Entwicklungsfahrzeug series

[robunos]

"The Entwicklungsfahrzeug series program was conceived by Oberbaurat Kniepkamp in May 1942
and authorized as a project in April 1943..."
I'm looking for more information on this series of experimental/developmental panzers.
There was to have been the E-10, primarily a test-bed, but to be developed into an
operational vehicle, the E-25, similar to the 'Hetzer', the E-50/75, derived from the Panther,
and the E-100, a super heavy tank, proposed as an alternative to the 'Maus' project.
Among the snippets I can find are the following images...
(sources, first one, 'Panther and it's variants', Spielberger, page 156,
second one, 'German Secret Panzer Projects', Waldemar Trojca, page 85)

cheers,
Robin.

 

[sagallacci]

The E-100's intended turret was not simply an original version Maus turret. That came out of an errornious reconstruction of drawings at the end of the war.
Jentz and Doyle's Panzer Tracks No.6-3 has a history of the E-100 and drawings of a proposed turret.
Speilberger and Doyle's Special Panzer Variants has a chapter on the E-program, including drawings of the E-25, including details of the suspension system, drawings of the E-50 and E-75 hulls, and a lot of photos of the E-100, but included the incorrect turret drawing.

 

[robunos]

Thanks for that,
I've seen a drawing of the E-100 with a different turret, but I can't place
it just at the moment.
I also have a drawing of the E-50, but I'm unsure as to whether to post it,
because of possible copyright problems.. The same reference also has drawings
of the the proposed suspension for the E-50, the one using conical washer
(belleville) springs.
I'm also looking to dis-ambiguate the E-50/75 designs.


cheers,
Robin.

 

[sagallacci]

From the Speilberger & Doyle book, the difference between the E-50 and E-75 is thicker nose armor, slightly longer, and closer spaced road wheel pairs with an extra pair to deal with the extra weight. The drawings include key dimensions.
Do you mean the Speilberger Panther book? It has the good drawings of the E-50 suspension system. Note that the turret with the 88/L70 is fictional, Jentz and Doyle debunked that later.

 

[robunos]

Thanks for the clarification on the E-50 and E-75.
Unfortunately, funds are somewhat scarce at the moment,
so new books are going to have to wait awhile. :'(
The E-50 drawings I have are from the Spielberger Panther
book, the side view has "copyright H.L.Doyle '76" on it,
which is why I didn't post it.


cheers,
Robin.

 

[kampfflieger]

Another E-series one, scout tank based on E-10 with Leopard turret.

BTW - does anybody know what is E-5?

 

[Nik]

I'm curious about the road-gear-- small vs large, and overlapped.

IIRC, one of the otherwise excellent late production designs was bollixed by overlapped road-wheels as, to repair an inner, they had to remove both adjacent outers plus, possibly, another if access was tight...

Uh, the large road-wheels seems to contribute an unfortunately tall profile. Was this a trade-off for enhanced obstacle crossing ??

 

[kampfflieger]

This is not big tank, so it's only looking high. In fact it's short

 

[kampfflieger]

E-series panzerjagers and jagdpanzers;

 

[moin1900]

Re: Entwicklungsfahrzeug E-5

Hi everybody

Some infos about the E-5 Wanze mini tanks
http://www.achtungpanzer.com/entwicklung-series-standard-series.htm

Text about the E-5 series.
From Waffen und Geheimwaffen des deutschen Heeres 1933-1945by Fritz Hahn
http://www.whq-forum.de/invisionboard/index.php?showtopic=15415

Maresal Tank
http://en.wikipedia.org/wiki/Mare%C5%9Fal_tank_destroyer

Rutscher
http://en.valka.cz/viewtopic.php/t/40022
http://strangevehicles.greyfalcon.us/rutscher.htm

Wanze with recoilless 10,5cm gun
http://www.achtungpanzer.com/mittlere-ladungstrager-springer-sdkfz304.htm

Borgward Wanze
http://www.achtungpanzer.com/wanze-borgward-b-iv-ausfuhrung-mit-raketenpanzerbuchse-54.htm
http://www.achtungpanzer.com/gepanzerte-munitionsschlepper-vk302.htm

Very interesting PDF ! With drawing !
KLEIN PANZER armed with two MG42 and one cannon.
http://www.servicehistorique.sga.defense.gouv.fr/
http://www.servicehistorique.sga.defense.gouv.fr/02fonds-collections/banquedocuments/materiel_armement/notice_armement/liste_blinde.php
and
http://books.google.com
search Lummitsch Klein-Panzer

Many greetings

 

[kampfflieger]

Thanks a lot, very interesting!

