MBT 70 family

Colonial-Marine said:

I think he was talking about the 152mm gun/missile launcher and many of the features of the design. While technologies like gun launched missiles, laser rangefinders, hydropneumatic suspension, and etc. may seem reliable today, they were all cutting edge back then. Some of the other features seem plain foolish or overly complex from today's point of view, like putting the entire crew in the turret, or a remote control 20mm cannon that is stored in a hatch behind the driver's position when not in use.

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If you are going to make such hindsight laden calls you could at least have your facts right. There was nothing ‘foolish’ in the MBT-70 design. It was developed and engineered by actual experts – rather than ignorance feed armchair commentators – who developed an extremely effective tank design for all the best reasons. The project was let down in the end by the Shillelagh missile guidance system which being central to its lethality was a single point of failure that could and did destroy the project. Since many other guided missiles were fielded in this time period as a concept it wasn’t flawed just badly executed.

The MBT-70 configuration of all crew in the turret was not determined by a whim it was a method that significantly reduce the height of the turret roof by allowing for a much lower hull because no driver was in it. Lower roof height reduced the amount of surface area exposed to the enemy; enabling for weight efficiencies in armouring. Height is also the prime driver in visual detection so it increased survivability. Sure the rotating driver pod was a compromise that made things difficult but it was like the S-Tank fixed gun something that could be lived with if you had to. Later versions of the MBT-70 dispensed with it and placed the driver in a very reclined position within the hull.

All of the other technology in the vehicle worked. Including the remotely controlled secondary gun which beared no similarity to the type of TV driven weapon stations we have today. Like thousands of other contemporary weapon stations this system used an offset periscope or sight controller (see the AH-56 thread).

Colonial-Marine said:

I The spaced armor was certainly an improvement from the pure RH steel like on the M60. Yet it wasn't as much of a leap foward as new composite armors like the Chobham design the Abrams uses. The front armor wouldn't be nearly as capable as that of the original M1, not to mention a new M1A2 SEP. When it comes to the rest of the armor I can't be sure, but the Abrams probably had the advantage in side armor protection at least.

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Ever heard of time? You know it’s that annoying thing that makes simplistic hindsight driven comments like this laughable. Since the original M1 (XM815) designs were prepared BEFORE Chobham type armour was available and AFTER the MBT70 project was abandoned how do you suggest that the MBT70 is somehow deficient in armour? Of course if the MBT70 entered production it could be upgraded with Chobham and DU armour as they became available.

Abraham Gubler said:

If you are going to make such hindsight laden calls you could at least have your facts right. There was nothing ‘foolish’ in the MBT-70 design. It was developed and engineered by actual experts – rather than ignorance feed armchair commentators – who developed an extremely effective tank design for all the best reasons. The project was let down in the end by the Shillelagh missile guidance system which being central to its lethality was a single point of failure that could and did destroy the project. Since many other guided missiles were fielded in this time period as a concept it wasn’t flawed just badly executed.

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I said they seem downright foolish TODAY, not back then. And indeed many guided missiles were being fielded during the time, yet actually having it fired by the gun was a new concept, and much more problematic than expected as the Sheridan and M60A2 demonstrated.

Abraham Gubler said:

The MBT-70 configuration of all crew in the turret was not determined by a whim it was a method that significantly reduce the height of the turret roof by allowing for a much lower hull because no driver was in it. Lower roof height reduced the amount of surface area exposed to the enemy; enabling for weight efficiencies in armouring. Height is also the prime driver in visual detection so it increased survivability. Sure the rotating driver pod was a compromise that made things difficult but it was like the S-Tank fixed gun something that could be lived with if you had to. Later versions of the MBT-70 dispensed with it and placed the driver in a very reclined position within the hull.

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I know the reasons for putting the crew in the turret and on paper the idea makes sense. Yet by all accounts it did not work very well in practice. Today when the problems are evident and the technology has improved to the point where future designs place the whole crew in the hull, it seems foolish in retrospect. I don't think it could have been lived with if it became a mechanical liability over time either. I was not aware any later versions had the driver in the hull, I believe the XM803 still had the driver's counter-rotating turret, although with some revisions to the optics setup.

Abraham Gubler said:

All of the other technology in the vehicle worked. Including the remotely controlled secondary gun which beared no similarity to the type of TV driven weapon stations we have today. Like thousands of other contemporary weapon stations this system used an offset periscope or sight controller (see the AH-56 thread).

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Working in testing and working continuously in the field are different things entirely. Over the years I have talked to several former tankers who were serving when the MBT-70 was expected to be the next tank. Their opinion on the MBT-70 was less than positive to put it nicely. Obviously they never operated the actual vehicle but they figured the suspension would be an utter nightmare to maintain among other things. From what I have read the 20mm autocannon did not work as well as it should have either. Good concept but flawed execution.

Abraham Gubler said:

Ever heard of time? You know it’s that annoying thing that makes simplistic hindsight driven comments like this laughable. Since the original M1 (XM815) designs were prepared BEFORE Chobham type armour was available and AFTER the MBT70 project was abandoned how do you suggest that the MBT70 is somehow deficient in armour? Of course if the MBT70 entered production it could be upgraded with Chobham and DU armour as they became available.

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My God, get off your damn high horse. I don't know what I did to piss you off but get over it. I was responding to Grey Havoc's post about the armor of the MBT-70 being enough to stand up to most of the IEDs and RPGs we face today. At some point Chobham armor was bound to be incorporated onto the tank if it entered service, although who knows how much of a redesign would have been involved?

Abraham Gubler said:

The MBT-70 configuration of all crew in the turret was not determined by a whim it was a method that significantly reduce the height of the turret roof by allowing for a much lower hull because no driver was in it. Lower roof height reduced the amount of surface area exposed to the enemy; enabling for weight efficiencies in armouring. Height is also the prime driver in visual detection so it increased survivability. Sure the rotating driver pod was a compromise that made things difficult but it was like the S-Tank fixed gun something that could be lived with if you had to. Later versions of the MBT-70 dispensed with it and placed the driver in a very reclined position within the hull.

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This was because they had failed to appreciate the human engineering problems associated with the disorientation that the driver experienced in his counter-rotating cylinder in the turret. He no longer had the visual cues which he subconsciously relied upon from the corners of the hull with the result that he often reported that he didn't know where the tank was pointing as the turret revolved around him.

Then there was also the problem that his presence caused to the commander's vision. It blocked the commander from seeing properly to the quarter-left quadrant and reduced his situational awareness in that direction. Both are reasons why the driver in the turret concept died with the MBT-70 design.

While returning the driver to the hull helped both problems, it meant that the hull had to be extended in length to accommodate him, which caused other problems with vehicle manoeuvrability and increased weight because of increased armour volume.

I would suggest that the MBT-70 was an interesting experiment and while well designed, it was actually foolish to think that the repositioning of the driver was going to work very well but I suppose it had to be tried, to see if it could work. However, I'd have done it on a testbed, rather than a prototype which was intended to go into production.

