Fuso-class battleships

The IJNS Fuso was the name-ship of the two-ship Fuso-class battleships of the Imperial Japanese Navy. (The two ships were named IJNS Fuso and IJNS Yamashiro.) As such, they were the first dreadnought battleships with a homogenous main armament designed and built in Japan*, and were based on the British-designed Kongo-class battlecruisers.

The name-ship of the Kongo-class was built in Britain by Vickers at Barrow-in-Furness and her three sisterships were built in Japan with British assistance. As a result, the designers of the Fuso-class based their design on that of the Kongo-class, and this becomes very apparent when one compares the two designs.

A side view of a Kongo-class battlecruiser.

A side view of a Fuso-class battleship.

The similarity between the two designs becomes even more obvious when one lays a side view of each design over the over.

A side view of a Fuso-class battleship overlaid over a side view of a Kongo-class battlecruiser.

A side view of a Kongo-class battlecruiser over a side view of a Fuso-class battleship.

It immediately becomes apparent how closely the two designs are to each other. The positions of the forward two superimposed turrets, bridge and foremast are very similar, as is the position of the aft-most turret and superstructure around the mainmast. The third turret on the Kong-class is also almost in exactly the same position as the fourth turret on the Fuso-class.

The obvious conclusion one can draw is that the Japanese designers took the basic design of the Kongo-class battlecruisers, reduced the size of the space required for the boilers and engines, and filled that freed-up space with two extra twin 14-inch gun turrets.

The following is a comparison of the two classes' characteristics as built, with the Kongo-class data being first and the Fuso-class data being shown in italics:

• Displacement: 26,952 tons/29,326 tons
• Dimensions:
• Length: 214.58m (704ft)/202.7m (665ft)
• Beam: 28.04m (92ft)/20.7m (94ft 2in)
• Draft: 8.22m (27ft)/8.7m (28ft 7in)
• Propulsion: 36 × Yarrow or Kanpon boilers providing steam to 2 sets of Parson or Brown-Curtis turbines (64,000 shp) driving four propellers/24 x Miyahara boilers providing steam to 2 sets of Brown-Curtis turbines (40,000 shp) driving four propellers)
• Speed: 27.5 knots/23 knots
• Range: 8,000 nautical miles at 14 knots/8,000 nautical miles at 14 knots
• Complement: 1,193/1,193
• Armament: 4 × twin 356 mm guns (Vickers 14-inch/45 gun);16 × single 152mm (6-inch) guns: 4 × single 76mm (3-inch) anti-aircraft guns; 8 × 533 mm (21-inch) torpedo tubes/6 × twin 356 mm guns (Vickers 14-inch/45 gun);16 × single 152mm (6-inch) guns: 5 × single 76mm (3-inch)anti-aircraft guns; 6 × 533 mm (21-inch) torpedo tube
• Armour:
• Waterline Belt: 203 to 76mm (8 to 3 inches)/305 to 102mm (12 to 4 inches)
• Deck: 25mm (1 inch)/51mm (2 inches)
• Gun turrets: 229 to 254 mm (9 to 10 inches)/279mm (11 inches)
• Barbettes: 254 to 76 mm (10 to 3 inches)/305mm (12 inches)
• Conning tower: 229 mm (9 inches)/351mm (13.8 inches)

The IJNS Yamashiro as built.

If the Washington Treaty had not been signed in 1922, it is likely that the Fuso-class would have been declared obsolete in the late 1920s and scrapped. However, it was decided to retain and modernise them, and this involved:

• Replacing their boilers (They now had 6 Kanpon boilers, which enabled the removal of the forward funnel).
• Replacing their engines (They now had 4 sets of Kanpon turbines (75,000 shp) which gave them a speed of 24.7 knots).
• Replacing the existing anti-aircraft guns with 4 x twin 127mm (5-inch) anti-aircraft guns.
• Removing the two 152mm (6-inch) guns closest to the bows.
• Increasing the deck armour to 114mm (4.5 inches).
• Their forward superstructures were enlarged with multiple platforms added to their tripod foremasts and additional space provided for two of the new twin 127mm (5-inch) anti-aircraft guns. The extended bridgework evolved into what was probably the most extreme example of a so-called pagoda mast.
• Their rear superstructures were rebuilt to accommodate mounts for two of the new twin 127mm (5-inch) anti-aircraft guns and additional fire-control directors.
• The hulls were given anti-torpedo bulges. This increased their beam to 31.1m (108ft 7in).and compensated for the increased topweight.
• The hulls were lengthened at the stern by 7.62m (25ft), which helped to offset the increase in beam.
• They were fitted with a catapult and collapsible crane so that they could operate three floatplanes.

The IJNS Fuso after her modernisation.

Despite these improvements, by 1941 the two ships were no longer regarded as suitable for frontline service. Their short-range anti-aircraft armament was increased during the war, and by 1944 they carried ninety-six 25mm (1-inch) automatic anti-aircraft guns. They spent much of the early part of the war at anchor in Hiroshima Bay acting as training ships, although they were involved as distant support during the Pearl Harbour attack and then operations against the Aleutian Islands.

The Fuso-class battleships at anchor.

As Japanese losses mounted, the two ships took on more active roles. In September 1944 they took Japanese Army reinforcements to Brunei before being assigned to Operation Shō-Gō., the attack on the United States Navy ships supporting the landings at Leyte They formed part of Admiral Nishimura's Southern Force and took part in the Battle of the Surigao Strait.

After coming under attack by nearly thirty aircraft from the USS Enterprise, during which both ships were damaged, they saw off a night-time attack by United States Navy PT Boats.

At 3.09am on 25th October 1944 the IJNS Fuso was hit by one or two torpedoes that were probably fired by the US destroyer USS Melvin. She immediately began to sink, and by 03.50 she had gone down, surrounded by a field of burning oil. Only ten of her crew survived.

At 3.52 the IJNS Yamashiro came under fire from Admiral Oldendorf's Task Group 77.2. She was repeatedly hit by 6-inch, 8-ich, 14-inch, and 16-inch shells during an engagement that lasted only eighteen minutes. She was set ablaze and suffered from one or more internal explosions. She was also hit by a torpedo that damaged her close to her starboard engine room. She then suffered a further four to six torpedo hits, and between 4.09am and 4.21sm she turned over sank. Like her sister, only ten of her crew survived.

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* Technically, the Kawachi-class battleships (IJNS Kawachi and IJNS Settsu) were the first dreadnought battleships designed and built in Japan, but their main armament was not uniform as they were armed with four 50-calibre 12-inch and eight 45-calibre 12-inch main guns in six turrets.

These turrets were arranged in a hexagonal layout, with a pair of 50-calibre 12-inch guns in fore and aft turrets and a pair of 45-calibre 12-inc guns in each of two turrets on both side of the ship.

A general arrangement drawing of the Kawachi-class battleships.

Interestingly, they were originally designed to have a uniform armament of twelve 45-calibre 12-inch guns, but when it was announced that the Royal Navy had introduced 50-calibre 12-inch guns into service, the Japanese Navy decided to do the same ... but were unable to afford to fit more that four per ship, hence the mixture of guns on these ships.