Friday 11 August 2017

Pz.Kpfw.II Ausf. D-E: Unlucky Torsion Bars

Worldwide tank building progressed rapidly in the second half of the 1930s. This can definitely be said about Germany's tank industry, which developed tank suspensions, along with everything else. Various experiments in this area led to widespread use of torsion bars. However, there is a tank in the history of Germany's tank design that was produced in large numbers, but it is rarely remembered. It ended up in a paradoxical situation where, instead of a technically superior tank, a tank with an old suspension returned into production. This was the PzII Ausf. D: a light tank that fought in its initial configuration for only a month.

Attempt at improvement

The first serious modernization of the PzII was designed by MAN by mid-July of 1936. Indexed PzII Ausf. c, it had noticeable differences from tanks of the first series. Instead of a Kleintraktor type suspension, a completely new suspension with five road wheels per side was designed. The converted suspension was better, and the larger road wheels were more reliable. Mass production of the PzII Ausf. c began in late summer of 1937.

According to Heinrich Kniepkamp, the improved suspension only solved a part of the problem. In addition, he considered leaf springs to be if not a thing of the past, then definitely far from progressive technology. Nobody knew how the new suspension would turn out, so Kniepkamp decided to play it safe. He picked a torsion bar suspension as an alternative, the same kind that proved itself on the Landsverk L-60 Swedish tank. 

The tank was Swedish, but its suspension had German roots. It was designed at Porsche K.G., under direction from Karl Rabe. Landsverk itself was subordinate to the German Gutehoffnungshütte, Aktienverein für Bergbau und Hüttenbetrieb (GHH), a company that MAN was directly connected to.

Experimental chassis on trials, 1937. Whether it was created by MAN or Krupp is an open question.

A decision to design a new chassis was made on January 27th, 1937. MAN was given the contract. However, the suspension was not the only thing that changes. The 6th Department of the Armament Directorate requested that the chassis be reworked, since the internal layout was inefficient. The engine, as well as the gearbox, were shifted to the right. The driver and radio operator's stations were roomy as a result, but the tank's front right corner was empty.

A new idea was to place the radio operator to the right of the driver, with the engine in the center of the engine compartment. The engine in this case was a Maybach V-shaped 8-cylinder 6.5 L engine, coupled with a 7-speed gearbox of the same company.

Krupp also tried to get its hands on the project. Its engineers presented a new La.S.100 variant with a new 130 hp air cooled Krupp M314 engine. It is not known how far work on this vehicle progressed. Nevertheless, there is a photograph of a chassis, dated 1937. The chassis is noticeably different from the one designed later by MAN. The number of road wheels was reduced to four, but their size was increased. The return rollers were removed.

Overall, this chassis was very similar to the one that was designed by Kniepkamp for the VK 3 t program (future PzI Ausf. C). It is likely that the tank would have had a torsion bar suspension, even though Krupp did not like it, preferring leaf springs.

MAN experimental chassis. The running gear is similar to that used on Kniepkamp's halftracks.

MAN was also working on their prototype, and its design makes it obvious that they were working closely with Kniepkamp. At the time, the engineer was promoting ideas that he implemented on halftracks: running gear with large diameter road wheels, rubber rims, and track links with lubricated joints and rubber pads. This running gear, combined with a torsion bar suspension and a semiautomatic Maybach S.R.G. gearbox noticeably improved mobility.

In order to free up space for two crewmen in the front, the new gearbox was coupled with the engine, connected to the main clutch by a long shaft. The driver and radio operator were very comfortable in their seats. Instead of a V-shaped engine, the vehicle, indexed La.S.138, used the 140 hp linear Maybach HL 62 TR engine, the same as on the PzII Ausf. c.

Diagram of the PzII Ausf. D chassis. You can see how much it differs from its predecessor.

Sadly, no reports about the trials of the La.S.138 chassis were preserved. However, it's obvious that somethign went wrong. Kniepkamp did not reject the idea of using a halftrack-like chassis, but the vehicle began to transform. The track links with rubber pads likely showed themselves as well as they did on the future PzI Ausf. C. The higher mass (compared to a halftrack) led to them wearing out quickly at high speeds. The idea of lubricated joints was also removed from the La.S.138. Instead, 300 mm wide and 100 mm pitch fully metallic tracks were developed, similar to those used on the PzIII

Other changes were made to the new tank's chassis. Since the driver's compartment changed, the configuration of the front plate was also altered. The complicated curved front was deleted, and replaced with flat plates. The number of final drive access hatches was increased to two, and the hatches themselves were now in two sections. In an emergency, they could be used to leave the tank. One cannot say that this was very convenient, but it was easier for the radio operator to exit like this than to go through the engine compartment like before.

As you can see, even the road wheels of the PzII Ausf. D and E were different.

The first four gearboxes were given to the creators of the new design in September of 1937. Around this time, new prototypes were built. ZF was the main subcontractor for production of SRG 14479 gearboxes. Overall, the first contract was made for 85 gearboxes.

Overall, the 6th Department looked favourably on the La.S.138. Specifically, Major Olbrich called the La.S.100 design poor at a meeting on August 18th, 1937, and expected the joint effort by MAN and Kniepkamp to be better. However, expectations and reality don't always match up.

First of all, the PzII Ausf. c and the PzII Ausf. A-C that followed were good tanks. Their suspension was reliable, and their characteristics matched the German armament system. It's not surprising that the tanks that were dismissed by Kniepkamp and his team turned out to be the most common tanks on the front lines.

Secondly, work on the La.S.138 was late. However, this was probably an advantage, since the front armour of the tank was increased to 30 mm as a result.

Thirdly, work wasn't going as smoothly as it seemed. There can be no other explanation for the fact that the Armament Directorate approved the development of a new tank, indexed VK 9.01 (tracked vehicle, 9 ton class, first prototype) on June 18th, 1938, right in the middle of the development of the new tank. MAN was responsible for the chassis, and the turret and turret platform would be built at Daimler-Benz.

The reasons for the new design are obvious. The La.S.138 turned out to be 2 tons heavier than the PzII Ausf. A-C, given the same dimensions. Of course, it had thicker, armour, but only in the front of the hull and turret platform. The turret was the same as on the PzII, with only 14.5 mm of armour. With applique armour and improvements, the mass of the precursors climbed to 9.5 tons. The La.S.138 had no reserve. In other words, aside from a higher top speed with the same engine, the tank had no advantages over the "inferior" La.S.100.

For light divisions

The start of work on the VK 9.01 did not mean that the La.S.138 was cancelled. In October of 1938, chassis with numbers V 8 and V 11 were shown to the representatives of the Armament Directorate, with Kniepkamp among them. These were, presumably, experimental prototypes, which were later indexed PzII Ausf. D and PzII Ausf. E. The Ausf. E had running gear that implemented Kniepkamp's ideas, but without rubber pads on the track links. The PzII Ausf. D had a radically different suspension than the one used in the initial concept. The drive sprockets and idlers were fully metallic, and the track links were completely different.

Mass production PzII Ausf. D in a training unit, summer of 1939.

The new batch of vehicles was indexed 8.Serie/La.S.138. Their armour was supplied by Deutsche Edelstahlwerke AG (DEW) from Hanover. ZF supplied the gearboxes: 93 were delivered in 1938, and three more in 1939. The PzII Ausf. D tanks built according to contract Nr.600 034 received serial numbers from 27001 to 27085.

The first tanks were assembled in October of 1938, but mass production began later, in early 1939. The final number of tanks built was much less than initially planned. Only 43 tanks were built before April 1939, after which production ceased.

Tanks on parade in Berlin. The tanks are loaded onto heavy Faun 900 trucks.

The fate of the PzII Ausf. E was even sadder. According to a report from March of 1939, the tanks, built according to contract Nr.600 030, were in the state of almost complete chassis by the end of the month. There were issues with track links and other running gear components. Seven PzII Ausf. E were ready in April of 1939, but only as chassis. By this time, the Armament Directorate realized that the La.S.138 with a 20 mm autocannon is no longer needed. Not a single PzII Ausf. E was assembled as initially intended. The serial numbers of these unfinished vehicles ranged from 27801 to 27808.

PzII Ausf. D, serial number 27009, from the 4th company, 67th Tank Battalion, transported by truck, 3rd Light Division. Poland, September 1st, 1939.

The tanks that were built never made it to regular Wehrmacht tank divisions. They were sent to special units: tank battalions transported by truck (Pz. Abt. verl.). Those, in turn, were included into light divisions, which were supposed to be highly mobile. The light divisions included not only the PzII Ausf. D, but earlier modifications, up to the Ausf. a/1. The Germans sent a lot of non-standard vehicles to these units, including, for example, former Czech LT vz. 35 and LT vz. 38 tanks. They were transported in Faun 900 trucks, which could lift 9 tons. One tank was in the truck bed, the other was towed behind the truck.

It is known that the PzII Ausf. D was included in the 66th Pz. Abt. verl. included in the 2nd Light Division, as well as the 67th Pz. Abt. verl. in the 3rd Light Division. There is also information about tanks of this type in the 33rd Pz. Abt. verl. in the 4th Light Division.

PzII Ausf. D bridgelayer, September of 1939.

The tanks were used in this way during the Polish campaign in September of 1939. At least one vehicle was used as a bridgelayer. The German bet on truck-borne tanks paid off only partially. The order to reform the light divisions into tank divisions speaks volumes. On October 18th, 1939, the 2nd Light Division became the 8th Tank Division, the 3rd Light became the 8th Tank, and the 4th Light, the 9th Tank.

It's worth mentioning that not a single PzII Ausf. D was lost in Poland. This is not an indicator of the tank's high effectiveness, but, rather, its infrequent use. The PzII Ausf. D was used by tank divisions until March 8th, 1940, when an order was given to remove them from service. The vehicles returned to German service in 1940, but in a whole different form.

Quick flamethrower

The Armament Directorate thought about the subsequent fate of the La.S.138 back in the start of 1939. Understanding that the replacement for the La.S.100 was far from the original idea, they decided to find a new purpose for the chassis. On January 21st, a decision was made to develop a flamethrower tank, named Pz.Kpfw.II(F) and indexed Sd.Kfz.122. Production of 90 vehicles of this type was envisioned.

The producer of the chassis remained the same, but the producer of all other equipment was different. This was Wegmann & Co from Kassel. The wagon building factory cooperated closely with Henschel & Sohn, but had no prior experience in tank building, with one small exception: the superheavy K-Wagen tank.

One of the first PzII (F).

Initially, the concept proposed to Wegmann was that of a two-man vehicle with a mass of 11 tons. Instead of the stock turret, a different one was installed, armed with an MG 34 machinegun. The tank was also armed with two flamethrowers, located independently of the turret. As a result of inspection of the first draft, some changes were made. The radio operator's position was returned, and the crew consisted of three men once more. In addition to his other duties, the radio operator fired one of the flamethrowers. The commander fired the second one.

Closeup of the flamethrower mount. The low range was compensated by high maneuverability of fire.

The tank had two flamethrowers, both of which, along with their tanks, were housed outside of the fighting compartment. The radio operator aimed the right flamethrower, and the commander aimed the left. The tank only contained the gas tanks that provided the required pressure. Each flamethrower was fed by a 160 L fuel tank, protected by armoured casings. The flamethrowers could be aimed in an arc of 90 degrees to the outer side, and 30 degrees to the inner. They could also elevate to 20 degrees and depress to 10 degrees. This resulted in impressive maneuverability of fire for a flamethrower.

However, the range was not high, only 35 meters, so the tank had to drive right up to its target. Each flamethrower had enough fuel for 40 2-3 second long shots. The MG 34 in a reworked turret served as auxiliary armament.

Diagram of the flamethrowers used on the PzII(F).

PzII Ausf. D and E chassis began to arrive in Kassel starting in April of 1939. 46 chassis arrived between April and August, and another 43 arrived in March of 1940 as tanks. Overall, 89 chassis were available for conversion to flamethrower tanks. The first experimental Panzerkampfwagen II (Flammenwerferwagen) made from mild steel was demonstrated to the Armament Directorate commission in July of 1939. The customer was satisfied, and Wegmann began preparations for mass production.

The same Deutsche Edelstahlwerke AG supplied armour plates for the converted turret platform and turret. Sets of armour began arriving from Hanover in the fall of 1930, and the order was completed in 1940.

Flamethower tank from the 100th Flamethrower Tank battalion. You can see that the flamethrower fuel tank is covered with a special casing.

Two of the first mass produced PzII (F) tanks were accepted by the customer in January of 1940. Rates of production gradually grew, and Wegmann delivered 20 vehicles by the end of April. However, there was an issue. The first tanks were tested starting in March, and a number of complaints was made. 20 PzII (F) tanks returned to Wegmann, where they were converted to meet the customer's specifications. This somewhat slowed down shipments in May. In the summer, Wegmann returned to its regular rates of production: 20-22 vehicles per month.

Shipments of the first batch finished in October of 1940. By then, 86 tanks were delivered, but for some reason, 87 were recorded in warehouse inventory. Presumably, the "extra" tank was the prototype. In January of 1941, two flamethrower tanks were lost for known reasons, and three new tanks were built in February. The total production run of PzII (F) was 89 mass produced tanks and one prototype. Their serial numbers remained the same as the "base" PzII Ausf. D and E.

Only two units used these tanks: the 100th and 101st Flamethrower Tank Battalions (Pz.Abt.(F)) formed in March and May of 1940, respectively. The 100th battalion received 43 PzII (F) on July 10th, 1940, and it was deemed combat ready on the 15th. The unit participated in exercises that were meant to be the prologue to Operation Sea Lion (invasion of Great Britain).

The 101st Flamethrower Tank Battalion had to wait for its materiel. It receives its first tanks on July 11th, but the battalion was only completely equipped with 42 PzII (F) in September. It was deemed combat ready on October 10th, 1940.

Column of the 101st battalion, Belarus, June 1941. A captured Kreuzer Panzerkampfwagen Mk IV 744 (e) can be seen in the column. On June 22nd, the battalion had 9 of them.

The battalions had a mixed structure. According to TO&E K.St.N. 1177 issued on February 1st, 1941, the flamethrower tank company had 19 tanks, out of which 12 had flamethrowers. Commanders' tanks and tanks from the 4th platoon were regular PzIIs with cannons. 

In reality, things were more interesting. By February of 1941, a company of captured British tanks was included into the 100th battalion, Beutepanzer-Kompanie (e), which had 9 Kreuzer Panzerkampfwagen Mk IV 744 (e). They were converted, receiving tracks from the PzII Ausf. D. Formally, the tanks were not there as of June 18th, 1941. The battalion contained 24 PzIIs, 42 PzII (F), 5 PzIIIs, and one commander's tank.

The 101st battalion had identical armament, but one PzII more. All PzII (F) on the PzII Ausf. E chassis ended up in this unit. These tanks had two types of track links. Some tanks had track links with rubber pads, and on some of them, the pads were gone. These were not products of individual creativity from the tankers, but factory made vehicles. The flamethrower tanks were also modified: additional smoke grenade launchers were installed.

Captured PzII (F) on the PzII Ausf. E chassis at Kubinka, September 1941.

