StuG III Thread (and also other German vehicles I guess)

[Scolopax]

1 hour ago, XDrake said:

Is there actually any documentation on the sideskirts that are portrayed on most model kits and video game models of the E-100? If thats the case what were the supposed armored values? I think its also pretty much an innovation in german armour design in WW2. Havent seen any addon/modular armor on other WW2 tanks.

 

example here:

  Hide contents

Model kit:

WoT:

War Thunder:

 

 

There are photographs and drawings in the Panzer Tracts volume on it and the Maus.  Link with pdf download below:

 

On 7/4/2018 at 9:30 AM, Walter_Sobchak said:

http://b-ok.org/s/?q=panzer+tracts&yearFrom=&yearTo=&language=&extension=&t=0

 

WoT has the skirts' armor value at 60mm, but I can't say if that's an official number.

 

[Legiondude]

13 hours ago, XDrake said:

Is there actually any documentation on the sideskirts that are portrayed on most model kits and video game models of the E-100? If thats the case what were the supposed armored values?

 

12 hours ago, Scolopax said:

There are photographs and drawings in the Panzer Tracts volume on it and the Maus.  Link with pdf download below:

 

WoT has the skirts' armor value at 60mm, but I can't say if that's an official number.

I don't see anything in Panzer Tracts 6-3 about those plates thicknesses. It's possible they weren't armor steel and considered semi-disposable, like the plates on the Tigers

 

Skimming Google, there looks to be a US Intel profile of the armor on a Roblox wiki of all things, but it only lists the armor angles. That angle measurement may have been misinterpreted in the decades following, as this more modern image assumes 60mm armor thickness instead of 60 degrees angle on the upper side. This profile from a Russian publication seems to suggest in the ballpark though, at 55mm.

Looking in Special Panzer Variants by Spielberger, there doesn't seem mention of the plates thicknesses either. There could be information gleaned from the blueprints though. But the originals were lost or buried in the archives(AFAIK, Yuri Pasholok does have one of the design prints for the turret assembly though). As Spielberger tells, after the war, one of the guys behind the E-100's assembly was roped in Operation Paperclip and offered to recreate the blueprints from memory, which is this thing. It's large, but still too low resolution to properly read it. Luckily, Spielberger has a copy in his book spread over two pages and is quite legible. We can utilize the front or rear image faces to scale things properly and try to get an estimate at least to the bottom lip thickness of the side plates.

 

tl;dr - Running an estimate on the forward face, I got an estimate on the lip just before it meets the front corner of the hull of about 71mm. Running a separate estimate based on the top view, with the hull width run against the plate thickness that is vertical and parallel to the hull, I got 68mm. I could probably get more specific if I had a better copy of the plans, or a more precise measuring tool than MS Paint's coordinate system assisted with some number crunching in Excel.

[XDrake]

14 hours ago, EnsignExpendable said:

The Americans had addon armour developed for the M10 GMC. It was trialled but never deployed IIRC.

Did not know that, but addon armor on the M10 doesnt sound reasonable since its probably not supposed to take fire from anything larger than infantry rifles anyways

 

14 hours ago, Scolopax said:

 

There are photographs and drawings in the Panzer Tracts volume on it and the Maus.  Link with pdf download below:

 

 

WoT has the skirts' armor value at 60mm, but I can't say if that's an official number.

 

I did some search on Google myself and the specific values seem to vary.

 

1 hour ago, Legiondude said:

 

I don't see anything in Panzer Tracts 6-3 about those plates thicknesses. It's possible they weren't armor steel and considered semi-disposable, like the plates on the Tigers

 

Skimming Google, there looks to be a US Intel profile of the armor on a Roblox wiki of all things, but it only lists the armor angles. That angle measurement may have been misinterpreted in the decades following, as this more modern image assumes 60mm armor thickness instead of 60 degrees angle on the upper side. This profile from a Russian publication seems to suggest in the ballpark though, at 55mm.

