The long evolution of Henschel designs

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The famous Tiger tank wasn’t created in a day.

 Durchbruchswagen

Its roots can be traced back to January 1937, when Wa Pruef 6 asked Henschel to develop designs for a 30 ton tank armed with a 7,5cm cannon.

The Panzer project was initially called B.W. (Begleit Wagen verstaerkt, reinforced escort tank), implying a similar role as the similarly named Panzer IV design.
The name and intended tactical role didn’t last long and on 28 April 1937 it was changed to D.W., Durchbruchswagen, or breaktrough tank.

The design specified a 30 ton tank with 50mm armor all around, pushed by a 300HP MB HL-120TRM to a maximum speed of 35km/h and the 75mm L/24 cannon.
Turret ring was 1500mm, close to Panzer III specs meaning it could accept pretty much the same turrets and guns.

VK 30.01 (H)

 Following D.W. development, between 1938 and 1939 it was decided to keep the same general specs, but for a panzer with roughly the same internal space as Panzer IV.
The initial engine was the 300HP MB HL 116, proposed to be upgraded either to a 375HP Maybach HL190 or a 400HP MB HL 150 which would have brought HP/ton from 10 to either 12,5 or slightly over 13.

Krupp redesigned the turret to be compatible with minor changes with both VK 30.01 and its heavier cousin the VK 65.01 just by increasing armor thickness, while the armament for now was still the 75mm L/24 howitzer.

 By 1941 however this was quickly becoming obsolete, so up-gunning attempts were considered.
At first a 7,5cm L/34,5 was considered, but Krupp replied it couldn’t be mounted without extensive turret modifications.
The 5cm L/50 or L/60 could be considered instead, as modifications required were quite less demanding.

The conical 7.5cm Waffe 0725 was proposed but discarded as it couldn’t be installed as well.
By December 1941 Krupp figured out a way to fit the 75mm L/43 although with some ergonomic difficulties for the commander, while on January 1942 they replied the 7,5cm KWK 44 could be fitted only with numerous design difficulties and what basically amounted to a turret redesign.

All in all, the project was stopped because it failed to offer a valid improvement over the now battle tested Panzer IV and the design itself was becoming outdated and difficult to upgrade.

VK 65.01 (H)

 

Developed in parallel to the VK 30.01, VK 65.01 was to be a heavy breakthrough tank.
The focus was put on protection, with armor upgraded to 80mm all around to give protection from 5cm cannons, while top speed was lowered to 20-25kmh.

The turret was to share components and general design with D.W/VK 3001, only with thicker armor.
In January 1939 Krupp proposed 3 different guns for the tank: the basic 75mm L/24, a 75mm L/40 and a 105mm L/20.
75mm cannons were preferred due to better performance against bunkers and easier to store ammunition.

The tank was to be truly massive, with a hull that had to be dismounted in 3 pieces in order to fit railway profile.
A Maybach HL224 engine rated 600HP was chosen as power plant,  pushing the 65 tons tank at 20kmh.

The project was scrapped after the defeat of France because of bridge restrictions and because Wa Pruef 6 felt that tanks above 30 tons were operationally of limited use.

VK 36.01 (H)

In june 1940 specifics for a 30 ton class tank were laid, including a 10,5cm cannon as main armament.
Later on, the need of a high penetration weapon resulted in the proposal of mounting the Konical 7,5cm Waffe 0725.

The turret deserves a bit of attention on itself:

In 1939 a turret with 100mm armor mounting a 10,5cm cannon was developed, for a speculative design called A.W., Artilleriewagen.
Unfortunately no design specs survive other than the fact it would have been in the 80 tons class.
As tanks over 30 tons were deemed unsuitable for army needs, the panzer design was scrapped, while Krupp was asked to adapt the turret design (now finalized to use the 10,5cm LEFH 18) to the D.W. chassis.
This was achieved by reducing armor to 80mm front and 50mm sides, with an 80mm thick mantlet.

