Char B40

By the early part of the 1940s, it was clear that the French Char B1 heavy tank, even in its B1 ter form, was not a long term design. The B1 had provided the Imperial French army with a heavy tank which had a very impressive level of armor at the time of its introduction, evolving over the course of its service from 40 mm to 70 mm, with a design which was sufficient large as to be able to easily bridge anti-tank trenches, a 75 mm gun which could knock out enemy fortified positions, and a 47 mm gun which served as a quite good anti-tank weapon. Unfortunately, it also brought along a very lengthy list of problems. The tank was hideously expensive, it required very careful maintenance, it was sometimes difficult to use the 47 mm and the 75 mm at once, the crew was overworked, and most importantly there was simply no real capacity to upgrade it. The combination of the turret and the 75mm gun in the hull meant that neither could be significantly improved, even if the B1 ter did provide a slightly larger turret ring, capable of accommodating a two-man turret. A need for a replacement for the heavy breakthrough role was evident. This meant the need to turn to the legacy of the Char B1, and what would replace it. The hull-mounted and turret-mounted weapon was clearly inefficient, as the attempt to deploy the vehicle into the fighting during the Indochina Emergency displayed - although to be fair, the catastrophic performance of the 7e demi brigade de chars de bataille had displayed was more due to the excessive weight and logistics requirements of the vehicle, and the inherent nature of Indochinese fighting, than any particular weapon it carried. But the Section technique des blindés was most concerned with the reports of difficulties with the armament and its effective utilization, stemming from the awkward set up of the multiple weapons and the poor available sights. A new, single weapon would be better served to replace it. But would it be the turret or the hull mounted gun which would be kept? A turret-mounted gun would enable the tank to be more flexible in mobile warfare, but at the cost of a higher profile, greater expense, and a smaller weapon. It was decided that given the main intended usage of the tank - break through of fortified enemy positions - that a high velocity hull-mounted gun capable of piercing enemy armor, destroying pillboxes, and shooting a highly potent high explosive round would be used. This was after the rejection of the alternate approach, a 155 mm low-velocity howitzer, which would instead be placed in special variants of the tank for specialized attacks in the most heavily fortified sectors. Thus was born, the B40, one of the world's most unique heavy tanks. It forms part of a variety of tanks in the French army, constituting a heavy assault tank designed to both break through enemy positions and engage enemy tanks, while self-propelled guns (the Somua SAu 40 being the medium-based self propelled gun, and the B40 A, a 155 mm version of the B40 would provide both indirect fire and direct assaults on enemy pillboxes and other positions which even the B40 could not destroy. Medium tanks (Previously the Somua 35, with the Char G1 replacing it currently) would form the main combat units for engaging enemy units and providing infantry support - essentially forming the principal mobile war branch of the army. Light tanks are in something of a flux, moving from previously heavily armored designs to faster and more heavily armed vehicles (thus the H40 bis and the AMC 41 exist simultaneously), so it makes classifying their usage hard as different formations use wildly different light tank types. And armored cars (Panhard 178, Panhard 178 bis, and AM 40P) would provide reconnaissance, covering forces, and very much functioning the way light tanks would in other armies. Tank destroyers were still not an entirely clear role in the French army, and so far the French army had not procured any, although in many ways its B40 heavy tank was essentially one. As a note, while the B40 is referred here as a heavy tank, it is actually not classified as that by the French army, which refers to it as a battle tank. Heavy tanks are actually superheavy tanks by the standards of other nations, and their design should be discussed elsewhere.The DCRs positioned for surveillance on the continuing bloodshed to the East from our less.... agreeable neighbors, are not recognized as heavy tank divisions by the French army, even if in the international context they de facto receive that appellation. But even the army of the French Empire lacks for the funds to build super heavy tank divisions, so