# Panther tank keeps original weight



## wiking85 (Nov 8, 2013)

What if the Panther tank kept its original design weight of 35 tons, keeping the 75mm L70 gun, but having less armor. Would it have been more mechanically reliable and good to go in early 1943, instead of mechanically deficient and basically unusable by July 1943? Could Kursk have been launched sooner if the Panther was ready by May 1943?

https://en.wikipedia.org/wiki/Panther_tank


> The MAN design embodied more conventional German thinking with the transmission and drive sprocket in the front and a centrally mounted turret. It had a gasoline engine and eight torsion-bar suspension axles per side. Because of the torsion bar suspension and the drive shaft running under the turret basket, the MAN Panther was higher and had a wider hull than the DB design. The Tiger I Henschel design concepts of large, overlapping, interleaved road wheels with a "slack-track" using no return rollers for the upper run of track were repeated with the MAN design for the Panther. These large steel wheels added to the protection of the hull from a lateral penetrating shot.
> 
> The two designs were reviewed over a period from January through March 1942. Reichminister Todt, and later, his replacement Albert Speer, both recommended the DB design to Hitler because of its several advantages over the initial MAN design. However, at the final submission, MAN improved their design, having learned from the DB proposal, and a review by a special commission appointed by Hitler in May 1942 ended up selecting the MAN design. Hitler approved this decision after reviewing it overnight. One of the principal reasons given for this decision was that the MAN design used an existing turret designed by Rheinmetall-Borsig, while the DB design would have required a brand new turret to be designed and produced, substantially delaying the commencement of production.[7]
> 
> ...


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## davebender (Nov 9, 2013)

15 tons. Original Panzer III specification weight.
18 tons. Original Panzer IV specification weight.

30 tons. 1937 specification weight for German heavy tank.
36 tons. 1938 specification weight for German heavy tank.
.....55 ton Tiger I was vehicle placed into production during fall 1942.

30 to 35 tons. Original specification weight for Panther tank.

There's a pattern here. Every German tank larger then Panzer II ended up weighing about 50% more then specification weight. Germany had competent engineers so the reasons must be political.


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## Shortround6 (Nov 9, 2013)

Something seems a bit off with that quote. The 75 ton Tiger went into service about year after the 45-48 ton Panther, so the Panther could hardly be "developed" in response to the Heavy Tiger II (King, Royal, whatever) tank. 

AS for making a 30-35 ton tank with the 75mm L70 gun "German Style" ? 

Only if the armor has the resistance of pie crust. The gun is a big one and needs a large turret (and turret ring) if the gun is to have full elevation and depression ( and be loaded at the elevation limits). The Germans used front drive sprockets and required the drive shaft to run on top of the torsion bars requiring extra height in the hull. 

Steel weighs 40lbs per sq ft 1inch thick. So taking a piece 8 feet wide and 6 feet high and and 20mm thick ( roughly 80% of an inch) is about 1540lbs. Roughly the the difference between a 60mm and 80mm glacis plate on the Panther ?? Better dimensions welcome. 

Pulling 10 tons of armor OUT of the Panther requires either very thin armor OR a _much _ smaller tank to begin with.

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## Shortround6 (Nov 9, 2013)

davebender said:


> 15 tons. Original Panzer III specification weight.
> 18 tons. Original Panzer IV specification weight.
> 
> 30 tons. 1937 specification weight for German heavy tank.
> ...



Hardly. Don't blame politics for engineering realities. 

In some cases the original specification weight limit corresponded with a certain class of bridging equipment. Trouble was you couldn't make a workable tank within the weight limits ( or at least a very good one.) 

The MK II was a pretty poor tank, even for it's time. It's just that much of it's opposition was even worse in other ways. 

If you want a 5 man crew the tank needs a certain volume which dictates a certain weight _IF_ the makers keep the specified armor thickness. 

SO you have a choice, build a tank that works in combat ( and 15-30mm armor on the early MK IIIs and MK IVs _just worked[/I) and is over weight or build a tank that meets the weight limit and can barely keep out rifle bullets. If that is what you call "politics" ?_


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## Mobius (Nov 9, 2013)

davebender said:


> There's a pattern here. Every German tank larger then Panzer II ended up weighing about 50% more then specification weight. Germany had competent engineers so the reasons must be political.


Might be current events. There might be a war going on and need trumped theory.


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## dobbie (Nov 9, 2013)

The Panther might have been able to maintain its original design weight, but something would have to give. Smaller/lighter drivetrain. Lighter armor could in addition have been a way to go with greater angularity so an anti tank projectile still has "more armor" to penetrate due to the increased angle.


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## davebender (Nov 9, 2013)

I agree if "current events" includes the massive naval Z plan approved during January 1939. You can build a lot of tanks with the steel historically allocated to construction of German dreadnoughts and heavy cruisers.

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## Shortround6 (Nov 9, 2013)

While the Naval Z plan is a pet bugaboo of yours the size and number of ships have got nothing to do with wither a tank design meets the original specification weight or not.


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## Juha (Nov 9, 2013)

IIRC the original Panther was designed with 60mm frontal armour and with 75mm L/60 gun. Both would have been enough for 1943 - early 44 at least.


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## tomo pauk (Nov 10, 2013)

A tank with 'all rear' powerpack/powertrain layout should save both on length and height, and that means less weight with same protection. The examples of 'compact tank - big gun - decent armor' being T-34-85, T-44 and M-26. Or, eventually, for 'all front' layout, Merkava-style, also present in some li
Going for 'all rear' or 'all front' layouts would dictate giving up on current German design practice, however.