The D.W./VK3001 was then redesigned to take this improved turret, with increased weight to 36 tons.
The initial design called for 80mm frontal armor, 50mm side armor and was powered by a 450HP Maybach HL 174 engine.

Requests for up-armoring came up soon enough and the design was brought to 100mm frontal armor and 60mm sides, bringing the tank up to 40 tons.
Tungsten shortages brought the project to a halt, especially as the turret ring couldn’t support the 88mm L/56 gun, making development switch priority to the larger and heavier VK 45.01 design, the well known Tiger.

This wasn’t the death of the plans though, as in 1942 the 7,5cm L/70 was proposed for the design along with the Tiger and VK 30.02, although after this details are lost in Tiger’s development.
The only produced VK 36.01 chassis ended up as towing tractor, while the 6 turrets produced for it became part or the atlantic wall.

VK 45.01 (H), aka the Tiger

 

 In May 1941 Henschel was awarded a contract to redesign the VK 36.01 chassis so that it would house a turret suitable to mount the 8,8cm KWK, already developed for the Porsche chassis.
The redrawn specs brought the project to 45 tons, with many components taken from the VK 36.01, while side armor was raised to 80mm.

A new engine was specified, the 600HP Maybach HL 210, while a Rheinmetall turret suitable to house a 75mm L/60 gun, then 75mm L/70 was also considered.
A conversion to use the 88mm L/71 was also planned for late 1942, but never carried out.

 

From Tiger to Tiger II, VK 45.02/45.03 (H)

 

 In April 1942 the first conceptual drawings were made by Henschel for an upgraded VK 45.02 (H) Tiger mounting an 88mm L/71 cannon.
At first as many automotive components as possible were taken from the VK 45.01 (H) and together with Krupp a turret for the 88mm L/71 was designed.
In February 1943 Henschel was ordered to redesign the tank in order to maximize compatibility with Panther components.
This project was called VK 45.03 (H) Tiger II.

At the same time, Speer requested compatibility with the newer Panther II project, resulting in the VK 45.03 (H) Tiger III proposal, sharing transmission, drivetrain and the Maybach HL 230 engine rated 700HP, where Panther II would use 7 roadwheels, while Tiger III used 9.
In all these early drafts the hull chassis was set to 100mm armor sloped at 50°, with Guderian mentioning a proposal to bring it to 120mm.

Hitler himself gave the final specs armor specs, declaring the frontal armor should be 150mm, while side will be set to 80mm.
In the end, the winner new Tiger would be the Tiger III (renamed as Tiger II), with the initial turret taken from the Porsche VK 45.02 (P) project.

Tiger II

 The first 50 Tiger II hulls were coupled with the turret left from the VK 45.02 (P) development.
The rounded shape, while good for deflection, left a shot trap.

In October 1942 it was considered possible to start serial production in September 1943, however troubles in incorporating Panther II parts meant the first Tiger II was delivered only in November 1943.

From October 1943 to May 1944 only 38 Tiger II were produced, while production was slowed down again in October 1944 by extensive bombing raids, resulting a total of 283 Tiger II produced by end of the war.

A few modifications did not reach the end of the war:

- The Maybach HL 234 Engine rated at 800HP
- An alternative Argus-Man Engine, also rated at 800 HP
- A stabilized version of the 88mm L/71 and turret rangefinder
- A turret mounted MG 42
- An upgunned version, using the 10,5cm KWK L/68

 Beyond this, the E-series…

Which will be subject of a further article.

As you can see, from the Humble D.W. to the mighty Tiger II, Henschel produced a fine tank evolution.

I sincerely hope you enjoyed reading this and will meet you in our next article!

About Zarax

Wot: Zarax999 (EU Server)

69 thoughts on “The long evolution of Henschel designs”

  3. “From October 1943 to May 1944 only 38 Tiger II were produced, while production was slowed down again in October 1944 by extensive bombing raids, resulting a total of 283 Tiger II produced by end of the war.”

    I thought the number of tanks was between 450 and 500 produced in total?