Looking in Special Panzer Variants by Spielberger, there doesn't seem mention of the plates thicknesses either. There could be information gleaned from the blueprints though. But the originals were lost or buried in the archives(AFAIK, Yuri Pasholok does have one of the design prints for the turret assembly though). As Spielberger tells, after the war, one of the guys behind the E-100's assembly was roped in Operation Paperclip and offered to recreate the blueprints from memory, which is this thing. It's large, but still too low resolution to properly read it. Luckily, Spielberger has a copy in his book spread over two pages and is quite legible. We can utilize the front or rear image faces to scale things properly and try to get an estimate at least to the bottom lip thickness of the side plates.

 

tl;dr - Running an estimate on the forward face, I got an estimate on the lip just before it meets the front corner of the hull of about 71mm. Running a separate estimate based on the top view, with the hull width run against the plate thickness that is vertical and parallel to the hull, I got 68mm. I could probably get more specific if I had a better copy of the plans, or a more precise measuring tool than MS Paint's coordinate system assisted with some number crunching in Excel.

Nice job. According to this post from the War Thunder website your estimates seem to be about right. They state 75mm. They also have some interesting pictures of their recreation process.

[Wiedzmin]

[heretic88]

So basically this means, that the heavier Leo-1A2 turret only had somewhat thicker side armor... Quite unimpressive. Leopard-1 was an incredibly poorly armored tank. Strange that they didnt even try to make it proof against BR-412D, which though not particularly good at penetration (basically ww2 tech), had incredibly devastating behind armor effect.

[Xlucine]

Protection from 100mm APHE isn't to be sniffed at, that's the same level as the chieftain specification - a pretty big jump from leopard 1 armour

[Walter_Sobchak]

15 hours ago, heretic88 said:

So basically this means, that the heavier Leo-1A2 turret only had somewhat thicker side armor... Quite unimpressive. Leopard-1 was an incredibly poorly armored tank. Strange that they didnt even try to make it proof against BR-412D, which though not particularly good at penetration (basically ww2 tech), had incredibly devastating behind armor effect.

 

It wasn't meant to be well armored.  They wanted firepower and speed.  Given the limitations of 1960's era armor technology and the strategic situation West Germany faced at the time, I think it was a pretty reasonable choice.  I've always thought the Leopard I was a pretty good tank for it's time.  I would have picked it over a Chieftain in most situations.  Not sure I would have picked it over an M60 though.  

[Jeeps_Guns_Tanks]

On 8/10/2018 at 6:32 PM, EnsignExpendable said:

The Americans had addon armour developed for the M10 GMC. It was trialled but never deployed IIRC.

 

Yeah, that's what all the bolts on the hull and turret were for. I wonder why they never tried it in combat?  Maybe because the TD people wanted more mobility, not less, and thought the M10s main flaw was it was to slow. 

 

[Walter_Sobchak]

35 minutes ago, Jeeps_Guns_Tanks said:

 

Yeah, that's what all the bolts on the hull and turret were for. I wonder why they never tried it in combat?  Maybe because the TD people wanted more mobility, not less, and thought the M10s main flaw was it was to slow. 

 

 

That would be my guess too.  Although just to clarify, when you say TD people, that refers to the leadership.  The guys actually driving these things around were quite happy to have whatever armor they could get.  I think there was even a TD battalion that refused to switch from M10 TDs to M18 Hellcats because of how little armor they had.  I'll have to look up where I read that.

[Jeeps_Guns_Tanks]

38 minutes ago, Walter_Sobchak said:

 

That would be my guess too.  Although just to clarify, when you say TD people, that refers to the leadership.  The guys actually driving these things around were quite happy to have whatever armor they could get.  I think there was even a TD battalion that refused to switch from M10 TDs to M18 Hellcats because of how little armor they had.  I'll have to look up where I read that.

 

Yeah, I read the same thing, I think it was in Yeide's tank destroyer book. 

[Walter_Sobchak]

1 minute ago, Jeeps_Guns_Tanks said:

 

Yeah, I read the same thing, I think it was in Yeide's tank destroyer book. 

 

Sounds about right.  Anyhow, I think the M10 is a pretty underrated vehicle.  It certainly had some flaws (no coax machine gun, manual turret traverse), but it was a pretty good can opener by the standards of 1943.  