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## davebender (Nov 10, 2013)

> Going for 'all rear' or 'all front' layouts would dictate giving up on current German design practice


Moving turret forward would be a problem for WWII era German tanks as most had a relatively long main gun. However putting engine and transmission in front might work.


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## wiking85 (Nov 10, 2013)

VK 30.02 (M) - World Of Tanks


> Armor
> Hull Armor	60/40/40 mm
> Turret Armor	80/45/45 mm



VK 30.02 Panther Prototype

Apparently they build the 35 ton prototype, here are some images:


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## tomo pauk (Nov 10, 2013)

davebender said:


> Moving turret forward would be a problem for WWII era German tanks as most had a relatively long main gun. However putting engine and transmission in front might work.



The tanks I've listed have also featured long barrels at front, there was not much of sticking the muzzle in the ground incidents associated with them. Not even with SU-85 or SU-100, with barrels/muzzles protruding even more at front.



wiking85 said:


> VK 30.02 (M) - World Of Tanks
> 
> 
> VK 30.02 Panther Prototype
> ...



Where can one read that prototype weighted 35 tons?


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## wiking85 (Nov 10, 2013)

tomo pauk said:


> The tanks I've listed have also featured long barrels at front, there was not much of sticking the muzzle in the ground incidents associated with them. Not even with SU-85 or SU-100, with barrels/muzzles protruding even more at front.
> 
> 
> 
> Where can one read that prototype weighted 35 tons?


Wikipedia with the quote I gave in the OP?

https://de.wikipedia.org/wiki/Panzerkampfwagen_V_Panther


> After the tender two prototypes have been developed, the VK.30.01 Daimler-Benz (DB) and the VK.30.02 MAN (MAN) . The proposal of the Daimler-Benz as they strongly resembled the T-34, while the MAN design was a new independent structure for German experiences and requirements. A special commission for the selection of manufacturing model suggested the design of MAN on the following grounds:
> The Tower of Daimler-Benz was incomplete and not ready for production before December 1942, and the turret ring diameter 5 cm narrower than the Rheinmetall MAN tower for the model so that the DB Panther without tower was available.
> The drive of the MAN Panther was the better weapons platform.
> The engine room of the insular MAN Panthers allowed underwater driving without tedious preparations.
> ...


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## Denniss (Nov 11, 2013)

Moving turret forward was a no-go unless you move the track drive to the rear. You need some space for a driver there, also too much weight on the forward suspension.
BTW there must be a reason why even modern tanks have the turret in a center location.


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## tomo pauk (Nov 11, 2013)

> Moving turret forward was a no-go unless you move the track drive to the rear. You need some space for a driver there, also too much weight on the forward suspension.



Well put.



> BTW there must be a reason why even modern tanks have the turret in a center location.



If we consider the turret overhangs too, then yes, turret is at center. The turret ring, however, is not at a central location. 





http://data.primeportal.net/m1_iraqp/rob_m1_broken/Iraq_046.jpg

The Leo 2, Challenger and M1 are transported with barrels pointed backwards, in order to cut the overall length.

http://upload.wikimedia.org/wikipedia/commons/b/ba/M1_Abrams_loaded_on_a_C-5_Galaxy.jpg

http://images.fineartamerica.com/images-medium-large/a-tank-transporter-hauling-a-challenger-andrew-chittock.jpg



wiking85 said:


> [Where can one read that prototype weighted 35 tons?]
> Wikipedia with the quote I gave in the OP?
> 
> https://de.wikipedia.org/wiki/Panzerkampfwagen_V_Panther



Well, if you point me to the single sentence where it says that Panther's prototype weighted 35 tons, I'm buying a beer


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## davebender (Nov 11, 2013)

Modern tanks weighing over 40 tons don't need to worry as much about long cannon placing too much weight on forward suspension but it was a serious issue for small tanks such as Panzer III and Panzer IV. I suspect it wouldn't be a problem for Panther lite weighing 35 to 40 tons but it's understandable German tank designers would be cautious as they had no experience with tanks that large.

Easy solution.
Early model Panther lite which should begin production during 1942 get the same cannon and Krupp built turret which historically armed Panzer IVG. Then experiment with a new turret and 7.5cm/70 cannon. Even if the new turret / cannon combination doesn't work you still have an excellent WWII era tank, far superior to Panzer IVG.


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## Shortround6 (Nov 11, 2013)

The _idea_ of a Panther _lite_ is a fabrication with little basis in reality. 

In order to loose 10 long tons of weight (roughly 10 metric tons) you need to loose 560 sq ft of armor 25.4mm (one inch) thick. Now do you even _HAVE_ 560 sq ft of armor on a Panther? The belly plate is about 99 sq ft. each side is about 85 sq feet or about 270 sq ft for the bottom and sides. Front, Back, top deck and Turret?????

Since one source gives the top deck armor as 15mm you can't cut anything there, floor armor is 20+13mm?? 20 in the front ant 13 in the rear or 33 total? either cut nothing or have 8mm belly armor. sides of hull and rear are 40mm thick, cut to 15mm????
Cut 45mm turret sides to 20mm thick? 

I hope you get the idea. Hitler may get the blame for a lot of things and rightly so but this looks like somebody ( or group of some somebodies) is trying to shift the blame. There is no way on this Earth that adding 20mm of armor to the Front alone of the Panther tank added any more than 2700-2800lbs to the tank if that much. 20mm of armor is about 32lbs per square foot. 

You either design for the 7.5cm/70 cannon or you don't. it is not a drop in replacement for the smaller gun. You need a bigger turret ring for one thing.


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## tomo pauk (Nov 11, 2013)

Fine post. People tend to forget that Panther was a big tank, being long, wide and high (higher?) as KV-85. It was not offering a thicker armor. 

