After having talked about the Sturmpanzer E-75, we will now take a further look to the E-Series using data from "Waffend und Geheimwaffen des deutschen Heeres 1933-1945" by Fritz Hahn.
The translation has been done mostly by Google Translator with later adjustment by hand so please bear with me any mistakes.
While the author did not participate in tank development, he worked on the V2 project and claims to have had access to the original papers of tank designs during WW2.
Some stuff has likely to be taken with a grain of salt and I will try to compare passages with Spielberger where possible.
So, without further ado:
The series started with the E-5, a fast and small two man tankette of 6 to 10 tons.
Several projects have been drawn under the name "wanze" (bug).
One particularly low model was built in the same pattern as the romanian tank destroyer "Marshal" with a 7.5 cm PAK 40 cannon.
BMW proposed a design of a 3550mm long vehicle powered by a 90HP 3.5 liter engine.
A workaround was the panzerjager Bren.
On a 4t English captured tankette 3 panzerschreck were mounted, making it effectively an ambush APC.
According to Hahn, the companies Bussing, Daimler, Steyr, and Weserhütte submitted drafts together for a one-or two-seater tank destroyer armed with the 8cm PAW, although no final design was approved.
The general inspector of the armored troops refused all these drafts on 19 march 1945 and also a so-called off-mg car.
In the latter, 870kg heavy, 2650mm long and 1600mm wide vehicle, the crew was housed lying.
This resulted in a tankette only 60cm high, with small armored doors, two machine guns and a flamethrower.
No mention of this tank has been made by Jentz, Doyle or Spielberger.
According to Hahn, E-10 was planned to be based on the raupenschlepper Ost plants.
The Klockner-Humboldt-Deutz plants in Ulm along with Denene was supposed to develop and manufacture the tank along with Steyr.
The company during the war converted the RSO tractor to the RSO/Pak 40 version but otherwise had no tank building experience.
The vehicle was supposed to be a light multipurpose armored vehicle and according to Hahn in October 1944 Hitler ordered the production of 2910 units, although apparently no final design was approved.
The E25 was planned to be developed into a tank destroyer and reconnaissance tank.
The company Argus developed a the vehicle similar to the jagdpanzer Hetzer.
The five built in Alkett were driven by the 12-cylinder Maybach HL 230 P 30, rated 700hp, designed to be able to reach 65 kilometers per hour.
This pretty much corresponds to Spielberger's version, whom also mentions 400 and 600 HP engines.
The 26.3-ton vehicle carried a four man crew and was armed with the 7.5 cm PAK L/70.
Additionally, there was the anti-aircraft flak a 2-cm in a small rotating tower.
Later versions were supposed to mount 10.5cm KWK L/68.
Here instead we diverge at least partially, as Spielberger mentions 75mm L/48, L/70 and a "high performance 10.5cm" cannon.
This, in my opinion, is a wrong interpretation by the author, let's see why.
This is a reconstruction of the basic design:
A 75mm L/70 gun has a 5.25m long barrel, while a 10.5cm L/68 would be almost 2m longer!
Taking into account existing WWII designs, this would leave us with two other candidates, the 10.5cm L/52 (5.46m, or the slightly shorter Krupp L/47 draft but this is scraping the bottom of the design barrel) and the 10H64, which was a much shorter cannon firing primarily HEAT munitions.
As the former was discarded already as non-standard army caliber, it is very likely that the latter would have been the choice.
For the E-50, the company was responsible Weserhütte in bad Oeynhausen, the tank was planned to replace the Panther.
It was supposed to be powered by a 800HP Maybach engine, pushing the 50.8-tonne vehicle at 60 kmh.
A new rotating turtet with a 8.8 cm Pak 42 was in development by Krupp.
Due to bombardments the manufacture of armored hulls slowed down several times and the conversion of a Tiger II hull was also not completed.
The E-75 used the same hull armor, but the interior was smaller due to stronger armor.
Here Weserhutte and Adler in Frankfurt ever had submitted a design.
The 60t heavy chassis used eight rollers per side over the six rollers of e-50.
The 10.5 cm L/68 was planned in the turret designed for E-50 as the main armament.
The 85t heavy assault gun variant was designed to use the new 15cm StuK 42 L/52, which fired a 42kg heavy tank shell.
The E-100 was the heaviest vehicle series that has been developed since June 1943 by the company Adler.
The 8690mm long and 4480mm wide chassis was almost finished by the end of the war.
The 1000mm wide tracks had a ground pressure of 1,43 kg per square cm.
As the engine the Maybach HL 295 was planned.
This 12-cylinder displacement of 29.6 liters was planned to reach 1050 hp and bring the 140t heavy E-100 to 40kmh.
The front armor was 200mm, while sides were 120mm thick.
The turret was about 52t heavy, using the 12.8 cm KWK L/55, with a frontal armor of 240mm.
As a six man crew was planned.
A jagdpanzer version armed with the 17cm L/50 STUK was planned.
A 71kg tank grenade was already available in this caliber.
All in all, Hahn seems to be either drawing on Spielberger as a source or having access to similar material.
While I doubt any deliberate forgery has been made, Hahn seems to have a marginal understanding of tank design and makes some wrong assumption in places.
Still, some details are useful in reconstructing the elusive E-series tanks, especially in association with writings left by Spielberger.
I sincerely hope this article picked your interest and welcome your comments as usual.