IJN Battleship Design A-115

Battleship Design A-115 was the first post Nagato battleship design of the IJN. It contains some novel changes compared to her predecessor, including closely arranged funnels likely to reduce the possibility of spotting the ship's direction armour wise a thinner but heavily, 25° inclined belt armour was introduced providing better protection at longer ranges then the vertical 305mm of the Nagato and which was consistent with the requirement of the Admiralty that all subsequent battleship type had to be stronger in one or more aspect then the previous one. But not only the armour was improved on this design but the speed too was increased considerably to 30knots or 56km/h over the already good speed of 26,5knots or 49km/h of the Nagatos. This of course required a longer sleek hull and bigger engines to achieve. The 25m extra length and half a meter wider beam allowed the install of almost 50% more (or in the case of the following design A-116 exactly 50% more) engine power into the hull to reach the desired speed. Despite the longer hull and more powerful engines the displacement was only risen by only 900tons showing how much weight can be saved by reducing the armour and incline it!

The design had the following characteristics:
Dimensions: 224,02 (pp) x 237,74 (wl) x 240,18 (oa) x 29,57 x 8,53 meters
Displacement: 34.700tons (standard)
Armour: 229mm Belt inclined at 25 degrees, 76mm Deck, 51mm at Machinery 76mm at Magazine Slopes
Engines: 113.000shp Gihon Steam Turbines, 4 shafts
Range: 10.200km at 30km/h (5.500nm at 16knots)
Speed: 56km/h (30knots)
Armaments:
4x2 410mm/45 Type 3 / 3rd Year Type Cannons,
20x1 140mm/50 Type 3 / 3rd Year Type Guns,
4x1 76mm/40 Type 3 / 3rd Year Type AA Guns,
4x1 53cm Above Water Torpedo Tubes

Data tables:
https://iiif.dl.itc.u-tokyo.ac.jp/repo/s/hiraga/document/d059f655-21b8-4530-8979-ce9ac0733c10#?c=0&m=0&s=0&cv=1&xywh=3593%2C85%2C2790%2C4678&r=270
https://iiif.dl.itc.u-tokyo.ac.jp/repo/s/hiraga/document/92cdfb52-21f7-4942-98e3-643167773975#?c=0&m=0&s=0&cv=3&xywh=1150%2C722%2C2053%2C3442&r=90