Renault DAC1

France (1939-1940)
Fast Tank – Project Only

In the 1930s, France had a vast tank industry with a large number of different manufacturers competing to provide armored fighting vehicles for the Army. The cavalry combat tank France adopted in 1935 and produced from that point onward was the Somua S35, a 19.5 tonnes, decently armored and mobile tank armed with the 47 mm SA 35. In the late 1930s, the project that was most probable in succeeding the Somua was an incremental evolution, the Somua S40. This did not mean, however, that other manufacturers were not seeking to produce designs to fulfill a similar role and potentially replace the Somua. Whilst AMX presented a fairly well-known design in 1940, the AMX 40, which would fulfill a similar role to the Somua, a much more obscure design was also created by Renault – the DAC1.

Le Somua de Billancourt

The DAC1 design by Renault appears to date from 1939 or 1940. The company had previously, in 1936, been stripped of its armored vehicles manufacturing service located in its factory of Issy-Les-Moulineaux, which was nationalized and became AMX (Atelier de Construction d’Issy-Les-Moulineaux – Issy-Les-Moulineaux Construction Workshop). Renault would, however, quickly resume its own tank-building efforts in its own facilities of Billancourt. Prior to the AMX split, Renault had designed some vehicles for the cavalry, including the AMR 33 and AMR 35 light reconnaissance tanks, but also the AMC 34 and AMC 35 tanks which fulfilled the same AMC role (Automitrailleuse de Combat – Combat Armored Car, with the term armored car designating any combat vehicle of the French cavalry in the interwar era, regardless of it using wheels, tracks, or half-tracks). Those designs, while having the advantage of a two-man turret, otherwise used riveted and bolted construction with thin armor, and the later iteration, the AMC 35, was notoriously unreliable. Renault did not produce any cavalry tank that could compete with the well-armored S35 produced by Somua.

The DAC1 appears to have been an attempt by Renault at creating such a vehicle, and the project received the name “Le Somua de Billancourt” (“The Billancourt Somua”). The project is incredibly obscure and is known from a single outline as well as very few specifications.

The DAC1 was to be a 16 tonnes fast tank with a crew of three. It has also sometimes been noted that it was a competitor to the AMX 38, a vehicle which was, by all means, an infantry tank, causing some confusion.

The vehicle’s profile indicates a gun that was most likely the 47 mm SA 35, the same armament as used in the second production run of the Renault D2, the Somua S35, and the B1 Bis. A coaxial machine gun, almost certainly a 7.5 mm MAC31E, would be present to the left of the gun. The design of the turret features a prominent cupola, more so than most French designs of the era.

The hull has a very basic shape, with a seemingly sloped frontal plate, and only a moderately-sized section appearing over the suspension, suggesting a fairly high suspension run. The only distinct elements of the hull appear to be what would suggest a rear transmission.

The suspension type the vehicle would have used is unknown, and it is uncertain if this was ever determined by Renault engineers. This would likely have been a suspension type at least to an extent optimized towards maximum speed, which would differentiate the DAC1 from several late 1930s vehicles, such as the R40, which opted for the “AMX-type” suspension with a large number of road wheels, optimized for cross-country mobility over road speed.

Planned American Exile

Prior to June 1940, France had some fairly deep military-industrial ties with the United States, with France being the largest foreign customer of the American military-industrial complex prior to the Fall of France. Armored fighting vehicles were not the main point of interest for the French in America, with American armored fighting vehicles of the time not really fitting in any role the French Army desired.

However, another way of using America’s vast automotive industry to provide France with armored fighting vehicles had been considered. This would have been employing American factories to manufacture vehicles designed by French manufacturers. While this would require some efforts, notably tooling-wise, it could potentially allow France to exploit a much larger industry than its own.

Already considered before the campaign of France, this option became increasingly popular during the month of May and early June 1940, when the situation of French troops and France’s ability to retain its territories looked increasingly bleak, but the negotiation of an armistice with Germany was not yet certain. The French would notably send a mission, reportedly headed by AMX engineer Joseph Molinié, to the US to evaluate such a possibility.

It appears the DAC1 was one of the various designs considered for production in the United States, though reportedly, the American-made DAC1 would have its crew reduced to just two. It is unclear why the DAC1 in particular was considered for production in the US. However, by picking a design that was yet not complete, perhaps it was hoped that the last design phases would be undertaken in US standards and would perhaps allow for an easier start of production, in comparison to adapting tools and plans of an already in production or fully designed vehicle, such as the B1 Ter or S40 to US measurements and production standards.

Conclusion – One of the Most Obscure French Tanks

Any plans to produce the DAC1, or another French tank for the matter, in the United States was abandoned after the armistice with Germany entered into effect on 25th June 1940. Later in the war, a secret service within the Vichy Army, bent on resisting the Germans, the CDM, would hope to produce some of its design, such as for example the SARL 42, in foreign countries, the US being the obvious contender. This would never materialize either.

The DAC1 is easily one of the most obscure French tank designs of the late 1930s, with very little known of the elements and capabilities the vehicle would have had. Nonetheless, its crew of two or three suggest it would have likely retained the one-man turret which plagued French tank designs of the 1930s, handicapping an otherwise sound design. At just 16 tonnes and with a 47 mm SA 35 armament, it is also likely such a tank would have been far from groundbreaking by the time it would reach prototype stage or enter production, and would not provide a good evolutionary potential for later stages of the war.

DAC1 specifications
Weight	16,000 kg
Transmission	Likely rear
Crew	2 to 3
Armament	Likely a 47 mm SA 35 main gun and coaxial 7.5 mm MAC31E machine gun
Numbers produced	0

Sources

Les véhicules blindés Français 1900-1944, Pierre Touzin, EPA editions, 1979
Tous les blindés de l’Armée Française 1914-1940, François Vauvillier, Histoire & Collection editions