 

[robunos]

Thought I'd posted this before, must rememer to click the 'post' button....

Uh, the large road-wheels seems to contribute an unfortunately tall profile. Was this a trade-off for enhanced obstacle crossing ??

Nik, the idea was that the E-Series would use as many common parts as possible, to ease production and supply difficulties, due to enemy action, and also, I would have thought, to facilitate field repairs. Thus all the E-Series vehicles were to use the same type of wheels, in this case the resilient steel Tiger II wheel.
The Leopard/E-10, and I believe the E-25, also had a depressible suspension system,to enable the vehicle to go 'hull-down', and reduce it's silhouette. If you look at the Leopard/E-10 drawing, you'll see the large gap between the top run of the track and the underside of the track guard. This is to allow the hull to be lowered.

EDIT - Here's a quick and dirty edit job to show my idea of the Leopard/E-10 in 'hull-down' mode.


cheers,
Robin.

 

[lastdingo]

I dunno the English words for them, but the small wheels are that high for a reason.

The forward one is that high in order to enable the climbing over obstacles.
The back end one is that high because it's the one that transfers the mechanical power to the track. It could be lowered (somewhat), but only at the cost of a much worse power efficiency factor because the mechanical power would need to be transferred through two additional joints.

 

[itzhak]

Hello. First post on the forums, been lurking around for a while and have really enjoyed the huge amount for knowledge there.

Does anyone have any more info on the E-75 tanks other then what is available on achtungpanzer/wikipedia? I'm looking for a some details about its armor layout.

 

[robunos]

Re. my post above, #11, I have this very day received a copy of 'Panzer Tracts' 20-1; Paper Panzers.
It confirms the variable-height suspension :-
"The E-10 was unique in having an auxiliary engine coupled to the suspension in order to raise and lower the vehicle." page 20-20.
It also confirms that the E-25 did not have this feature.

Lastdingo. it's the roadwheels that move up and down, not the small wheels.they are fixed to the hull at the front and rear.
[in English, the one that transmits the power is the 'drive sprocket', or just 'sprocket'. The other one is the 'idler'.]
In the case of the E-10, it would move to a concealed firing position and lower itself down. It would then wait in ambush for enemy AFVs.
During this time it would not move. Indeed, when lowered down, the bottom of the hull would be resting on the ground, so the E-10
_couldn't_ move.


cheers,
Robin.

 

[robunos]

Note that the turret with the 88/L70 is fictional, Jentz and Doyle debunked that later.

Can you enlighten us further on this, as there are drawings of this, both the turret itself, and the turret mounted
on a Panther hull, in ''Panzer Tracts' 20-1'.


cheers,
Robin.

 

[sagallacci]

Don't have the newer Panzertracks. My comment was more regarding the Panther narrow turret fitted with the 88 for the PantherII, PantherF and, presumably the E-50. Now, if the E-50 had a larger turret ring, I'd guess the 88 could be fitted.

 

[robunos]

Sorry, Sagallaci, didn't make myself clear.
What I meant to say was, where, as in what book, etc., did Jentz and Doyle announce that the turret with the 88mm L/70 was fictional?


cheers,
Robin.

 

[carsinamerica]

I know that the Achtung Panzer site mentions it, but is there credible sourcing for the Krokodil E-100 tank destroyer? If so, what was its intended specification? Or are the Krokodil and Alligator simply speculation?

 

[Grey Havoc]

http://www.friendsreunited.com/partially-built-panzerkampfwagen-e-100-heavy-tank/Memory/bea00d9e-d196-4ed8-a585-a04e0090f251

 

[Foo Fighter]

Entwicklung E-25.

I have been looking around the internet for quite some time, for information on this almost mythical machine. Some things can be relatively easily worked out because the guns for example were those available 'off the shelf' rather like a high st suit. Other things are not so easily ascertained. The engine for example is apparently the Tatra 103 diesel V12 but the drive was apparently intended to be from the rear of the vehicle. The consensus of opinion is that the gearbox would have been a standard ZF AK 7-200 or ZF AK 7-150 but the 7-200 which was fitted to the Panther was a longitudinal mounted unit. Given that and the rather large engine, how on earth would this have worked? I have looked at this so many times I daren't say but I cannot see a method where these items would fit into an E-25 hull considering the locations of the crew access points in the images I have found. I am looking for engine and gearbox data all the time but find nothing new. Some folk want to believe torsion bars would have been used while think that standard wheels from the Panther etc would have been used as an interim solution rather than the oversized items suggested, ie 1000mm rather than 660mm.
Anyone have anything to add?

