The Battleship Richelieu

Visualization 3D Andrzej Sobucki and Piotr Forkasiewicz

First intelligence reports concerning the construction of the Deutschland class influenced the decision to change the requirements for the so-called “battle cruisers”. Displacement of the designed battleships was between 23 000 and 35 000 tons and the armament would consist of 305 or 330 mm guns, although designs that would mount 380 and 406 mm guns were also considered. The French navy changed its requirements concerning armour protection and in 1930 demanded that it should withstand 280 mm projectile hits. The design presented by STCN called for 25 000 tons displacement, armament of eight 305 mm guns mounted in two quadruple turrets and the speed of between 29 and 30 knots. Design of the first battleship, named Dunkerque was finished in 1931 and its final version was ready on April 27, 1932. The construction of the second unit was hastened by the information received in May 1934, when Mussolini informed the public that keels of two new Italian battleships had been laid down. These ships were considered a threat to the Marine Nationale in the Mediterranean area which the French government could not allow. In reply the French government authorized construction of the second battleship named Strasbourg. Design study of a new battleship was also commenced. The new unit was based on the Dunkerque class. Vice Admiral Durand-Viel, the Chief of the Navy’s General Staff, argued that France needed homogenous combat groups. Moreover, he was of the opinion that the new warships should be constructed as soon as possible. At that time design studies took a considerable amount of time, therefore, it was decided to modify the existing design and adapt it for the presented requirements: main battery made of 380 or 406 mm guns and maximum speed of 29.5 to 32 knots. Underwater protection would be identical to that of the Dunkerque class. After preliminary calculations, it was determined the use of 406 mm main battery guns was impossible as the heavy turrets would affect stability and increase displacement. It must be remembered that the requirements called for two quadruple turrets in forward superfiring position like on the Dunkerque class. Therefore, it was decided to mount smaller calibre 380 mm guns. Taking into consideration basic requirements, STCN prepared six preliminary battleship designs and presented them for consideration by the Conseil Superieur de la Marine on November 27, 1934. All of these included main battery located in the forward section with secondary battery aft. Two of the designs included the main battery of six 406 mm guns in two triple turrets. However, members of the Council considered such solution inadequate and insisted on nine gun main battery. The chief designer of the navy pointed out that at the displacement of 35 000 tons this was only possible by either reducing speed or protection, as was in the case of the British battleship Nelson.

Details of the main battery Turret II and the port side of the forward superstructure with the fittings installed during modernization in the USA. An access ladder was installed on the slope of Turret II that allowed the Oerlikon gun crews to reach their stations. Visualization 3D Andrzej Sobucki

The first four designs with the proposed 380 mm main battery were approved. According to the 1935 program the construction of the new battleships was scheduled to commence in mid 1935 and they were to be commissioned in 1939. At the early stage of the design studies CSM and STCN looked into division of the secondary battery into two calibres, which at that time was practiced on both German and Italian warships. It was stressed that both 152 mm and 75 mm had to be dual-purpose. During the CSM session on April 14, 1935 the final design of a battleship was examined. The CSM approved the location of the secondary battery turrets and rejected the use of 75 mm guns. Moreover, it agreed with the STCN proposal concerning the reduction of armour thickness to retain the non-extendible displacement of 35 000 tons. The alterations were promptly incorporated into the design, which resulted in creation of a modern battleship. It must be noticed, that work on the project was not hindered by various decisions made during the conferences by the Command of the Navy. It could be credited to the well refined design of the Dunkerque class, which was the base for the new battleships.

Table 2. Preliminary battleship design requirements – April 4, 1935.
Standard displacement    37 960 tons
Full-load displacement     44 385 tons
Length overall    247.0 m
Waterline length    242.0 m
Waterline beam    33.08 m
Draft (designed)    9.17 m
Main battery    Eight 380 mm guns in two quadruple turrets.
Secondary battery    Fifteen 152 mm guns in five triple turrets.
Anti-aircraft battery    Twelve 37 mm guns (6 x II)
Twenty-four 13.2 mm machine guns (6 x IV)
Seaplane    Five Loire-Nieuport 130 aircraft  
Catapults    Two
Speed    31.5 knots
Power output     150 000 SHP
Fuel capacity    6 300 t
Main belt     360 mm sloped at 11.3°