The Standard Type

As it gained seagoing experience, the US Navy's dreadnoughts began to diverge from their British sisters. The Americans believed that long-range battle would be prevalent in future wars, and thus had begun with the New York class to fit the ships with the necessary fire control gear. However, it was not until the 1912 battleship design that the change took full effect.

Nevada, the first of the Standards

The USN concluded that at long ranges, the use of AP shells would dominate, as there was no way to control where on a ship hits would be made, and HE shells would be useless against belt and deck armor. As a result, it wasn't worth armoring against anything but AP shells, which required thick armor. Light armor would be a waste of weight and merely serve to burst the AP shells.¹ This scheme became known as all-or-nothing protection, and within a decade, the lessons of Jutland had resulted in its wide adoption by other nations.

Armor cross-section of Nevada

As implemented, it was in fact rather simple. The belt was 13.5" thick over most of its height of 17' 4 5/8", tapering down to 8" below the waterline. Sitting on top of it was a 3" armored deck, significantly heavier and higher in the ship than on previous American battleships. A deck below the main armor, there was a 1" splinter deck, intended to catch any fragments that might be driven through the main armored deck. At the edges, the splinter deck sloped to meet the bottom of the belt, with the slopes being 2" thick. This was an unprecedented level of protection against plunging fire, as well as a belt competitive with any other battleship of the time.

Oklahoma, sister to Nevada

Of course, protection of this quality was heavy, so the designers had to find ways to economize on length. The initial plans saw Turret 4 of the New York class removed, and the other four turrets converted to triples.² This would have seen Turret 3 remaining amidships, a configuration reminiscent of HMS Lion. However, reports soon came in of the failure of the magazine refrigeration system in the Delaware class, which resulted in poor shooting by Turret 3. The increased stiffness given by the raised armored deck allowed the turrets to be concentrated at the ends, solving the problem while keeping length down. Later, to hold the size of the ship down, Turrets 2 and 3 were changed to twins, matching the 10-gun broadside of the New York class.

Section of Nevada, including armor thicknesses

Length was reduced further by the adoption of oil fuel. Oil has considerably more energy per unit mass than coal, and is much easier to handle, allowing the engineering spaces to shrink considerably. Secondary benefit also came from the reduction in engineering personnel, as oil didn't have to be shoveled into the boilers.

Oklahoma on trials

The combination of the all-or-nothing armor scheme, the triple turret, and oil fuel was probably the single greatest change in battleship design since Dreadnought. The resulting Nevada class was not entirely without flaws, but their armament of 10 14" guns, two torpedo tubes, and 21 5" secondary guns made them formidable ships. The biggest weakness was the engines of the second unit of the class, Oklahoma. The US, concerned with endurance in fighting Pacific campaigns, but attracted by the greater reliability and power of turbines, chose to split the propulsion systems of the two ships, giving Nevada turbines and Oklahoma reciprocating engines. By the late 30s, Oklahoma's engines were getting increasingly old and difficult to use, and she was seen as by far the least useful of the Standards before her loss at Pearl Harbor.

Pennsylvania

The Nevadas set the pattern for the next four classes of American dreadnought, together known as the Standard Type. This is often seen as a triumph of planning and foresight, the USN simply knowing that they had a great design on their hands which only needed minor improvements. As is often the case, this is a dramatic oversimplification of the situation.

Arizona of the Pennsylvania class

The next class, the Pennsylvanias, were a fairly straightforward upgrade of the Nevadas, the main changes being the replacement of the twin 14" turrets with triples, and the final abandonment of the reciprocating engine.³ This drove up size about 15%, which irritated Congress, which had seen ship size grow 50% from the Delawares in the past five years. They refused to authorize more than one ship in FY13, followed by a second unit of the class the next year.⁴

Spring Style⁵ for largest FY15 battleship proposal

While this was going on, the Bureau of Ordnance was working on a 16" gun, which threatened to make the ships armed with and armored against 14" guns obsolete, much as the 14" gun had done to the 12" ships. A design that embraced this change was prepared for FY15, with a 16" belt, a 3.5" deck, 10 16" guns, 6" secondary batteries and the first anti-aircraft guns on a US battleship design. The total cost was 8,000 tons more than Pennsylvania, twice the jump from Nevada to that ship. However, the navy sensed that this was too much to ask and that it was too soon to introduce the 16" gun, and prepared a ship with the improved armor and secondary batteries, but only 4 14" triple turrets.⁶

New Mexico after WWI

Even this increase was too much for the Secretary of the Navy, Josephus Daniels. He rejected the design, and instead mandated that a version of the Pennsylvania class be submitted to Congress as Battleship 1915. The one major improvement he agreed to was the use of separate slides for the guns, although the navy designers managed to squeeze out more. A clipper bow was fitted to reduce wetness, and many of the secondary guns were placed in the superstructure instead of in the wet casemates that had been common on previous American battleships. The 14"/45 guns used on the previous two classes were replaced with 14"/50s, and the deck was thickened from 3" to 3.5". Two pre-dreadnoughts were sold to Greece to allow a third unit of the resulting New Mexico class to be purchased in 1915. The name ship of the class also served as the prototype of another major innovation, turboelectric propulsion. This allowed the turbine speeds to be decoupled from the propeller speed, giving greater endurance. The system was also cheaper, lighter, and more robust, and it was incorporated into later US battleships.

California, sister to Tennessee. Note the lack of casemates.

For the 1916 ship, the General Board sent Secretary Daniels the characteristics it had submitted the previous year,⁷ and again Daniels instructed that an improved version of the previous year's ship be sent to Congress instead. The Tennessee class was designed around turboelectric drive from the start. This allowed a massive improvement in resistance to underwater damage. The new propulsion system was more compact, giving space for a new and very effective Torpedo Defense System, and allowed much greater subdivision of the machinery spaces in case the TDS was breached.⁸ The turret elevation was also increased from 15° to 30°, increasing range, and various detail improvements were made.

Design drawing for the Colorado class

The FY1917 construction plan saw the same drama of the previous two years play itself out again. The 16" gun was now ready, and battles in the North Sea had revealed that combat would take place at a longer range than previously anticipated. As a result, the Board sent in a proposal for a ship of the same size as the last two proposals, but with 10 16" guns and a thinner belt. Daniels again refused to sanction a bigger ship, and demanded a repeat of the Tennessee, except for giving the General Board the option of triple 14" or twin 16" armament. They chose the 16" gun, and four units of the Colorado class were authorized as part of the massive 1916 Naval Act, although one, Washington, was cancelled under the Washington Naval Treaty and later used for armament testing.

Colorado in 1924

The story of the Standard Type came to an end with the Colorados. While the Standards had been the result of political pressure to hold down ship sizes, and not careful planning as is commonly assumed, the ships made up the backbone of the American battlefleet during the interwar era. The ships sunk at Pearl Harbor were Standards, and most of them were salvaged and went on to have illustrious careers in World War II. The last salvo ever fired at one battleship from another came from a Standard, USS Mississippi.

These ships were a weird hybrid, designed before WWI, but in many ways more similar to the ships that came from the lessons of that war than they were to their contemporaries. However, they provided the US with a first-rate interwar fleet, as the next class of US battleships would never be built, victims of the axe wielded in Washington. We'll look at those ships, and the others that died on the table, in later installments.