 

[poky]

a lot of things about the E-25 is fictional simple because what is known is not that much, the MG turret is not a WW2 design but added by a model company, but the engine and suspension are known, the torsion bar or 860mm wheels are not based on evidence at all, there where more then 1 option for the engine, HL100 and in March 1945 HL101 was selected, couple of others where mentioned in the design fase as well. ZF was working on the gearbox but none where selected

 

[Foo Fighter]

Thank you. I have been taking most of my information from Panzer Tracts. From discussion with MR HL Doyle my thoughts about cancellation were more or less confirmed. Too little in the way of information about drivetrain being confirmed to take any other conclusion. What exactly the hulls that were rumoured to have been sent to Alkett in Berlin-Spandau were supposed to achieve I do not know. If the drivetrain had been fitted perhaps some data could have been acquired but otherwise, not much point. Did the Germans HAVE a transverse gearbox is what I am trying to ascertain right now, a transverse engine installation perhaps but even that is problematic.

Apparently there were actual hulls with drivetrain of the Jagdpanzer 38-D and this was a much more realistic project.

Thanks for the reply.

 

[Foo Fighter]

No idea if this is known or not. http://tankarchives.blogspot.co.uk/2016/05/medium-paper-tank-destoyers.html

 

[Foo Fighter]

As happens when researching such topics, things have turned 90 degree's on me. In order to get SOME kind of logical item at the end of the tunnel. There is talk of the Maybach HL 100/101 perpendicular to the transmission but given the HL 101 is apparently putting out 550bhp I cannot see the result free's up space while complicating the drive method. I can see the engine being above the gearbox but 90 degrees to it makes no sense packaging wise. Does anyone have a link I might use to get enough data to create an HL 100/101 in 3d CAD? Dimensions? I would greatly appreciate any pointers, thank you.

 

[Michel Van]

The Biggest problem for Information on E-25
it was one of last tanks projects of WW2

even at Argus Factory in Karlsruhe, were they undecidedly what to use as Gun
the remaining technical drawings show a 7,5-cm-Panzerjägerkanone 42 L/70

on MG turret same thing, they no idea what to use or for what
one proposal was Anti aircraft gun in dome Turret with one 30-mm-MK 108 autocannon

The Reason is simple its 1944/45, it lack on everything
Materials, petrol, guns & Ammunitions, personel
here you take what you get and build it into tank with what you got
Next to that were last minute change of Orders, special if this coming from "Little Annoying Austrian" in his bunker in Berlin.
like install bigger guns into tanks as planed...

interesting note
as Allies visit the Argus Factory after War
there were no E-25 parts to be found.

 

[Foo Fighter]

I understand and agree on all points, what I am trying to do is find a way the components of the time 'could' be utilised to create a facsimile of the E-25. There is a suggestion that the engine could have been a HL 100/101 but I cannot find any information on these engines apart from the speculation that they might have been used. There is also a suggestion that the engine cpould have been mounted perpendicular or 90 degrees from the transmission. The transmission could have been the ZF 7-200 from the Panther. In order to have something in 3d I have reduced the elements to a HL-100/101 mounted directly above the transmission which will be a ZF 7-200 as this makes more sense to me than the 90 degree mounting as that is where the space is. Any diagrams available would help with this but I understand folk may be against this. The information just does not appear to be on the internet.

 

[Foo Fighter]

I have acquired some new historic information based on British reports from interviews. Not got all the info in yet but will be back when I do. I have a layout from a German magazine circa 1964 here. The transverse engine layout is clear and the hydraulic transmission also. From the little I have read the transmission/steering is almost exactly the same as the TOG-1 variety and has a lag of approximately 1 second in the system. Unfinished hulls? Sounds like not.

 

[JFC Fuller]

Thats the Porsche 245/2, a design in the same class but not the official E-25 as designed by Argus.

The entire German AFV programme at the end of the war seems to have been driven by the ambition to make what they already made cheaper. The E-Series seem to have been a long way from production (a long way from complete prototypes even) and I cant see much evidence of any real attempt to develop superior main guns to the 75mm KwK-42 and 88mm KwK-43.

