South Dakota class battleship (1920)
Encyclopedia
The first South Dakota class was a class of six battleship
s, laid down in 1920 but never completed. These battleships would have been the last dreadnought
s to be commissioned, if the Washington Naval Treaty
not caused their cancellation one-third of the way through their construction, they would have been the largest, most heavily armed and armored battleships in the U.S. Navy
in the period between the two world wars. Designed to achieve 23 knots, they represented the first attempt made by the US Navy to abandon their 21 knot standardised fleet speed and catch up with the increasing fleet speeds of their main rivals, the British Royal Navy
and Imperial Japanese Navy
.
The preceding s were 624 feet (190.2 m) long, displaced 32,600 tons, had a top speed of 21 knots (41.2 km/h), and carried a main battery of eight 16 inches (406 mm) guns. Although the Colorados were the largest US battleships of the time, and were the first to carry 16 inches (406 mm) guns, they were the endpoint of the gradual evolution of the "Standard Type" battleships, which also included the , , , and . The South Dakotas represented a significant increase in size and armament over the Colorados. They would have been 684 feet (208.5 m) long, displaced 43,200 tons, had a top speed of 23 knots (45.1 km/h), and carried 12 16 inches (406 mm) guns.
The South Dakotas were authorized 4 March 1917, and keels were laid down in 1920. However, as the Washington Naval Treaty
restricted both the total allowable battleship tonnage allowed the U.S. Navy, and limited individual ship size to 35000 tons, construction was halted 8 February 1922, and the unfinished hulls (most over 30% completed) were scrapped in 1923. Some of the material from the uncompleted ships was used in the reconstruction of the remaining U.S. battleships that was allowed under the terms of the treaty. The armor plate in storage that was reserved for Indiana was used to reinforce the defenses and locks at the Panama Canal
. The 16" guns were transferred to the US Army as 16"/50 caliber M1919 gun.
The South Dakota class was ordered in the same program that created the s, two of which were converted to aircraft carrier
s. The Lexingtons made better conversion hulls than the South Dakotas because they were further along in their construction and were designed for a far higher speed.
Battleship
A battleship is a large armored warship with a main battery consisting of heavy caliber guns. Battleships were larger, better armed and armored than cruisers and destroyers. As the largest armed ships in a fleet, battleships were used to attain command of the sea and represented the apex of a...
s, laid down in 1920 but never completed. These battleships would have been the last dreadnought
Dreadnought
The dreadnought was the predominant type of 20th-century battleship. The first of the kind, the Royal Navy's had such an impact when launched in 1906 that similar battleships built after her were referred to as "dreadnoughts", and earlier battleships became known as pre-dreadnoughts...
s to be commissioned, if the Washington Naval Treaty
Washington Naval Treaty
The Washington Naval Treaty, also known as the Five-Power Treaty, was an attempt to cap and limit, and "prevent 'further' costly escalation" of the naval arms race that had begun after World War I between various International powers, each of which had significant naval fleets. The treaty was...
not caused their cancellation one-third of the way through their construction, they would have been the largest, most heavily armed and armored battleships in the U.S. Navy
United States Navy
The United States Navy is the naval warfare service branch of the United States Armed Forces and one of the seven uniformed services of the United States. The U.S. Navy is the largest in the world; its battle fleet tonnage is greater than that of the next 13 largest navies combined. The U.S...
in the period between the two world wars. Designed to achieve 23 knots, they represented the first attempt made by the US Navy to abandon their 21 knot standardised fleet speed and catch up with the increasing fleet speeds of their main rivals, the British Royal Navy
Royal Navy
The Royal Navy is the naval warfare service branch of the British Armed Forces. Founded in the 16th century, it is the oldest service branch and is known as the Senior Service...
and Imperial Japanese Navy
Imperial Japanese Navy
The Imperial Japanese Navy was the navy of the Empire of Japan from 1869 until 1947, when it was dissolved following Japan's constitutional renunciation of the use of force as a means of settling international disputes...
.
The preceding s were 624 feet (190.2 m) long, displaced 32,600 tons, had a top speed of 21 knots (41.2 km/h), and carried a main battery of eight 16 inches (406 mm) guns. Although the Colorados were the largest US battleships of the time, and were the first to carry 16 inches (406 mm) guns, they were the endpoint of the gradual evolution of the "Standard Type" battleships, which also included the , , , and . The South Dakotas represented a significant increase in size and armament over the Colorados. They would have been 684 feet (208.5 m) long, displaced 43,200 tons, had a top speed of 23 knots (45.1 km/h), and carried 12 16 inches (406 mm) guns.
The South Dakotas were authorized 4 March 1917, and keels were laid down in 1920. However, as the Washington Naval Treaty
Washington Naval Treaty
The Washington Naval Treaty, also known as the Five-Power Treaty, was an attempt to cap and limit, and "prevent 'further' costly escalation" of the naval arms race that had begun after World War I between various International powers, each of which had significant naval fleets. The treaty was...
restricted both the total allowable battleship tonnage allowed the U.S. Navy, and limited individual ship size to 35000 tons, construction was halted 8 February 1922, and the unfinished hulls (most over 30% completed) were scrapped in 1923. Some of the material from the uncompleted ships was used in the reconstruction of the remaining U.S. battleships that was allowed under the terms of the treaty. The armor plate in storage that was reserved for Indiana was used to reinforce the defenses and locks at the Panama Canal
Panama Canal
The Panama Canal is a ship canal in Panama that joins the Atlantic Ocean and the Pacific Ocean and is a key conduit for international maritime trade. Built from 1904 to 1914, the canal has seen annual traffic rise from about 1,000 ships early on to 14,702 vessels measuring a total of 309.6...
. The 16" guns were transferred to the US Army as 16"/50 caliber M1919 gun.
The South Dakota class was ordered in the same program that created the s, two of which were converted to aircraft carrier
Aircraft carrier
An aircraft carrier is a warship designed with a primary mission of deploying and recovering aircraft, acting as a seagoing airbase. Aircraft carriers thus allow a naval force to project air power worldwide without having to depend on local bases for staging aircraft operations...
s. The Lexingtons made better conversion hulls than the South Dakotas because they were further along in their construction and were designed for a far higher speed.
Ships in class
- USS South Dakota (BB-49)
- USS Indiana (BB-50)
- USS Montana (BB-51)
- USS North Carolina (BB-52)
- USS Iowa (BB-53)
- USS Massachusetts (BB-54)