The German E-Series of Tanks – By 1945 Germany was operating a number of different, complicated, time consuming and expensive vehicles. The German Ordinance Department set about on a new series of tanks known as the Entwicklung series aka E-Series, that were all based on a simpler more common design that would fulfil a number of existing roles.
The E-100
This was the proposed supper heavy tank and would have weighted in at 100+ tonnes. It was the only one to reach the prototype stage (hull) and its development had run parallel with the Maus. It was intended that the main gun would be a 152mm or 172mm calibre, with a coaxial 75mm gun. The engine of the King Tiger was used during the prototype stage, but a more powerful engine would have most likely been used should this beast have entered production.
The E-75 Heavy Tank
The E-75 would have been 75+ tonnes in weight and would have replaced the Tiger series in German service. Due to the secrecy and remaining mostly at the planning stage, various sources have speculated that the vehicle would have used either a 88mm or 105mm Main Gun in either a new or improved King Tiger Tank turret. The vehicle would have been powered by a Maybach HL 234 engine and was much more heavily armoured that the King.
The E-50 Medium Tank
Weighting in at roughly 50 tonnes, the vehicle would have replaced the Panther. Its hull was almost identical to that of the King Tiger and was much larger than the Panther. It had a new turret and like the rest of the series a conical suspension system which was less expensive and easier to manufacturer compared to the existing types in service.
Other lighter tanks were also proposed such as the T-25 and T-10.