BTW, an even easier solution, Dave - build the JgdPz-IV/70


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## Juha (Nov 11, 2013)

As I wrote earlier, IIRC the new gun was initially L/60 but because of its penetration power was a little lower than what was wanted it was modified to L/70 gun, so a bit longer and heavier barrel and probably some mods also to the rear end to rebalance the gun.


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## davebender (Nov 11, 2013)

http://www.tank-net.com/forums/index.php?showtopic=36959
Al a meeting on 15 September 1939, Wa Pruef 6 and Krupp discussed the design of a new chassis, the VK 20.01 (IV), as a further development of the Pz.Kpfw.IV series. The engine compartment and the Maybach HL 116 engine were to be adopted from the VK 20.01 (III). Maximum speed was to be 42 kilometers per hour, the same as the Pz.Kpfw.IV Ausf.C. The suspension was selected to support a vehicle weight of 20 metric tons with a hull width of 1820 mm and an overall width of 2900 to 2950 mm. The Schachtellaufwerk (interleaved roadwheel suspension) from the VK 20.01 (III) couldn't be used, since it resulted in an overall width of about 3040 mm and exceeded the weight specification. Krupp proposed a six- wheel suspension with leaf springs which could use components from the normal eight-roadwheel suspension for the Pz.Kpfw.IV.

At a meeting on 28 October 1939 with Wa Pruef 6, a diameter of 630 mm was set for a six-roadwheel suspension for the VK 20.01 (IV). New Kgs 61/400/120 tracks were to be utilized. The designation for VK 20.01 (IV) evolved to VK 20.01 (BW) in November and then was changed to B.W.40 in December 1939.

On 13 December 1939, the frontal armor for the B.W.40 was increased from 30 mm to 50 mm thick. The basic hull shape for the B.W.40 was the same as the Pz.Kpfw .IV Ausf.D. On 4 January 1940, Wa Pruef 6 notified Krupp that two armor hulls and one soft steel hull were to be produced for the three B.W.40 experimental chassis. Three superstructures and rear decks were to be made from soft steel.

On 16 May 1940, Wa Pruef 6 informed Krupp that in consideration of the wartime situation, the B.W.40 project was to be shelved.
Also in May 1940, Krupp initiated a new design in coordination with Wa Pruef 6, the VK 20.01 (K) with either the Maybach HL 116 or HL 115 motors. As recorded in Krupp's 1939/1940 fiscal year report, preliminary proposals had been completed for the VK 20.01 (K) with 5 cm armament and heavier armor. A full-scale wooden model was being completed, and a detailed design had been started. The experimental turret for the VK 20.01 was being designed by Krupp with 5 cm Kw.K. L/42 armament. Frontal armor was to be 50 mm thick, side and rear armor 30 mm thick.

By 24 October 1940, Krupp had received contracts for three VK 20.01 (K) developmental chassis and by 12 November 1940 a contract for production of a 0-Serie of 12 VK 20.01 (K) complete with 5 cm gun turrets. Wa Pruef 6 had awarded contracts to M.A.N, and Daimler-Benz for the design of new tanks with 7.5 cm gun turrets in the 20 ton class.

In March 1941, Krupp proposed to complete three developmental VK 23.01 (K) chassis and six experimental VK 23.01 (K) with torsion bars. The VK 23.01 (K) was to have the power train components designed by Kniepkamp and developed by M.A.N.

On 18 April 1941, Wa Pruef 6 informed Krupp that they were to concentrate on development of a new submersible turret with a 5 cm Kw.K. L/60 gun for the VK 20.01 (K). The experimental turret for the new VK 20.01 (K) was to be completed by 1 February 1942 directly followed by production of 12 turrets for the 0-Serie.

By July 1941, an additional contract had been awarded to Krupp for three developmental VK 23.01 (K) chassis in soft steel without turrets. The previous contract for a 0-Serie of 12 was revised to specify two redesigned variants: six VK 20.02 (K) and six VK 23.01 (K). The six armored VK 20.02 (K) were to have 5 cm Kw.K. L/60 guns in their turrets.

Both the VK 20.01 (K) and VK 20.02 (K), designed for a maximum speed of 56 km/hr, had the same leaf spring suspension with six roadwheels (700 mm diameter) running on 450 mm wide Kgs 62/450/120 track. The total weight of a complete VK 20.01 (K) including a turret was calculated to be 21.5 metric tons, compared to the VK 20.02 (K) at 23 metric tons.

To meet the requirement for standardization demanded by Kniepkamp, the VK 23.01 (K) was to have a Schachtellaufwerk designed by M.A.N, with six 880 mm diameter roadwheels, a torsion bar suspension, and 474 mm wide Kgs 63/474/110 tracks. The first VK 23.01 (K) developmental chassis with torsion bar suspension, outfitted for total submersion, etc., could be delivered, at the earliest, about 1 October 1942.

In designing their VK 23.01 (K), Krupp contacted Zahnradfabrik Friedrichshafen and Maybach on 19 September 1941 in order to obtain the latest installation drawings of transmissions for the Dreiradien-Lenkgetriebe (triple radius steering gear) designed by M.A.N.

In a report written in January 1942, Woelfert related how the design and completion of the VK 20.02 (K) had frequently been delayed due to the following reasons: Initially a 5 cm turret was specified with an inner turret ring diameter of 1350 mm without a traversing floor. Then, on 10 October 1941, a 5 cm turret with an inner turret ring diameter of 1400 mm was required, to allow the option of mounting a 7.5 cm gun turret. Finally, the 7.5 cm Einheitsturm (standard turret) with 7.5 cm Kw.K.44 was specified, at first with an inner turret ring diameter of 1560 mm, later increased to 1600. As a result of continuously increasing the turret ring diameter, the hull width was expanded from 1600 to 1650 mm and the hull (originally 400 mm shorter) had to be repeatedly lengthened. Also, the ammunition storage was fundamentally changed. Along with this came the requirement to slope the superstructure walls, especially the driver's front plate.

