IJN Kaga Class Battleship

Part of the 8-8 construction programme, this was the final design accepted for construction as the follow up battleship class to the Nagatos and named Kaga class though Tosa was laid down earlier and hence often called Tosa in a number of sources. The class could be seen as a 5 turreted lengthened and improved version of Nagato incorporated many changes into the design but the flush deck design, 5th turret, one funnel and armour layout shows otherwise. The improvement in engine technologies during WW1 resulted in a 15% increase in shp to mount in around the same space as on Nagato, the armour belt while was thinner of only 280mm it was inclined hence providing better protection over longer ranges. Firepower seems to be the accepted standard for Post WW1 IJN as not just Kaga/Tosa, but the Amagi and Kii classes too would wield the same 10 gun broadsides in 5 twin turrets.
Often the design number A-127 was associated with the Tosa / Kaga class but from the Hiraga archives it is evident that 127 and Kaga are two different designs. Indeed A-127 was used as the very basis for the final Kaga class there are a number of differences between the two, Kaga/Tosa having oval shaped funnel, 3m longer hull and differently arranged torpedo tubes apart form a number of minor structural differences.

The design had the following characteristics:
Dimensions: 217,93 (pp) x 231,65 (wl) x 234,1 (oa) x 30,5 x 9,4 meters
Displacement: 39.900tons (standard), 44.200 (full load)
Armour: 280mm Belt inclined to 15 degrees, 102mm Deck, 76mm Slopes
Engines: 91.000shp Curtis Steam Turbines, 4 shafts
Range: 12.000km at 30km/h (5.500nm at 16knots)
Speed: 49km/h (26,5knots)
Armaments:
5x2 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 61cm Above Water and 4x1 Underwater Torpedo Tubes

Official drawings:
https://iiif.dl.itc.u-tokyo.ac.jp/repo/s/hiraga/document/965fed86-86b2-43f7-b746-5d78c43888d1#?c=0&m=0&s=0&cv=0&xywh=-1118%2C-274%2C9179%2C5475
https://iiif.dl.itc.u-tokyo.ac.jp/repo/s/hiraga/document/d7a05db2-51dc-4799-9653-dbe86d1e051a#?c=0&m=0&s=0&cv=0&xywh=-659%2C0%2C8261%2C4927

Data table with connection of a proto-Kii design:
https://iiif.dl.itc.u-tokyo.ac.jp/repo/s/hiraga/document/41531699-0716-45b3-8ee9-8b607dd4ade5#?c=0&m=0&s=0&cv=0&xywh=1721%2C659%2C2561%2C1528