Luddite question time again!!!

How did the contra rotating drivers position work. The concept seems straight forward enough to me, until you add the gun. How did the driver pass the mass of the gun breech, was the drivers ring low enough to pass under it?

I seem to recall seeing a line drawing of the turret layout somewhere. Anyone have one?

I am; as always, grateful for any clarification.

Regards.

The driver sat in a revolving seat offset from the main axis of the turret, so he was always on the same side of the gun, turning the opposite way, and supposedly always looking towards the front of the tank. But no wonder he got dizzy. I hope I've understood the arrangement.

rickshaw said:

This was because they had failed to appreciate the human engineering problems associated with the disorientation that the driver experienced in his counter-rotating cylinder in the turret. He no longer had the visual cues which he subconsciously relied upon from the corners of the hull with the result that he often reported that he didn't know where the tank was pointing as the turret revolved around him.

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No one relies on ‘subconscious’ visual cues when driving tanks. Tank drivers are trained to orientate their understanding of the tank’s path in the same way any other vehicle driver is through familiarity with the interrelation of its movement with their perception. The problem with the rotating driver’s position is it DISPLACES as the turret rotates. While the driver may still be pointing in the same direction they have been moved to the right or left or back or forwards. So their understanding of where the tank is moving relative to their field of view is wrong as their position is changed. This can be countered by fitting the driver’s forward optic with an adjusting reticule which counter displaces as the position displaces and retains marks showing the path of the vehicle.

The turret position has several advantages as well based on actual tank driving practise. Driving conventional tanks is a two person job with the commander located high in the turret with a 360 degree field of view directing teh driver with their low down, limited field of view. The MBT-70’s position frees the commander of this job as it provides the driver with the same field of view as the commander. By being higher up they have a much better appreciation of the terrain in front of the tank and can avoid obstacles without commander intervention. Also when the tank needs to reverse the driver’s pod can rotate to the rear and enable the driver to see where they are going (poorly but better than nothing) while keeping the front of the tank with its heavy armour, sensors and weapons pointed at the enemy.

rickshaw said:

Then there was also the problem that his presence caused to the commander's vision. It blocked the commander from seeing properly to the quarter-left quadrant and reduced his situational awareness in that direction. Both are reasons why the driver in the turret concept died with the MBT-70 design.

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This isn’t a real problem. There are plenty of things on the turret roof which may block commander’s field of view (gunner’s sights, spot lights, MGs, etc) if they are just peaking over the hatch. Certainly any tank design with attention to detail positions vision blocks and the like to provide a clear field of view through the obstacles.

rickshaw said:

I would suggest that the MBT-70 was an interesting experiment and while well designed, it was actually foolish to think that the repositioning of the driver was going to work very well but I suppose it had to be tried, to see if it could work. However, I'd have done it on a testbed, rather than a prototype which was intended to go into production.

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The problem was not the design but cost. With the Vietnam War consuming 50% of the US defence budget in the late 60s, early 70s even a conventional new tank design in this time frame would have been killed off. The concept of the turret mounted driver died with the MBT70 because technology had moved on. Those tanks that were built after the MBT70 were done so as low risk designs to a limited budget. After them the incorporation of TV into tank designs enabled all the crew to be moved into the hull and their elevated fields of view to be provided by cameras mounted above the gun. While this technology has yet to manifest itself beyond testbeds, prototypes and other funding killed pre production vehicles it is the way of the future.

Colonial-Marine said:

I know the reasons for putting the crew in the turret and on paper the idea makes sense. Yet by all accounts it did not work very well in practice. Today when the problems are evident and the technology has improved to the point where future designs place the whole crew in the hull, it seems foolish in retrospect.

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Retrospect means to reflect upon past events. It does not mean to judge past events by a changed standard available only in our current time. Of course no one would design a tank with 21st century technology using 1960s solutions. You might as well laugh haughtily at the designers of the Sopwith Camel for not using a cantilever monoplane configuration with a fuel injected inverse V engine. And say such a design is “foolish in retrospect”.

Colonial-Marine said:

Obviously they never operated the actual vehicle but they figured the suspension would be an utter nightmare to maintain among other things.

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Hydro suspension compared to torsion bars shifts the maintenance burden from little work maintaining with intense and laboured efforts for replacement to frequent maintaining with little work for replacement. From an Army’s perspective this means more tanks in the field and less in the workshop, even if it adds a couple of man hours to the daily crew workload. It also reduces overall weight, significantly improves underbelly protection and enables the tank to be orientated for improved reverse slope fields of fire. It costs more but makes your tank a much better unit. General Tal’s no.1 regret from the Merkava Mk 4 project is they didn’t have the money to replace the suspension with hydro units (and they don’t even use torsion bars).

Colonial-Marine said:

My God, get off your damn high horse. I don't know what I did to piss you off but get over it. I was responding to Grey Havoc's post about the armor of the MBT-70 being enough to stand up to most of the IEDs and RPGs we face today. At some point Chobham armor was bound to be incorporated onto the tank if it entered service, although who knows how much of a redesign would have been involved?

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When surrounded by so many people making comments about things of which they have little understanding being on a high horse is a great place to be. Further I find it deeply offensive that people who are in the whole just hobbyist and enthusiasts with little or no practical understanding can be so insulting of the efforts of actual real weapons designers and practitioners who conceived these systems. Calling their efforts “foolish” is not only totally wrong but also greatly disrespectful.

Spaced metal armour is going to be just as good as Chobham against RPGs and IEDs. The problem here is alignment of the armour; in that IED and RPG attacks by insurgents come from the flanks and rear not the front. So in both cases (MBT70 and M1) they are just as in danger. See it’s amazing what more you can see from a high horse...

JohnR said:

How did the contra rotating drivers position work. The concept seems straight forward enough to me, until you add the gun. How did the driver pass the mass of the gun breech, was the drivers ring low enough to pass under it?

I seem to recall seeing a line drawing of the turret layout somewhere. Anyone have one?

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Here is some History Channel video introducing the tank (no turret rotation)

http://www.youtube.com/watch?v=YE7CUO0yuMo

Attached is a picture of a modified T95 used as a crew in turret test bed for the MBT(MR) which was the project before the Germans got involved in 60/61 and was renamed the MBT-70. This picture shows how the drivers position would counter rotate to the turret to keep it facing forward. Also attached is a picture of the MBT(MR) design before it became the MBT-70.

Abraham Gubler said:

Retrospect means to reflect upon past events. It does not mean to judge past events by a changed standard available only in our current time. Of course no one would design a tank with 21st century technology using 1960s solutions. You might as well laugh haughtily at the designers of the Sopwith Camel for not using a cantilever monoplane configuration with a fuel injected inverse V engine. And say such a design is “foolish in retrospect”.

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Yet even judging it from a 1960s standard it turned out to be a mistake. It may have looked good on paper but it certainly wasn't effective enough in reality for plenty of reasons.