  4. VK 45.02(H) was to feature sloping armor(50 to 60 deg.) and was to feature a slit for a MG instead of a MG mount. I think that is worth mentioning.

    Would the VK 45.02(H) have Tiger’s turret?

  5. What’s with the tetris zigzag (dont know name) block looking shape of front armor?
    Didn’t they realize that sloped armor gives more effective protection with same weight?

    Very good article. Looking forward to E-series.

    • IIRC that’s called “stepped hull front”, if you’re referring to what I think you mean.

      Apparently German tank designers were long similar to their Brit colleagues in that as far as they were concerned sloped armour only happened to other people. *shrug* Beats me why, the basic principle was well known already when warfare mostly boiled down to smacking the other guy upside the head.

      • The CSS Virgina (USS Merrimack) was one of the early employments of sloped armor. It was also used at the time on early rail guns that plied the rail lines on both sides.

        NEMO.

        • On a smaller scale the principle has been exploited in helmets and shields since the Bronze Age and in body armour at least since the invention of the solid steel cuirass in the Middle Ages. Fortress engineering joined in pretty soon after siege artillery became a major factor.

    • That stepped hull construction might have a few advantages over sloped armor as far as ergonomics and maintanance goes. For starters it was easier to install a vision block for the driver in it without significantly weakening the construction. Also, the horizontal plate could be much thinner and removable to allow easier transmission access. Remember – in panther and tiger 2 tanks, you had to strip a big chunk of the tank just to remove the thing.

      • Given that the German front hulls long tended to have the drivers visor right in the vertical plate (which occasionally cost the men dearly) and further compromised the integrity of the main glacis plate with the obligatory bow MG mount, eh. And the Americans certainly seemed to find it perfectly doable to combine a relatively easily accessible frontal transmission unit with a sloped glacis…

        Also I’d point out that if nothing else the “stepped” hull was considerably more complicated to assemble than the ultimately relatively straightforward sloped type, requiring multiple separate plates and that many more weld seams and God knows what else.

        • Don’t comment something you don’t know anything about.

          It didn’t compromise anything. Look at the specifications. German engineers always reinforced such areas with additional armor (for example: Tiger 1 frontal armor nominal thickness:100mm; driver’s visor+area around it: 120mm, and driver’s visor could be lowered in combat situations). The technical term is “edge effect” I believe. Zarax can clarify further if necessary. Stepped hulls were used with crew ergonomics in mind (among other things). German tank philosophy was to engage enemy armor at distances at which it could not retaliate effectively, and they were appropriately equipped. And at those ranges it doesn’t matter if your armor was angled or not. “Legendary” T-34 despite huge effort put in achieving “diamond” shape (at expense of everything else) still suffered horrendous losses (80+%). Even today tanks have vertical sides and rear, poorly angled glacis, some have flat turrets etc.

          • Visors often had a ball mount to reduce any vulnerabilities, the visor opened on Elefant for example had 300mm armor in total!

        • *shrug* Tell that to the Pz IV driver at Stonne who got his head blown off when a 25mm shell came in through the slit in the visor. Hardly a common sort of occurrence but anyway.

          Also I don’t think you know what the “edge effect” is; neither did period tank designers understand it properly, fair enough, but even superficial familiarity with structural engineering would seem to suggest making holes in something at the very least isn’t going to *strenghten* it.
          Which is one reason why modern tanks’ glacis plates are as smooth and unbroken as the designers can make them.

          Also fuck ergonomics, I’m willing to bet 5€ the main practical reason for the stepped nose was simply to fit in the transmission unit at the front of the tank. Didn’t hurt that it kind of intuitively follows the shape of a seated man, which is presumably why the same kept turning up in several rear-driven British and Soviet tanks.

          May I also ask you to not try bringing irrelevant not to mention flat-out *false* this-versus-that comparisions to the discussion? Thanks.

            • Your contribution is very importa- no scratch that, your irrelevant bleating is devoid of both content and merit.

