Char D1

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Char D1
General characteristics
Crew	3
Length	5.76 m
Width	2.16 m
Height	2.40 m
Weight	14 metric tons
Armour and armament
Armour	40 mm
Main armament	47 mm SA34 tank gun
Secondary armament	2x 7.5 Reibel MG
Mobility
Power plant	Renault V-4 74 hp
Suspension	vertical springs
Road speed	18.6 km/h
Power/weight	?
Range	90

The Char D1 was a pre-World War II French tank.

The French plan of 1926 to create a Light Infantry Support Tank led to the change of the existing Renault NC1 prototype into the Char D1. The type was produced between 1931 and 1935 in a number of 160. There was a pre-series of ten vehicles; later 150 standard vehicles were built. Until 1936 the vehicles were fitted with FT-17 turrets because the intended cast ST2 turrets weren't ready yet. The ST2 turret was armed with the short 47mm SA34 tank gun with a coaxial 7.5mm MG. The hull carried a 7.5mm MG in the bow. The type didn't serve as an infantry support tank, but as France's major battle tank of the early thirties; it was quickly phased out in 1937 because of its unreliability.

[edit] Development

After World War I, France possessed a very large fleet of FT-17 light infantry support tanks. Although many of these were sold to other nations, over 2800 remained. In contrast to the United Kingdom, that strongly reduced its armoured forces and scrapped any redundant AFVs, France maintained a large number of active or mobilisable armoured units (with an organic strength of about 1260) and all remaining FT-17s were kept in working order. This implied that in the early twenties France had the strongest and most modern armoured force in the world, but this very fact led to a state of complacency: tank development was not seen as urgent, also because budgetary restraints would prohibit any short term production of new tanks anyway. When in 1922 General Jean-Baptiste Eugène Estienne made a plan for long term tank design, no new light infantry tank was foreseen.

[edit] FT Kégresse

However the existing FT-17s, though having shown themselves to be very effective in trench warfare, were not well adapted to peacetime conditions. The main problem was their low top speed, which necessitated the use of special tank carriers whenever the tanks had to be moved outside of their base and which made them fundamentally unsuited for patrolling duty in the colonies. It was therefore decided to modify some existing vehicles, fitting them with a more effective suspension system. The first modifications were of the FT Kégresse-type, which featured the suspension of the Kégresse half-track, fitted with a special rubber steel-reinforced track. In 1925 42 vehicles were rebuilt and employed the next year during the Berber insurrection in Morocco. The modification allowed for a top speed of 17 km/h but experience in the field showed that the track was liable to suddenly snapping and the project was discontinued. Nine vehicles were later sold to Yugoslavia, five to Poland.

[edit] Renault NC

Meanwhile Louis Renault had in 1923 obtained an order to build two prototypes for a parallel development, the Renault NC, also incorporating a stronger engine. Like "FT", "NC" is a simple code devoid of any meaning. The second prototype to be finished, in December 1925, and that therefore was called the NC2, featured a strongly modified Kégresse leaf spring suspension and a 62 hp engine. It was also called the Modèle 24/25, because Renault put it forward as a possible fast tank as specified in the Plan 1924 of the French Cavalry. This line of development was discontinued however. The first prototype to be ready, thus named the NC1, had a completely different suspension system, with twelve wheels per side and three large vertical volute springs. It allowed for a top speed of 18.5 km/h, making it the fastest French tank then built.

This project was still intended to result in a modification proposal for existing FT-17s. In 1926 it transpired however that the Char de Bataille project, that later would bring forth the Char B1, was developing into a far heavier tank than at first hoped for. It would be impossible to procure this heavier design in sufficient numbers and therefore specifications were made in the Plan 1926 for a new Char léger d'accompagnement d'infanterie. Renault immediately tried to offer his NC1, now called the Modèle 26/27, as the logical candidate for this role.

Renault also tried to open foreign markets. In 1928 he sold a single prototype to Sweden, there named the Stridsvagn fm/28; in 1929 ten vehicles to Japan, there called the ETSU-B; and 24 were delivered to Poland, fitted with 25 mm side armour, bringing the weight from 7.5 to 9.5 metric tons. All these vehicles were by later authors subsumed under the name NC27; this is not a contemporary designation however.

