More info on the E-25 tankhunter.
Panzerkampfwagen E25
The German E series of simplified development tanks designed towards the end of the war. The vehicle described here is the E-25, a squat, ugly little tank somewhat reminiscent in shape to the Jagdpanzer 38(t) Hetzer which it was designed to replace, along with the Jagdpanzer IV Lang, the other Panzer III/IV based Sturmgeschutz/Panzerjager types and all other self propelled anti-tank gun chassis in service. Most of these vehicles carried out roughly the same task but were vastly different in design and construction and the E-25 would have rationalised them down to just one simple vehicle. As usual the information available is minimal so I have had to make educated guesses as to a lot of the details. Also my German isn’t too hot either. I managed to master Cromwell Model’s E-25 from what was available, though.
Work on the E series started in 1943 under the direction of Waffenprufamt 6 (WaPruAmt 6) headed by General H.E. Kniepkamp, a capable and prolific engineer and good administrator. A direct translation of this organisation is “Weapon test establishment, section 6”. The firms involved in the E series were Klockner-Humbolt-Deutz of Ulm, makers of the Diesel powered RSO/03, Argus of Karlsruhe, Adler of Frankfurt, and Weserhuette of Bad Oeyenhausen. They were to design respectively tanks in the 10, 25, 50, and 75 ton weight brackets. Adler were also directed to design a super heavy tank in the 100 ton class, which was actually built.
Drawing by H. Doyle
Argus had the task of making the E-25, nominally weighing 25 tonnes. It was to be a low, well armoured and agile tank destroyer taking the place of the Jagdpanzer IV Lang which was too large and fairly complicated to build. Armament was to be the 7.5 cm L/70 gun (as fitted to the Panther, Jagdpanzer IV, etc) which was a well proven weapon effective against all Allied tanks of the time. It may have been replaced in service with a new weapon designed by Krupp and Skoda as the 7.5 cm KwK 44 L/70 for the Schmalturm armed Panther F and featured a concentric recoil mechanism. This dispensed with the large cylinders on top of the gun barrel and would have enabled a much smaller mantlet than that of the Jagdpanzer IV Lang’s PaK 42 L/70 to be fitted. Skoda were working on an auto loader which would fire 40 rounds a minute and it had been test fired by the end of the war. In reality of course that rate of fire would not be practicable as the gunner would not be able to select the targets fast enough to catch up with the gun! An alternative was the StuH 42 10.5 cm howitzer to equip close support artillery units. H.L. Doyle’s drawing shows a small, one man, fully rotating turret armed with a 2 or 3 cm gun as an anti- aircraft/light vehicle weapon.
The suspension was to be externally mounted in a novel fashion. The swing arm contained the spring and damper mechanisms, moving against a fixed crank on the hull side. There were to be five units either side, each one supporting a single large road wheel. These were offset and overlapped in typical German style, so the track guide teeth ran between alternate wheels, with axles of the same length using spacers to give the correct offsets. The road wheels would have been 1000 mm diameter resilient steel type similar to, but larger than the 860 mm wheels for the late Panther G and the projected Panther F (not the 800 mm type from the Panther II or Tiger II). The springs inside the suspension housings were to be made from stacked Belleville washers with a central hydraulic damper. Each suspension unit was bolted to the hull side and bottom plate so it could be easily removed if damaged. The track was to be 66 cm wide the same as the Panther, but with only a single central guide tooth per link.
The hull armour was to be extremely well sloped, for instance the upper hull side plates were at 45 degrees. I believe the roof plate would have been bolted to the hull like previous German tank destroyers. I have concluded that the small roof turret would be offset to the left so that the gunner’s legs and body would not foul the breech area of the main gun. This would leave the driver with no exit from the vehicle as he would be blocked by the main gun to his right and the small turret behind. As a result I think there would be an access hatch located immediately above his position. This is on a sloping part of the roof so I doubt if it would be the lift and swing type from the Tiger II/E50/E75 so I have guessed on a simple side hinged pattern. Gun crew access would probably have to be in the rear right hand corner of the roof, and here I think it would have been a circular hatch design similar to that on the Jagdpanzer IV. It could have been simply cut out from the plate rather than from a new piece of metal. See Doyle’s article in last year’s Mil Mod for the same idea on the Schmalturn rear hatch.
The engine was originally meant to be an Argus air cooled motor mounted transversally at the rear, driving an eight speed gearbox with hydrostatic steering, but this was probably not to be fitted straight away as it was still under test. Also designated was a water cooled maybach engine of 400 HP, the extra 50 HP being lost through fans and pumps for the cooling system. The Spielberger book’s data tables show the liquid cooled Maybach HL 230 P30 as fitted to the Panther, but this was probably to be mounted only as a test engine, being in production for quite a while and well proven. The 700 HP available would have given the E-25 a speed of 65 kph. This amount of horse power coupled with the wide track would have made the E-25 extremely agile. 350 - 400 HP would still have given ample reserves of power. As there are no drawings available of the roof and engine deck these areas are pure conjecture. I based the master I made for Cromwell Models on a bit of guess work on airflow. Most air cooled engines are fitted with sheet metal cowls which fit fairly close to the cooling fins. The idea is to get the air as close to the cylinder as possible. Any fan is kept as close as possible to the cowls as otherwise there has to be ducting etc. For an instance, look at the SdKfz 234 (trop) armoured car series. They sported louvres on the engine deck but absolutely no sign of a fan. Luckily the Tank Museum has a Tatra engine on display and it shows the fan mounted directly on the end of the engine, well away from the decking and other external parts. Even with the low silhouette the E-25 would have had a usefully sized fighting compartment, due to the transmission position at the rear of the vehicle and the external suspension units. It would have had much more internal volume than the Hetzer. While I was building the model I kept placing it next to a Panther and a King Tiger to visualize its size and was constantly amazed at what a neat and effective design it was. Perhaps the only draw back would have been the length of the L/70 gun barrel. Stuck right at the front of the vehicle it would have been prone to damage in built up areas, and from nosing into the earth when on the rough. This was initially seen as a major drawback to the Jagdpanzer IV Lang but careful handling circumvented the problem.
The E-25 was to slot into place between the Panzer 38D, a wholly German, greatly simplified and enlarged development of the Czech Panzer 38(t) and the E- 50 Panther. Panzer IV chassis production was to be phased out completely as all the weapons it carried in its various guises could be taken by the 38(d) which was two thirds the weight and size. If E-25 had ever fought against Shermans and Cromwells it would have made an extremely difficult opponent to destroy.
Make no mistake, this was not a fantasy vehicle. Some hulls were completed by 23rd January 1945 and were at Kattowitz ready to be moved to a proving ground (Entwicklungskommission Panzer, Berlin W8, Pariser Conference Hall)
[LEFT]Thanks to Gordon Brown of Cromwell models for help and encouragement all the way through this project.
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Bibliography
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[li]Specialpanzerfahrzeuge des deutschen Heeres Spielberger. Motorbuchverlag.[/li][li]Sonderpanzer Feist. Aero Publications.[/li][/ul]http://fingolfen.tripod.com/eseries/e25.html