[heretic88]

7 hours ago, Walter_Sobchak said:

 

It wasn't meant to be well armored.  They wanted firepower and speed.  Given the limitations of 1960's era armor technology and the strategic situation West Germany faced at the time, I think it was a pretty reasonable choice.  I've always thought the Leopard I was a pretty good tank for it's time.  I would have picked it over a Chieftain in most situations.  Not sure I would have picked it over an M60 though.  

Im not really sure what to think about the Leopard-1. Yes, it had great mobility, also good firepower. But that total neglect of armor... And its not just the protection-firepower-mobility triumvirate. For quite a long time, it didnt have a stabilizer, this somewhat negated its advantages in mobility. I have a soviet gunnery manual for T-62, and they acknowledge that the Leopard is very fast, but then strongly emphasize the lack of stabilizer, as an exploitable weakness. The night fighting ability of the Leopard until the PZB-200 was also quite deficient. At night, it actually had a 3 man crew, since the gunner didnt have any night sights, so he could do nothing at all. The commander now had to aim the gun, distracting him from his other duties. This is even worse than soviet tanks with their quite poor IR sights, where the commander at least could help with observation, at least for shorter ranges (~500m).

In my opinion, the Leopard was greatly inferior to the M-60A1. The american tank was slower, but actually had better cross country capability, had the best armor in the world until the appearance of the T-64 (fully 100mm APHE/APDS/APFSDS proof frontally). It also lacked stabilizer, but had much better night fighting ability. Probably it was also the best tank in the world in the 60s.

[Wiedzmin]

2 hours ago, heretic88 said:

Yes, it had great mobility

 

 

[SH_MM]

17 hours ago, Xlucine said:

Protection from 100mm APHE isn't to be sniffed at, that's the same level as the chieftain specification - a pretty big jump from leopard 1 armour

 

Yes, would be interesting to see a weight comparison between the two turrets. How heavy was the Chieftain's turret casting (without any other components)?

 

3 hours ago, heretic88 said:

The night fighting ability of the Leopard until the PZB-200 was also quite deficient. At night, it actually had a 3 man crew, since the gunner didnt have any night sights, so he could do nothing at all. The commander now had to aim the gun, distracting him from his other duties. This is even worse than soviet tanks with their quite poor IR sights, where the commander at least could help with observation, at least for shorter ranges (~500m).

 

Night fighting in the 1950s, 1960s and early 1970s was a horrible idea for all involved. As all IR sights of the era required an active source, it made the illuminating tank very easy to spot. Also the gunner still has to do his part of the job, it is not the case that the commander does everything. The commander just spots the target and instructs the gunner.

 

The reason why there is only one IR sight on the Leopard 1 are simple:

1. Unlike all other tanks of the era, the Leopard 1's gunner's sight was integrated into the rangefinder, making it impossible to directly integrate an IR sight into it. Therefore the gunner could only have a small auxiallary IR sight mounted to roof at best, which wouldn't provide enough effective range to spot targets at night - or the commander would have no IR sight.

2. The commander's task is to lead the tank, so he needs an IR sight. For the German army, mounting a short-ranged night vision system as used by the Soviet tank commanders or by the OB-23-A as usedd by the commander of the AMX-30 was not considered enough. There is a difference in doctrine, which is reflected in the fact that the Leopard 1 commander was provided with an independent sight (at first TRP, later PERI R12). The Leopard 1 commander  can - since the original production model - override the gunner's inputs and has fire priority. He also doesn't operate the roof-mounted MG. In other words you could say, that in the German opinion the tank commander is more of a gunner than in the opinion of tje US Army and Soviets.

 

In the end is a question of what you want: a good long range IR sight or two less capable systems? For the Leopard 1, the combination of B 171 II sight and XSW-30-U searchlight are said in German books to have a maximum range of 1,200 to 1,500 metres. That is a big difference compared to the M60's 1,000 metres and the TPN-1's 600-800 metres.

 

The PzB 200 and similar LLTV systems were the first optics that actually made it possible to fire at night withotu exposing yourself (or another tank of your company) to the enemy while aiming... and it actually outranged all Soviet IR systems.