 

[Foo Fighter]

Understood, not finished the documents yet and those I have point to a difference between designs at different times and the change in doctrine. I am trying to find a way to enhance the contrast and will post more as I get to it. I was actually looking for information on different Maybach engines in order to recreate these in CAD form. What I have read so far includes details of transmission and steering but this is all happenstance from contacting the tank museum about Maybach information.

 

[sgeorges4]

Something on the E-50-75 serie:
http://ftr-wot.blogspot.com/2013/04/e-50-weserhutte.html
http://tankarchives.blogspot.com/2017/04/e-50-and-e-75-story-of-failed.html
https://forum.warthunder.com/index.php?/topic/394373-replace-the-panther-ii-and-105mm-tiger-ii-with-e-50-and-e-75/
https://forum.warthunder.com/index.php?/topic/388089-entwicklungserie/&page=5

 

[GWrecks]

Another E-series one, scout tank based on E-10 with Leopard turret.

BTW - does anybody know what is E-5?

1. How did they intend to keep that in the 10-ton range? The Leopard was nearly 22 tons.

2. Multiple sources suggest an E-5 was never actually proposed. For example, the drawing I think of regarding a proposed E-5 had six roadwheels when the E-10 had only four. That seems to imply it would be larger (The roadwheels were shared between models), despite being half the weight of an E-10. And having fewer roadwheels (Two?) would make it look like something out of a comic strip. Highly unlikely.

 

[Michel Van]

1. How did they intend to keep that in the 10-ton range? The Leopard was nearly 22 tons.

2. Multiple sources suggest an E-5 was never actually proposed. For example, the drawing I think of regarding a proposed E-5 had six roadwheels when the E-10 had only four. That seems to imply it would be larger (The roadwheels were shared between models), despite being half the weight of an E-10. And having fewer roadwheels (Two?) would make it look like something out of a comic strip. Highly unlikely.

On E-10 it was Light tank design in 10-25 tonnes weight,

On E-5 was a supposed to be 5-10 tonnes in weight, more of fast reconnaissance vehicle and armored personnel carriers or battlefield tractor
some sources claim the E-5 was never part of Entwicklungsfahrzeug series

 

[poky]

A guy named Fritz Hahn wrote a book waffen und geheimwaffen he is the first to make the claim that the E-5 was a real thing, only wrote a couple of lines about it where he mostly talks about the Borgward with 6 panzerschreks which is of course not the E-5, the book is full off mistakes and other then the V-2 parts which he worked on its not worth getting.
The Rutcher part of the panzerkleinzerstorer project also claimed by some to be the E-5, started by achtungpanzer.com
So far there are no original documents that name the E-5.
I think the E-5 got misunderstood for panzerkleinzerstorer project as this is around the same time, similar weight and role

 

[Foo Fighter]

I get the impression that there were many re-designations and adjustment of role etc. It seems that very little was set in stone but changed over time.

 

[JFC Fuller]

I have no idea how accurate the content of this link is, and I am reliant on the google translation to understand its content, but if it is accurate it gives a level of detail on the E-50/75 that I have not seen before. I took away the following points (that I may have misunderstood):

Hull: The armour plates used the same angles as the E100, so the tank would have looked like a scaled E100 with a (newly designed) turret mounted forward, ahead of the rear mounted transmission, steering system and engine.

Transmission: A single integrated unit would have included the two final drives, the gearbox and steering mechanism, all inside the rear hull and behind the engine. This arrangement saved 1 ton of weight and reduced manufacturing hours by 25%. The E-50 was to have a top speed of 60kmh versus 40kmh for the E-75, the gearboxes would be identical with the change being achieved by replacing a single gear on each side.

Suspension: The well known Adler designed external suspension.

Engine: Maybach HL232, this used turbocharger powered by a 2 cylinder auxiliary engine that also served as a starter motor, it also used direct fuel injection instead of the carburettors used on the HL230. It was liquid cooled. Continuous power rating was 1,000hp but 1200hp could be achieved for short periods at 3200rpm. This was still in testing but the fuel injected HL234 was available in prototype form.

Turret: Krupp was designing the turrets, the E-50 and E-75 would have identical turret rings and both would use electric traverse, the weapons would be different though. [JFC speculation; they probably would have been similar to the Panther Aus F Schmalturm but designed round a wider turret ring and with a turret bustle for ready rounds, giving the appearance of a flat-topped (Henschel) Tiger II turret (also designed by Krupp).

