If you have been in Discord you may have seen me do quite a few updates on a bunch of drawings of US battlecruisers. These are all part of the design study that would produce a number of designs for what would have been the first, and probably only class of battlecruisers in US history.
Some backstory is needed to fully understand the US mindset regarding battlecruisers. As far as they were concerned, they were to be regarded as armored cruisers, not fully fledged capital ships. This would keep them out of the line-of-battle. The US battlecruiser would be similar in mission to the German battlecruiers, namely as "battle scouts." Scout enemy position and/or destroy enemy scouts to deny the enemy the intel on your own fleet. Unlike German battlecruisers, most of the US battlecruisers were lightly armored to reduce weight, and size. They did have designs of battlecruisers that were heavily armored, but these were around 900-1000+ feet long, and had speed of under 30kts.
What would be known as the Lexington class came out of the need of scouts, but also a response to the Japanese Kongo class, thus a caliber of at least 14 inches was neccessary, though this would later increase to 16 inches. A hallmark of the Lexington class (as well as most American BC designs) was it's long, sleek hull to reach a top speed of 35kts. The hull as well as the armor belt, though usually quite thin, was very long, but also tall to increase the strength of the hull, and resist bending forces of waves. Creative ways of the placement of boiler rooms (placed above the waterline) and several funnels, often side-by-side was needed in order to propell ships of anything between 35k-45k tons to a speed of 35kts.
The first design that was approved for construction in 1915 was a 35500t ship with a waterline length of 745ft. Top speed was rather "modest" at 30kts. She would have a fairly conventional appearence with "only" three funnels. Armament consisted of 8x14"/45 caliber guns in four twin turrets, with one pair superfiring. The secondary armament consisted of 14x6"/53 caliber guns. Since there is no info on where these were to be placed, I put them in casemated amidships. The armor belt was 5" thick.
35500t Battlecruiser as designed in May, 1915:
1916 would see a major redesign of the battlecruiser, now to be six units, as opposed to four, and named Lexington. The hull was lengthened from 234m to 266,4m. Armament was kept at 14", but increased from 8 guns to 10, with two triples superfiring over two twins. Top speed was increased to 35kts, which neccessitated seven funnels, and some creative placemant of the boiler rooms. The secondary battery was increased from 14 guns to twenty, but caliber was reduced from 6" to 5". Construction of these ships actually started, but the 1917 entry of America into WW1 would see the delay of both the Lexington class, and the South Dakota class battleships.
33500t Battlecruiser as designed in June, 1916:
As WW1 raged on, there was plenty of time to look over the Lexington class, and address any faults, or updated any unwanted features. In 1918, a new design was put forward. With the same overall length, top speed was kept. Armament was changed from 10x14" guns, to the new 16"/50 caliber Mark 2 guns designed for the South Dakota class. Secondary battery was changed back to a 6" gun, and the number reduced back to 14. The armor belt was increased to 9" for better protection. New and more efficient boilers meant that the number of funnels could be reduced to five. Interestingly this design has a flush deck, with a single deck containing the seconday battery and the superstructure. Bigger guns, and additional increased the displacement to 45000t.
45000t Battlecruiser as designed in May, 1918:
Another redesign happened in 1919. The hull was brought back to the 1916 style of look, with a lowered quarter deck and the rest of the ship raised up one deck. Apart from this, very little changed. The armor belt was reduced back to 5", reducing the displacement to 35300t.
35300t Battlecruiser as designed in March, 1919:
After WW1, Britain and America started cooperating on naval matters. A design team was sent to each others navy. The Americans were quite interested in the new British battlecruiser HMS Hood, and the fact that it was stretching the boundary between battlecruiser and fast battleship. A number of elements from Hood was incorporated into the design of the Lexington. Features that were added was sloped armor belt, much better boilers, reducing the number of funnels from 5 smaller ones, down to two very large ones. The number if 6" guns was inceased from 14 to 16. The armor belt was increased from 5" to 7". More armor was placed on the turrets and barbettes. The displacement increased to 43500t, reducing top speed down to 33kts, which was considered an acceptable trade for more armor. Six ships of this type were to be built; USS Lexington, USS Constellation, USS Saratoga, USS Ranger, USS Constitution and USS Unites States with the hull numbers CC-01 through CC-06. All six alongside the South Dakota class battleship were cancelled in 1922 after the signing of the Washington Naval Treaty. The incomplete hulls of Lexington and Saratoga would see new life as they were converted into aircraft carriers.
43500t Battlecruiser as designed in 1919: (Final design)
Click on this link if you want to see all of them next to each other for the full evolution: