tanks/vehicles Panzer IV Ausf. G/H mit Hydrostatischem Antrieb (Hydrostatic Drive)

[Results45 2,200]

Hello, today I am suggesting a peculiar-looking tank -- the Panzer IV Ausf. G/H with Hydrostatic Drive:

 

Short History

 

The Panzer IV Ausf. G/H mit Hydrostatischem Antrieb was the result of an alternative drive system developed for the Panzer IV.  Hydrostatischem Antrieb (German for hydrostatic drive), nicknamed the "Thoma" drive, was designed, built, and tested in 1943 on a repaired Panzer IV Ausf. G chassis recovered from combat.

 

Surviving Panzerkampfwagen IV mit Hydrostatischen Antrieb in the US. Note the now sloped engine deck, and the smaller rear drive wheels. (Source:- commons.wikimedia.org)

 

 

The Thoma drive operates similarly to the petrol-electric drive found in the Porsche Tiger 1 prototype and the Ferdinand "Elefant" tank destroyer, but had the added benefit of being less prone to catching on fire.

 

The Hydrostatic Drive system outside of the vehicle. Photo: – Spielberger Publishing

 

The Panzer IV chassis used for testing underwent heavy alteration in order to mount the new drive system. The engine compartment was almost completely rebuilt and housed the drive under a large sloping engine deck.  Behind the drive, two supporting oil pumps were installed and connected directly to an unmodified Maybach HL120 TRM engine powering two hydraulic motors. A swash plate drive sent power through a reduction gear into the newly added rear drive wheels, which replaced the original idler wheel.

 

The new controls added to the Panzer, note the new control “wheel” and the many new dials. Photo: – Spielberger Publishing

 

In 1944, the vehicle was tested with a hydraulically-powered Panzer IV Ausf. H turret.  One working prototype powered by the new "Thoma" Hydrostatic Drive was ever built only to be captured by the US 3rd Infantry Division advancing through Augsburg on April 28th, 1945.

 

 

A year after WWII ended, the vehicle was shipped back to the United States where it was analyzed and tested in Detroit, Miscigan by Vickers Inc. on April 12th 1946. This was the resulting report filed:

 

“The power train consisted of two staggered-plate oils pumps that are assembled as a unit and are driven by a 12-cylinder Maybach engine. Oil is pushed by the pumps to two separate oils engines which power the drive wheels of the tracks. The oil engines are attached to the final drive housings. The engine and power aggregate are located in the rear of the vehicle, and the vehicle is moved by rear mounted drive wheels. The volume of the pumps is controlled by the driver, who thereby controls the torque of the various pressure conditions that are created by the steering and stopping of the vehicle. In the same manner, the forward and backward movement of the vehicle is achieved by directing oil flow. Pressurized oil to activate the pumps and engines and for the high-pressure connections was advanced by a geared-wheel pump that was connected to the vehicle’s engine by direct drive.”

 

 

Most if not all German test data was lost and the vehicle was left to the elements at the Aberdeen Proving Grounds in Maryland. It was relocated in 2015 to the US Army Center for Military History Storage Facility in Anniston, Alabama where it now officially rests.

 

This Pz.Kpfw IV mit hydrostatischen antrieb is now in storage in the U.S. Army Center for Military History Storage Facility, Anniston, AL, USA. (Photo – Masa Narita)

 

Source: http://www.tanks-encyclopedia.com/ww2/nazi-germany/panzer-iv-mit-hydrostatischem-antrieb/

 

 

Alternate article from Achtungpanzer.com: 

Spoiler

Panzerkampfwagen IV mit hydrostatischen Antrieb.

Sonderausführung des PzKpfw IV.

 

Sonderausführung des PzKpfw IV.

In late 1943, Zahnradfabrik Augsburg equipped normal (turretless) Panzerkampfwagen IV Ausf G/Hwith newly developed hydraulic steering system. Thoma (non-liquid) oil drive transmission was installed and drive sprocket was replaced with the new one. The power train consisted of twin oil pumps driven by Maybach HL 120 TRM engine. In order to accommodate all the changes, entire engine deck and rear was modified. In mid 1944, this prototype was fitted with modified hydraulically operated turret. Tests were carried on but were never concluded and for testing purposes the only prototype was send to Russia and served with the Waffen SS unit. At the end of the war, this vehicle was captured by the US Army and was sent to United States for further examination. Tests were never concluded and this vehicle is still at Aberdeen U.S Army Proving Grounds in Maryland.

