A Paper Alternative to the Panzer IV/70

The performance of German armoured vehicles is often overestimated, particularly of those that remained on paper. It can be anywhere between interesting and sad to watch an attempt to turn a doodle on a napkin into an ultimate weapon that could have changed the balance of power. It is clear why this happened. The thing is that the first German documents to be declassified were the ones with the least value. These were the documents that saw the widest publication even though weapons prepared by other nations for 1945-46 had much more potential.

The "canonical" E-25. The cupola appeared here due to a mistake made by American intelligence.

The E-series is usually the main subject of these fantasies. However, a careful evaluation shows that these projects achieved very little. The E-100 superheavy tank was actually a resurrection of the Tiger-Maus, rejected back in late 1942. At least the E-100 ended up as an unfinished prototype. None of the other E-series projects made it even this far, including the E-25.

Only scraps of information about the E-25 survive.

Heinrich Kniepkamp, the head of development of tracked vehicle chassis at the 6th Department of the Weapons Office, initiated the development of the so called E-series (Entwicklung - development) in April of 1943. The cause of this project was the failure of unifying the Tiger III and Panther II as well as the desire to put new tank destroyers into production and make another attempt to displace Porsche’s Maus. The series consisted of the 10-15 ton E-10 light tank destroyer, 25-30 ton E-25 medium tank destroyer, the partially unified E-50 and E-75, and the aforementioned E-100.

Hermann Klaue, the head of E-25 development.

The projects were distributed between different companies. The E-25 was given to Süddeutsche Arguswerke in Karlsruhe. According to the post-war interrogation of Karl Jenschke, the head designer at Adlerwerke (who worked on the running gear of the E-50/75 as well as the E-100) it was Hermann Klaue who led the work on the E-25. The Süddeutsche Arguswerke factory deserves a special mention. It link to tank building was not direct. The factory didn't build tanks, but only transmission components, for instance brakes for the Panther and other vehicles on that chassis. It would not have been possible to produce a whole tank here. A part of the factory's equipment was evacuated to Brotterode in 1944 and in 1946 everything that was left was taken to the USSR.

Süddeutsche Arguswerke factory.

The appearance of such a vehicle in the medium class tells us several things. One is that the 6th Department did not wish to create a direct analogue to the Pz.Kpfw.IV. Another is that had the E-25 was gunning for the most numerous vehicle class in the German army, potentially replacing the Pz.Kpfw.IV, StuG, and Panzer IV/70.

One of the few genuine images of the E-25.

The prospective tank destroyer was similar to the Panzer IV/70, but on an original chassis. According to the E-series concept, the chassis had external suspension elements. An individual coil spring suspension was used. By tradition, the large (1 meter in diameter) road wheels were interleaved which spread out ground pressure. Another common factor among the E-series was a rear transmission. The engine was placed perpendicularly, which made the E-25 shorter than the Panzer IV/70 (V) but noticeably wider and somewhat taller.

The E-series concept had the suspension moved out of the hull, but as you can see here it's still partially inside.

Unlike the Pz.Kpfw.IV and StuG that had a top speed of no more than 40 kph, the E-25 was going to be much more mobile. Like the E-10, it would be powered by a 400 hp Maybach HL 100 engine or the even more powerful 550 hp Maybach HL 101. This would make the E-25 much faster than its predecessors. Some sources give a top speed of 57 kph, a very respectable value.

ZF transmission developed for the E-25 in July of 1944.

The level of protection raised some questions. 50 mm in the front and 30 on the sides was not a lot for 1944, especially since the same Panzer IV/70 had 80 mm. The armament was not finalized. One option was to use the 75 mm Pak 42 L/70 like on the Panzer IV/70(V), but the final choice could have been different.

Hermann Klaue developed this transmission.

Unlike the E-10 which is only documented in a sketch drawn from memory, the running gear layout of the E-25 and a diagram of a transmission with a semiautomatic gearbox designed by ZF survive. Hermann Klaue patented his transmission design after the war as well. Allegedly three hulls were ordered, but Alkett built the Jagdpanzer 38(d) rather than E-25. This is not surprising, as Alkett was ordered to shut down StuG 40 production and transition to the Jagdpanzer 38(d).

The armament was likely going to be the same as on the Panzer IV/70(V).

If the war didn't end by 1946 then this vehicle may have had a chance at life. At the very least, individual components had already been developed, unlike with the E-50/E-75. However, if one looks at the situation more soberly, it becomes more complicated. There was no shortage of such drafts around this time. In part, Porsche K.G. was working on a similar tank destroyer known as the Panzerkampfwagen Porsche (later as the Schwerer kleiner Panzerkampfwagen mit 10.5 cm).

The origin of the cupola. American intelligence conflated the E-25 and Schwerer kleiner Panzerkampfwagen mit 10.5 cm.

Porsche's project was much more thought out. This was not just a handful of components but a fully fledged design with detailed elements, including the armament and sights. Interestingly enough, American intelligence lumped projects developed at Porsche K.G. and Süddeutsche Arguswerke together, creating an E-25 with an AA cupola (which was equipped with the 3 cm MK 103 instead of the real 3 cm MK 108 to boot). This cupola was a signature element of Porsche's turretless tanks.

German production plans for 1945. No E-series here, but the Panzer IV/70 survives.

The most important thing was that Germany had 4 tank destroyers weighing about 25 tons in production at the same time. Actual production plans limited production to the Panzer IV/70 (V) and replaced the StuG 40 with the Jagdpanzer 38(d). There was not a hint of putting the E-25 into production. The E-25 belongs in the realm of video games and scale models (just make sure to fix the roof first), but anyone who considers it a serious candidate for production should try using a different glue.

Original article by Yuri Pasholok.