37 replies to this topic

[cwjian90]

Okinoshima, on Aug 15 2013 - 14:00, said:

especially IIRC the Renauld-Balland wasn't a conventional turret IIRC?

I believe you are correct on that assumption. Histoire de Guerre B&M describes it as a "pseudo-tourelle".

Okinoshima, on Aug 15 2013 - 14:00, said:

Speaking of turrets, Joseph Molinié mentioned a Char B with a three-man turret armed with a 75mm three man turret. IIRC this wouldn't be the Char B1 Ter right? A different design?

I doubt it is the B1 ter, as the B1 ter was going to retain a 75 mm gun in the hull, except now with limited traverse. Would have been redundant to have it with a 75 mm gun in the turret.

[Souroy]

The B1 Ter was to receive an uparmored (70mm) ARL 2C (the regular non-uparmored variant was planned to equip the S40 (the original version, not Vichy's improved one).
To illustrate: Prototype of the S40 with a mock-up of the ARL 2C / Drawing
Original ARL 2C armor (not counting the mantlets): 40/40/60 (thicker at the rear to serve as a counterweight (no easy joke, thanks))

What Joseph Molinié refers to is the 2nd version of the B40 which was studied in a hurry by ARL after the first AARs from the front arrived (basically "One man turret = bad").
Development continued during the occupation and became the ARL 44 after the liberation.


And I'm sorry for the compact aspect of my texts, I keep spotting various errors and each time I edit my posts to correct them the forum simply kill the line spacing.

[cwjian90]

Souroy, on a tangent here, but it is correct tos ay that the ARL 44 stock turret ingame is unhistorical, right?

[Blackhorse_Six_]

Great article, and great insight ...

Welcome Back, Souroy ...

(+1)

[Luissen]

I love my AMX 40, and now, thanks to you, I know even more about it :)

[Souroy]

cwjian90, on Aug 15 2013 - 18:50, said:

Souroy, on a tangent here, but it is correct tos ay that the ARL 44 stock turret ingame is unhistorical, right?

The "Barn" ?
Yes, there's no way the FCM F1's rear turret would have been used for the ARL 44, in 1944 the fortress tank concept has been dead and buried for a long time (hopefully, though I still find the idea of a multi-turreted land battleship pretty classy ), it's illogical (to stay polite) to have it magically reappear in the shape of the turret of the tank that's supposed to show the world that France can once again make tanks.

[Dominatus]

Do we have any idea what the original turret with the 76mm gun would have looked like? The same thing as the original prototype?

[cwjian90]

Could this have been it?

[Okinoshima]

Since they were both ARL projects, did the SARL 42 'become' the ARL 44? Any shared design lineage or were they completely seperate projects?

[Souroy]

Different designs with different results.

The true ancestor of the ARL 44 is the B40 heavy tank (more precisely ARL's version, afaik AMX didn't really made progress on theirs before the Armistice).
The SARL 42 project (cavalry tank, though it would be more correct to say medium tank as Vichy get rid of the infantry/cavalry separation in 1940) was ended with the invasion of the free zone which definitively destroyed all hopes of producing the tank.

But they were linked in some way, the head engineer of the B40, Lavirotte, was also the head engineer for the SARL 42 as well as part of the team (with a mention for Hubert Clermont, ex-engineer from ARL and subordinate of Lavirotte, he's credited with the design of the SARL 42 hull and his testimony is the main source of infos on the project).
Same for Lafargue's team which developed the gun of the SARL 42 (see previous page) and at the same time the gun of the 75mm armed B40 (with the possibility of mounting it on the SARL 42).
And also Devenne's team which worked on the ARL 42 turret (for the SARL 42) and on the B40.

In resume, for the SARL 42:
- General design and hull: Lavirotte's team, Paris
- Turret: Devenne's team, Caussade (free zone)
- Gun: Lafargue's team, Caussade (free zone)

And most engineers of these three teams had worked/were still working on the B40.

[Okinoshima]

By that you mean the 75 mm gun the B40 was armed with in it's chassis right?