 

Sonderausführung des PzKpfw IV.

 

Panzerkampfwagen IV mit hydrostatischen Antrieb at Aberdeen. 
Photo provided by Alec Corapinski.

http://www.achtungpanzer.com/10-5cm-k18-auf-panzer-selbstfahrlafette-iva-dickermax.htm

 

 

Specifications:

Designation                                                    Panzer IV mit Hydrostatischem Antrieb
Dimensions	5.41 x 2.88 x 2.68 m (17.7×9.4×8.8 ft)
Total weight, battle ready	25 tons
Crew	5
Armament	Rheinmetall 75 mm (2.95 in) KwK 40 2-3 MG 34/MG 42 7.92 mm (0.31 in) machine-guns
Armor	From 15 to 65 mm (0.59-2.56 in)
Propulsion	Maybach V12 gasoline HL 120 TRM (220 kW) 300 bhp@2500 rpm
Suspension	Leaf springs
Speed on /off road	42 km/h (26 mph)
Total production	1

 

 

Additional Images:

Spoiler

 

 

Additional Links and Resources:

Spoiler

Links & Resources

• The Panzer IV on Wikipedia
• The Panzerkampfwagen IV on Achtungpanzer
• Panzer-IV und seine Varianten (Panzer IV and its Variants) Spielberger and Doyle.
• Panzer Tracts No. 4, Panzerkampfwagen IV, Grosstraktor to Panzerbefehlswagen IV
• Panzer Tracts No. 4-3, Panzerkampfwagen IV Ausf. H and Ausf. J, 1943 to 1945

 

 

Hope you like it! 

Edited May 14, 2018 by Results45

[blakeob 8,086]

Open for discussion. 

[Results45 2,200]

Finally.  

[Baka_9_Cirno 55]

I think with the amount of panzer ivs we already have now it's not that wise to add even more panzer ivs.

 

That one thing aside, it's good to have. Any info for the rear armour?

[Results45 2,200]

13 hours ago, Baka_9_Cirno said:

I think with the amount of panzer ivs we already have now it's not that wise to add even more panzer ivs.

 

That one thing aside, it's good to have. Any info for the rear armour?

 

Should be same as the Ausf.G frontally and along most of the sides.

 

Turret is practically identical to the Ausf.H of course. 

Edited April 17, 2017 by Results45

[CaID 8,996]

1 hour ago, Baka_9_Cirno said:

I think with the amount of panzer ivs we already have now it's not that wise to add even more panzer ivs.

 

That one thing aside, it's good to have. Any info for the rear armour?

there is also too much sherman. let kick them out of the US/UK/JP tree. also we should do the same with the T-34.

 

There is tanks dynasty. the Panzer Dynasty is very important and we should be please to see so many variant. that one is very special. it look like a regular panzer with a diaper. i love it.

[seadogpirate@psn 888]

I think this should be in the general tree or the panzer 4 bfw moved too the general tree and this put in it's place.

[GoneToTheAether 9,581]

This would make a good premium or event thing I think. 

 

Was it any more or less maneueverable than the normal Panzer IV H?

[Admiral_Aruon 2,264]

+1

 

i'd like to see this in the research tree, it's different enough that its worth adding but not so different that it's needs to be a premium as the better armored panzerbefehlswagen IV is already there.

 

5 hours ago, MH4UAstragon said:

Was it any more or less maneuverable than the normal Panzer IV H?

 

it's meant to be far more maneuverable while not needing to switch between gears. it can go from stop to max speed quickly through direction of pressurized oil, and with its hydrostatic drive it can turn on all but a dime without significant loss of speed.

 

here's a description of a hydrostatic drive:

 

Hydrostatic drives are widely recognized as an excellent means of power transmission when variable output speed is required. Typically outperforming mechanical and electrical variable-speed drives and gear-type transmissions, they offer fast response, maintain precise speed under varying loads, and allow infinitely variable speed control from zero to maximum.

