combat zone.

There is no simple answer like yours.

 

[Damian]

And still no other Western tank has been destroyed more often or has lost more crew members. Saying that the M1 has a high crew survivability rate is correct, but it does in real world not have a better than all these tanks with much lower crew survivability!

How many western tanks were deployed in such conditions? Even Challenger 2 tanks were not deployed in most dangerous regions of Iraq.

You statement is just a manipulation.

For example neither Leclerc neither Leopard 2 were used in such conditions and were not battle tested against modern RPG's or incredibly large IED's.

Not for KE... besides there is plenty of fuel to burn in the M1's hull front.

Also for KE. And this fuel there is for protection. Ballistic tests prove, that fuel tanks full of fuel encased on their own compartments can provide high degree of ballistic protection.

It's no misconception. Even these "much less flammable" hydraulic fluids are still highly enflammable. Even hydraulic fluids like HFC and HFD (which are rated in industry and aerospace as "hardly enflammable") are going to be incinerated at normal penetration temperatures.

It is misconception.

I never seen in any report from Iraq, that hydraulic fluids were problematic.

Fanboyism.

And can you provide something that at least can look like an argument?

For me fanboyism is your approach to prize a vehicle that have minimal crew survivability and to promote design solutions that were disregarded for any future MBT's design, like ammunition in crew compartment.

There is system redudancy. Besides, they are not "far easier to be disabled", since the Abrams also has parts of the hydraulic systems in the weakly armoured mid-section of the hull.

So Fire Control System and turret drives are redundant on battlefield? It is a very interesting concept, maybe for you German speaking people crew survivability is also redundant? Or vehicle capability to defend itself?

As for hull, of course that hull does not have super thick side armor, however hull is far more difficult to hit than turret.

A fact proven by many conflicts, tests and calculations.

It is a better decision, because of what?
Because it's not likely to be hit, right? Still you use the completely opposite logic to argue against the main sight placement of Leclerc and early Leopard 2, because it could be hit. Given that the mantlet is even greater than the main sights of these tanks, it looks sort of biased to say "doesn't matter on the M1, because it is a better decision" when at the same time you ignore the low probability of a hit on other tank's weakspots.

Faith is not going to help anybody under enemy fire.

Because size reduction of gun mantled is a good decision for several reasons, like minimizing hit probability, it's penetration probability and also reducing it's weight.

Same for sight placement, placing sight behind main armor and through turret roof, means that probability of penetrating a weak zone is completely eliminated.

And there is nothing about faith here.

Also the best way to eliminate these weak zones is to use unmanned turrets.

What is a short time? Do you think in any potential real war scenario they still could produce new tanks without troubles? Not to mention that it takes several months to produce a single tank...

Did you ever heard about war reserve stocks?

Oh wait, yes I remember now, Germany and other German language countries allmost do not have any reserve stocks.

When the tank is hit and disabled, then the crew will not magically leave the battlefield. They have to sit in an immobilized tank directly in the combat zone. Unless they magically survive because they "have faith", the crew does have to make a risky attempt to leave the tank and return to base without being shot or they have risk being shot because the knocked out tank is still in the combat zone.

Well, in such situation, definetely, German solution to kill a crew in disabled tank by allowing ammunition to cook off is the best solution. It finishesh all further problems.

There is no simple answer like yours.

To the contrary, there are simple answers to such simple problems.

This is why all future tank projects had crew in isolated compartment, isolated from ammunition, and why crew survivability was considered as one of the most important factors.


But as I said, all of the current NATO 3rd generation of tanks slowly becomes obsolete, this also includes M1. And at some point, further modernization will be immposible or pointless.

This is why completely new design is nececary, which means sooner or later, we will need to design 4th generation.

 

[methos]

You statement is just a manipulation.

It is not. You cannot say stuff like "It's the best in terms of crew survivability, look at real life", when other tanks have achieved the same level of de facto crew survivability in real life.
Yes, the Challenger 1 & 2, Leopard 2, Leclerc etc. did not saw exactly the same type of combat the M1 did see. Still you cannot claim because of this that they are less survivable, because you don't know if they had performed worse.