[Souroy]

No, as explained previously the B40 project started in early 1940 (February IIRC) and was to become the replacement of the whole B1 family (B1, B1 Bis and B1 Ter), two companies were contracted with this study, ARL and AMX.
The original design comprised two guns, one high velocity 47mm (probably 47mm SA37 or 47mm Mle.1934 RF) in a two-man turret and one 105mm C in the hull.It's this version that is represented in this pic (more precisely, ARL's prototype which may be in the same wreck than the B1 Ter prototypes).
But the reports from the battlefields, where the B1 Bis, although a fearsome opponent, showed the limits of the multigunned design made the army change the specificities of the B40.
Thus the tank lost its 105mm and the turret became a three seater, with a 75mm instead of the 47mm.
After the defeat the development of this version continued clandestinely to finally become the ARL 44 in 1944 (or at least serve as its basis).
By the way, if someone is interested, I made few weeks ago a chronology of the ARL 44 development during a discussion with Slakrrrrrr:

Spoiler                     

Quote

I can't really tell about the design by itself (the whole 30t/60mm armor) but the original idea was indeed to use the 75mm SA44 (and not Long 44, don't know where the hell they saw this designation), then it changed for a mix between the 75mm SA44 and a 90mm, guns respectively made by the ACL and Schneider.
To simplify:
- 9 October 1944: The new tank should be realized quickly from existing components needing no others studies than their assembly (short: we need tanks asap).
- 25 November 1944: Order for 500 Transitional Tanks equipped with the 75mm SA44.
- 28 December 1944: Previous order reduced to 200 tanks, the 300 others should be equipped with a 90mm.
At this point the engineers already realized the shortcoming of the 75mm SA44, after all it was just a little bit more powerful than the 75mm M3 which was already completely outdated. By the end of 1944, engineer Lafargue imagined a new 75mm, firing the same round than the 75mm SA44 but at much higher velocity (1000 m/s against 715 m/s for the SA44), with a longer barrel (around 70 calibers long), etc etc...
The idea wasn't kept for the ARL 44 but we can easily understand that it foreshadowed the 75mm SA50 of the AMX 13.
At the same time Schneider had two possibilities, either make a 90mm from the 90mm CA Mle 1939 or start a totally new, and more powerful, gun (the idea was to be at least at the level of the 8.8cm KwK43, something that wasn't achievable when using the 90mm CA 39 as basis). The problem was the decisions of October 9th, if the choice of developping a new gun was made they would absolutely not make it in time.
Yet the EMGG (Etat-Major Général Guerre / General War HQ) gave their consent and so Schneider abandoned the adaptation of the 90mm CA 39 to work on the new 90mm (and thus the 90mm SA45 appeared).
- 17 January 1945: Order for 200 000 AP and 200 000 HE rounds for the 75mm SA44.
- Somewhere in early 45: 150 000 AP and 150 000 HE ordered for the 90mm.
- 23 June 1945: Only 50 75mm and 150 90mm version of the tank to be produced.
- 9 February~6 May 1946: 75mm program limited to only two turrets and 54 guns for experimentations and reduction of the 90mm version to only 60 vehicles.
- April~July 1947: First tests of the 90mm, severals problems on both chassis and turret.
- October 1947: Tests and end of the "75mm version" program.
- July 1948: The STA (Section Technique de l'Artillerie - Artillery technical service) receive a complete tank.
- July~September 1948 / July 1949 / September 1950: Tests.
- 21 September 1950: The EMFA/G (Etat-Major Général des Forces Armées / Guerre - what replaced the EMGG) declared, seeing the result of the tests, that the only modern part of the tank is the 90mm, which is of acceptable functioning. As such the STA propose the adoption of the Transitional Tank not as a 50t heavy tank but as a "protected and mobile antitank weapon".
- 26 October 1950: Adoption of the ARL-44 as a 48t Tank Destroyer.
- 20 December 1954: Decision is taken to retire the ARL-44 from service while keeping usable modern parts, mainly the guns which are send to the DEFA.
Source: COMHART Tome 9 - L'armement de gros calibre, pages 100 to 106.
So as you see can there is absolutely no mention of the 76mm M1 being mounted, or even thought, on the ARL-44.
But more details should be available in the 6th volume of this book series: Vehicules blindés et tactiques (Armored vehicles and tactics) which should contain countless infos, not only on the ARL-44 but also on most post-war vehicles, project, prototypes...
Unfortunately I've never found it.

