France, 1921-1925, Experimental infantry tank – 1 prototype
The B1 and B1 Bis heavy infantry tanks are some of the most famous and popular of all pre-war French tank designs. Those particularly well-armored vehicles, with their dual configuration featuring a turreted 47 mm anti-tank gun and a hull-mounted 75 mm infantry support gun, and sporting tracks going around all of the hull in a fashion reminiscent of WW1-era rhomboid British tanks with massive individual track links, are some of the most peculiar mass-produced tanks of the late 1930s. Despite their serial production only really starting in the second half of the 1930s, the B1 and its improved version, the B1 bis, have roots going back as far as 1921, with the Char de Bataille program. One of the prototypes of this program which had some influence on the final B1 was produced by the company FAMH (Compagnie des Forges et Aciéries de la Marine et d’Homécourt – Company of Marine Forges and Steelworks and of Homécourt), better known under the name of the city where their main facilities were located, Saint-Chamond.
Estienne and the Char de Bataille
Arguably, the most important figure of the first years of French tank development was general Jean Estienne. Nicknamed the “Father of Tanks” (père des chars) in France, Estienne, a major proponent of the use of armored vehicles from 1915 onward, was named the director of the AS (Artillerie Spéciale – Special Artillery), the French armored force, in September of 1916. It is largely thanks to his intervention to the Grand Quartier Général, France’s general headquarters, that the FT light tank reached mass production. Estienne had also been a proponent of the Schneider CA1, the first French tank to see service.
On the other hand, the Saint-Chamond tank, which entered in service soon after the Schneider, was not at all appreciated by Estienne, though 400 would still be manufactured as the père des chars’s control onto tank production was still incomplete by 1915-1916.
At the end of the war, Estienne continued in his role as the leading figure of French armored development. He was still at the head of the AS, which was attached to the French infantry and renamed the Subdivision des chars de combat (Combat tank subdivision), and was also named Inspecteur des chars de combat (Combat Tank Inspector). In this position, Estienne had large amounts of power over the future development of French armored technology. With the French military having large quantities of largely effective light tanks thanks to the mass production of the Renault FT, and with the development of large tank already underway at FCM since 1916 with the FCM 1 and then FCM 2C super-heavy tanks, what the French military lacked in his view was an intermediate vehicle between the dwarves and the giants: a “Char de Bataille” (battle tank), thought of as a vehicle of medium weight, that would feature a fixed 75 mm gun able to engage enemy fortifications and positions, and to move through the devastated terrain typical of trench warfare in an artillery-saturated battlefield. Estienne thought the type would offer the ideal compromise, mounting an armament sufficient to knock out enemy fortifications and trenches, something the FT’s armament of either a machine gun or a 37 mm gun struggled with, while being vastly more reasonable and easier to mass-produce than a monster the size and weight of the 69-tons, 10-meters long Char 2C. If successful, the Char de Bataille would have eventually become the workhorse of France’s armored force.
The Char de Bataille program and the Estienne agreements
In 1921, Estienne gathered five of the largest French industrial companies in France: Schneider, Renault, FAMH/Saint-Chamond, FCM and Delaunay-Belleville, and gave them the requirements of the Char de Bataille which he requested them to design. The vehicle was to have a weight of 13-tons, and feature a hull-mounted main gun – either a 75 mm howitzer with a muzzle velocity of 350 m/s, or the higher velocity 47 mm mle 1902 naval gun, with 750 m/s muzzle velocity. The tank was to sport a turret armed with either one or two machine guns. It was to have a power-to-weight ratio of at least 8 hp per ton, and be able to run for 8 to 10 hours. The armor was to be 25 mm thick.
Most importantly, the program was not planned to result in the immediate adoption of the product that answered to the specifications the most. The plan was that, once the prototypes were produced, the most interesting features from each would be taken to then be adapted to a new tank design that would not be the property of a company, but of the state. The objective of such a move was to reduce competition and encourage the manufacturers to innovate without the risk of a yet not entirely mastered concept leading to the refusal of a proposal. Once the vehicle that combined the best features of each proposal was adopted, each of the manufacturers involved would play a part in the production. This original policy was named the Estienne agreements.
The FAMH vehicle: Smooth drive
In the end, four manufacturers would produce new designs for the Char de Bataille program. Delaunay-Belleville offered a previous design of theirs, an enlarged FT with a 37 mm hull gun and a turret, that had little to do with the program’s requirements and was swiftly thrown out of the equation. Schneider and Renault cooperated to produce two joint prototypes of different designs, while Saint-Chamond and FCM produced their own prototypes individually.
The FAMH design was the one that looked the most different from the other three in terms of general shape. While the FCM and the two Schneider-Renault prototypes were generally long, quite narrow and low vehicles, the FAMH was shorter and a lot bulkier, though it technically was not the highest due to the FCM’s high cupola reaching higher than even the FAMH’s turret The Char de Bataille FAMH had a length of 5.20 m, making it the shortest of the four proposed designs, a width of 2.43 m (which did not make it the widest vehicle, though the two wider ones, the Schneider-Renault, were this way because of their tracks and suspension), and a height of 2.40 m. The ground clearance was 0.45 m.
