Hello. Today I’d like to talk about French tier V premium tank, the SOMUA SM.
After doing many researches with my friend Surblind using what is in Colasix’s releases of Chatellerault archives, and in a single book mentioning it, we’ve come to a list of certain problems regarding this tank. Along with that, curing some of them may help in development and addition of future vehicles (AMX M4 TO100 and AMX 50 100), as well as fixing other tanks that use similar technical features (Lorraine 40t, Bat.-Chat. 25t, AMX 50 TO90/930, AMX 50 TOA100, AMX 50 Surbaisse, future AMX 50 120).
The material is finalized by me with @Surblind and @Surbass help, while @LeGrandSarrazin, @Colasix and Telegram channel @divtankistoria provided me with crucial sources and illustrations.
The full list of SOMUA SM’s troubles goes like this:
- UNREVIEWED
Wrong hull modelling and transmission position
The tank hull is wrong regarding the lack of machine gun in front and misplaced transmission. It seems Gaijin tried to make the model more accurate than Wargaming’s try, but they missed the MG port visible on front photograph of SM. The misplacement of transmission is more difficult to prove, but there are key factors such as light going through the holes in tracks on both photographs, which would be impossible if the sprocket was in the rear (whose “teeth” would block the light, contrary to what we can see in-game), and transmission ventilation pipes being seen on the hull roof in the front. If you take a look at documents and blueprints, it is mentioned to be in front, and from the top you can see a hatch on the hull roof front, to which the crew hatches are also attached, meant for easier transmission ejection and replacement during service.
The tank is also possibly higher in the game than in real life judging by the blueprints, due to wrong torsion bar angle (the hull bottom plate must align by height with the roadwheels by their center rather than by their 1/4 from the top).
I covered the mistake regarding rear armor plate not being split in two in the next issue.
All SOMUA SM errors, part 1: visual and internal model
Reconstruction of more realistic SOMUA SM by Divannaya Tank. Istoriya Telegram
Original blueprint featuring general layout of the tank (the turret is analogue TOA120)
Front photo of SOMUA SM where you can see the machine gun left to the headlight,
transmission ventilation pipes on the hull roof, and light going through holes in the
rear of the tank meant for sprocket teeth to go through
Wrong armor modelling
Armor values, their angles, and modelling are incorrect in most spots. The armor is the most wrong thing Gaijin has done to the SM. They probably have copied hull armor from World of Tanks, where is it also around 150mm or such in the front. In real life, the armor there is much lighter, however, lower front plate, sides and rear armor are slightly reinforced compared to in-game. Blueprints also demonstrate that the armor angles in the game are slightly off. Gaijin also hasn’t split the rear armor plate in two, as visible on blueprints, and, difficult but still possible, on the tank rear’s photo.
Have a little table explaining hull armor:
Front, UFP by angle / LFP by angle: 75mm by 58deg / 75mm by 50deg
Side, USP by angle / MSP by angle / LFP by angle: 50mm by 24deg / 20 mm horizontal / 40mm flat
Rear, URP by angle / LRP by angle: 50mm by 23deg / 40mm by 52deg
The hull bottom armor can’t be viewed normally, but judging by the fact that 39mm HE penetration shell cannot blow the tank up by hitting roadwheels just below the hull but the 49mm pen shell can, it might be around 40-45mm. In real life it’s just 30mm. Hull roof remains the same at 20mm.
All SOMUA SM errors, part 2: armor model
Blueprint featuring front and bottom hull armor
Blueprint featuring rear hull armor
Blueprint featuring side and roof hull armor
Rear photo of SOMUA SM where you can hardly see the separation of rear plate into two,
right where the hinges start (which are present in the blueprints but aren’t present in the
game either). The light also goes through the holes in the tracks here, signalizing there
are no sprocket teeth to fit them.
Too little gun breech
In comparison to other tanks that use 100mm SA47 gun (Lorraine 40t and AMX 50), SOMUA SM has significantly smaller breech model and hitbox. That means damaging breech of SOMUA SM is unjustifiably harder than doing so to AMX 50 and Lorraine 40t.