 

3 hours ago, heretic88 said:

In my opinion, the Leopard was greatly inferior to the M-60A1. The american tank was slower, but actually had better cross country capability, had the best armor in the world until the appearance of the T-64 (fully 100mm APHE/APDS/APFSDS proof frontally). It also lacked stabilizer, but had much better night fighting ability. Probably it was also the best tank in the world in the 60s. 

 

The M60A1 has worse cross-country mobility given its weaker engine, lower suspension performance and greater weight. It also didn't have the best armor in the world, the Chieftain was the best protected tank at the time: it had a larger protected frontal arc: 45° instead of 30° ( ±  15°) from the turret centerline, a lower profile and thicker armor.

 

The M60 btw. is far from immune to 100 mm APHE round  (I don't even think we need to talk about 100 mm APDS and APFSDS rounds...):

 

 

The M60 is vulnerable to 100 mm AP at ranges similar to the Leopard 1, if you take into account the whole frontal 60° arc. The M60A1 is still more vulnerable than the early Leopard 2(K/PT), but probably about as good - maybe a bit better - armored than the Leopard 1A3, 1A4 and 1A1A1 on the turret. The real difference in armor protection is the hull, which isn't particular likely to be hit.

 

 

 

[SH_MM]

1 hour ago, Wiedzmin said:

 

 

And this shows what? Aside of the author being very much pro-Chieftain, the Leopard 1 is clearly faster at acclerating. This is a cross-country test, so all vehicle results will be closer than on flat surface. Given that the acceleration hasn't stopped at 500 m, it is a rather misleading table. The German military considered 400 m to be the minimum distance of tactical movement.

[Wiedzmin]

Book gives name of exercise, you can try find report, it's not "pro-chieftain" it's usual trials , real tank mobility have nothing to "max.speed" and all of that "max" values, so in real life there is no great advantage of Leo1 mobility over any western tank in cross-country, if i remember correctly this is one of many tests show that's is nothing "special" in Leo1 mobility. 

 

 

[SH_MM]

The author of the book is pro-Chieftain, the test results are not. These tests need to be put into a context, which the author doesn't do. He just says "look, Chieftain is only 7.4 seconds slower to 500 m" distance (when driving along a certain cross-country track), but in reality it matters how often the tank will need to drive 500 m, how much will it drive less and how often more than 500 m? What is the requirement? Being exposed for 5 to 10 seconds longer to enemy fire can be the difference between life and death. And acceleration cross-country is only small part of the overall mobility.

 

The source of the values is the Dutch exercise, in which they compared the Leopard 1 and Chieftain as potential successors for the Centurion. They ended up buying the Leopard 1 despite its lower armor protection and smaller gun calibre, because it proved to be better in several aspects such as reliability, fire control and mobility. The whole page of the book however is saying "the Dutch were wrong, their Inspector of Cavalry wanted the Leopard 1, he was so biased". It is rather common for British authors to find excuses for the poor state of British tanks. The Chieftain is unreliable? "It's the fault of NATO's multi-fuel requirements" (which were met by other, more reliable tanks at the same time). The Challenger 1 underperforms in CAT? "The rules of the event forced us to send the wrong unit to Germany, the other unit would have won the event" - meanwhile conscripts (!) in the Leopard 1 performed better. The Challenger 2E performs badly in the Greek trials? Well, they used the wrong propellant charges (even though the same propellant charges were used in Oman). 

 

Authors from other countries are biased just as well (there are lots of biased German books), but they usually don't have to invent their own theories about why their tanks didn't sell on the global MBT market.

[Bronezhilet]

Oh yeah those trials. Fun times!

 

Iirc the crews hated the Chieftain, but liked the Brits. 

[Wiedzmin]

1 hour ago, SH_MM said:

The author of the book is pro-Chieftain, the test results are not. These tests need to be put into a context, which the author doesn't do. He just says "look, Chieftain is only 7.4 seconds slower to 500 m" distance (when driving along a certain cross-country track), but in reality it matters how often the tank will need to drive 500 m, how much will it drive less and how often more than 500 m? What is the requirement?

well, lets make it simple 

 

1 squad Chieftan

1 squad Leo1

1 squad M60A1

 

how fast each squad can make a march cross-country  at 300km ? 500km ? 