[edit] NC31

In 1928 Renault was indeed granted an order to build two prototypes. The Army called this project the Char D, Renault used the designation NC28. Of the two prototypes the first was fitted with the twin machine gun turret of the SRA Char de Bataille prototype. Also a new suspension system was tried incorporating the special chenille légère of Colonel Balland, optimised for high speeds. As this vehicle was a derivative of the NC1, it was later indicated with the designation NC2, creating confusion with the earlier project of that name. The Army made a choice in March 1929 for the second prototype, the NC3 gun tank, and ordered a pre-series of ten vehicles in December 1929. These had the Renault factory designation NC31, after the year of delivery. Renault merely had to build the hulls at a price of 400,000 FF each; the cast turrets were ordered at the Schneider company; they were of the ST1 type (Schneider Tourelle 1). As the turret is much wider than the previous FT-17 turret used, Renault broadens the hull accordingly; the typical tapering nose point of the FT-17 is abandoned. The ten hulls are delivered between May and November 1931: after an interval of ten years after the delivery of the last Char 2C, French tank series production for the home market is thus resumed.

The ten pre-series hulls are tested by 503e Régiment de Chars de Combat. Many shortcomings are discovered by the Commission de Bourges. Steering is difficult, the suspension is too weak and the exhaust pipes overheat the engine compartment. Nevertheless the type is accepted for mass production — the commission had little choice in this as the main series had already been ordered — provided that changes are made. The strangely squeezed ST1 turret, first delivered in November 1930, is rejected though as being unacceptably cramped: each time the gun is loaded the breech has to be lowered into the fighting compartment, otherwise the round cannot be shoved in.

[edit] Char D1

On 23 December 1930 a first order of seventy main production series vehicles was made, followed on 12 July 1932 by a second order of thirty; the last order on 16 October 1933 is of fifty vehicles, for a total of 150, delivered between January 1932 and early 1935, at a price of 375,000 FF per hull. Including the NC31s the series numbers are 1,000-1,160. The factory designation is still Renault NC.

The series vehicles have many improvements: a Cleveland differential; a 74 hp engine instead of a 65 hp; the exhaust pipes are to the right, no longer crossing the engine room; there are support rollers to prevent resonation in the top track run; the fuel tank has been enlarged to 165 liters and a new radiator is fitted.

In May 1930 Renault was asked to develop two derived types, the Char D2 and the Char D3; the original Char D now became the Char D1.

[edit] Description

The Char D1's FT-17 ancestry can still be seen from the sloping engine deck and the profile of the side plates; it is also still a rather narrow vehicle, only 2,16 metre wide. Its length is 5,76 metre with tail. The rivetted hull armour is thirty mm thick on all vertical surfaces, ten mm on top and bottom. The NC31 introduced a 10 mm protection plate for the suspension units; the lower hull side armour beneath it was probably 16 or 25 mm thick — the exact data have been lost. For its time the Char D1 was relatively well armoured; as a result the hull alone weighs 11 metric tons, rather heavier than a typical light tank of the period. A 74 hp V-4 engine of 6.08 litre renders a top speed of 18.6 km/h; the range is ninety kilometres; it can climb a 110 cm obstacle and a 50% slope, cross a 220 cm trench and wade through 90 cm of water. The type thus has a reasonable mobility for the early thirties. In the hull are two crew members. The first is the driver who, as with the FT-17, is seated below large double hatches that form the nose plates. He can operate, via a steel cable, a fixed 7.5 mm Reibel machinegun low in the nose, that is almost completely hidden behind the armour. The second crew member operates the radio set on the right side of the fighting compartment, being an ER (Émetteur-Récepteur) 51 for the NC31s and an ER52 or 53 for the series vehicles. At the right of the engine deck a very distinctive and robust radio antenna frame is fitted, its point the highest of the vehicle at 2.4 metres. The radio operated also assists in the loading of the gun, by handing over rounds taken from the munition load of 76 to the third crew member, the commander, located in the turret.