In a meeting on 17 December 1941 with Krupp, Oberst Fichtner (head of Wa Pruef 6) expressed his position on tank development as follows: Against the advice of Wa Pruef 6, higher authority had decided that the weight class for the future tank should be 30 tons and not the 24 ton tank proposed by Wa Pruef 6. Fichtner was opposed to this decision. In his opinion, time would be lost since the *30 ton tank had yet to be developed, whereas development of the 24 ton tank was almost completed.*


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## GrauGeist (Nov 11, 2013)

But the Panther was VK30.02 implimented by Guderian's Panzerkommision results of fall 1941 after examining captured T-34 tanks on the eastern front. As it happens, the VK30.02 was to be 30 - 35 tons at the onset of the design.


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## Shortround6 (Nov 11, 2013)

Sorry, it doesn't pass the "smell" test. 

Somehow, despite being made longer, wider, mounting bigger turrets, using wider tracks, bigger road wheels, etc this thing not only didn't gain weight it actually went _down?_.

Keeping the same engine and yet gaining 14kph in speed seems like a good trick too, a 33% increase in speed using the same engine? 

Lots of contracts placed, were are the results? Like even a few photographs of test chassis or even mock ups? 

BTW extending the hull 400mm for a hull 4 ft tall requires about 500lbs for 30mm side armor, not counting top and bottom armor. Top and bottom armor if 15mm thick is another 375lbs or so. I really do like they can drop a 75mm KwK L70 gun into a chassis originally designed for a 50mm/L42 gun with just a _little_ stretching. The Panther gun weighing just about double what the 7.5cm L48 gun in the MK IV (roughly 1/2 a ton more) did let alone the 5cm L42 gun. (closer to 4 times the weight) and it is not just the weight but the bulk of the gun. ALL the weight is not the result of a longer barrel but a bigger breech area, a bigger breech block and larger recoil cylinders, which have to housed in a bigger turret (assuming, of course that the same amount of room to work the gun is desired and circus contortionists are not used for loaders).


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## silence (Nov 11, 2013)

tomo pauk said:


> Fine post. People tend to forget that Panther was a big tank, being long, wide and high (higher?) as KV-85. It was not offering a thicker armor.
> 
> BTW, an even easier solution, Dave - build the JgdPz-IV/70



As I recall, dimensionally it was bigger than a Tiger I: longer and taller, but maybe a bit narrower. It always seemed strange to me that it would be so. There must be a lot of wasted volume.


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## GrauGeist (Nov 11, 2013)

For one thing, it had to be taller because of it's drive train suspension design. If it had better side armor, that might not have been such a critical issue.


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## tomo pauk (Nov 12, 2013)

While the suspension really influenced the height, it was the layout of transmission than pushed up both height and, possibly, the length.

Panther's cutaway

The T-44-85 with Panther, note the hull and overall heights:

http://upload.wikimedia.org/wikipedia/commons/e/e9/T-44-85_and_Pather.jpg

T-44-122 (!!) with Panther. The Soviets were always capable to find the way for huge cannons to be installed in modestly sized tanks.

http://commons.wikimedia.org/wiki/File:T-44-122_and_Panther.JPG


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## wiking85 (Nov 12, 2013)

Prototype:






Production model:


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## Shortround6 (Nov 12, 2013)

tomo pauk said:


> T-44-122 (!!) with Panther. The Soviets were always capable to find the way for huge cannons to be installed in modestly sized tanks.]



It was often done by limiting elevation and depression of the main gun. Elevation affects max range ( not important unless you are using tanks for artillery) and teh ability to shoot onto hill sides/upper floors of buildings. Depression affects the ability to fire into valleys and More importantly, the ability to use hull down positions. Being able to shoot while exposing only the turret may be a big advantage compared to exposing the upper half of the hull. 

For Stugs and tank destroyers with fixed guns, fitting larger guns sometimes means a bit less traverse in addition to less elevation and depression. Large gun Soviet tanks were also rather notorious for limited ammo supply. 

The trade-offs were known and accepted by the Soviets, wither the Germans would accept the same trade-offs?

A T-34/85 carried 55 rounds of main gun ammo (?). A Panther carried 79 ( or more) of larger/bulkier rounds. A Panther _lite_ might carry 1/2 the ammo of the big Panther. This means you need more tanks to get the same combat effect. Many tanks carried more HE than AP ammo and could run out of one type or the other in a matter of minutes in a hot action, requiring the tanks (AFV) to pull out of action for resupply. Gone from the battlefield when needed is almost as good as knocked out.


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## tomo pauk (Nov 12, 2013)

The T-44-122 was too much of a cannon for too small tank even for the Soviets, I guess. They continued with such a big cannon only for heavy tank line, ending with the T-10. The T-44 was trialed also with 100 mm, certainly a better match. The ammo count for the T-44-122 was probably even smaller than 28 rounds carried by IS-2.



> A T-34/85 carried 55 rounds of main gun ammo (?).A Panther carried 79 ( or more) of larger/bulkier rounds.



Onwar.com states 56-60 for the T-34-85. The Panther was a bigger tank, the similarly sized KV-85 carried 71 round, per onwar.com. Curiously enough, the same source states for the IS-1 carrying only 59 rounds for the 85mm.



> A Panther lite might carry 1/2 the ammo of the big Panther. This means you need more tanks to get the same combat effect. Many tanks carried more HE than AP ammo and could run out of one type or the other in a matter of minutes in a hot action, requiring the tanks (AFV) to pull out of action for resupply. Gone from the battlefield when needed is almost as good as knocked out.