[Okinoshima]

Sorry, a bunch of short questions:

So an order from 1944 for 500 'transitional tanks'. Just to clarify that would be the B40 in particular or was that more along the lines 'built 500 anything, we need tanks ASAP!'?

Would the 3 man turret on the B40 have been the ARL 42 turret planned for the SARL 42 or a different design?

What do we know about the ARL 44 prototype that was lost on the sunken ship?

Why didn't the EMGG just request a tank armed the American 76 mm M1? Wouldn't that have been easier to obtain quickly rather than having to design and set up production of an entirely new gun? Was it political reasons? Americans not interested in stretching their own supply of guns?

I've read multiple French sources lauding the 47 mm SA35 and SA37's (the SA39 from what I understand was just a standard, towed SA37 on a newly designed carriage) anti-armour capabilities (albeit by 1940 standards) but in-game their penetration is seen as rather lacklustre. Do you think WG extrapolated these guns in-game performance well with it's real life characteristics?

[Souroy]

Okinoshima, on Aug 16 2013 - 17:27, said:

Sorry, a bunch of short questions:

So an order from 1944 for 500 'transitional tanks'. Just to clarify that would be the B40 in particular or was that more along the lines 'built 500 anything, we need tanks ASAP!'?

Whatever they would manage to build, to reduce delay no prototype were planned and the commission specified that 50~70 tanks should be produced per month.
They lived in some sort of utopia...

Okinoshima, on Aug 16 2013 - 17:27, said:

Would the 3 man turret on the B40 have been the ARL 42 turret planned for the SARL 42 or a different design?

Probably another turret, no details available.

Okinoshima, on Aug 16 2013 - 17:27, said:

What do we know about the ARL 44 prototype that was lost on the sunken ship?

B40 prototype you mean, well no more than what the drawing show, so it lacked the armaments (including the turret) and the engine (but apparently the whole suspension/tracks were complete and working, the prototype was described by Stéphane Ferrard as rolling (so you could move it around as long there was something to tow it))

Okinoshima, on Aug 16 2013 - 17:27, said:

Why didn't the EMGG just request a tank armed the American 76 mm M1? Wouldn't that have been easier to obtain quickly rather than having to design and set up production of an entirely new gun? Was it political reasons? Americans not interested in stretching their own supply of guns?

Honestly, I can't really tell, if I can take a wild guess it would be a mix of lack of available 76mm (we're still in 1944~45, French armored units (2e DB for example) received relatively few 76mm Sherman compared to others units, some kind of national pride ("let's use a French gun") and maybe political reasons.

The last point appeared more clearly few years after with the beginning of the Indochina war where, in 1945/46, France was lacking of an efficient armored forces (anything was used due to the lack of anything better).
A logical thing would have been to send already formed armored units from France to Indochina but the equipment was weary from the fights in France and Germany and the USA were more than reticent to send spares which they knew would be used in what was a colonial war

Okinoshima, on Aug 16 2013 - 17:27, said:

I've read multiple French sources lauding the 47 mm SA35 and SA37's (the SA39 from what I understand was just a standard, towed SA37 on a newly designed carriage) anti-armour capabilities (albeit by 1940 standards) but in-game their penetration is seen as rather lacklustre. Do you think WG extrapolated these guns in-game performance well with it's real life characteristics?

The main differences between the 47mm SA37 and the 47mm SA39 are, as you said, a different carriage, and the addition of a flash hidder/muzzle brake.
To the contrary of the 25mm SA34/37 (the 25mm SA35 was the shortened variant of the SA34 mounted on armored cars/tanks, it used a more powerful ammo to compensate the shorter barrel) which were incredibly discreet when firing (courtesy of their flash hidder), the 47mm Mle.1937, when firing, let off a long flame which revealed the gun (plus the ammunition which had a magnesium cap which flashed when hitting the target, pretty nice to know if you hit or not but it also burned during the flight as a tracer, once again revealing the gun. Some crews had for habits of removing this cap).