Abraham Gubler said:

Hydro suspension compared to torsion bars shifts the maintenance burden from little work maintaining with intense and laboured efforts for replacement to frequent maintaining with little work for replacement. From an Army’s perspective this means more tanks in the field and less in the workshop, even if it adds a couple of man hours to the daily crew workload. It also reduces overall weight, significantly improves underbelly protection and enables the tank to be orientated for improved reverse slope fields of fire. It costs more but makes your tank a much better unit. General Tal’s no.1 regret from the Merkava Mk 4 project is they didn’t have the money to replace the suspension with hydro units (and they don’t even use torsion bars).

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Hydro-pneumatic suspension was then a relatively unproven technology and even today use on military vehicles has been relatively limited. In my opinion it would have taken continued operational use in the field to have effectively determine it's reliability and maintainability. As far as it's use on the Korean K2 and potential use on the Merkava 4, the technology has obviously improved, but back then they may have been reaching too far as were many of the technologies on the MBT-70.

Colonial-Marine said:

When surrounded by so many people making comments about things of which they have little understanding being on a high horse is a great place to be. Further I find it deeply offensive that people who are in the whole just hobbyist and enthusiasts with little or no practical understanding can be so insulting of the efforts of actual real weapons designers and practitioners who conceived these systems. Calling their efforts “foolish” is not only totally wrong but also greatly disrespectful.

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Acting with an attitude of superiority based on the assumption that nobody else knows what they are talking about is not a great place to be. I don't think poorly of the designers on the MBT-70 or many canceled projects. Sea Dart, XFV-12, Boeing 2707, AH-56, and plenty of projects were all based around sound concepts and real engineering. In many cases those involved should be praised for the progress they did achieve. Yet concepts don't work out as well as predicted and unforeseen problems occur. In many examples like the MBT-70 the designers were pushing the technological limits of the time too, which is bound to effect cost, maintainability, and other aspects. Sometimes a piece of equipment is doomed due to cost-saving measures, and a project is just simply over-engineered.

Colonial-Marine said:

Spaced metal armour is going to be just as good as Chobham against RPGs and IEDs. The problem here is alignment of the armour; in that IED and RPG attacks by insurgents come from the flanks and rear not the front. So in both cases (MBT70 and M1) they are just as in danger. See it’s amazing what more you can see from a high horse...

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Against a typical IED? Spaced armor will be just as useful I suppose, yet against a RPG this isn't the case. Spaced armor simply isn't going to provide the same level of protection as Chobham in terms of the eRHA value against a shaped-charge weapon. as advanced composite armors. And this matters when the enemy is firing more than early PG-7 variants. RPG-29s and etc. have been recovered in Iraq for example. As far as the flanks and rear go, indeed they are vulnerable on both tanks, but more specific details of the armor thickness isn't available of course.

*Edited to keep the discussion civil.*

Colonial-Marine said:

Yet even judging it from a 1960s standard it turned out to be a mistake. It may have looked good on paper but it certainly wasn't effective enough in reality for plenty of reasons.

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Try one and a half million reasons: that’s the cost per tank in dollars. Which in the 1960s was a lot of money! The only thing that didn’t work was the missile launcher. The German’s solved this problem by using a high velocity gun but the American’s wedded to the Shillelagh ran the XM803 into further fiscal nightmares. Both MBT-70 spin offs were destroyed by the oil shock and both Armies launched supposedly low cost, simple projects to develop a new evolutionary tank from their 1950s designs. Beyond Shillelagh where in all this is evidence that the tank was no good? If there was no Vietnam War then the M70 Marshall tanks would have crushed the Iraqi Army just as quickly as the M1 Abrams tanks (probably quicker as they had better operational mobility).

Colonial-Marine said:

Hydro-pneumatic suspension was then a relatively unproven technology and even today use on military vehicles has been relatively limited. In my opinion it would have taken continued operational use in the field to have effectively determine it's reliability and maintainability. As far as it's use on the Korean K2 and potential use on the Merkava 4, the technology has obviously improved, but back then they may have been reaching too far as were many of the technologies on the MBT-70.

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It was proven on hundreds of thousands of Citroens DSes. Pretty hard to improve on that... It’s another myth to claim that the MBT-70 was held back by its suspension or that it is unreliable and too much of a maintenance burden. Certainly compared to what you need to go through if a torsion bar breaks hydro-pneumatic suspension is a god send. Since maintenance of hydro-pneumatic suspension is mostly just changing the fluids and seals it’s not much different to maintaining tank transmission, brakes and the turret hydraulic systems. But heah lets not let facts intrude on ‘ess dif-er-ent ‘n I dona like et’ opinioning...

Colonial-Marine said:

Against a typical IED? Spaced armor will be just as useful I suppose, yet against a RPG this isn't the case. Spaced armor simply isn't going to provide the same level of protection as Chobham in terms of the eRHA value against a shaped-charge weapon. as advanced composite armors. And this matters when the enemy is firing more than early PG-7 variants. RPG-29s and etc. have been recovered in Iraq for example. As far as the flanks and rear go, indeed they are vulnerable on both tanks, but more specific details of the armor thickness isn't available of course.

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Will an RPG-7V (85mm HEAT) penetrate the frontal armour of an MBT-70 or similar spaced armour tank? Nope. It won’t penetrate the frontal armour of an M1, CR, Leopard 2, etc with chobham armour, either. So what’s the difference? Ahh advanced tandem warhead anti-tank launchers that just happen to have the letters RPG in the name and the like... OK got me there... Semantics wins another debate... But this is all very immaterial the MBT-70 with spaced armour would never be driving around the 21st century battlefields. Maybe the M70A3 Marshall with DU composite armour would be...

Colonial-Marine said:

I don't think poorly of the designers on the MBT-70 or many canceled projects. Sea Dart, XFV-12, Boeing 2707, AH-56, and plenty of projects were all based around sound concepts and real engineering. In many cases those involved should be praised for the progress they did achieve.

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Sure but you’re more than willing to degrade their efforts until someone calls you out over it. It’s easy to jump on the bandwagon and throw stones at fallen giants. But projects can fail for many reasons and most are not associated with engineering.

Colonial-Marine said:

Acting with an attitude of superiority based on the assumption that nobody else knows what they are talking about is not a great place to be.

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Don’t mistake ripping your arguments apart as somehow an attitude of superiority. You are the one making the unsupported statements and offering these opinions. I’m not turning around and saying “you’re wrong, you’re wrong, I’m better than you...” etc. I’m just showing where you are wrong and providing the facts to prove it. I’m also calling you out on your simplistic and unjust reasoning that has lead you to these statements. This may not be pleasant for you but it certainly isn’t personally motivated.

AG said

The problem was not the design but cost.

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But the reason for the cost was the design - in one word, over-complex.
Anachronistic, but compare the T34. (Or the $6million zero gravity ball-point pen project, when a pencil would have done the job)

The same might be said of the arguments now presented.
JohnR asked about the driver in terms which accepted his own lack of basic knowledge of how the turret worked, so an answer needs to be on the same level.
I'm interested to know of the additional complications of the driver being displaced backwards and forwards relative to the body of the tank. Were these anticipated by the designers, or found on trial? I see the [proposed?] solution needs further complex components.