The need to carry more HE than AP also points out that a 75mm L/70 was a worse choice for a 45-ton tank than 88mm? The size of ammo was about the same, yet the 88mm HE shell was 50% heavier; the AP performance of both was well suited for needs of Eastern front warfare.
A _Panther lite_ with 40 rounds of 75mm? More of lower value tanks means more engines, cannons, sights, radios, crews... Indeed it does not sound like a good investment of limited resources.

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## Shortround6 (Nov 12, 2013)

From Tony Williams website.

The 75mm L/70 ammo was actually a bit fatter than the 88mm L/56 ammo. 

Photo also points out the near absurdity of re-gunning a tank designed to use 50mm L/42 (50 X 289R) ammo for 75mm L/70 ( 75 X 640R) ammo.

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## silence (Nov 12, 2013)

tomo pauk said:


> The Soviets were always capable to find the way for huge cannons to be installed in modestly sized tanks.



IIRC, they took size limiting to such an extreme that the T-54/54 had crew height limits of something like 5'6".


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## parsifal (Nov 12, 2013)

I am very doubtful it would be possible to mount the L70, and also provide it with reasonable mobility and protection in a turreted AFV. 

By comparison the Stug III mounted the L-48 in an SPG configuration, with a lot less protection, but still weighed 25 tons. Not that i thik that to be a problem. i think the Stug was a far better investment prospect for the Germans than the over lavish Panther or worse the profligate tiger designs. They could have had at least twice as many Stugs as Panthers to fight their defensive battles 1943-5.

I am not aware of any design attempt for a turretted version of the Stug III...essentially a Mk III with a turretted L48. The problem was the turret ring...it was simply too small, but Im not convinced this was not possible. A simplified design, devoid of all the frills and froth and were the hallmark of all the other designs. Basic, cheap, easy to produce, based on a proven design. The MkIV almost fitted that bill, but needed simplification as well. Thats what they needed (ie a simple, basic, easy to produce, reliable tank that could be mass produced cheaply and quickly).


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## Denniss (Nov 12, 2013)

You would need to redesign the upper superstructure for a larger ring, as the Panzer III is 40 cm shorter than the IV you'd have to move the turret a bit forward which, together with the long and heavy gun, would lead to an enourmous weight shift to the forward suspension. This would require further work to balance this out, in short: not worth the hassly if you already have the Pz IV capable of holding the gun.
StuG III was 24 tonnes.


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## parsifal (Nov 12, 2013)

so would it be possible to simply lengthen and widen the hull. Make it bigger to accomodate the bigger turret ring?


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## Denniss (Nov 13, 2013)

"Simply" lengthen and widen the hull = throw away all the machinery tools for hull production and build them anew = high cost and major drops in production. Useless investment because you had the long-gunned Pz IV and could use most of the tool for StuG III with long gun, the latter for far less investments.


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## silence (Nov 13, 2013)

parsifal said:


> I am very doubtful it would be possible to mount the L70, and also provide it with reasonable mobility and protection in a turreted AFV.
> 
> By comparison the Stug III mounted the L-48 in an SPG configuration, with a lot less protection, but still weighed 25 tons. Not that i thik that to be a problem. i think the Stug was a far better investment prospect for the Germans than the over lavish Panther or worse the profligate tiger designs. They could have had at least twice as many Stugs as Panthers to fight their defensive battles 1943-5.



As much as I like the Panther I gotta agree, although I'd switch over to the JPz IV/70 and develop the Jagdpanther as soon as possible. Naturally this means they're going to have to be introduced much earlier than historically: they're gonna be needed for the IS-IIs and the heavier Soviet TDs like the (I)SU-152 series. The StuGs are fine for the West unless the Pershing and Centurion get introduced, and the East until the end of '43.


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## Shortround6 (Nov 13, 2013)

The trouble is that these limited traverse tank destroyers are NOT tanks and while they can substitute to some extent the Germans still needed _real_ tanks even for limited offensives (local counter attacks) even if the general tone of combat was defensive. 

Please note that the tank destroyers/tank hunters had a some what limited anti-personnel ability. While they could and did carry HE ammo they were limited (mostly) to a single machine gun with around 600 rounds for most of them. 
Tiger I and Panthers carried (if full?) 4800-5100 rounds of machine gun ammo and one gun aimed with the main gun sight. A tank platoon can supply a rather formidable amount of fire support for an infantry unit that a TD platoon cannot. 

Now perhaps they could have cut the ammo to 2500-3000 rounds and cut the main gun ammo a bit and wound up with a smaller volume of space that had to be armored ( assistant driver/hull gunner is generally figured to consume 35 cubic feet) but getting rid of ALL the tanks with rotating guns turrets might not have been smart.

Something to consider on the effectiveness of a tank is it's _rate of engagement_, how many targets can it engage in a given period of time. This includes rate/s of fire (practical, ie getting spare ammo from some were besides a ready rack), turret or vehicle traverse, how easy or quickly the gun can be swung from one target to another and how much situational awareness the commander can keep and thus keep directing the gunner onto new targets while having the driver maneuver the vehicle (either to bring gun onto target or gain new firing position or avoid a threat).
Obviously training and experience play a big part but cramped fighting compartments with limited outward visibility and slow traverse ( or limited traverse) also play a part.


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## wiking85 (Jun 28, 2014)

parsifal said:


> I am very doubtful it would be possible to mount the L70, and also provide it with reasonable mobility and protection in a turreted AFV.



Apparently the 35 ton version was built, it just had less armor than the historical final production version of the Panther, 60mm instead of 80mm for the hull. The extra weight from the armor required heavier running gear, which when coupled upped the weight to 44 tons from the 35 tons of the prototype. 