At the start of combat against the USSR, the 100th Flamethrower Tank Battalion was assigned to the 18th Tank Division. In its ranks, it crossed Belarus and continued on, ending up at Moscow's gates in mid-October. By October 20th, only 7 remained out of 42 flamethrower tanks. A decision was made to withdraw the battalion from the front lines on November 5th.

This did not mean that the war was over for flamethrower tanks. The battalion's vehicles, including two PzII, 2 PzII (F) and one PzIII, was handed over to the 18th Tank Division. It is not known how long they fought for afterwards.

The rubber pads wore out significantly during battles.

The 101st Flamethrower Tank Battalion was subordinate to the 3rd Tank Group. It began combat in the Baltics, and then also ended up in Belarus. Specifically, on June 28th, the 3rd Tank Group participated in the capture of Minsk. The flamethrower tanks also took part in the tank battles for Lepel and Senno. Later, they fought in Smolensk oblast.

Likely, this is where a tank from the 3rd company was captured by the Red Army. A tank with tactical number 311 was sent to the NIIBT Proving Grounds at Kubinka, where it was studied. A description of the flamethrower was composed, since it was a very original design. However, there was no interest in copying it on behalf of the USSR.

The same tank from behind. The markings on the back of the turret are characteristic of the 101st Flamethrower Tank Battalion.

According to documents, there were only five flamethrower tanks left in the 101st battalion on November 8th, 1941. In reality, that was not quite the case. According to existing date, the battalion had 10 PzIIs, 12 PzII (F)s, and two PzIIIs on November 18th. In addition, the flamethrower tanks fought at Volokolamsk on November 16th. Later, the battalion's tanks were handed over to the 2nd Tank Division, but the flamethrower tanks were quickly abandoned. Officially, the battalion left the front lines on December 8th, but in reality, its tanks were being used by the 2nd Tank Division for several weeks by that point. One can say for certain that the combat career of the PzII (F) was done by the start of December of 1941.

Abandoned PzII (F) near Volokolamsk. Early December 1941.

The names used in reference to these vehicles deserve a separate mention. Officially, they were called Pz.Kpfw.II(F). In documents, they were also called Panzer II Flamm and Pz.Kpfw.II (Fl). Meanwhile, they are most often called Flammpanzer II or Flamingo in literature. These names have no relation to reality.

In March of 1940, MAN raised the issue of building 150 La.S.138 chassis, but the military replied only a year later, when a contract for Pz.Kpfw.II (Flamm) of the second series was signed. The start of the batch was planned for August of 1941, and it would be completed in February of 1942. According to Panzerprogramm 41, the Wehrmacht would have 250 flamethrower tanks on the La.S.138 platform in total. However, the completion date shifted forward to April of 1942. As for the start of production, it only began in August of 1941.

One of the first Pz.Kpfw.II (Flamm) Ausf. B chassis. The running gear underwent noticeable changes, especially the tracks, drive sprockets, and idlers.

The tanks, indexed Pz.Kpfw.II (Flamm) Ausf. B, were somewhat different from the tanks of the first series. First of all, this meant the suspension. An improved track link was designed, the idler and drive sprocket were changed. In order to separate the old tank and the new one, the PzII Ausf. D was split into Ausf. D1 and Ausf. D2. It's worth noting that PzII Ausf. D2 were never built into regular tanks. They were initially only produced as chassis for the PzII (F) Ausf. B.

One of a few photographs of the PzII (F) Ausf. B. Soon after the start of production, they were converted into tank destroyers.

52 PzII (F) Ausf. B were built in total. The tanks received serial numbers ranging from 27101 to 21252. Three final tanks were built in March of 1942, after which production ceased. The tanks ended up in training units, but they were not fated to fight, at least as flamethrower tanks. After careful study of the experience of using the PzII (F) in combat, German command decided that production wasn't worth it. Tanks that were already built were sent to be converted.

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