Number 13-class battleship

Right elevation line drawing of the design for the Number 13 class
Class overview
Builders	Kure Naval Arsenal Yokosuka Naval Arsenal Kawasaki Shipyard, Kobe Mitsubishi Shipyard, Nagasaki
Operators	Imperial Japanese Navy
Preceded by	Kii class
Succeeded by	Yamato class
Planned	4
Cancelled	4
General characteristics
Type	Fast battleship
Displacement	47,500 t (46,700 long tons) (normal)
Length	274.4 m (900 ft 3 in)
Beam	30.8 m (101 ft 1 in)
Draft	9.8 m (32 ft 2 in)
Installed power	22 × water-tube boilers 150,000 shp (110,000 kW)
Propulsion	4 shafts; 4 × geared steam turbines
Speed	30 knots (56 km/h; 35 mph)
Armament	4 × twin 46 cm (18 in) guns [1] 16 × single 14 cm (5.5 in) guns 8 × single 12 cm (4.7 in) AA guns 8 × 61 cm (24 in) torpedo tubes
Armor	Waterline belt: 330 mm (13 in) Deck: 127 mm (5 in)

The Number 13-class battleship was a planned class of four fast battleships to be built for the Imperial Japanese Navy (IJN) during the 1920s. The ships never received any names, being known only as Numbers 13–16. They were intended to reinforce Japan's "eight-eight fleet" of eight battleships and eight battlecruisers after the United States announced a major naval construction program in 1919. The Number 13 class was designed to be superior to all other existing battleships, planned or building. After the signing of the Washington Naval Treaty in 1922, they were cancelled in November 1923 before construction could begin.