Inconsistent gun breach size - Somua SM 100mm SA47 L/58
SOMUA SM’s gun breech is smaller for no reason, in fact even the parts of the loading
mechanism are a part of breech hitbox on Lorraine 40t and AMX 50, meaning easier penetration and destruction of it on mentioned tanks
Wrong TO100 turret and collar armor
New report regarding the armor of TO100 turret and collar, using blueprints. Right now, the front armor is limited at 120mm turret front, above and below, 60 lower front cheek, sides, 40mm rear, 30mm cupola (which can be penetrated frontally even by early IFVs and APCs), and 120mm all-around collar.
In reality, armor is much lighter on the front, being 70mm on upper part, and ranging from 105 to 125mm on lower part (bottom to connection with upper plate). Sides are generally 60mm, except for hinges which are 170-180mm depending on area hit, being little strong-spots (contrary to big weakspot being the whole side. Rear is also 60mm, but walls for the ejector door area (which is improperly modelled) are 30mm, the ejector door itself is also ranging from 20 to 30mm, but on the left it has a strong-spot at 110mm thick. The weird lines on the rear of the turret are 130mm deep into the turret, thus are strong-spots too. Commander cupola nominal armor is at least 46mm in weak areas (rear, center of the turret) and is mostly around 77-120mm (front, turret side end), giving actually great LOS numbers compared to current 40-60mm, given the angle.
The collar must be varied as mentioned in the next report below, around 175mm front, 200mm sides (below) and 125mm rear. Hinges above the 200mm area, however, are only 50mm thick (and are still a strong spot, considering the 180mm of armor deep behind them).
SOMUA SM’s TO100 turret wrong armor
Blueprints, featuring front, side, rear, cupola and collar armor, which varies greatly
compared to in-game
SOMUA SM’s turret armor more realistic fan-made example, if fixed and published in-game
- ACCEPTED
Incorrect turret model
TO100 has incorrect collar armor, lacks two shells in first stage ammo rack, lacks two machine guns on the roof, and the ejection door for casings is too little. Recently the collar armor has been buffed from 40mm to 120mm all around, however, it must be modelled within variable thickness, having around those 120-150mm in front, around 30-40mm in 1/3 direction, and around 150-200mm in sides and rear. It is visible on the game model viewing it from the top. Blueprints feature 9 shells included in first stage ammo rack instead of just 8, plus 1 spare shell in the turret rear. The casing ejection door is too small, it is a bit smaller than gun caliber in fact and must be greatly increased in size. The TO100 turret also lacks dual machine guns on top, which were installed around loader’s hatch (same problem is with the other tanks who have FAMH-manufactured turrets, TO90 and TOA100. AMX 50 Surbaisse has the similar problem with the absence of 20mm MG 151).
Somua SM | AMX 50/100 incorrect turret model- TO 100
Thickness of the collar armor varies in each area, even visually, however, in the game it
has a static armor thickness
Not just the ejector door is smaller than the gun caliber, it is meant to throw out not the
100mm wide projectiles, but ~140mm empty charges with rings on their base, making
them even wider than that
The first-stage ammo rack holder (the drum) appears to be modelled in the form of a
round, instead of being oval, and holds just 8 shells instead of 9. The spare shells
quantity in the turret rear must be decreased to 1, and become the part of first-stage
ammo rack, as mentioned in the loading mechanism report
The in-game tanks with TO100, TOA100 and TOB120 turrets got none of their IRL anti-air
machine guns and autocannons
Incorrect implementation of loading mechanism
The way game mechanics work, the tank must receive mechanically assisted loading with first-stage ammo rack system rather than an autoloader, making tank still able to fire once it’s empty, but with a slower speed. In real life, you could fire mechanically assisted shot every 4 seconds using the armor-piercing ammo, 9 in the drum and 1 in the turret rear (first-stage ammo rack), and fire a high-explosive shot taken from the turret rear and below the loader, every 6 seconds. In the game, we can fire all 8 (must be 10… see further) shots with 4 seconds interval, and then the tank must hide in cover, instead of being able to fire again, just slower due to the drum being empty, but the ammo racks still present around the loader, who is able to put the shells onto the rammer’s cart, which would then ram them into the breech, completing the reload.