AG said

When surrounded by so many people making comments about things of which they have little understanding being on a high horse is a great place to be. Further I find it deeply offensive that people who are in the whole just hobbyist and enthusiasts with little or no practical understanding can be so insulting of the efforts of actual real weapons designers and practitioners who conceived these systems. Calling their efforts “foolish” is not only totally wrong but also greatly disrespectful.

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I suppose I fall into the class of those with little or no practical understanding, but sometimes an ounce of theory is valuable, and theory can be learned. I'm no expert on tank design, with only a passing interest in it. But I have had a more extensive long term interest in warships, and after retiring three years ago, encouraged by others' discussions on a discussion board like this, I've made a quite detailed study of warship design problems, which are more difficult even than those of tanks, and generally need to be solved first time, as there are no prototypes. I have been greatly helped in this by the answers to my sometimes rather naive early questions by more experienced naval historians, naval officers and naval architects. None of them found it necessary to sit on a high horse. DK Brown in particular had a great reputation for helping even the rawest beginner. He sent me copies of his own student project cruiser design to help me understand the wide gulf between sketch designs and as-fitted designs, and the huge amount of work which goes between.
I do understand the frustration when not-so-knowledgeable enthusiasts seek to alter the work of expert designers done 50 or 150 years ago. (Warships go back further than tanks, to an era with very different 'advanced technology'.) This is especially so when they refuse to accept facts as facts not opinions. I did go so far as to end one of my posts by saying "you are not really arguing with me, but with Attwood and Goodall, generally regarded as very competent designers". But ships offer far greater scope than do tanks for enthusiasts to substitute one type of gun for another, change layouts, alter fuel (from coal to oil) and so on. After all, websites like this are not primarily forums for professional experts, but for enthusiasts, and not all of their suggestions are totally foolish. Nor are all the designs of experts in their day free from sometimes basic errors, particularly if working under great pressure. If you don't believe that, consider HMS Captain in the late 1800s, or even the controversial designs of HMS Dreadnought, Invincible and Renown at the beginning of the twentieth century, or the cracks in the Southampton class cruisers and the stability problems of the Hunt class destroyers at the beginning of World War II. The designers making the errors were not shot. The prime objective was to correct the mistakes, which needed their scarce expertise. You can learn to accept these things, and be both civil and helpful.

Abraham Gubler said:

rickshaw said:

This was because they had failed to appreciate the human engineering problems associated with the disorientation that the driver experienced in his counter-rotating cylinder in the turret. He no longer had the visual cues which he subconsciously relied upon from the corners of the hull with the result that he often reported that he didn't know where the tank was pointing as the turret revolved around him.

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No one relies on ‘subconscious’ visual cues when driving tanks. Tank drivers are trained to orientate their understanding of the tank’s path in the same way any other vehicle driver is through familiarity with the interrelation of its movement with their perception. The problem with the rotating driver’s position is it DISPLACES as the turret rotates. While the driver may still be pointing in the same direction they have been moved to the right or left or back or forwards. So their understanding of where the tank is moving relative to their field of view is wrong as their position is changed. This can be countered by fitting the driver’s forward optic with an adjusting reticule which counter displaces as the position displaces and retains marks showing the path of the vehicle.

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Abraham, have you ever driven an armoured vehicle? You are of course a trained tank driver, afterall, you speak so authoritatively. I've discussed the MBT-70 with someone who actually drove one during the trials. He was rather uncomplimentary about its innovations. I'll take his word over yours.

The turret position has several advantages as well based on actual tank driving practise. Driving conventional tanks is a two person job with the commander located high in the turret with a 360 degree field of view directing teh driver with their low down, limited field of view. The MBT-70’s position frees the commander of this job as it provides the driver with the same field of view as the commander. By being higher up they have a much better appreciation of the terrain in front of the tank and can avoid obstacles without commander intervention. Also when the tank needs to reverse the driver’s pod can rotate to the rear and enable the driver to see where they are going (poorly but better than nothing) while keeping the front of the tank with its heavy armour, sensors and weapons pointed at the enemy.

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There is a reason why they used to place the vehicle commander at the highest point of the vehicle, Abraham. Putting someone on the same level, in front of him, robs him of the advantage that position conveys. This is one reason why most tankers are very critical of moves to place the commander in the hull.

rickshaw said:

Then there was also the problem that his presence caused to the commander's vision. It blocked the commander from seeing properly to the quarter-left quadrant and reduced his situational awareness in that direction. Both are reasons why the driver in the turret concept died with the MBT-70 design.

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This isn’t a real problem. There are plenty of things on the turret roof which may block commander’s field of view (gunner’s sights, spot lights, MGs, etc) if they are just peaking over the hatch. Certainly any tank design with attention to detail positions vision blocks and the like to provide a clear field of view through the obstacles.

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See my point above. Yes, there are plenty of other objects. None are as big or in the same position of the driver's position on the MBT-70. It is in a critical quadrant of the commander's vision. It prevents him from having that magic 6400 mil view. Therefore it is less than optimum.

rickshaw said:

I would suggest that the MBT-70 was an interesting experiment and while well designed, it was actually foolish to think that the repositioning of the driver was going to work very well but I suppose it had to be tried, to see if it could work. However, I'd have done it on a testbed, rather than a prototype which was intended to go into production.

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The problem was not the design but cost.

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That is your opinion. I beg to differ. "Cost" was a convenient excuse. If the US Army had really wanted the MBT-70 it would have found the dosh to pay for it. The reality was that it was too advanced for the technology of the day and so represented a failure. It was a case of technological over-reach by pushing the envelope too hard. Something the US military has proven very prone to.

Abraham Gubler said:

Try one and a half million reasons: that’s the cost per tank in dollars. Which in the 1960s was a lot of money! The only thing that didn’t work was the missile launcher. The German’s solved this problem by using a high velocity gun but the American’s wedded to the Shillelagh ran the XM803 into further fiscal nightmares. Both MBT-70 spin offs were destroyed by the oil shock and both Armies launched supposedly low cost, simple projects to develop a new evolutionary tank from their 1950s designs. Beyond Shillelagh where in all this is evidence that the tank was no good? If there was no Vietnam War then the M70 Marshall tanks would have crushed the Iraqi Army just as quickly as the M1 Abrams tanks (probably quicker as they had better operational mobility.

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The XM150 and Shillelagh were the biggest culprits but even when it came to firing conventional 152mm munitions there were other problems, particularly with the combustible casing. And the drivers station may have worked but it never worked very well, and supposedly, nor did the difficult to operate 20mm anti-aircraft cannon. Regarding the MBT-70 performing better than the Abrams, it was years before new composite armors, lower-cost electronic systems, and a new generation of high-performance APFSDS ammunition, all of which would have had an effect on future armor development. How the MBT-70 would have changed in the face of such developments I don't know, but I highly doubt the end result in 1991 would be better than the M1A1HA.