 

Unlike gear transmissions, hydrostatics have a continuous power curve without peaks and valleys, and they can increase available torque without shifting gears. But despite the superior performance of hydrostatics, a major drawback has been higher cost compared to their mechanical counterparts.

 

in a nutshell it's everything related to maneuverability that the panzer 4s have always lacked. all in an efficient engine that is basically fireproof.

Edited April 17, 2017 by admiral_aruon

[Retry 7,363]

Quote

The Thoma drive operates similarly to the petrol-electric drive found in the Porsche Tiger 1 prototype and the Ferdinand "Elefant" tank destroyer, but had the added benefit of being less prone to catching on fire.

So basically this thing is a Pz.IV with Ferdinand/FerdiTiger reverse speeds?

[Results45 2,200]

30 minutes ago, Retry said:

So basically this thing is a Pz.IV with Ferdinand/FerdiTiger reverse speeds?

 

Not really sure what its exact reverse speed was, but being lighter than the Tiger 1 and Ferdinand it would definitely accelerate backwards faster.

[Admiral_Aruon 2,264]

1 hour ago, Results45 said:

 

Not really sure what its exact reverse speed was, but being lighter than the Tiger 1 and Ferdinand it would definitely accelerate backwards faster.

 

it would hit probably max reverse speed about as fast as the terrain (and that gut punch torque) would allow. with a hydrostatic drive there's no gear shift as its basically automatic.

[The_Doctor_084 1,583]

Bring it in as event or premium.

[CVB_Zuikaku 469]

I like the Hybrid tanks in the game, Be nice to have more. 

[Ryan_King 907]

Gib +1

[War_Embodied 107]

mmmm, that panzer T H I C C

 

But I would love to have a tank like this, as I love these strange one off and experimentals

[HMSD33Dauntless 1,257]

+1, I'm curious to see how its drive would be modeled in game regarding gear shifting too. If it has a fast reverse speed I definitely want it, I like a tank with a good reverse speed. It might work well at 5.0 actually if it has better mobility and reverse.

Edited May 13, 2017 by HMSD33Dauntless

[Nuclear_Frog 363]

There is already a suggestion with 65 votes. I have tried to raise it up a few times too.

 

https://forum.warthunder.com/index.php?/topic/240255-panzer-iv-with-hydrostatic-transmission/&

 

[Results45 2,200]

8 minutes ago, Nuclear_Frog said:

There is already a suggestion with 65 votes. I have tried to raise it up a few times too.

 

https://forum.warthunder.com/index.php?/topic/240255-panzer-iv-with-hydrostatic-transmission/&

 

 

Nice.

 

IMO mine's better though (better post and poll questions)  

[Dalles 56]

Up



+1

[pieve 3,578]

+1

 

[FORMATOSE 901]

I would like just to add this :

 

The removal of the front-mounted SSG 77 mechanical transmission and its torque shaft allowed to shift the centre of gravity rearward (improving its balance) and freeing space.
A hydrostatic transmission allow highly precise steering with an infinitely variable turn radii and also to perform a neutral steer (pivot turn in place).
Modern Western main battle tanks use hydrostatic transmissions as standard.

 

[Results45 2,200]

3 hours ago, Auto_tracking said:

I would like just to add this :

 

The removal of the front-mounted SSG 77 mechanical transmission and its torque shaft allowed to shift the centre of gravity rearward (improving its balance) and freeing space.
A hydrostatic transmission allow highly precise steering with an infinitely variable turn radii and also to perform a neutral steer (pivot turn in place).
Modern Western main battle tanks use hydrostatic transmissions as standard.

 

 

Thanks for finding that diagram!  

[Mercedes4321 4,695]

21 hours ago, Results45 said:

 

Nice.

 

IMO mine's better though (better post and poll questions)  

Well your poll is still missing some potential options, such as no option for it to be added to the regular tree.

[Results45 2,200]

5 hours ago, Mercedes4321 said:

Well your poll is still missing some potential options, such as no option for it to be added to the regular tree.

 

Only one was ever built....... should it be it be in the stock tree?