  6. Now Zarax knows how to write properly, informative, and not intending to start a flame war for their own personal enjoyment like another writer here.

    • As opposed to pathetic, bitter little whiners who cannot process opinions nevermind now empirical evidence contrary to their dearly held preconceptions?

      • You really are a special individual. Did this person put flame bating material in this article? Did this writer taunt, tease, and flame people in the comments? The answer is “no” to both. That is a “FACT” in which you love so much, chump.

      • Aww .. When someone writes something contrary to your dearly held beliefs it becomes “intending to to start a flame war” .
        Well I admit the tears generated from aforementioned articles are very entertaining .

    • I don’t mind writers willing to demolish popular myths with facts, regardless of how many whining fanboys the tanks behind those myths have. I hope he continues. :)

  7. ” The first 50 Tiger II hulls were coupled with the turret left from the VK 45.02 (P) development.
    The rounded shape, while good for deflection, left a shot trap.”

    Where is the shot trap in the tiger 2 turret? Underside of the gun?

      • Yep. As to HOW they didn’t see the shot trap when designed IDK… You think they would have somebody who was a tanker… look it over. But I know how their community system worked. Read about it before. Still cant believe such stuff slipped through but it happens even in American tanks. Its very hard to get the design correct, 100%, the first time around.

        • They seemed to tolerate a rather similar shot trap in the Panther for quite a while though… IIRC wasn’t the main practical reason to drop the “Porsche” turret the unnecessarily complex shape (what with the commander’s semi-protruding “tower” along one side) which made for slow manufacure?

            • The shot trap was not there because on the Porche design the was an armor band on the top of the hull that protected the turret from the front, and when aimed to the side the “shot trap” was over the hull side and thus no longer a “shot trap”.

              When installed on the Tiger II hull = shot trap.

              Panther had the same issue earlier in development and this was after field data was relieved on the problem, so the Germans were addressing the issue .

  10. *sigh* Looks like I have some cleaning to do.

    Edit: There. I banned the nazi and cleaned his “contributions”. You can go worship Hitler and post anti-semitic crap somewhere else.

  12. its good to read an article on the evolution of an idea into an concept, anyone know why interleaved suspension were chosen for the Tiger and Panther?

    • superior ground resistance over the classic layout. notice how boxy, e.g. short Tiger I is. One of the reasons was the undercarriage layout.
      IIRC, the ground pressure of T1 was exceptionally low (1kg for square cm, compare to t34/85 of ~.80kg for square cm, that was half as heavy!) for its weight making it tactically maneurable (terrain passability) well beyond of what you would expect from a heavy tank.

      • …except none of them were anything like SHORT. The Tiger I had ~6.4m hull, the Panther ~6.9m and the Kingtiger ~7.4m (compare to ~5.8m for the Sherman). The first was, however, rather broad relative to its lenght hence the “squat” appereance.

        Ground pressure is ultimately dictated by the contact area, ie. track dimensions. The “big cats” simply had long and wide ones. The interleaved and overlapping suspension AFAIK had little relevance to THAT, rather – if I’ve understood correctly – it spread the vehicle’s weight more evenly on the *tracks* which apparently gave a relatively smooth ride over bumps.
        More practically it made for less wear for each roadwheel, which was kind of a good thing as Germany was mostly stuck with synthetic rubber for their coating which apparently had endurance issues.

      • Then why doesn’t it perform like that in WoT? From my experience, while certainly not really BAD for a Heavy Tank as far as mobility is concerned, it was still rather sluggish, especially in speed. The actual Tiger I was as fast as an M4 Sherman (until they geared down the engine due to maintenance issues, but since reliability isn’t taken into account in WoT, there’s no reason why it shouldn’t be able to hit top speed)

  13. “while on January 1942 they replied the 7,5cm KWK 44 could be fitted ”

    Doesn’t 44 means that it was developed around 1944?

    • I think that was wishful thinking by Krupp, the 105mm was discarded also because of the necessity of a 2nd loader and resulting poor turret ergonomics.