Lexington Class Battle Cruiser - Construction Hold and Redesign

Construction Hold and Redesign

Plans to begin construction were placed on hold in 1917. Large numbers of anti-submarine warfare vessels and merchant ships were needed to ensure the safe passage of men and materiel to Europe during Germany's U-boat campaign and were given top priority. This opened the opportunity for a massive redesign, the need for which had become apparent in light of experience gained in the Battle of Jutland, fought shortly after the initial design for the Lexingtons had been approved and in which three British battlecruisers had been lost. The fact that the U.S. Navy misunderstood the essential points of the battle initially was shown by its ignoring the Lexingtons staying power while increasing their main armament to eight 16"/50 caliber guns and their secondary armament to fourteen 6"/53 caliber guns. Other factors for this decision were the discovery of plans by Britain and Japan for new battlecruisers armed with 15- and 16-inch guns (respectively) and the recommendation of the Bureau of Ordnance to give these ships the ability "to inflict fatal damage on the enemy's most powerful vessels at a distance no less than that at which she can be reached by the heavy gunfire of these opponent battleships." Developments in boiler design allowed the number needed to be reduced to 20, which allowed all of them to be moved below the armored deck and the number of funnels reduced to five. However, the armor scheme could not be modified with the design in its current shape without compromising the longitudinal strength of the hull.

Around 1918, the U.S. naval staff in Great Britain became extremely impressed by the British's newest battlecruiser, HMS Hood of the Admiral class. Her side armor was comparable to that of previous battleships and her deck armor was the most extensive of any British capital ship. Because this ship was described as a "fast battleship" and the British Admiralty considered her a replacement for both the battleship and the battlecruiser, the staff advocated that the United States should develop a similar vessel of its own. Chief Constructor David Taylor agreed. On 8 April 1918, he told the Lexington design staff to plan a vessel combining the principal features of battleship and battlecruiser so that it would have the maximum possible speed, main armament and protection. Specifically, this meant arming her with the 16" 50 caliber guns planned for the South Dakota class battleships, reducing armor protection 10 percent, a freeboard of at least 28 feet (8.5 m) (compared to 32 feet (9.8 m) for the 1917 battlecruiser and 29 feet (8.8 m) for the Hood) and a speed of at least 30 knots. Moreover, designs were to be prepared and submitted quickly.

The Royal Navy temporarily assigned a young constructor, Stanley Goodall, to C&R to assist in this task. Goodall brought a copy of the plans of Hood and accurate accounts of shell damage at the Battle of Jutland. In addition, a senior U.S. constructor who served on Admiral Sims's staff in London, L.C. McBride, became privy to much British experience and was able to share it with C&R. While C&R worked concurrently on the more conventional, more heavily armed and armored South Dakota class, it quickly adopted and incorporated ideas from Hood into the Lexington project which included a reduction of the main armor belt, the change to "sloped armor" and the addition of four above-water torpedo tubes that were added to the four underwater tubes that had been included in the original design. Other changes included a widening of the ship to allow for an adequate torpedo protection system and an increase in vertical belt armor to 7 inches (180 mm). A new type of boiler allowed the number needed to be reduced to 16 and the number of funnels to just two. These improvements, however, increased the normal displacement of the ship to 43,500 tons, which was 300 tons more than the South Dakotas and 10,900 tons greater than the previous battleship class, the Colorado class.

Four proposed redesigns were submitted to the General Board on 3 June 1918, along with a letter that requested a formal reconsideration by the Navy that the Lexingtons be armored to protect them only against fire of guns 6 inches (150 mm) and under. The Board, concerned about the delay incorporating any of the redesigns would have on not just the Lexingtons but the 1916 building program in general and the subsequent cost, declined all four designs. The Board also feared that producing heavily armored fast battleships such as Hood would make the U.S. Navy's Standard type battleships obsolete, just as HMS Dreadnought made the Royal Navy's pre-dreadnought battleships obsolescent and negated its advantage in numbers over other navies. This did not stop the U.S. Commander in Chief in European waters, Admiral William S. Sims, to argue for the redesigned vessels by pointing out that the Hood had already brought about the very revolution that the Board wished to suppress. Debate continued while the project remained suspended until May 1919, when the Board decided that the battlecruisers should be built as planned, except for a slightly slower version of Design B from C&R with increased protection for turrets, conning towers, magazines and communications. This amended version, labeled B3, was the final version of the Lexington battlecruiser design.