there will probably never be a division heavier than that of the DCR. Description The Char B40 continues to be a large vehicle like its B1 predecessor, since it must be able to traverse enemy anti-tank ditches, and also since it also has to accommodate its engine, fighting compartment, gun, and thick armor. This gives it a total length of 6,5 meters (not including the gun length). It has a width of 3 meters, while its height is 2,4 meters. It looks quite boxy, with a sloping front, nearly vertical sides (they slope inwards slightly), and an engine deck which is reduced below the frontal fighting compartment, the latter jutting above the former like a frontal box. Typically they are painted in green French camouflage schemes with the insignia of their unit on the side, as well as the name of the tank (every French tank crew gives their tank a name), but they can of course receive different camouflage by region. Indicator lights facing to the rear are fitted for night driving so that it can be seen. Armament The Canon de 105 L mle 1936 Schneider SB (sous blindage) constitutes the principal armament of the vehicle. This is a modification of the Canon de 105 L mle 1936 Schneider, which is normally a corps-level artillery piece, firing a 15 kilogram shell at 725 meters per second. On the Char B40, it is semi-automatic with a modified breech, sights provided, and and with some other small changes to enable it to fit into the vehicle. The rounds that it fires consists of both high explosive, and armor-piercing rounds. It carries 60 rounds of ammunition, which is typically a mixture of high explosive and armor piercing, with the balance weighted towards high explosive. The gun can be depressed down to 7 degrees, and elevated to 20 degrees, and it has a traverse of 10 degrees. 6 rounds of ammunition are stored in a ready rack next to the gun for the loader. The remainder is stacked in its cases. Both general magnification and precise magnification sights exist for the gunner, which helps him in general scanning and then actually engaging the targets, as well as for the commander handing sighted targets off to him. Secondary armament consists of a 7,5mm coaxial Reibel machine gun (with a thicker barrel and different magazines, drum magazines, compared to the standard infantry light machine gun, permitting a greater sustained rate of fire), equipped with 2.400 rounds. There is also a 13,2 mm machine gun mounted on top of the cupola, which is designed to be utilized against enemy aircraft if the vehicle is under attack, but which if necessary can be used against ground targets, although with the risk of substantial exposure on the part of the the commander who utilizes it. It has 600 rounds available. The crew has two MAS-38 submachine guns for close range defense if need be. There are several firing ports for these small arms positioned on the side of the vehicle. Armor and Protection Given that the intent of the vehicle is to be a heavy tank, to break through enemy positions, it naturally is equipped with a very substantial amount of armor. Frontally, the vehicle is protected by 120 mm armor, sloped at 20 degrees from vertical, while the sides are 100 mm and the rear at 60 mm. The floor is protected with 30 mm of armor while armor protection covers the side track links, while the roof has 30 mm. The components are cast, and then welded together. The gun is protected with a substantial mantlet. There are track links carried on the front of the tank which provide some additional protection. Meanwhile, the side tracks with their running gear are protected by armor covers, which also gives the benefit of spaced armor, much increasing protection against enemy shaped charge attacks. If built to certain standards, the B40 can be rendered gas proof, although how easily this will be achieved in practice is up for question... There is an automatic fire extinguisher for the engine, and the crew have an escape hatch under the tank if need be. The tank is separated into two compartments, with the forward fighting compartment and rear engine, fuel, and transmission compartment, and the two are separated by a firewall. Mobility As a heavy tank, the B 40 is not designed as a fast vehicle. Still, just like the B1 before it, it is reasonably mobile, in this case thanks to a electrically started 500 horsepower petrol engine, which for the 40 ton mass of the tank makes it reasonably speedy, with a 12.5 horsepower per ton mobility. Its exhaust pipes are slanted to the side which means that infantry can shelter behind it in the attack without being poisoned. Hatches at the back can be opened for routine maintenance in