The blog has lots of interesting articles, e.g. this one about the PulsGetriebe PP33 designed for the Tiger II.

 

[DiePanzerKanone]

I have no idea how accurate the content of this link is, and I am reliant on the google translation to understand its content, but if it is accurate it gives a level of detail on the E-50/75 that I have not seen before. I took away the following points (that I may have misunderstood):

Hull: The armour plates used the same angles as the E100, so the tank would have looked like a scaled E100 with a (newly designed) turret mounted forward, ahead of the rear mounted transmission, steering system and engine.

Transmission: A single integrated unit would have included the two final drives, the gearbox and steering mechanism, all inside the rear hull and behind the engine. This arrangement saved 1 ton of weight and reduced manufacturing hours by 25%. The E-50 was to have a top speed of 60kmh versus 40kmh for the E-75, the gearboxes would be identical with the change being achieved by replacing a single gear on each side.

Suspension: The well known Adler designed external suspension.

Engine: Maybach HL232, this used turbocharger powered by a 2 cylinder auxiliary engine that also served as a starter motor, it also used direct fuel injection instead of the carburettors used on the HL230. It was liquid cooled. Continuous power rating was 1,000hp but 1200hp could be achieved for short periods at 3200rpm. This was still in testing but the fuel injected HL234 was available in prototype form.

Turret: Krupp was designing the turrets, the E-50 and E-75 would have identical turret rings and both would use electric traverse, the weapons would be different though. [JFC speculation; they probably would have been similar to the Panther Aus F Schmalturm but designed round a wider turret ring and with a turret bustle for ready rounds, giving the appearance of a flat-topped (Henschel) Tiger II turret (also designed by Krupp).

The blog has lots of interesting articles, e.g. this one about the PulsGetriebe PP33 designed for the Tiger II.

I think you misunderstood the part about the hull: it says the hulls of the E-50 and E-75 are the same, not to the E-100
The article looks pretty accurate to me comparing it to info found in Panzer Tracts and other books - it is a nice compilation of all the E series tanks but missing the E-5.

 

[uk 75]

M39 doesnt have much in common with HS30

M39 armored utility vehicle - Wikipedia

en.m.wikipedia.org

The light tank was a Henschel proposal which was never adopted.

 

[DiePanzerKanone]

I don't think the RU 251 was based on the HS.30 chassis, compare the suspension

 

[JFC Fuller]

I think you misunderstood the part about the hull: it says the hulls of the E-50 and E-75 are the same, not to the E-100
The article looks pretty accurate to me comparing it to info found in Panzer Tracts and other books - it is a nice compilation of all the E series tanks but missing the E-5.

Sorry, I wasn't saying that the E-50/75 was to use the same hull as the E-100, just that the E-100 armour plates would have the same angles as those on the E-100, the English translations states in relation to E-50/75:

4. Housing . The angles of inclination of the armor plates were taken from the E-100 project. The upper frontal part is 30 °, the lower frontal part is 45 °, the upper aft part is 45 °, the lower aft part is 45 °, the upper part of the side plates above the chassis is 45 °.

Though I would caution that those angles don't match the available E-100 armour layout diagrams.

I have also realised that the diagrams showing the suspension layout also give some very useful measurements beyond those required to understand the suspension itself, notably the length and height of the hull as defined by the welded together armoured plates (excluding towing hooks, fenders, tracks, exhausts etc.). Based on this, the standardised E-50-75 hull is scaled to a very similar size to that of the Tiger II:

Hull height for the E-series at the rear is 1870mm versus 1860mm for the Tiger II.
Hull length for E-series, whilst not very precise due to pixel counting, comes out at 7000mm or a bit over versus about 6930mm for the Tiger II.

All of this combined gives us a good idea of how the E-50/75 may have appeared had it been built as conceived at the point at which the war ended. A Tiger II sized hull with the armour plates angled as on the E-100 design, external suspension with 6 road wheels on either side for the E-50 and 8 for the E-75. That just leaves the turret and gun, no other suitable weapon seems to have been in development and their was plenty of working space inside the vehicle (potentially more than the Tiger II), it therefore seems logical that the 88mm KwK 43 L/71 would have been the initial choice, probably with a similar or larger ammunition load out than the Tiger II.