Guerra abierta: Daimler Benz VK3002


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## Shortround6 (Jun 29, 2014)

That is the common excuse but it doesn't stand up very well. 

Steel weighs 40lbs per square ft for a 1 in thickness. As a rough measure 20mm is 80% of 1in (25.4mm) or 32lbs per square ft. A chunk of armor 6.435 ft wide (distance between the tracks) and 10 ft high (roughly figuring 5 feet from hull floor to hull roof, I can't read the numbers in drawing and doubling the height for a 60 degree angle (not 55) gives a weight of armor of 2059lbs. Doesn't count the wings/triangles over the tracks counts the lower front plate. 

A little over 1 ton of armor caused an increase of 9 tons in the running gear?????

Somebody wants to do a more accurate number on the frontal armor area be my guest.


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## wiking85 (Jun 30, 2014)

Shortround6 said:


> That is the common excuse but it doesn't stand up very well.
> 
> Steel weighs 40lbs per square ft for a 1 in thickness. As a rough measure 20mm is 80% of 1in (25.4mm) or 32lbs per square ft. A chunk of armor 6.435 ft wide (distance between the tracks) and 10 ft high (roughly figuring 5 feet from hull floor to hull roof, I can't read the numbers in drawing and doubling the height for a 60 degree angle (not 55) gives a weight of armor of 2059lbs. Doesn't count the wings/triangles over the tracks counts the lower front plate.
> 
> ...



Entirely new mechanics and IIRC a new more powerful engine, while also having to upgrade the front suspension due to the weight increase and imbalance at the front caused by twice as much armor to the front as the rear. There might have been something to balance the weight toward the back. It wasn't just a simple armor adjustment.


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## Shortround6 (Jun 30, 2014)

wiking85 said:


> Entirely new mechanics and IIRC a new more powerful engine, while also having to upgrade the front suspension due to the weight increase and imbalance at the front caused by twice as much armor to the front as the rear. There might have been something to balance the weight toward the back. It wasn't just a simple armor adjustment.



What you say may very well be true but the excuse of the extra armor doesn't hold up and the people who propose "what if" the Panther had kept a 60mm front plate are whistling in the dark. 

What engine was proposed or planned for the 60mm armor version? The First 250 Tiger tanks got an aluminium block HL 210 engine instead of the iron block HL 230 but the HL 230 is basically a bored out HL 210, weight difference is? 

SOme people want to blame Hitler (or somebody) for the 10 ton weight increase instead of accepting the fact the Panther was never going to be a 35/36 ton tank given it's size unless a _lot_ of the armor was reduced in thickness. 
No other _production_ tank engine came close to giving the needed power. 
New "mechanics" means??? New transmission and steering gear? Was going to be needed anyway and not due to a 1 ton increase in armor weight. 
Armor was already 50% thicker on the front than on the back and due to slope the front armor was well over 50% heavier to begin with.


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## wiking85 (Jun 30, 2014)

It would seem the frontal area was larger than the rear due to the layout, which increased the weight to the front more.
Plus the under/over of the hull was thicker than advertised with 85mm for the over and 65mm for the under part, both more than the original spec. The front half of the bottom armor was doubled to 30mm from 16mm The original engine was supposed to be the HL210, but the increase from aluminum to steel would up the weight. Don't know that the weight difference was though:
https://en.wikipedia.org/wiki/Maybach_HL210


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## wiking85 (Jun 30, 2014)

Shortround6 said:


> That is the common excuse but it doesn't stand up very well.
> 
> Steel weighs 40lbs per square ft for a 1 in thickness. As a rough measure 20mm is 80% of 1in (25.4mm) or 32lbs per square ft. A chunk of armor 6.435 ft wide (distance between the tracks) and 10 ft high (roughly figuring 5 feet from hull floor to hull roof, I can't read the numbers in drawing and doubling the height for a 60 degree angle (not 55) gives a weight of armor of 2059lbs. Doesn't count the wings/triangles over the tracks counts the lower front plate.


They didn't use just steel, but rather a heavier alloy with nickel, tungsten, molybdenum, and manganese.
https://en.wikipedia.org/wiki/Panther_tank#Armor


> As the war progressed, Germany was forced to reduce or no longer use certain critical alloy materials in the production of armor plate, such as nickel, tungsten, molybdenum, and manganese; this resulted in lower impact resistance levels compared to earlier armor.[53] Manganese from mines in the Ukraine became unavailable when the German Army lost control of this territory in February 1944. Allied bombers struck the Knabe mine in Norway and stopped a key source of molybdenum; other supplies from Finland and Japan were also cut off. The loss of molybdenum, and its replacement with other substitutes to maintain hardness, as well as a general loss of quality control resulted in an increased brittleness in German armor plate, which developed a tendency to fracture when struck with a shell. Testing by U.S. Army officers in August 1944 in Isigny, France showed catastrophic cracking of the armor plate on two out of three Panthers examined.[54][55]


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## Shortround6 (Jun 30, 2014)

And the difference in weight per cubic foot or per cubic in is what???

US Navy specified some armor thicknesses in by weight. As in 20lb bulkheads (1/2in) or decks or gun tubbs, etc. 15lb plate was 3/8 in. Adding a few percent of nickel or other alloying agents is only going to change the weight a few percent. 