Abraham Gubler said:

It was proven on hundreds of thousands of Citroens DSes. Pretty hard to improve on that... It’s another myth to claim that the MBT-70 was held back by its suspension or that it is unreliable and too much of a maintenance burden. Certainly compared to what you need to go through if a torsion bar breaks hydro-pneumatic suspension is a god send. Since maintenance of hydro-pneumatic suspension is mostly just changing the fluids and seals it’s not much different to maintaining tank transmission, brakes and the turret hydraulic systems. But heah lets not let facts intrude on ‘ess dif-er-ent ‘n I dona like et’ opinioning...

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A car and a 50 ton tank expected to operate on all terrain are hardly comparable. The suspension was bound to encounter some resistance among tankers and officers and there were certainly some legitimate reasons for their concern. Reportedly the hydropneumatic suspension used on the S-tank and Type-74 is described by their crews as a pain in the ass to maintain. Correct me if I am wrong but if a hydraulic line was to break the crew is out of luck. I have no problem with how radical any of the new features were, but some obviously did not work as they should have.

Abraham Gubler said:

Will an RPG-7V (85mm HEAT) penetrate the frontal armour of an MBT-70 or similar spaced armour tank? Nope. It won’t penetrate the frontal armour of an M1, CR, Leopard 2, etc with chobham armour, either. So what’s the difference? Ahh advanced tandem warhead anti-tank launchers that just happen to have the letters RPG in the name and the like... OK got me there... Semantics wins another debate... But this is all very immaterial the MBT-70 with spaced armour would never be driving around the 21st century battlefields. Maybe the M70A3 Marshall with DU composite armour would be...

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The MBT-70 would require a rather extensive redesign in order to incorporate Chobham or a similar composite armor. This or a new MBT would certainly be developed, but either way the end result was a significantly different design. Obviously any MBT-70 or tank developed from it would have better armor but the base design simply wouldn't match the Abram's survivability in Iraq, which was a point of discussion far earlier.

Abraham Gubler said:

Sure but you’re more than willing to degrade their efforts until someone calls you out over it. It’s easy to jump on the bandwagon and throw stones at fallen giants. But projects can fail for many reasons and most are not associated with engineering.

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No, I was not degrading their efforts. I just commented that some features, mainly the drivers position, seem foolish in retrospect. Thinking about the 20mm cannon, that seems not foolish, but was simply not effective enough with the technology of the time. In the end it just added another layer of mechanical complexity to a tank already very costly and suffering from problems with it's primary armament.

Colonial-Marine said:

Don’t mistake ripping your arguments apart as somehow an attitude of superiority. You are the one making the unsupported statements and offering these opinions. I’m not turning around and saying “you’re wrong, you’re wrong, I’m better than you...” etc. I’m just showing where you are wrong and providing the facts to prove it. I’m also calling you out on your simplistic and unjust reasoning that has lead you to these statements. This may not be pleasant for you but it certainly isn’t personally motivated.

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You seem to be convinced the MBT-70 was a machine that failed only due to cost and if it had entered service would have been a superior outcome to what actually occurred. This simply wasn't the case and it is was probably a good thing the MBT-70 never worked out, even though it was a useful program in other ways. In the end many of the subsystems simply were not successful or overcomplicated, even if they technically worked like the drivers turret.

Couple of frivolous points :

Just curious, but given the historic price as $1.5mill what would the relative current price be?

I normally consider the US as good at naming weapons systems, Thor, Raptor, Phantom, Sidewinder, Patriot, et al, but Shillelagh?!?!?! Why name a ground breaking, advanced weapons system (if ultimately flawed) after and Irish combination walking stick and club?

BTW Smurf, Thank you for the info, aft years of expecting the driver to have duck whenever the gun trained to the left I get it. Having to allow for the drivers movements must of consumed space in the turret?

Multiply by about 10, I guess, remembering my starting salary!
Given that, whatever the armour, a mine or a shell may take a track off, that is an expensive piece of kit.

Roll on the rise of the hover tank ;D!!!

rickshaw said:

Abraham, have you ever driven an armoured vehicle? You are of course a trained tank driver, afterall, you speak so authoritatively. I've discussed the MBT-70 with someone who actually drove one during the trials. He was rather uncomplimentary about its innovations. I'll take his word over yours.

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Rickhsaw at no stage in any of my posts here on the MBT-70 thread or elsewhere have I attempted to validate my comments by reference to some experience I have and that others may have and left it at that. I am intimately familiar with a range of tanks and AFVs and have had service experience with them as well. However that is not at issue here.

Rather than reduce this to an ‘I know better’ argument because you have some second hand association with someone who once drove this tank you should actually address the points. If you passed on my comments about vision height, rearwards driving, lateral displacement, etc to your tank driving friend you would probably find him nodding his head. I have also made it clear that the MBT-70 driver in turret position has a range of problems but unlike you I’ve correctly identified the source of the problem rather than some wishy-washy reference to “subconscious visual cues”.

Further when any new weapon system is introduced the Army has to manage a phenomenon where old soldiers trained to operate the old style weapon can’t adjust to the new one without extensive retraining. Whereas new soldiers training only on the new weapon system have no problem in using it.

rickshaw said:

There is a reason why they used to place the vehicle commander at the highest point of the vehicle, Abraham. Putting someone on the same level, in front of him, robs him of the advantage that position conveys. This is one reason why most tankers are very critical of moves to place the commander in the hull.

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The point is not the relative heights of the commander’s seat and that of other crewmen but the height of the commander’s field of view. In the case of the MBT-70 the commander has a ‘hunter-killer’ panoramic periscope sight with a full uninterrupted field of view around the vehicle. The commander’s back up vision blocks are low to the roof of the hull but this is just a design choice. In the preceding MBT(MR) they were raised above the roof height and had an unblocked field of view.

rickshaw said:

See my point above. Yes, there are plenty of other objects. None are as big or in the same position of the driver's position on the MBT-70. It is in a critical quadrant of the commander's vision. It prevents him from having that magic 6400 mil view. Therefore it is less than optimum.

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This is plainly wrong. The turret roof obscurants on the M1 Abrams are far more excessive than on the MBT-70 including for the fields of view of both the CITV and the commander’s cupola. The low level of the periscopes on the MBT-70 are probably to do with the changed crew workloads of the rotating driver’s pod. As the commander is freed from needing to assist the driver and now equipped with a panoramic sight linked to the fire control system this would be his primary closed hatches observation system rather than the cupola with the Patton tank. As the driver has a much better field of view they can also take on the loader’s role of local situational awareness and protection. Though this is just informed speculation.

rickshaw said:

That is your opinion. I beg to differ. "Cost" was a convenient excuse. If the US Army had really wanted the MBT-70 it would have found the dosh to pay for it. The reality was that it was too advanced for the technology of the day and so represented a failure. It was a case of technological over-reach by pushing the envelope too hard. Something the US military has proven very prone to.