accessing the transmission. A rear panel is also positioned there, which can be unbolted to enable the transmission as a whole to be accessed. Meanwhile, the top of the engine deck has a hatch to access the engine. This engine's power is directed by an improved Naeder (hydraulic) transmission system, which is essentially the same as that of the Char B1 - the principal improvement over previous tanks in the series is how much cheaper it is due to the allowance for a less precise system without the pinpoint accuracy required for a gun without any traverse (just like on the Char B1 ter). The same can be said concerning the gearbox, which was strengthened to deal with the increased weight. There are 5 forward gears, and 1 reverse gear, while the size of the road wheels grew so that there are "only" 10 per side. Track width is 550 mm (giving better ground pressure than previous vehicles) and is low running in contrast to the previous Char B series, based on vertical coil spring suspension. It projects slightly in front of the tank, giving it a good obstacle climbing capacity. Track tension is adjusted at the front. The transmission is mounted at the rear, which prevents the need for a gear-shaft to run under the crew, keeping the height relatively low. Internally contained ball bearings instead of constant daily greasing help to reduce maintenance struggles. A capacity of 600 liters in self-sealing fuel tanks provides, in part due to the changed transmission system and hull traverse, a range of up to 300 kilometers - plentifully sufficient. Its top speed is 35 kilometers per hour. Tow hooks on the back enable recovery. Crew, Communication, and Miscellenous There is a 5 man crew, which consists of a commander, driver, gunner, loader and radio operator/mechanic/assistant loader. They enter from a large swinging hatch mounted on the side, which is 100 mm like the rest of the tank's side armor. This hatch swings outward, and thus is also useful in that if one exits under fire, it provides a substantial degree of protection on the forward plane. It also means that it is easy to bring in ammunition into the interior. However, the commander also has a cupola which opens up and which is large enough for him to be able to get in and out of it, and thus this represents another exit/entry point for the crew : the gunner has his own entry/exit hatch, as does the driver. The commander has his seat at his cupola so he can place his head into it and look around with its episcopes and vision slits The driver is to forward left of the gun, the commander to the right, the gunner to the left, the loader behind it to the left, and the radio operator/mechanic/assistant loader to the right. All have seats. There are internal ventilators, and internal lights (which along with the variety of other electric devices are powered by an onboard battery, which can be charged by the engine.) As a note, French tank crews wear helmets, so they are less vulnerable to internal concussions from being shaken about. The driver is equipped with a forward vision block and periscopes, meaning that the gunner, commander, and driver can all see out, helping in providing vision to see the enemy first. There are also headlights for the driver for night driving. An internal intercom is fitted. The radio operator has a voice radio, capable of around 20 kilometers of range. Signal flags are carried for back up purposes. Stablock Weight: 40 metric tons Length: 6,5 meters (sans gun) Width: 3 meters Height: 2,4 meters Crew: 5 Commander Driver Gunner Loader Radio Operator/Assistant Loader/Mechanic Armor profile: Front: 120 mm /30° Upper sides: 100 mm /10° Lower sides: 100 mm /0° + track covering armor Hull rear: 60 mm /0° Top: 30 mm/90° Bottom: 30 mm/90° Engine: 600 horsepower petrol engine Max speed: 35 kilometers per hour on the road Transmission: 5 forward, 1 reverse gears 1st gear : 2.5 kms 2nd gear : 9 kms 3rd gear : 13 kms 4th gear : 22 kms 5th gear : 35 kms Autonomy: 600 l of fuel for 300 kilomers Armament: x1 105 mm / 37.6 rifled canon with 60 rounds of explosive and armor piercing ammunition, traverse of 10 degrees and depression/elevation of -7° and +20 x1 7,5mm coaxial Reibel machine gun with 2.400 rounds x1 pintle-mounted 13.2 mm anti-aircraft machine guns with 600 rounds x2 internally carried MAS-38 sub-machine guns capable of being fired from inside the vehicle Sights: Gunner: x1 panoramic sight x1 telescoping sight Commander: General sights: x1 panoramic sight Cupola: x1 periscopic sight x1 episcope x1 estienne sight Driver: x1 periscope vision slits All crew are also equipped with the Mk. 1 eyeball for when looking out hatches or cupolas.