 

I'm not trying to argue with you or with somebody. 

 

all this "armour protects only from rain and wind, but mobility!111" looks also like 

 

but what we have at the moment ? british "pro-Chieftain"(i understand the fact that all nations have theirs idiotic "national pride") report(about real test) and what report from german side about Leo1 vs any western tank ?

 

 

[Walter_Sobchak]

Unfortunately the link is now dead, but a while back there was an interview of an Iranian tanker from the Iran/Iraq war.  He served in both Chieftain and M60 tanks.  When asked which he and his fellow soldiers preferred, he said M60 unequivocally.  The reason was that the M60 was much more reliable.  

[Collimatrix]

5 hours ago, Wiedzmin said:

Book gives name of exercise, you can try find report, it's not "pro-chieftain" it's usual trials , real tank mobility have nothing to "max.speed" and all of that "max" values, so in real life there is no great advantage of Leo1 mobility over any western tank in cross-country, if i remember correctly this is one of many tests show that's is nothing "special" in Leo1 mobility. 

 

 

 

The Leo 1 beat the snot out of other Western MBTs in terms of practical mobility in its day.  There are some tests that show that Chieftains were almost as good, but it's trivial to set up a test where the primary limitation on average speed is avoidance of obstacles that are hard to see.  In that case, all drivers would need to slow down enormously so they could see the obstacles (hidden by tall grass, for instance), and all tanks tested would have the same practical mobility.

But on more representative courses, the Leopard 1 has several advantages over contemporary Western MBTs in addition to its higher power to weight ratio. 

 

The steering on the Leo 1 was better.  The Leo 1 had a two-speed steering drive and a differential lock.  This meant that the Leo 1 had two steering radii per transmission gear, which meant that the driver could select a small or large radius turn without having to upshift or downshift (and thus loose speed).  The differential lock prevented the tank from "self-steering" on uneven terrain, which meant that the driver didn't need to make periodic corrections when trying to drive in a straight line on a slant.  This system also prevents the loss of traction on one track when maneuvering in mud.  The only contemporary tanks with better steering were the Swiss Pz. 61/68.

 

The Leo 1 had a total of 383-407mm of total travel of its road wheels.  This was much better suspension than the M60 had, with a mere 292mm.  The AMX-30 was even worse with only 279mm of total travel, and Chieftain didn't even have independently suspended roadhweels, but even a single wheel could only translate through 242mm.  This gave the Leo 1 a considerable edge on other Western tanks on terrain with lots of small bumps, as it would much better isolate its crew from vibration and jolting.

 

The Leopard 1 had rubber-bushed, double-pin tracks.  These lasted longer than the single-pin tracks on Chieftain.  Leopard 1 also pioneered the powerpack concept.  I don't think any contemporary tank could have its entire engine and transmission swapped as quickly.  In Australian trials the Leo 1 was found to be more reliable than the M60, and while Chieftain and AMX-30 competed for last in that generation of tanks.

 

There were only two aspects of mobility where the Leopard 1 wasn't best in class at the time.  With a maximum hull width of 3.37 meters, it was somewhat outside the 3.15 Berne international railway gauge limit.  Leo 1s could still be transported by rail, but schedules would need to be double-checked to make sure that the train going in the opposite direction from the one carrying the tanks wasn't carrying anything really wide.  The AMX-30 and Pz. 61/68 were within the 3.15 meter limit, and thus enjoyed unrestricted rail movement.  Chieftain and M60 are both chunky, and stick out from their transport rail cars. The Leopard 1 also had about 10% greater mean maximum ground pressure than the M60A1, but had substantially lower MMP than the AMX-30 or Chieftain.  The M60 would have sunk into boggy ground and mud somewhat less than the Leo 1, but the Leo 1 would have sunk in substantially less than an AMX-30 or Chieftian.

 

So, aside from taking the silver medal in terms of rail transport and ground pressure, the Leo 1 was head and shoulders above contemporary Western MBTs for all aspects of mobility.

