Panzerkampfwagen auf Einheitsfahrgestell III/IV

[Deleted member 1487]

http://ww2drawings.jexiste.fr/Files/1-Vehicles/Axis/1-Germany/02-mPanzers/PzKpfw3-4/PzKpfw3-4.htm

What if instead of the Panzer III and IV chassis the Germans, upon developing the Geschützwagen III/IV chassis, phased out their existing production of the earlier types and adopted the new, combined parts chassis that took elements of both the Pz III and IV and combined them into one standardized Panzer?
It proved to be an excellent gun platform, being used for both the Nashorn TD and Hummel SP artillery:
http://en.wikipedia.org/wiki/Nashorn
http://en.wikipedia.org/wiki/Hummel_(artillery)

Apparently it could have also turret mounted the 7.5cm L/70 tank gun, which was the same weapon as the Panther. Because it utilized existing parts, required far less retooling for a new type of chassis, and could be maintained by mechanics familiar with the existing Pz IIIs and IVs it would be relatively easy to transition to, while having greater upgrade potential than existing models, more flexibility for conversions to TDs/SP Art, and was much cheaper and easier to produce than the Panther or Tiger, while having similar production costs to the Pz IV.

Some production would be lost in the transition, but IMHO it makes more sense to switch over than stick with the aging and limited variety of models that the Germans used IOTL.

Here is a picture of what a Pz III/IV would look like:

 

[AMF]

Apparently it could have also turret mounted the 7.5cm L/70 tank gun, which was the same weapon as the Panther.

Are you sure about this? The cannon in the drawing looks more like the 7,5cm L/48 to me, the same as on an OTL Pz IV from the F2 model onwards. I doubt that a different chassis would have made the bigger gun possible, since the designers would be restricted by the same width of the vehicle, resulting in the same diameter of the turret ring, in turn resulting in the same restrictions on the turret and the gun it can accomodate.

Some production would be lost in the transition, but IMHO it makes more sense to switch over than stick with the aging and limited variety of models that the Germans used IOTL.

I do not know whether the change you mention would be worthwhile. It might very well end up with still another type of chassis on top of the many existing ones. It would have been better (from the Nazi leadership point of view) to have one chassis for the Panzer III and IV from the beginning.
One can also see that the tank has sloped frontal armor. This was indeed proposed even for a standard chassis Panzer IV, while there were also proposals (I think) for a tank with the chassis you mention, that had the stepped front as the standard Panzer IV.

 

[Deleted member 1487]

Are you sure about this? The cannon in the drawing looks more like the 7,5cm L/48 to me, the same as on an OTL Pz IV from the F2 model onwards. I doubt that a different chassis would have made the bigger gun possible, since the designers would be restricted by the same width of the vehicle, resulting in the same diameter of the turret ring, in turn resulting in the same restrictions on the turret and the gun it can accomodate.

The picture doesn't show the turret I'm talking about, just a mockup of the 'basic' type. The dimensions IIRC were actually longer and wider than the Pz IV, which enabled it to mount the 88mm L/71 of the Nashorn and the 15cm howitzer of the Hummel, which the Pz IV chassis could not do. IIRC the Grille development of the Pz IV maxed out with the 88mm Kwk 36 L/56 that the Tiger used. The final chassis would be somewhat different from the existing Pz IV in that it would be larger overall and have slopped frontal armor.

I do not know whether the change you mention would be worthwhile. It might very well end up with still another type of chassis on top of the many existing ones. It would have been better (from the Nazi leadership point of view) to have one chassis for the Panzer III and IV from the beginning.
One can also see that the tank has sloped frontal armor. This was indeed proposed even for a standard chassis Panzer IV, while there were also proposals (I think) for a tank with the chassis you mention, that had the stepped front as the standard Panzer IV.

The Pz IV K did have sloped armor....in 1944. But it was overburdened by weight increases for its size and couldn't handle the changes. It was too little too late and not a performance enhancement.
The Pz III/IV would be in 1942 when Pz IV production was still low and the Nibelungwerk was just coming online. If the 'unified chassis' were selected for production at that huge armor factory from the beginning of its production (1942), it would replace the Pz IV instantly as the majority of Pz IVs historically came from that factory. I think the Pz IV could be phased out by 1943 and the Pz III by 1944.
For example the Pz IV chassis was only produced to the tune of 800+ models in 1942, at least half at the Nibelungenwerk; if the Pz III/IV is the selected model for that factory, which IOTL produced some 4700 Pz IVs, it could start in 1942 and quickly supplant the other two major models provided it's phased in gradually over the next two years to prevent major disruptions in production.
Because so much of it is so similar to the existing Panzers, tooling should not require the usual 3-6 months. What was lacking was a figure pushing for efficiency in production of tanks by limiting type proliferation, a major problem in German production.