As the ST1 turret type had been rejected, a new one had to be developed. Until that time all 160 Char D vehicles were fitted with existing FT-17 turrets, taken from the FT-17 materiel reserve. Two new turret designs were proposed by Schneider. The ST3 was a modification of the ST1. To solve the problem that not enough room was availble to normally load the gun, this type had a lightly armoured extension at the back, with a large square opening. A hatch at the back of the main armour hinged at the top and could be opened to fit into the extension, closing the square hole and providing enough room to load the gun. This way the commander would still be protected against small arms fire, without the weight penalty of a larger turret. The materiel commission judged this system, though ingenious, to be hugely impractical — it made the turret more vulnerable in precisely those situations where its was most likely to be hit: when fighting the enemy — and decided to accept the penalty, chosing the alternative ST2 that was simply a larger turret, weighing three metric tons.

The ST2 turret had a very complicated geometry with many shot traps. This was partly caused by the large extending diascopes at the sides, but also a result of forcing the commander to operate in three height levels: he had to stretch himself to observe his surroundings via the cupola, had a front observation hatch that he could look through while standing normally and had to crouch to operate the 47 mm SA34 gun to the right of him and the coaxial 7.5 mm machine gun to the left. The lower level had its own extension, where room had been found, not in the back as with the ST3 but in the front of the turret. Needless to say, the army was very critical of this arrangement, but it couldn't be rejected as deliveries were already greatly delayed: the first replacement turrets were fitted only in early 1936.

The ST2, weighing 1788 kg, brought total weight to fourteen metric tons and, costing 100,000 FF per piece, the total vehicle price to 475,000 FF. The Char D1 was thus neither particularly light nor cheap, causing the Hotchkiss company to propose a design better conforming to the role of mass produced light infantry tank, which proposal would result in no less than three production types: the Hotchkiss H35, Renault R35 and FCM 36. However, even in 1926 the project had been seen as more of a cheaper alternative to the Char B than as a pure light infantry tank; the political situation of the early thirties would force the Char D1 completely into the role of "battle tank".

[edit] Operational History

[edit] Char de Bataille

A picture with a Char D1 in the middle, on the left a R 35 can be seen, on the right a FT-17 rebuilt as bulldozer

In 1932 the Char D1 was the most — indeed the only — modern tank materiel available to the French Army. Therefore it was out of the question to delegate this type to the role of mere infantry support. It now should function as the Char de Bataille, with the main task of fighting enemy armour, as was shown by the choice for a 47 mm gun and the presence of radio sets. The ten NC31s were used for driver training; the other vehicles were allocated to three battalions, one each in the 507, 508 and 510 RCC, the elite tank units. As the threat of war steadily increased, first through the Soviet military build-up and then because of Germany's rearmament, the modern equipment was supposed to show to the larger world that France was still a force to be reckoned with. For the receiving regiments the new tank was a grave disappointment however. The main reason for this, besides the fact that the obsolete FT-17 turrets had to be used for the first four years, laid in its very poor mechanical reliability. In March 1934, when 110 vehicles had been delivered, it was reported that seventeen of these were already worn out and had to return to the factory for a complete rebuild; of the remaining 93, 62 were inoperational because of major defects. The burn-through of brakes and transmissions was common; the armour plates were bended out of shape because the chassis wasn't stiff enough, their rivets regularly snapping. The fundamental cause of this was that the Renault design team tended to combine low weight with low cost by applying inferior and weak components: the AMR 33, AMC 35 and Char D2 suffered from comparable problems. In 1935 a large maintenance programme was started; but when in March 1936 the elite units had to hurry to the German border because of the Rhineland Crisis, it became painfully obvious how poor their readiness still was. The new ST2 turret only worsened the situation: the glass of the diascopes was discovered to shatter by mere driving; there was no AP-shot available, except for about twenty tanks equipped with the naval 47 mm gun, fitted because the regular SA34 was in short supply; the munition racks hadn't yet been changed to hold the larger rounds. The SA34 was too weak a gun anyway; but the turret was too small to be adapted to the much more powerful 47 mm SA35. It was concluded that the Army should rid itself as soon as possible of the troublesome materiel. Early 1937, when newer types had come available, all Char D1s in mainland France were phased out, with the exception of the NC31s.