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This isn’t just my opinion. If you bother to read any of the sources from the time you would notice Congress complaining about the five times increase in cost and the Army desperately trying to develop a low cost version, the Vietnam War, etc, etc. It may not support this argument you seem to have invested so much self esteem into but that’s your problem.

Colonial-Marine said:

A car and a 50 ton tank expected to operate on all terrain are hardly comparable. The suspension was bound to encounter some resistance among tankers and officers and there were certainly some legitimate reasons for their concern. Reportedly the hydropneumatic suspension used on the S-tank and Type-74 is described by their crews as a pain in the ass to maintain. Correct me if I am wrong but if a hydraulic line was to break the crew is out of luck. I have no problem with how radical any of the new features were, but some obviously did not work as they should have.

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The difference between a car and a tank is why the MBT-70 would not be running on an interchangeable suspension unit as a Citreon DS! Of course it would be bigger, more resilient and so on. Considering every tank uses the same kind of suspension type as that first seen on cars be they torsion bars, springs, hydro gas, etc this is not a strong argument to make.

Like I said before more maintenance for the crew but less workshop work for major repairs. In the greater scheme of things of running a tank force at war this is an impost on the crew that makes for a more efficient overall force. Because it means more tanks will be available to actual units and in the field shooting at the enemy than in the park waiting for new torsion bars.

Though I’m not familiar with the exact nature of the MBT-70’s suspension design it can be mounted externally to the hull. Since all tanks of this time relied on hydraulics for turret rotation (and the M1 does to this day) the increase in risk is marginal.

Colonial-Marine said:

The MBT-70 would require a rather extensive redesign in order to incorporate Chobham or a similar composite armor. This or a new MBT would certainly be developed, but either way the end result was a significantly different design. Obviously any MBT-70 or tank developed from it would have better armor but the base design simply wouldn't match the Abram's survivability in Iraq, which was a point of discussion far earlier.

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No it wouldn’t. Spaced armour tanks have shown an easily ability to be converted to Chobham type layered armour. Case in point being the M1 itself (originally designed as space armour) the Leopard 2 and the Merkava Mk 3. Chobham armour is very similar in design to spaced armour being two pieces of metal with various layers in between. Since the interior mould line of the turret doesn’t change this means a simple modification.

Colonial-Marine said:

You seem to be convinced the MBT-70 was a machine that failed only due to cost and if it had entered service would have been a superior outcome to what actually occurred. This simply wasn't the case and it is was probably a good thing the MBT-70 never worked out, even though it was a useful program in other ways. In the end many of the subsystems simply were not successful or overcomplicated, even if they technically worked like the drivers turret.

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No I’m not. I’m just repeatedly making the point that the MBT-70 should NOT be written off as a lemon or as a technical failure. It also offered a range of design advantages over what came later when one balances the differences in technology available at certain times.

What is significant is during the 1970s if the Soviets had ever launched an attack on West Germany then both the US and German Army would have been a lot better off with MBT-70s rather than M60s and Leopard 1s. They would also be better off up until 1989 with 10-20 years of MBT-70 production for >12,000 units rather than the <4,000 Leopard 2s and M1s they actually have had. Considering the crucial year for a central front war was 1984 (when the Soviets came closest to launching an attack since 1961) the MBT-70 would have provided a much more enhanced NATO force than not having the MBT-70.

Abraham Gubler said

They would also be better off up until 1989 with 10-20 years of MBT-70 production for >12,000 units rather than the <4,000 Leopard 2s and M1s they actually have had

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Is that true, at $1.5M each at 1960s prices?
$18 billion dollars not allowing for price increases (5-fold, you said?) across the 1970s oil crisis.

Though this is just informed speculation.
Though I’m not familiar with the exact nature of the MBT-70’s suspension design

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just like other enthusiasts,
(and prepared to deal with USS Saratoga as a hybrid, though that is another story.)

But

you should actually address the points

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What about the cost being due to over-complex design"?
To regard any tank as successful, it should surely be possible to point to the service life of many examples?
To achieve that, some army has to buy it. To that extent, MBT-70 failed.
Why was it not bought?
Because it was too expensive.
Why was it too expensive?
Because its design made it so.

If you disagree, I shall be interested to know where you believe the expense came from with this tank, compared to others, if it was not the design features.
Can you please manage to do that without so many (or any) comments such as

seem to have invested so much self esteem into but that’s your problem.

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If you bother to read

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because you have some second hand association with someone who once drove this tank

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some wishy-washy reference to

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Semantics, to which you seem to have an unaccountable objection, relates to meaning in language.
Ad hominem phrases such as the above tend to obscure your meaning, and irritate your readers, not just the person you are replying to, though you are doing better than in your earlier posts.

smurf said:

Semantics, to which you seem to have an unaccountable objection, relates to meaning in language.
Ad hominem phrases such as the above tend to obscure your meaning, and irritate your readers, not just the person you are replying to, though you are doing better than in your earlier posts.

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The point of your contribution is? Since you’ve made no real input to the actual MBT-70 “a dodged lemon or unrealised battle king” discussion it would appear you are trying to be some kind of white knight rushing to the defence of the hard done by…

Please realise that the internet is an international phenomena and therefore encompasses many cultures with different standards in discussion. I may throw in a few jibes here and there but that’s just natural for an Australian. Many of my compatriots would probably judge me as being very gentle. Other cultures like the Israelis would consider my comments downright soft to the point of emasculation.

The point is please don’t fill up this thread with an attempt to go toe to toe with someone you don’t like. If you have a problem with my language complain about it in the appropriate forum rather than cloud this thread with even more pointless posts.

AG asks:

The point of your contribution is?

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Repeated, but not answered:

AG said
Quote
The problem was not the design but cost.
But the reason for the cost was the design - in one word, over-complex.

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Quote
you should actually address the points
What about the cost being due to over-complex design"?
To regard any tank as successful, it should surely be possible to point to the service life of many examples?
To achieve that, some army has to buy it. To that extent, MBT-70 failed.
Why was it not bought?
Because it was too expensive.
Why was it too expensive?
Because its design made it so.

If you disagree, I shall be interested to know where you believe the expense came from with this tank, compared to others, if it was not the design features.
Can you please manage to do that

Click to expand...

If one does not want to be owned in a debate, one should probably stop trying to argue with propositional fallacies like:

Why was it not bought?
Because it was too expensive.
Why was it too expensive?
Because its design made it so.

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This totally ignores any other budgetary concerns at the time, like for instance the Vietnam war.

Why was it not bought?
Because it was too expensive.
Why was it too expensive?
Because its design made it so.

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That is not a propositional fallacy. It is a statement of opinion.
If true, it is unaffected by the Vietnam war, unless you believe that in more peaceful times, more expensive military equipment can be bought. If false, there are other factors, which I have asked for.

If you disagree, I shall be interested to know where you believe the expense came from with this tank, compared to others, if it was not the design features.

Click to expand...

Is MBT-70 a particular victim of the Vietnam war?

Further, it was a brief quote to indicate where my point was made, its chief substance, and the fact that it was unanswered.

