The Yorktown class was a class of three aircraft carriers built for the United States Navy and completed shortly before World War II, the , , and . They immediately followed , the first U.S. aircraft carrier built as such. As Ranger was not commissioned until two weeks after Yorktown was laid down, experience with that vessel did not influence the design of the Yorktown ships; rather, the design was influenced most strongly by experience with the Lexington-class ships, built on the partially completed hulls of two battlecruisers and commissioned in 1927, and the early experimental carrier Langley, commissioned in 1924.
The Yorktown-class ships bore the brunt of the fighting in the Pacific during 1942, and two of the three were lost: Yorktown, sunk on 07 June 1942 after the Battle of Midway, and Hornet, which was heavily damaged by the Japanese at the Battle of the Santa Cruz Islands, and survived attempts at scuttling by the US Navy, but was finally sunk by the Japanese.
Enterprise, the sole survivor of the class, was the most decorated ship of the U.S. Navy in the Second World War. After efforts to save her as a museum ship failed, she was scrapped in 1958.
Development After the commissioning of the two 33,000-[long] ton (33,530-tonne) Lexington class ships in 1927-28, a strong sentiment arose within the Navy that the remaining 69,000 tons (70,107 tonnes) of carriers allowed under the Washington Naval Treaties should be built as quickly as possible. The idea that the additional tonnage should come in the form of multiple ships built to a single design was also widely accepted, but different factions advocated for three different packages--either five ships, displacing 13,800 tons (14,021 tonnes) each, or four ships, displacing 17,250 tons (17,527 tonnes) each, or three ships, displacing 23,000 tons (23,369 tonnes) each. The consensus as of the late 1920s was that the largest number of decks would offer the greatest total aircraft capacity, and a decision was then made to order the five small carriers. For once, government parsimony proved beneficial; Congress, on 13 February 1929, authorized construction of only one of the 13,800-ton carriers, which became Ranger. Years passed before funding for additional carriers was approved, and by the time it was, experience with Lexington and Saratoga had demonstrated the pronounced advantages of larger carriers, to such a degree that even before Ranger was commissioned, the selection of such a small, slow, and poorly protected design was widely considered to have been unwise.
The desirability of larger size having been settled on, in the early 1930s, the question of exactly how to use up the tonnage remaining under Washington Treaty limits arose once again, leading to the development of a new series of schemes. Factoring in Ranger, designers now had about 55,200 tons (56,086) tonnes left with which to work. Again, one faction argued for the creation of a uniform class, now to consist of three, 18,400-ton (18,695-tonne) carriers, to fill the quota, but a strong opposing faction wanted to incorporate more of the features found on the much larger Lexington ships (high speed, torpedo protection, and an armored belt, any one of which would have been difficult to accommodate on an 18,400-ton displacement) into at least some ships. The General Board eventually settled on the idea of building two fairly large (about 20,000-ton/20,321 tonne) carriers incorporating 32.5-knot speed, armor, and substantial underwater protection, and one smaller, roughly 15,000-ton (15,241-tonne) vessel, broadly similar to the large ones, but lacking the protective features. The smaller carrier would eventually become Wasp, while the larger two became Yorktown and Enterprise. General designs for these two classes of ships were chosen from among a common slate of 15 draft designs presented to the General Board in 1931 by the Bureau of Construction and Repair. All 15 of these schemes included islands, long opposed by the Bureau of Aeronautics, but due to operational experience accumulated with the Lexington ships by 1931, now considered desirable. Funding for construction of the two larger ships came with the National Recovery Act, passed on June 16, 1933, and Yorktown was laid down on May 21, 1934, two weeks before Ranger was commissioned. Enterprise was laid down on July 16, 1934. Work on the smaller Wasp was delayed for some time, but was ultimately authorized under the Vinson-Trammel Act of 1934, and construction, to essentially the specification laid out in 1931, began in 1936.
Two days after Enterprise was commissioned, in May 1938, partly in response to the withdrawal of Italy and Japan from the global naval arms limitation treaty structure, Congress passed the Naval Act of 1938, which authorized a major expansion of the Navy, including construction of 40,200 additional tons (40,845 tonnes) of aircraft carriers. After considerable debate and dithering, the Navy decided that to get a ship in service as quickly as possible, roughly half of this extra tonnage would be given over to building a third ship to a minimally modified Yorktown design, while time was spent figuring out how best to use the remainder. The third Yorktown-class ship, Hornet, was ordered in March 1939 and commissioned only a month before Pearl Harbor.