[edit] In exile

The tanks were now shipped to the typical destination of army ordnance that was unusable but too valuable to be scrapped: the colonies. In 1937 they arrived in North-Africa, there to form three new battalions, 61, 65 and 67 BCC, to counter Italy's threat to invade and annex Tunesia. As the organic strength of each battalion was 45, and one tank had been used to build a radio tank, fourteen were in the materiel reserve. Remarkably, in view of the fact that even a reserve of this size was insufficient, a Cavalry unit, 5e Chasseurs, was allowed to appropriate twenty tanks for its own use, without any proper authorisation for this.

[edit] Return to France

In May 1940, during the Fall of France, it was decided after the German success of Fall Gelb, to reinforce mainland France with the North-African battalions. Predictably, the readiness of the Char D1s had in the meantime only worsened. It was decided to concentrate all 43 operational vehicles in 67 BCC, the first unit to be shipped to France. As Italy hadn't yet declared war, the battalion reached France in relative safety in early June.

On 9 June the main attack of Fall Rot began and on 11 June the German Panzerdivisionen attained a breakthrough. To cover the retreat, 67 BCC on 12 June reinforces the Senegalese 6th Mechanised Infantry Division in a blocking position in the village of Souain to stop 8PD. The battalion repulses the first German attacks, destroying four tanks. When it tries to counterattack from the side, naively trusting the "shock effect" of tanks, it is hit in the flank by 37mm anti-tank fire and loses seven vehicles itself. Further German attacks are beaten off, again destroying some enemy tanks. When it transpires the Germans murder all black prisoners of war, it is decided to attempt a withdrawal to the south during the night. In this attempt the battalion is ambushed, losing all its vehicles.

Of the 43 participating Char D1s, 25 are totally destroyed; eighteen are captured by the Germans and given the designation Panzerkampfwagen 732 (f). There is no documented German use of the materiel.

[edit] Last Fights

Under the armistice conditions, France was in principle allowed to keep its remaining (in fact 106) Char D1s in North-Africa. However pure tank units had to be disbanded and only 62 tanks were divided among 2 and 4 Chasseurs d'Afrique, about 45 and 20 respectively plus two tanks for driver training. This posed a problem for 5e Chasseurs that still held the twenty clandestine vehicles; only 86 vehicles had been reported. When the Italian armistice control commission visited, the tanks were successfully hidden behind the stable for mad horses.

After Operation Torch the French troops rejoined the Allies. The Char D1s were concentrated into the Brigade Légère Mécanique and fought during the Battle of Kasserine Pass, even destroying a Panzerkampfwagen IV, which was quite a feat given the poor anti-armour capacity of the 47 mm SA34 gun. Pictures show that the radio frame, that impeded a full rotation of the turret, had been removed. In March 1943 all seventeen surviving Char D1s were phased out in favour of the Valentine tank. Today not a single Char D1 survives; the only extant related vehicle is one "NC27" in Sweden.

[edit] The Char Observatoire

To ensure adequate coordination between tanks and artillery during modern manoeuvre warefare, good radio connections are essential. The Plan 1934, outlining future tank design, therefore foresaw the production of a special radio tank, the Char Observatoire that wasn't, as its name might suggest, itself an artillery observation vehicle, but had to transmit information, gathered by the real observation vehicles of the Renault YS type, to the artillery units. In early 1937 at 507 RCC, Charles de Gaulle's regiment, a single Char D1, series number 1016, was rebuilt as such. Its turret was removed and replaced by an octogonal superstructure on the right side, making room for an extra ER51 long distance set at the left side of the hull. Only one vehicle was experimentally modified. After the war it has long been assumed that the surviving pictures of this vehicle showed a presumed command tank, the Char Colonel.

[edit] External links

• Specifications and Description