If one does not want to be owned in a debate,

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what does that mean, please?

smurf said:

That is not a propositional fallacy. It is a statement of opinion.
If true, it is unaffected by the Vietnam war, unless you believe that in more peaceful times, more expensive military equipment can be bought. If false, there are other factors, which I have asked for.

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http://en.wikipedia.org/wiki/Affirming_the_consequent said:

Affirming the consequent, sometimes called converse error, is a formal fallacy, committed by reasoning in the form:

If P, then Q.
Q.
Therefore, P.
Arguments of this form are invalid, in that the conclusion (3) does not have to follow even when statements 1 and 2 are true. The simple reason for this is that P was never asserted as the only sufficient condition for Q, so, in general, any number of other factors could account for Q (while P was false).

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Is MBT-70 a particular victim of the Vietnam war?

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Yes, much like F-22 or airborne laser are victims of the WoT because suddenly there are insufficent funds and procurers have to axe some programs in favor of others within the budgetary frame.

Further, it was a brief quote to indicate where my point was made, its chief substance, and the fact that it was unanswered.

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It has been answered both by Abraham, and by me. If that's not good enough for you then too bad.

smurf said:

Further, it was a brief quote to indicate where my point was made, its chief substance, and the fact that it was unanswered.

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This point was addressed earlier in this discussion before you waded in. But to put the issue to bed, perhaps I should refer you to:

"AN EXAMINATION OF THE XM-1 TANK SYSTEM ACQUISITION PROGRAM IN A PEACETIME ENVIRONMENT" by Lt.Col. Glen Williams written in 1974 that provides an analysis of the downfall of the MBT-70 program. You will find it refers to cost and multi-national incompatibility rather than the popular assumptions generated decades later.

I regret you have misunderstood my point.
Abraham said

The problem was not the design but cost.

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But the MBT-70 was a very complex tank, and as a result very expensive.
I do not dispute that during its lifetime other factors than design affected costs, but many of these would have impacted similarly on other projects or alternative tanks. Shortage of funds due to money spent elsewhere does not itself increase costs. It may make even a cheap design unaffordable. When the MBT-70 was cancelled, cheaper alternatives were sought by simplifying the design. Of course, if the price of titanium increases more than the price of steel, the cost of the MBT-70's lightweight escape hatch goes up relative to a simple steel one, as does the price of the tank. But the cast titanium hatch cover was a necessary design feature.
The MBT-70 had many advanced engineering features and the development engineers made them work, either sooner or later in its development, all credit to them. But the tank by then was even more complex than the initial design, and not within the planned weight limit (though by no means the only tank for which that was true). But the end result was that the tanks were expected to cost $1.2M each, and the powers that be thought that a different adequate tank should be designed for much less. Perhaps a case of the best being the enemy of the good. Meanwhile, a potential enemy was managing to equip its army with large numbers of tanks, more effective than those in service in US and German armies (or else why seek replacement?). So, in my view, engineering success with individual components accepted, the MBT-70 cannot be regarded as a successful design, not even making it into service.

You are still treating my four lines as though they are a proposition in formal logic.
They are not, and were not so intended. They were intended simply to emphasise the earlier single line
What about the cost being due to over-complex design"?

If P (= too expensive) then Q (= not bought)
Q (not bought)
Therefore, P (too expensive)
Clearly that is false. It might be not bought because the colour was disliked.
But there is no additional term X (= too complex) in the formal fallacy "affirming the consequent". I regret you have misapplied that, too.
Do you maintain that design has no influence on cost? Nor on acceptability to potential customers?
I maintain "too complex" contributed heavily to "too expensive" which in its turn contributed heavily to "not bought". But I don't maintain that that sequence is incontrovertible because of the rules of formal logic. I put it forward empirically as a probable scenario, quite frequently observed, to be negated in the case of the MBT-70 by pointing to compelling evidence to the contrary. I haven't seen much yet. Nor did Congress at the time.

smurf said:

But the MBT-70 was a very complex tank, and as a result very expensive.

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Acceptable forum use words cannot describe what I think of your recent commentary. Obviously you haven’t bothered to read the actual post discussion and have just waded in with a selective quote taken out of context and manipulated it semantically to make a completely pointless point.

The entire discussion has been was the MBT-70 cancelled because its design concept was ‘foolish’ or faulty (things like the rotating driver’s seat) or because it cost too much for congress at that time. Of course the design leads to cost. The more capability you design in the more cost. This has been an issue in defence since the first cave man suggested clubs can be improved by a bit of work on them rather than just picking up sticks from the ground. Cost gives you capability and it’s an eternal tradeoff between the two to realise said capability.

But the whole debate has been about the point of project failure being either rejected for its technical design (too innovative or didn’t work) or rejected for its cost (all that stuff was good but it added up to too much). To semantically turn the abbreviated language used to describe one of these contentions into the other is either duplicitous or completely ignorant of what the rest of us have been discussing. So ‘smurf’ off!

Abraham Gubler said:

rickshaw said:

Abraham, have you ever driven an armoured vehicle? You are of course a trained tank driver, afterall, you speak so authoritatively. I've discussed the MBT-70 with someone who actually drove one during the trials. He was rather uncomplimentary about its innovations. I'll take his word over yours.

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Rickhsaw at no stage in any of my posts here on the MBT-70 thread or elsewhere have I attempted to validate my comments by reference to some experience I have and that others may have and left it at that. I am intimately familiar with a range of tanks and AFVs and have had service experience with them as well. However that is not at issue here.

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Abraham, you don't appear to have attempted to validate your comments at all. You attempt to be the authority on a vehicle you've (a) never seen; (b) never driven; (c) never crewed. I base my comments on what I've read in books and magazine articles plus the comments of an ex-US Army tanker who actually worked on the MBT-70 as well as my own military experience. As I said, I'll take my sources over your personal viewpoint. Your welcome to your opinion but please don't try and claim some authority which you don't have. Like many non-military armchair theorists, you undervalue personal experience and overvalue your own opinion.

The vehicle is an interesting but ultimately failed experiment. If had worked, they wouldn't have abandoned it. You'd have seen its major technologies being applied in tanks today. We aren't. QED.

Abraham, reading through your comments (which I did as the debate progressed) I found
1. several apparently self-contradictory statements between your posts
2. that you seemed frequently to have lost sight of the interaction between the complexity of design features and their cost - in particular, that extensive time spent making features work which did not do so as first designed contributes heavily to cost
3. that you ignore others points (eg Robunos point about the basic reason for putting the crew in the turret, which leads to the complex driving arrangements) replacing them with your own (that it lowers the roof - so it did, but that was secondary).
4. that you seem to expect discussions to conform to your ideas of how they should go, and deal with others' points aggressively and rudely if that doesn't happen. That you believe your fellow-countrymen to be equally rude is no excuse. I have met polite and gentlemanly Australians.
5. your statements are not clear and accurate. When I ask for clarification to be sure of what you do mean, you dismiss that as "semantics" - a subject it might benefit you to study. For example

Cost gives you capability

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is not always true, nor the same as "capability costs." I suspect you meant the latter.

the whole debate has been about the point of project failure being either rejected for its technical design (too innovative or didn’t work) or rejected for its cost (all that stuff was good but it added up to too much).