[Ramlaen]

https://www.welt.de/wirtschaft/article180519422/Schuetzenpanzer-Puma-Soldaten-duerfen-nicht-groesser-als-1-84-Meter-sein.html

 

According to this article when the development of the Puma started the height of future Germans was underestimated and it was not designed for dismounts over 184cm tall.

[Walter_Sobchak]

4 hours ago, Collimatrix said:

 

The Leo 1 beat the snot out of other Western MBTs in terms of practical mobility in its day.  There are some tests that show that Chieftains were almost as good, but it's trivial to set up a test where the primary limitation on average speed is avoidance of obstacles that are hard to see.  In that case, all drivers would need to slow down enormously so they could see the obstacles (hidden by tall grass, for instance), and all tanks tested would have the same practical mobility.

But on more representative courses, the Leopard 1 has several advantages over contemporary Western MBTs in addition to its higher power to weight ratio. 

 

The steering on the Leo 1 was better.  The Leo 1 had a two-speed steering drive and a differential lock.  This meant that the Leo 1 had two steering radii per transmission gear, which meant that the driver could select a small or large radius turn without having to upshift or downshift (and thus loose speed).  The differential lock prevented the tank from "self-steering" on uneven terrain, which meant that the driver didn't need to make periodic corrections when trying to drive in a straight line on a slant.  This system also prevents the loss of traction on one track when maneuvering in mud.  The only contemporary tanks with better steering were the Swiss Pz. 61/68.

 

The Leo 1 had a total of 383-407mm of total travel of its road wheels.  This was much better suspension than the M60 had, with a mere 292mm.  The AMX-30 was even worse with only 279mm of total travel, and Chieftain didn't even have independently suspended roadhweels, but even a single wheel could only translate through 242mm.  This gave the Leo 1 a considerable edge on other Western tanks on terrain with lots of small bumps, as it would much better isolate its crew from vibration and jolting.

 

The Leopard 1 had rubber-bushed, double-pin tracks.  These lasted longer than the single-pin tracks on Chieftain.  Leopard 1 also pioneered the powerpack concept.  I don't think any contemporary tank could have its entire engine and transmission swapped as quickly.  In Australian trials the Leo 1 was found to be more reliable than the M60, and while Chieftain and AMX-30 competed for last in that generation of tanks.

 

There were only two aspects of mobility where the Leopard 1 wasn't best in class at the time.  With a maximum hull width of 3.37 meters, it was somewhat outside the 3.15 Berne international railway gauge limit.  Leo 1s could still be transported by rail, but schedules would need to be double-checked to make sure that the train going in the opposite direction from the one carrying the tanks wasn't carrying anything really wide.  The AMX-30 and Pz. 61/68 were within the 3.15 meter limit, and thus enjoyed unrestricted rail movement.  Chieftain and M60 are both chunky, and stick out from their transport rail cars. The Leopard 1 also had about 10% greater mean maximum ground pressure than the M60A1, but had substantially lower MMP than the AMX-30 or Chieftain.  The M60 would have sunk into boggy ground and mud somewhat less than the Leo 1, but the Leo 1 would have sunk in substantially less than an AMX-30 or Chieftian.

 

So, aside from taking the silver medal in terms of rail transport and ground pressure, the Leo 1 was head and shoulders above contemporary Western MBTs for all aspects of mobility.

 

Because I am obligated by family pride and history, I have to defend the honor of the M60 by pointing out that it was effectively a much older design than the Leopard I.  Whereas the Leo 1 was part of the second generation of the postwar tanks, M60 is essentially an improved version of the US first generation postwar tank, the M48.  So to come in second in mobility while being older than its competitors (AMX-30, Chieftain, Leo I are all second gen tanks) is not bad at all.    Oddly, while M60 was considered a bit of a stopgag when it came out, it soldered on as the main US tank for over 20 years.  I also think it's interesting that the first generation of British postwar tanks, the Centurion, would go on to be one of the most successful tanks of the cold war, at least when upgraded with the M60 powertrain.  