Also for KE. And this fuel there is for protection. Ballistic tests prove, that fuel tanks full of fuel encased on their own compartments can provide high degree of ballistic protection.

No, not really. KE works much different and has a much greater mass, hence it's much more lethal by itself. There are numerous photographs from the interior of vehicles after being penetrated by KE ammunition, the damage there is much greater.
The fuel is not there because it is supposed to work as armour, it's there because it has to be stored somewhere and the rear is occupied already by ammunition storage, engine and co. The fuel does increase the protection as much as an engine increases protection: it might help stopping the round first, but while doing so it will be incinerated and forcing the crew to abbandon the vehicle.

It is misconception.

I never seen in any report from Iraq, that hydraulic fluids were problematic.

And I have never seen that the armour of the Leclerc was penetrated - is it impenetratable then? No! Let's take a look at the following: The Isrealis used hydraulic drives, but switched to electric on the later Merkavas. The Leopard 2 originally used hydraulic drives, but then it was switched to electric ones. The Challenger 1 had hydraulic drives, but the Challenger 2 electric ones... and in all these cases it has been reported that this was done to increase crew survivability.

For me fanboyism is your approach to prize a vehicle that have minimal crew survivability and to promote design solutions that were disregarded for any future MBT's design, like ammunition in crew compartment.

I am not promoting it, I just don't see the validity in your claims. By statistics the hull is already less likely to be hit and the frontal arc of the hull is armoured by a higher degree than on the M1 Abrams. You put tanks with rather proven survivability (like the Merkava IV or arguably the Leopard 2) in the same category with the T-72, because all other tanks "behave similar". That in fact the hull ammunition is pretty much stored in an optimal way (militarysta did make drawings for this) is completely ignored by you.

So Fire Control System and turret drives are redundant on battlefield? It is a very interesting concept, maybe for you German speaking people crew survivability is also redundant? Or vehicle capability to defend itself?

You know that redundant means that there are back up systems? If the fire control does stop working (which also can hit after a simple 25 mm APDS at the main sight), then the gunner still has it's backup sight. If the turret drives are hit, then the turret still can be turned (in case of the Leopard 2A4 there is a manual pump for the hydraulics).

Because size reduction of gun mantled is a good decision for several reasons, like minimizing hit probability, it's penetration probability and also reducing it's weight.

It is a good idea, but doesn't mean that you can simply ignore factors like the actual armour protection. If everybody wanted reduced weight on the gun mounting and the smallest possible size, all tanks would have a mantletless design like the Chieftain. But that doesn't turn out as being very good IRL!
If you have to chose between two different mantlet designs, one with enough armour to survive most anti-tank weapons in existence (because you have thick composite armour) and the other with nearly no armour protection, but only half the surface, which would you choose?

Same for sight placement, placing sight behind main armor and through turret roof, means that probability of penetrating a weak zone is completely eliminated.

Yes, but that's not what we are discussing here. The M1 Abrams does have a very thin mantlet only which is not well armoured. In the same way the armour block behind gunner's sight of the Leopard 2A4 is not very well armoured (but much thicker than the M1's mantlet). The gunner's sight is smaller than the M1 Abrams' mantlet, still you completely have only the opinion "good M1 Abrams, bad other tanks".

Did you ever heard about war reserve stocks?

Oh wait, yes I remember now, Germany and other German language countries allmost do not have any reserve stocks.

Guess what, during Cold War nobody had... but conscription is also a way to have a "human reserve stock".

Well, in such situation, definetely, German solution to kill a crew in disabled tank by allowing ammunition to cook off is the best solution. It finishesh all further problems.

Only when the frontal armour was penetrated, but you are only avoiding the question.

This is why all future tank projects had crew in isolated compartment, isolated from ammunition, and why crew survivability was considered as one of the most important factors.

Future tank projects also had two sets of computer and some even two sets of driver equipment (like it was for example tested on the VT-2000).