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My point is that this is a false distinction.
A good design process first establishes the user's requirements, any constraints (overall cost, completion time, then details such as maximum weight or dimensions etc) and then seeks to meet the requirements within the constraints.
(If for some reason the users' requirements cannot be established clearly, then the project design team must set up their own to work to, informing the users and asking for their acceptance of them. That may of course produce some clarification.)

The MBT-70 programme failed (in my view - you may disagree) not because of engineers' failure to solve technical problems, but because of a fatally flawed design review process, which allowed costs to escalate in pursuit of innovative design solutions which may or may not have been real requirements, particularly at their likely price.
But that must be laid at the door of the senior design project management. (Though reconciling the views and needs of two nations was a very hard task at which few have succeeded.)

I believe this point to be one worth making, clearly and explicitly, even if it doesn't fit the simplistic dichotomy between the two views you seek to decide between.

Having made it, I will now meet your last request. I'm sure you wouldn't want my capability for invective turned in your direction.

rickshaw said:

Abraham, you don't appear to have attempted to validate your comments at all.

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Then you aren't reading my posts. They have been point after point of explanation of MBT-70 capability benchmarked to standard tank crewing practice. This the form of validation I have used over and over again in this thread in relation to a range of MBT-70 issues. Driver’s position, commander’s view, hydro pneumatic suspension, armour and frontal profile, etc. In each case I have explained how its system works in relation to how other more conventional tanks work and extrapolated the advantages and disadvantages of the difference MBT 70 configuration.

What you have done is claim that I am wrong without contending a single one of these explanations and referenced your opinion to a single unsupported claim that you knew a MBT 70 trial crew member and that he just didn’t like it. You’ve also claimed that I don’t have any practical knowledge of tanks which is frankly wrong but because I respect the open opinion forum nature of this site I won’t try and flood this discussion with my tank references.

rickshaw said:

The vehicle is an interesting but ultimately failed experiment. If had worked, they wouldn't have abandoned it. You'd have seen its major technologies being applied in tanks today. We aren't. QED.

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Not at all. Much of the MBT 70s design ended up in the M1, like the high power to weight engine and night fighting sights. Many of the MBT 70’s analogue solutions have been made redundant by digital technology but the basic concepts live on (crew in hull is the new crew in turret). As I mentioned before the only reason we haven’t seen a crew in hull tank is more to do with finances than want of effort. The US Army has produced multiple prototypes and test beds from 1970 to now for such light, medium and heavy tanks but for various financial reasons haven’t received a production order.

Since this thread has just been reduced to a semantical mud-slinging match I don’t see much point to it. If Rickshaw can actually come up with a single fact or point of analysis – and he hasn’t since his ridiculous ‘commander’s view is obstructed’ comment – then I don’t see much point in continuing this.

smurf said:

3. that you ignore others points (eg Robunos point about the basic reason for putting the crew in the turret, which leads to the complex driving arrangements) replacing them with your own (that it lowers the roof - so it did, but that was secondary).

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Since you’re such a student of this thread perhaps you could tell us all what date it was that Robunos made the quote about NBC protection? Ahh several days before I even entered this discussion and completely unrelated to why I entered this discussion. However I very much doubt there is a single tank designer or armoured vehicles analyst in this world who would considered lowering roof height and reducing frontal exposure as ‘secondary’. Certainly something Hunicutt would never say. Frontal exposure is the most crucial part of tank design in an anti-tank weapons environment.

smurf said:

The MBT-70 programme failed (in my view - you may disagree) not because of engineers' failure to solve technical problems, but because of a fatally flawed design review process, which allowed costs to escalate in pursuit of innovative design solutions which may or may not have been real requirements, particularly at their likely price.

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As I made it clear in my last post, yes, yes and yes. But the argument at hand was a simpler one between the historically supported case of the MBT 70 being cancelled because of high cost – which was brought about by the very failures in project management you are talking about (thanks for that Sherlock)– and that it was cancelled because the tank didn’t work as a combat system. Nothing you have contributed changes that question. You’ve just distracted immensely from it and created yourself a pedestal to complain about my harsh treatment of some people offering comments that don’t match the facts.

smurf said:

Having made it, I will now meet your last request. I'm sure you wouldn't want my capability for invective turned in your direction.

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If it’s anything like your ability to identify an argument then it wouldn’t worry me too much.

Re: MBT 70 anti-aircraft version

JAZZ said:

The Gepard (2x35mm) as we know it was one the other was the Matador (2x30mm) see attached.

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Here is another picture of the Rheinmettal Matador. This one has those rather large turret side hatches open. Perhaps for reloading or even shell ejection?

MBT-70

Source:
http://www.militaryphotos.net/forums/showthread.php?176030-Why-polictians-suck-%28cool-photos%29

Line drawings of MBT-70.

Sources:
http://www.fprado.com/armorsite/mbt_70.htm
http://www.valka.cz/clanek_11743.html
http://www.polycount.com/forum/showthread.php?t=69969

You would wonder how the MBT 70 would have evolved if this had entered service before it:

http://www.youtube.com/watch?v=fJ7jwcHcM3I&feature=player_embedded

On the other hand, if it had, the MBT concept in general might not have existed at all.

They would also be better off up until 1989 with 10-20 years of MBT-70 production for >12,000 units rather than the <4,000 Leopard 2s and M1s they actually have had.
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Is there any factual reference for plans for a production run of 12,000 MBT-70's or is this just speculation? Does anyone have a reference for the actual planned joint US/FRG production goals?

A run of 12,000 MBT70s would suggest that the US Army had been completely re-equipped with them. A doubtful possibility, particularly when the vehicle itself was of such questionable abilities.

I came across the Congressional hearings on the Army Tank Program which lead to the projected budget request for the MBT-70 program being $8.6 Billion in 1970 $'s. With the unit cost at that time being quoted as $1 Million per tank, that equates to 8,600 MBT-70's for the US Army being planned. The unit cost quoted by the FRG at the time they pulled out of the project was $1.2 Million US per tank. Keep in mind that the FRG was planning on building their own version, with different engine, main gun, every bolt and fastener converted to metric, and German optics and fire control. Factor these changes into a much smaller production run and of course the costs would be higher for the FRG version.
Once the FRG dropped out, the US version's unit cost also increased greatly (to the previously quoted $1.5 Million) because of reduced economy of scale on the common components plus R&D costs spread over a smaller production run. So it seems 12,000 MBT-70's total between both countries may have been a realistic total.

KPz 70 - German version of that tank - was supposed to get German engine, but not new main gun (at least not from the start). Fire control system was already consisted of American and German subsystems. Also, after the long discussions during early phase of project, it was agreed (at high level ofSecretary of Defense and Federal Minister of Defence) that all fasteners/joints would be metric.