 

[AMF]

Okay, that is a lot of information I did not have !

 

[Deleted member 1487]

http://en.wikipedia.org/wiki/German...oduction_during_World_War_II#Total_production

So let's say that the German armaments Czar (Fritz Todt in 1940) orders a unified chassis for all purposes in 1939-1940 that is ready by March 1941. They phase out all production in favor of the new single chassis starting in June 1941 (after which time it was hard to get replacements to the front and didn't infere with the build up for Barbarossa), which allows for a massive economy of scale, as there is but a single type to produce parts for until the Tiger arrives in limited numbers in late 1942. Even then its only some 25 units per month, so hardly makes a dent in production resources/labor. The Panther shows up in limited numbers in early 1943 until later in the year when it starts taking over more production.

By eliminating the Pz II, 38(t), Pz III and IV, Germany saves some 30k+ of the less useful models from mid-1941 on, which can then be focused on a single chassis probably netting Germany over 10k additional chassis over the course of the war. Plus the chassis would be more effective, able to mount more powerful armament AND have better armor than the historical models (the Einheitsfahrgestell had sloped frontal armor). By 1943 this could seriously make a major difference by having the Pz III phased out and an essentially better Pz IV in service, all mounting the 75mm L/48 or potentially even L/71. Having more chassis of the bigger Einheitsfahrgestell would mean more 88mm L/71 tank destroyers like the Nashorn around too, not to mention more SP artillery. It could mount more armor than the Pz III or 38(t) chassis for TDs, while having better stability for the longer barreled 75mm and 88mm guns for the Jagdpanzer versions (the Pz IV chassis had serious front loading issues).

So potentially I think this could, because of having better tanks in the field and more of them, blunt the Soviet offensive successes after Kursk (though historically they took a ton of losses in the process), while enabling the Germans to make good their armor losses much more readily, while probably taking significantly less than what historically occurred. This could mean some major changes in 1943-44 in the East at least, with German forces keeping the Soviets further East for longer and potentially avoiding some of the pocket battles that hastened the collapse of the Wehrmacht in the East.

Am I off base suggesting that having more and better tanks from 1942 on would change the course of the war from at least 1943? Perhaps by having extra Panzers produced and divesting themselves of the older models, Germany can properly equip her allies like Romania, which would enable them to better handle the Soviet Uranus offensive?

 

[Somua2]

I think you make good points

It's counterintuitive, but the Panzer IV was adopted before the Panzer III was approved for mass production in 1939. Wouldn't it have been a kick if the Germans started with the III/IV in 1939 (maybe having it developed simultaneously as a back up and alternative)?

I think Barbarossa and the Western Desert would have really felt an impact. Really could have cost the Russians worse casualties during the warm weather and blunted the Russian Winter Offensive. I bet Rommel could have decimated British armor with that weapon as well.

 

[Deleted member 1487]

It's counterintuitive, but the Panzer IV was adopted before the Panzer III was approved for mass production in 1939. Wouldn't it have been a kick if the Germans started with the III/IV in 1939 (maybe having it developed simultaneously as a back up and alternative)?

I think Barbarossa and the Western Desert would have really felt an impact. Really could have cost the Russians worse casualties during the warm weather and blunted the Russian Winter Offensive. I bet Rommel could have decimated British armor with that weapon as well.

The more tanks the better for Germany. It also doesn't hurt if they are better than the historical models.

 

[BeardedHoplite]

So it uses the chassis of a Panzer III and the turret of a IV?

 

[Deleted member 1487]

So it uses the chassis of a Panzer III and the turret of a IV?

No, its a new chassis that is 25 ton class and was longer and wider than the Pz IV. It used the engine of the Pz IV and suspension of the Pz III; one of the two provided the transmission and a few other parts. The turret of course was from the Pz IV.