About the performances of these guns, imo Wargaming don't do these guns justice (in some case it's just ridiculous).
To compare the numbers from France 1940, L'armement terrestre by Stéphane Ferrard with WG's values:
Note: the angle is from the vertical.

25mm SA34/35/37: 40mm/30° at 400m / 46~50mm/0° at 100m
37mm SA18: 15mm/30° at 400m / 29mm/0° at 100m
37mm SA38: 30mm/30° at 400m / 34mm/0° at 100m
47mm SA34: 25mm/30° at 400m / 25mm/0° at 100m
47mm SA35: 35mm/30° at 400m / 45mm/0° at 100m (David Lehmann give 40mm/30° at 400m)
47mm SA37: 106mm/0° at 100m / 66mm/0° at 100m

And I still don't understand why the Germans captured French tanks have more penetration than the same guns but on French tanks (Ger 37mm SA38: 41mm - Fra 37mm SA38: 34mm / Ger 47mm SA35: 55mm - Fra 47mm SA35: 45mm).
The guns of the Germans premiums seems in line with the historical values so why not the same on French tanks ?

Still from the discussion with Slakrrrrr (I let out the comparison with guns from others nations as it's not my domain and I don't want to offence anybody if I made a mistake):

Spoiler                     

Quote

Here's an attempt at making a hierarchy, from least to most powerful penetration-wise, taking in account tank guns (mounted or "could-have") and AT guns (including prototypes):

- 13.2mm Hotchkiss Mle.1930
- 37mm SA18
- 47mm Mle.1885 de marine
- 47mm SA34
- 37mm SA38
- 47mm Mle.1902 de marine
- 47mm SA35
- 75mm SA35 (same value at 400m (35~40mm/30°) than the 47mm SA35)
- 25mm Mle.1934 and Mle.1937 (and SA35 the shortened tank/armored car variant using a more powerful ammo to compensate)
- 65mm Mle.1902 de marine
- 75mm SA45 (Post-war gun planned for the modernization of the AMD 35 Panhard, originated during the study of the SARL 42 - V° 550m/s)
- 75mm Mle.1897 (with the Mle.1910M round, count ~25% better performance if using the Mle.1897/1940)
- 75mm APX L/30 and L/32 (L/30 =>SAu 40, ARL V 39 / L/32 => G1 project. Same differences Mle.1910M / Mle.1897/1940 than with the 75mm Mle.1897)
- 75mm SA49 (V° 600m/s)
- 29/20mm Larsen/APX (V°1400m/s)
- 37mm Mle.1934 RF
- 47mm Schneider (unfortunate rival of the 47mm Mle.1937 - V° 750m/s - 70mm/30° @ 400m)
- 47mm Mle.1937 and Mle.1939
- 47mm Mle.1934 RF
- 75mm Mle.1939 (L/40 - V° 700m/s)
- 75mm SA44 (Post war development of the 75mm Mle.1939 - V° 715 m/s)
- 90mm CA Mle.1939 shortened (for the FCM F1 and heavy AT gun project)
- 90mm CA Mle.1939
- 75mm SA50
- 90mm SA45
- 100mm SA47
- 120mm SA46

So it's not 100% accurate as you can't really classify guns of different calibers, designed for different uses, with their specific ammunitions and tested at different ranges/angle but it should give a rough idea.

[Okinoshima]

Souroy, on Aug 16 2013 - 22:55, said:

Whatever they would manage to build, to reduce delay no prototype were planned and the commission specified that 50~70 tanks should be produced per month.
They lived in some sort of utopia...

Doesn't sound too different from Germany in 1945! But anyway, I guess given how ridiculous the order was, official or not, the manufacturers had nothing in mind either?

Quote

Probably another turret, no details available.