The same mechanic applies to the TO90/930 turret, and probably to the rest of 90mm/100mm FAMH turrets, but there is no documentation on their part.
Наличие механики АЗ. Somua SM, Char 25t, AMX 50 (TO90/930) (in Russian)
AMX 50 100 manual explaining the principle of reloading the gun
- MISFIXED
Wrong gearing, lack of neutral steering
Gaijin has fairly recently “fixed” SOMUA SM by giving it 50km/h speed instead of 40km/h, on it’s last gear… fourth gear, despite reports always clearly stating that the maximum speed of 50km/h was reached on fifth gear. The tank also lacks neutral steering, despite using the system similar to that of ARL 44. A newer report was made to point out the mistake done before and finally put a period regarding SOMUA SM’s gearing problem.
SOMUA SM incorrect transmission and lacking neutral steering
A letter mentioning that SM could reach it’s maximum speed of 50km/h on 5th gear,
unlike 4th in the game, the latter causing massive torque loss.
A letter mentioning the presence of neutral steering on SM tank, currently not in-game.
- MISCELLANEOUS
(Minor) The tank manufacturer spelling
SOMUA stands for Société d’outillage mécanique et d’usinage d’artillerie. Being an abbreviature, it must be spelled in all capital letters. The other SOMUA tank, the S.35, has no such mistake if you point at it in the tech tree.
Société d'outillage mécanique et d'usinage d'artillerie — Wikipédia
Theories on the tank weight and classification
Currently, we have no sources to cover the real mass of the tank, but we theorized that it is much lighter than it is in the game. Making volume measurement of the tank’s armor and metal parts and mathematically adding up the density of armored steel, and then adding the known mass of TO100 turret, Maybach HL295 engine and slightly reduced mass of Tiger II transmission (not identical but constructionally similar to that of SOMUA SM’s), we get around 48-50 tons. Makes sense, as the tank overall has less armor, and less complicated suspension system than that of AMX 50 100, which weighs 53 tons. We are still waiting for primary sources to come and prove this information.
In the meantime, it is worth mentioning that even the AMX 50 Surbaisse with it’s 58.7 ton mass was considered a "char moyen of the 50-ton tank program, the “medium tank”, the same program SOMUA SM belonged to. Thus, with it’s battle mass being less than that of AMX 50 100, the SOMUA SM is to be re-classified as a medium tank in-game.
False accusation from bug report manager, explained
A bug report manager has accused me of using blueprints that “feature different prototype, the one not shown in the game”, giving me “not a bug”. They ignored the fact that in-game model has so many visual errors (MG port, sprocket location, rear plate and hinges there) and thus can’t even be considered to be one “in-game”, and on the contrary had said that real photos do not have such features on the tank such as MG port and transmission in front (no worries, being blind is okay). In fact, multiple official letters clearly state that only one prototype of SOMUA SM has been made. It is mentioned in a book “Les vehicules blindes francais 1945-1977” by Pierre Touzin. The one shown on photos and the one depicted in blueprints, letters and modern reconstructions is the only one that ever existed, and Gaijin has got it wrong.
SOMUA SM — неверная толщина бронирования корпуса (in Russian)
The letter, mentioning that first there was an order for two SM vehicles, but in the end,
just one was requested with some spare sparts
A cut out from the aforementioned book, where it copies the officials’ letter text
@Surblind had told me a joke that Gaijin could make an entirely new and historically realistic SOMUA SM based on our research, while removing this abomination with 150mm armor from the tech tree view and Gaijin Store, and making it available only to those people who already own it. Who knows, every truth has a bit of joke in it…