Unlike the three other prototypes, which had tracks pretty much going all around the hull, the FAMH vehicle had a much lower suspension, with the hull reaching out on top of it, unlike the other designs in which the hull was as wide at the top as at the bottom. This hull used riveted construction. The armament of the prototype consisted of a centrally mounted 75 mm howitzer, designed by Saint-Chamond (the industrial also being a prolific artillery manufacturer) and featured in a casemate, the only vehicle using such a configuration. The FAMH Char de Bataille also featured a turret designed by FAMH, which used riveted construction as the hull, and was armed with two Hotchkiss modèle 1914 8 mm Lebel machine guns. This turret’s functions were mostly to serve as a command post, and for close defense of the vehicle, with the commander serving in the turret, while the two other crewmen took place in the hull, which featured the vehicle’s main armament, the 75 mm howitzer. The FAMH is also reported to have been able to be armed with a hull machine gun, but this is not apparent on the prototype, and it is unknown from where this weapon would have been firing from.
As with the other Char de Bataille, the FAMH featured armor skirts protecting the suspension. The exact design which was used for the suspension remains unknown. What is known about it, is that it used six pneumatic systems, each weighing 55 kg, and damping springs. The pneumatic controls are known to have made the vehicle require a lot less physical effort from the driver, unlike other vehicles of the program. The track used wooden pads, as on the FCM and Schneider-Renault A prototype. The pitch was also considerable.
Trials – Estienne’s horse
FAMH’s Char de Bataille was trialed along with the three other vehicles in Rueil, starting with their presentation on 13th May 1924.
The Char de Bataille FAMH was powered by a Panhard engine producing 120 hp at 1500 rpm. This was the same engine as on the FCM, however, the FAMH weighed in at 17,000 kg, whereas the FCM had a weight of just 15,640 kg. This made the FAMH the vehicle with the lowest power-to-weight ratio of the four, with 7 hp/ton – 1 hp/ton under the requirements of 8. The vehicle could reach a maximum speed of 18.2 km/h, which actually appears to have made it the fastest of the Char de Bataille, by 0.2 km/h in comparison to the Schneider-Renault B. However, a domain in which the difference between the FAMH and the other vehicles was notable, and not in a good way for Saint-Chamond’s vehicle, was range. With the smallest fuel tank of all designs, at only 230 l, and a medium hourly consumption of 30 liters, the FAMH had a range of only about 75 km, the second-worst. The Schneider-Renault B had a whole 50 km more, with 125 km. Out of the three vehicles of which we know the trench-crossing capacity, the FAMH also had the shortest one, being able to cross a 2-meters wide gap, a consequence of the shorter suspension which did not fully go around the vehicle’s hull. At the same time though, the pneumatic drive of the FAMH considerably reduced the physical efforts of the driver and was quite appreciated.
The vehicle’s armament had both issues and advantages. The central mounting of the 75 mm gun proved mediocre for the driver, as it took a considerable amount of space, and made his position quite cramped. At the same time, the central casemate mounting was praised by Estienne. It was judged as perfectly placed, both in axis and height, to fire through the embrasures of enemy fortifications, where a successful shot would inflict the most damage. In general, out of all the Char de Bataille proposals, the FAMH appeared to be Estienne’s favorite.
Conclusion – The rejected favorite
The FAMH prototype was trialed along with the three others Char de Batailles from May 1924 to March of 1925. Its trials underlined some interesting features, mostly regarding the pneumatic controls.
The FAMH prototype was not the least influential when it came to the development of what would become the B1. Its pneumatic controls and damping springs ended up being featured on the much less obscure heavy tank, giving it some quite light controls for such a heavy machine. The Saint-Chamond 75 mm gun was also retained for the first two prototypes of the B1, though the third vehicle as well as the serial-produced B1 and B1 Bis would not end up using a FAMH 75 mm howitzer.
Nonetheless, the influence of Saint-Chamond’s designs remains fairly limited. For a vehicle that was dubbed Estienne’s favorite, the FAMH Char de Bataille is indeed overshadowed by the two Schneider-Renault prototypes, which laid the basis for the final architecture of the heavy infantry tank, as well as its complex Naeder hydraulic direction system. The fate of the FAMH prototype, arguably the most unique looking of the four Char de Bataille, is unknown, though ending up scrapped appears to be, by far, the most probable theory.
Char de Bataille FAMH specifications
|Dimensions (L x w x h)||5.20×2.43x.2.40 m|
|Engine||Panhard producing 120 hp at 1500 rpm|
|Maximum speed||18.2 km/h|
|power-to-weight ratio in hp/ton||7|
|Fuel tanks||230 litres|
|Average hourly fuel consumption||30 litres|
|Crew||3 men (Commander/turret gunner, driver/gunner, loader)|
|Armament||2 turret-mounted Hotchkiss mle 1914 8 mm machine gun, 1 hull-mounted 75 mm howitzer, perhaps 1 hull-mounted Hotchkiss mle 1914 8 mm machine gun|
|Armor||25 mm maximum|
Tous les blindés de l’Armée Française 1914-1940, François Vauvillier, Histoire & Collection editions, p 42-43
GBM N°107 (January-February-March 2014), Histoire & Collections editions, “Les voies difficultueuses du char de bataille”, p 45-46, Stéphane Ferrard
Trackstory N°3 : Les chars B, Editions du Barbotin, p 5-7
Tank Archives: http://www.tankarchives.ca/2016/12/char-b-difficult-beginning.html
Ateliers de Construction de Rueil – Services des Etudes – Char B1 Bis – Notice sur la description et l’entretien des matériels