Number 13 pushed the fast-battleship idea beyond Amagi and Kii. The design paired 30-knot speed with the heavily subdivided internal structure expected of a battleship. A 13-inch waterline belt and five-inch deck gave it substantially more protection than Amagi. Its main battery comprised four twin 18-inch mountings. Those specifications explain why the design belongs with the battle line despite matching Amagi's speed.
Notable Point · 19:37-20:24
Number 13's 30-knot, 18-inch-gun design
The Number 13 design combined 30-knot speed, battleship subdivision, a 13-inch belt, a five-inch deck, and eight 18-inch guns.