[TokyoMorose]

1 hour ago, Walter_Sobchak said:

 

Because I am obligated by family pride and history, I have to defend the honor of the M60 by pointing out that it was effectively a much older design than the Leopard I.  Whereas the Leo 1 was part of the second generation of the postwar tanks, M60 is essentially an improved version of the US first generation postwar tank, the M48.  So to come in second in mobility while being older than its competitors (AMX-30, Chieftain, Leo I are all second gen tanks) is not bad at all.    Oddly, while M60 was considered a bit of a stopgag when it came out, it soldered on as the main US tank for over 20 years.  I also think it's interesting that the first generation of British postwar tanks, the Centurion, would go on to be one of the most successful tanks of the cold war, at least when upgraded with the M60 powertrain.  

 

To further muddle the waters, by the late 60s/early 70s, several drivetrain improvements and improved suspension components were developed for M60 that would have made up the performance gap had the army actually bought them. (Thinking of the XT-1400 and RK304 transmission options, various improvements to the engine culminating in the 1200hp versions, and the different torsion bar replacements)

[Bronezhilet]

8 hours ago, Collimatrix said:

 

The Leo 1 beat the snot out of other Western MBTs in terms of practical mobility in its day.  There are some tests that show that Chieftains were almost as good, but it's trivial to set up a test where the primary limitation on average speed is avoidance of obstacles that are hard to see.  In that case, all drivers would need to slow down enormously so they could see the obstacles (hidden by tall grass, for instance), and all tanks tested would have the same practical mobility.

But on more representative courses, the Leopard 1 has several advantages over contemporary Western MBTs in addition to its higher power to weight ratio. 

 

The steering on the Leo 1 was better.  The Leo 1 had a two-speed steering drive and a differential lock.  This meant that the Leo 1 had two steering radii per transmission gear, which meant that the driver could select a small or large radius turn without having to upshift or downshift (and thus loose speed).  The differential lock prevented the tank from "self-steering" on uneven terrain, which meant that the driver didn't need to make periodic corrections when trying to drive in a straight line on a slant.  This system also prevents the loss of traction on one track when maneuvering in mud.  The only contemporary tanks with better steering were the Swiss Pz. 61/68.

 

The Leo 1 had a total of 383-407mm of total travel of its road wheels.  This was much better suspension than the M60 had, with a mere 292mm.  The AMX-30 was even worse with only 279mm of total travel, and Chieftain didn't even have independently suspended roadhweels, but even a single wheel could only translate through 242mm.  This gave the Leo 1 a considerable edge on other Western tanks on terrain with lots of small bumps, as it would much better isolate its crew from vibration and jolting.

 

The Leopard 1 had rubber-bushed, double-pin tracks.  These lasted longer than the single-pin tracks on Chieftain.  Leopard 1 also pioneered the powerpack concept.  I don't think any contemporary tank could have its entire engine and transmission swapped as quickly.  In Australian trials the Leo 1 was found to be more reliable than the M60, and while Chieftain and AMX-30 competed for last in that generation of tanks.

 

There were only two aspects of mobility where the Leopard 1 wasn't best in class at the time.  With a maximum hull width of 3.37 meters, it was somewhat outside the 3.15 Berne international railway gauge limit.  Leo 1s could still be transported by rail, but schedules would need to be double-checked to make sure that the train going in the opposite direction from the one carrying the tanks wasn't carrying anything really wide.  The AMX-30 and Pz. 61/68 were within the 3.15 meter limit, and thus enjoyed unrestricted rail movement.  Chieftain and M60 are both chunky, and stick out from their transport rail cars. The Leopard 1 also had about 10% greater mean maximum ground pressure than the M60A1, but had substantially lower MMP than the AMX-30 or Chieftain.  The M60 would have sunk into boggy ground and mud somewhat less than the Leo 1, but the Leo 1 would have sunk in substantially less than an AMX-30 or Chieftian.

 

So, aside from taking the silver medal in terms of rail transport and ground pressure, the Leo 1 was head and shoulders above contemporary Western MBTs for all aspects of mobility.

Plus the Leo didn't poison everybody in its vicinity with unburnt fuel, which the Chirftain kinda did.