Each Yorktown-class ship was built with a transverse catapult on her hangar deck; these could launch aircraft in a direction perpendicular to the direction of the ship's motion, or while the ship was at anchor. These catapults were intended as substitutes for the lower-level flying-off decks that had been adopted by the British and Japanese in the 1920s, which allowed aircraft to be launched straight forward off both the upper flight deck and the deck below it at the same time, allowing the launch of more aircraft quickly in a scramble situation. Statements that the transverse catapults were intended to be used primarily for the launching of scout planes appear to be unfounded; all readily available photos of these catapults in use depict the launching of combat aircraft (fighters and torpedo bombers), rather than scouts. In practice, the U. S. commanders rarely used the hangar-deck catapults because of the difficulties inherent in controlling a plane launched across a heavy crosswind, which would inevitably be faced when the ship was moving forward at high speed to allow aircraft to be flown off the axial flight deck at the same time. The hangar-deck catapults were removed from Enterprise and Hornet in late June 1942.
All three ships of the Yorktown class were built at the Newport News Shipbuilding Company, Newport News, Virginia.
Design The Yorktown-class ships had a length of at the waterline and overall. They had a beam of at the waterline and overall, with a draft of as designed and at full load. They displaced around at standard load and at full load. Notations on blueprints for Yorktown (dated 30 January 1939) indicate that the ship was intended to carry a crew of 83 officers, 90 chief petty officers (CPOs), and 1346 enlisted men, along with an aviation component consisting of 108 officers, 66 CPOs, and 538 enlisted men, plus an "extra complement when squadrons are aboard".
Each ship was powered by nine Babcock & Wilcox boilers providing steam at and to four Parsons Marine geared steam turbines, each driving its own propeller. The turbines were designed to produce a total of , giving the ships a range of at a speed of . The ships were designed to carry of fuel oil and of avgas. Designed top speed was . During sea trials, she produced and reached .
The ships were equipped with eight /38 caliber dual-purpose guns and 16 /75 caliber antiaircraft (AA) guns in quadruple mounts (four guns operating together). Originally, she had 24 M2 Browning machine guns, but these were replaced in January 1942 with 30 20-mm Oerlikon AA cannons. An additional quad mount was later added at her bow and two more 20 mm AA guns were added for a total of 32 mounts. In June 1942, following the battle of Midway, Hornet and Enterprise had new CXAM radar installed atop their tripod masts, and their SC radars were relocated to the main mast. Unlike her sister ships, Hornets tripod mast and her signal bridge were not enclosed when the CXAM was installed, making her unique among the three ships.
The ships' flight decks measured 814 ft (248 m) in length and 86 ft (26 m) in width, and their hangar decks were 546 ft (166 m) in length and 63 ft (19 m) in width, with a clear height (distance from the floor to the lowest point on anything encroaching from above--in this case, the girder structure underpinning the flight deck) of 17 ft 3 in, and the underside of the flight deck itself about 10 ft higher up. The ships each had three centerline aircraft elevators, each measuring , with lifting capacities of . Each ship was built with two flight-deck hydraulic catapults pointing forward and a third catapult mounted transversely on the hangar deck; the latter were removed from Enterprise and Hornet in late 1942, after Yorktown had been sunk. All three ships were equipped with Mark IV Mod 3A arresting gear capable of bringing a plane to a halt from a speed of . Air groups when Yorktown and Enterprise were commissioned in 1938 consisted of four 18-plane squadrons (fighting, scouting, bombing, and torpedo), with six utility planes; while Hornet's first operational air group, on the eve of the Doolittle Raid, included a 30-plane fighter squadron (VF-8) equipped with F4F-4 Wildcats, scouting (VS-8), and bombing (VB-8) squadrons equipped with a total of 24 Douglas SBD-2 and -3 Dauntlesses, and a torpedo squadron equipped with 10 Douglas TBD-1 Devastators.