Littorio Class Battleship - Design

Design

The Washington Naval Treaty of 1922 allotted Italy an additional 70,000 long tons (71,000 t) of total capital ship tonnage, which could be used in 1927–1929, while other powers were observing the "holiday" in battleship construction prescribed by the treaty. France, which was given parity with Italy, also possessed 70,000 tons of capital ship tonnage. Both countries were put under significant pressure from the other signatories to use their allotted tonnage to build smaller battleships with reduced caliber main batteries. The first Italian design, prepared in 1928, called for a 23,000 long tons (23,000 t) ship armed with a main battery of six 381 mm (15.0 in) guns in twin turrets. They opted for this design because this allowed three ships under the 70,000-ton limit. Protection and radius of action were sacrificed for speed and heavy armament, though the Italians did not value range, as they operated primarily in the confined waters of the Mediterranean.

Later in 1928, the design staff prepared an alternative ship, with a displacement of 35,000 long tons (36,000 t), armed with 406 mm (16.0 in) guns and protected against guns of the same caliber. Funding was not allocated to begin construction, however, as the Italian Navy did not want to instigate an arms race with the French Navy. The London Naval Treaty of 1930 extended the building holiday to 1936, though Italy and France retained the right to build 70,000 tons of new capital ships. Both countries rejected British proposals to limit new battleship designs to 25,000 long tons (25,000 t) and 305 mm (12.0 in) guns. After 1930, the Italian Navy abandoned the smaller designs altogether. By 1932, Germany had begun to build the Deutschland class ships, armed with six 280 mm (11 in) guns, and France had in turn laid down the Dunkerque-class battleships to counter them. The French vessels were armed with eight 330 mm (13 in) guns. In late 1932, Italian constructors responded with a design similar to the Deutschland class, but armed with six 343 mm (13.5 in) guns in triple turrets on a 18,000 long tons (18,000 t) displacement.

The Italian Navy decided that the smaller design was impractical, and that a larger design should be pursued. A 26,500 long tons (26,900 t) design was then prepared, which mounted eight 343 mm guns in twin turrets. This was ultimately abandoned in favor of a 35,000 ton design to be armed with 406 mm guns. The 406 mm gun was abandoned in favor of the 381 mm gun because there were no designs for the larger gun, which would delay construction. The 381 mm gun had been designed for the canceled Caracciolo class. Ultimately, nine 381 mm guns in three triple turrets were adopted as the primary battery for the ships, on a displacement in excess of 40,000 long tons (41,000 t), despite the fact that this violated the established naval treaties.