 

[Damian]

It is not. You cannot say stuff like "It's the best in terms of crew survivability, look at real life", when other tanks have achieved the same level of de facto crew survivability in real life.
Yes, the Challenger 1 & 2, Leopard 2, Leclerc etc. did not saw exactly the same type of combat the M1 did see. Still you cannot claim because of this that they are less survivable, because you don't know if they had performed worse.

Yes I can claim, as this is supported by logic and their design. Unprotected ammunition compartment will allways be less safe than isolated ammunition compartment.

No, not really. KE works much different and has a much greater mass, hence it's much more lethal by itself. There are numerous photographs from the interior of vehicles after being penetrated by KE ammunition, the damage there is much greater.
The fuel is not there because it is supposed to work as armour, it's there because it has to be stored somewhere and the rear is occupied already by ammunition storage, engine and co. The fuel does increase the protection as much as an engine increases protection: it might help stopping the round first, but while doing so it will be incinerated and forcing the crew to abbandon the vehicle.

Not every KE hit will end up with killing whole crew. Besides such argument points out that you don't see any reason to increase crew survivability.

And no, not every hit in fuel tanks will end up incinerating that fuel.

Also fuel tanks were mainly placed there for additional protection. Not because it was only place to place them, in fact M1 could have fuel tanks in overtrack sponsons.

And I have never seen that the armour of the Leclerc was penetrated - is it impenetratable then? No! Let's take a look at the following: The Isrealis used hydraulic drives, but switched to electric on the later Merkavas. The Leopard 2 originally used hydraulic drives, but then it was switched to electric ones. The Challenger 1 had hydraulic drives, but the Challenger 2 electric ones... and in all these cases it has been reported that this was done to increase crew survivability.

I do not deny that electric drives increase survivability, I deny overexaggarating this issue.

You know that redundant means that there are back up systems? If the fire control does stop working (which also can hit after a simple 25 mm APDS at the main sight), then the gunner still has it's backup sight. If the turret drives are hit, then the turret still can be turned (in case of the Leopard 2A4 there is a manual pump for the hydraulics).

By your logic all important systems should be exposed then. However in reality the most important systems should be as well protected as possible.

It is a good idea, but doesn't mean that you can simply ignore factors like the actual armour protection. If everybody wanted reduced weight on the gun mounting and the smallest possible size, all tanks would have a mantletless design like the Chieftain. But that doesn't turn out as being very good IRL!
If you have to chose between two different mantlet designs, one with enough armour to survive most anti-tank weapons in existence (because you have thick composite armour) and the other with nearly no armour protection, but only half the surface, which would you choose?

I would choose the second, not to mention that actually smaller mantled can have comparable armor protection through higher density.

I do not support fully mantledless design tough.

Yes, but that's not what we are discussing here. The M1 Abrams does have a very thin mantlet only which is not well armoured. In the same way the armour block behind gunner's sight of the Leopard 2A4 is not very well armoured (but much thicker). The gunner's sight is smaller than the M1 Abrams' mantlet, still you completely have only the opinion "good M1 Abrams, bad other tanks".

You don't know the protection level of gun mantled. This gun mantled as per avaiable sources also use composite armor (Hunnicutt mentions that originally mantled was made from pure steel, later during FSED development phase it was changed to composite design).

And my opinion is justified, although I did not said that other tanks are bad, in their case survivability was just not a priority.

Guess what, during Cold War nobody had... but conscription is also a way to have a "human reserve stock".

Maybe Germany did not had reserve stocks, but major players had like US or USSR. Damn even my country back then had reserve stocks that were relatively big, although in the 1980's mostly composed from obsolete equipment.

Only when the frontal armour was penetrated, but you are only avoiding the question.

I am not, besides real life answered to such question, crew have chances to evac itself from disabled vehicle, or can wait inside and pretend they are "dead".

Future tank projects also had two sets of computer and some even two sets of driver equipment (like it was for example tested on the VT-2000).

And such ideas are also worth to be considered again, especially that today technology gives greater capabilities to actually implement such solutions.