I have worked on the frontal area a bit more and the hull was 1850mm wide between the tracks and 1330mm high from hull floor to roof top. Doubling that for a 60 degree angle ( I can't be bothered to figure how much less it is for 55 degrees) gives 2660mm or 8.73ft. Times 6.07 ft for the width gives about 53 square ft. the "wings" over the track when added together ( and assuming a 45 degree side angle to make things easy) make a plane 1060mm wide and 430mm high (doubled to 860mm due to 60 degree angle) for another 9.8 sq ft. 62.8 square ft times 32lbs is 2009lbs. Please note that this counts the lower plate as 80mm thick and not it's actual 60-65mm and plates at 55 degrees will be a bit shorter than plates angled at 60 degrees. So this is sort of worst case. but changing the lower front plate from 60mm to 65mm gains what? 8lbs per square foot? 

Maybe the turret gained a bit of weight too but obviously even changing things by 300-500lbs doesn't come close to the 10 ton gain in weight (just how much heavier do you need to make torsion bars to handle the extra load? or how much heavier are the road wheels? 

While the iron HL 230 weighs more than the Aluminium HL210 the Aluminium one had some problems and in any case the heavier engine in the back should help balance the extra armor in the front. 

but changing the lower front plate from 60mm to 65mm gains what? 8lbs per square foot?


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## razor1uk (Jun 30, 2014)

Informative and stirring thread so far, without it going in circles yet either  , wasn't the most of the early panther running gear - steering transmission and reduction drive gearboxes from the PzkfwIV? which mere mostly 'subservient country' slave made - hence some early reliability problems with them trying to drive a tank that was near enough double their original design weight limit from the IV - and those IV reduction drive gearbox units were based upon the III's?!?

I think if the Germans had made the track treads a bit wider between links (not as much russian wide in length per link), they would still have had a smooth ride without so many pins, bushes, links and locking grubs screws, saving much weight, and stresses from the running gear loadings and unsprung weight while increasing power to weight ratios, possible improving the ground area to weight figures even if the links were a bit longer giving slightly less ground area per track, or been used to make the links wider for improved lower ground pressure mobilty at similar weigtages?

Looking at the tanks of that era, the Germans had the most links per track than any other country, which when coupled with adequately matched torsion bar susp'n gave a smoother ride and additional track to surface obstacle grip/mobility, at the cost of extremely heavy tracks - which depending on running speeds. could aid or hinder the susp'n and the track ability to stay 'in place' on/in its wheels.

Akin to the early 2000's shared body shaped Jag Aston Martins DB7/9's that when at roughly 62mph (or 72mph) the front wheels would briefly 'resonate' and bounce upwards with their susp'n arms due to wheels not being light enough - making them heavier worsened the steering's feel and made the grip more ponderous and switchable from over to under steer let alone the increased rate of wearing out of the front tyres that'd ensue - the problem was solved if you bourght their/some carbonfibre wheels - so I remember my automech head uni lecturer saying ...all alllegedly of course.
I allegedly don't know if this is still a problem with the DB7/9 nowerdays, likely still is at specific constant speeds unless you go for improved racing susp'n units or Electronic Active Susp'n ones and or with lighter wheels. ... ahem, sorry I digress, and now, back to tanks.
[cue the sound of hatches closing, engines starting and a round being loaded.]


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## wiking85 (Jul 2, 2014)

An interesting weight comparison between models:
https://de.wikipedia.org/wiki/Panzerkampfwagen_V_Panther#Technische_Daten
The original production version, the D-series weighed 43 tons, the A-series (which came after D for some reason) was 45 tons, and the final G-series weighed 44.8 tons.
So whatever changes were made were not initially as heavy; I think the turret was heavier than advertised, so when combined with the armor upgrade and resulting changes to the design it jumped it from 35/6 tons to 43. Without the armor upgrade in the front I think it probably would have entered production around 40 tons. Perhaps then with the Schmalturm in the F-series it would have been reduced to 38 or so tons as a result.


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## Shortround6 (Jul 2, 2014)

As above the armor upgrade in the front is about 1ton (2000lbs) give or take a few %. 

Planned engine or transmission/steering gear may not have worked as intended but that cannot be blamed on the armor upgrade. If an under 3% increase in weigh causes engine or transmission failure then something was wrong to begin with. 

The Panther is a large tank physically and expecting it to weigh only a few tons more than a Comet or late model Sherman or T-34/85 with their smaller hulls is just not reasonable. One foot of length on a tank that is 4.44 feet from hull floor to roof and using vertical side armor of 40mm is over 550lbs. The 15mm floor and sponson bottoms are about another 260lbs and the hull top deck (15mm?) is another 200lbs. The thicker upper hull and slope adds to the weight. 

Or think of a hypothetical tank 20ft long and 10 feet wide with 40mm armor all around. If you can cut 6in (152mm) from the height you can cut 1920lbs. 

Look at the size of a Panther (not just book dimensions but actual bulk) compared to the other three tanks and try to figure out how to make it that big and weigh only 35-36 tons.


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## razor1uk (Jul 2, 2014)

If they mad it from the future teleported aluminium armour of the M113 Gavin/Galvin? then it might weigh 35ish tons...

Mmm. thinking upon the reducing ferrous and non-ferrous metal ores/material shortages, then the ability for production vehicles to be made of consistent quality and metalurigical pieces similar to those of the prototype(s) c/w-ould add weight. 

Milder steel parts could be used on the internal bulkheads or non armoured structures, which as indicated by the increased proneness to impact fracturing, could suggest that the industry went from homogeneous armour to what sounds like face (outside surfaces) hardened armour.
Hence the fractures, that and having to substitute some rare to un-available elements that were replaced by different lesser elemnts or left out and replaced with additional carbon - producing more brittle and likely heavier for the same average armour resistance to projectile impact energies.


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## Shortround6 (Jul 2, 2014)

1950s/60s aluminium armor required about the same pounds per square ft as steel armor for the same protection. Weight savings came from the "skin" being between 2-3 times thicker than steel could become the "frame" and allowed the internal frame parts to be left out. 