That's definitely the biggest issue with the B40.

Quote

B40 prototype you mean, well no more than what the drawing show, so it lacked the armaments (including the turret) and the engine (but apparently the whole suspension/tracks were complete and working, the prototype was described by Stéphane Ferrard as rolling (so you could move it around as long there was something to tow it))

No I mean specifically the ARL 44 prototype. There are a couple of photos that I've seen to be of the ARL 44 prototype such as cwjian90's photo and this mock up

Quote

The main differences between the 47mm SA37 and the 47mm SA39 are, as you said, a different carriage, and the addition of a flash hidder/muzzle brake.
To the contrary of the 25mm SA34/37 (the 25mm SA35 was the shortened variant of the SA34 mounted on armored cars/tanks, it used a more powerful ammo to compensate the shorter barrel) which were incredibly discreet when firing (courtesy of their flash hidder), the 47mm Mle.1937, when firing, let off a long flame which revealed the gun (plus the ammunition which had a magnesium cap which flashed when hitting the target, pretty nice to know if you hit or not but it also burned during the flight as a tracer, once again revealing the gun. Some crews had for habits of removing this cap).

About the performances of these guns, imo Wargaming don't do these guns justice (in some case it's just ridiculous).
To compare the numbers from France 1940, L'armement terrestre by Stéphane Ferrard with WG's values:
Note: the angle is from the vertical.

25mm SA34/35/37: 40mm/30° at 400m / 46~50mm/0° at 100m
37mm SA18: 15mm/30° at 400m / 29mm/0° at 100m
37mm SA38: 30mm/30° at 400m / 34mm/0° at 100m
47mm SA34: 25mm/30° at 400m / 25mm/0° at 100m
47mm SA35: 35mm/30° at 400m / 45mm/0° at 100m (David Lehmann give 40mm/30° at 400m)
47mm SA37: 106mm/0° at 100m / 66mm/0° at 100m

Well in the SA39s case, just for comparison sake the British 2 pounder Mk IX and Mk X was a forged barrel, other than that the two guns in real life have the same penetration values but in WoT there is a huge different between the two...

Also thanks for the penetration numbers.

[Souroy]

Okinoshima, on Aug 17 2013 - 04:08, said:

Doesn't sound too different from Germany in 1945! But anyway, I guess given how ridiculous the order was, official or not, the manufacturers had nothing in mind either?

No, I would think they were too preoccupied with the state of their factories to think about developping new tanks on their own.
Schneider for example went from four top-notch ovens in 1940 to a single, basic, one in 1944. During the development of the 90mm SA45 they even had to stop working for some times in 1946 because it was unsafe and the results were simply awfuls (due to a lack of equipments (only one microscope...), lack of qualified personnel, poor steel...)

Okinoshima, on Aug 17 2013 - 04:08, said:

No I mean specifically the ARL 44 prototype. There are a couple of photos that I've seen to be of the ARL 44 prototype such as cwjian90's photo and this mock up

If by "on the sunken ship?" you refers to the Mécanicien Principal Carvin, there were no ARL 44 (prototype or not) on it for the simple reason that on 21 June 1940, day on which it was sunk, the ARL 44 didn't exist.

The mockup you're showing date from 1944~45 (or maybe even after as it's showing the ARL 44 in its final form, with Schneider turret and a 90mm SA45).
In cwjian90's photo, it would be the 75mm version with ACL's turret (ACL which was also the company who developped the 75mm SA44 equipping it (on the basis of the work done on the 75mm CA Mle.1928 during the occupation)).

[Okinoshima]

Sorry, I guess my mind sort of wandered while I was typing that.

What's the history of the ARL's original ACL turret? What were it's characteristics?

Were there any other sort of interim or immediate post-war French designs of interest that you haven't mentioned yet?

[Souroy]

I don't have any more infos on the ACL turret than what wikipedia has, my source focus on the guns.

And about other projects, nope can't see anything else than what people already knows (without going in the 6 bazillions of AMX M4/AMX 50 variants that never left the drawing board.)