Engine mounts, frame rails and bulkheads( firewalls) probably weren't armor steel anyway. Armor is expensive (many prototype tanks were made of "mild" steel) both to buy (make) and work. 

Difference in weight between different alloy steel armor is a bit overblown. Think about it. Very few steels used for armor contain any one alloying agent in quantities exceeding single digit percentages. In some cases you can use 5 different alloying agents and still not replace 5% of the iron/steel. Replacing 5% of your steel with an allying agent that is 10% heavier than steel changes the weight of you steel plate by 0.5%. Can you control the thickness of the plate (and weight) to 0.5% standards?

http://en.wikipedia.org/wiki/SAE_steel_grades

Stainless is somewhat different but then few people have tried to build a stainless steel tank


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## wiking85 (Nov 27, 2014)

Out of curiosity would a rear drive Panther have been shorter and therefore lighter?


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## tomo pauk (Nov 27, 2014)

Probably would not be any shorter, unless the engine is turned 90 deg, like it was done with T-44 vs. T-34. It might shave some height, though, sice there would not be the drive shaft between the engine and gearbox; that can also ammount to either less weight, or staying on the same weight, but featuring a bit thicker armor.


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## Denniss (Nov 30, 2014)

Panther would probably only be available in mid 44 or later because you have to develop everything engine/gearbox related stuff anew.


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## wiking85 (Nov 30, 2014)

Denniss said:


> Panther would probably only be available in mid 44 or later because you have to develop everything engine/gearbox related stuff anew.



Even if the 1941 VK3002 spec included rear drive?


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## Denniss (Nov 30, 2014)

Due to it's layout they had a lot of space for engine/gearbox in the rear, that wouldn't be possible in a standard tank layout.
Plus the transmission system used by DB was said to be very unreliable. No idea about the engine/gearbox layout used in it though.


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## wiking85 (Nov 30, 2014)

Denniss said:


> Due to it's layout they had a lot of space for engine/gearbox in the rear, that wouldn't be possible in a standard tank layout.
> Plus the transmission system used by DB was said to be very unreliable. No idea about the engine/gearbox layout used in it though.



Perhaps these will help, the first the Panther, the second the Jagdpanther


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## tomo pauk (Dec 1, 2014)

There was nothing excessive in the length of Panther's hull - it was in the ballpark with Comet, just a bit longer than Cromwell and T-34. KV-1's hull was a bit longer than Panther's.


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## wiking85 (Dec 1, 2014)

tomo pauk said:


> There was nothing excessive in the length of Panther's hull - it was in the ballpark with Comet, just a bit longer than Cromwell and T-34. KV-1's hull was a bit longer than Panther's.



I meant shorter in the sense of how high the tank was, not how long.


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## tomo pauk (Dec 1, 2014)

Doh 
Like above (post #51 here) - with 'all rear' powerpack, the drive shaft is no longer there, and the tank can be lower. That means lighter. However, there would be some length added, that means weight is added too, so the total weight loss would not be not so pronounced IMO.

edit: Hmm - looking at how the armor was thick on the hulls of the M 26 Pershing, KV and IS tanks, for negligible weight penalty, the 'all rear-drive Pather should've been an either better protected tank, or a much lighter one.


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## Denniss (Dec 1, 2014)

Again, you would need an all-new very compact transmission. this would have been very much impossible within the timeframe the Panther was rushed into production. It would have been different if such a transmission was already used in a somewhat comparable vehicle or a decision for a rear drive had been made in 1940/41.


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## tomo pauk (Dec 1, 2014)

Think you're right. 
Historically, the Panther have had some reliability issues, despite using the layout the German FV industry was well familiar. Those issues were more or less cured in a reasonable time. Going for an all-new system would not make it easier.


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## tomo pauk (Dec 1, 2014)

Think you're right. 
Historically, the Panther have had some reliability issues, despite using the layout the German FV industry was well familiar with. Those issues were more or less cured in a reasonable time. Going for an all-new system would not make it easier.


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## Denniss (Dec 1, 2014)

The drivetrain was layed out for a 35 tonne vehice, the Panther became a 'tad' heavier. They couldn't produce sufficient complex final drives capable to cope with the increased weight (as used in the Tiger series) so they had to stick with mass-producable less reliable final drives. They improved over time but stayed weak.
If they had opted for a rear drive in 40/41 they could have fixed this during development.


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## wiking85 (Dec 2, 2014)

Denniss said:


> The drivetrain was layed out for a 35 tonne vehice, the Panther became a 'tad' heavier. They couldn't produce sufficient complex final drives capable to cope with the increased weight (as used in the Tiger series) so they had to stick with mass-producable less reliable final drives. They improved over time but stayed weak.
> If they had opted for a rear drive in 40/41 they could have fixed this during development.


No, the chassis was designed around a 30 ton chassis and the first production model Panther weighed in at 43 tons, 13 tons over spec. The title of the project indicated what the weight was intended to be: 30 tons for VK30.02 (and .01). It was supposed to be able to handle up to 35 tons, but no more. They took the VK30.01 chassis, changed the armor layout and track width, added a heavier, larger engine, and several other tweeks, slapping a VK3601 (or perhaps VK4501) turret on the chassis, which was poorly laid out and too heavy, and then added even more armor on it. 
https://de.wikipedia.org/wiki/Panzerkampfwagen_V_Panther#Technische_Daten
The final model, the G-series, ended up weighing in at nearly 45 tons after fixing some of the mechanical issues. Part of the issue with the final drive was that there wasn't enough room to insert a bigger, stronger one, so they had to use what was available given the time constraints and the war situation.


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