- Payne, Alan
- Naval technology
- None noted.
- RAN Ships
- None noted.
- December 1978 edition of the Naval Historical Review (all rights reserved)
On trials Kongo registered 27.54 knots with 78,257 shaft horse power and Tiger made 29.07 knots with 104,635 shaft horse power, a very large overload over her designed 85,000.
Kongo’s side armour was 8 inches thick, while Tiger’s was 9 inches. The total weight of armour and protection was 6,502 and 7,390 tons respectively. German battle cruisers had much thicker armour and in the Derfflinger class this was 12 inches. The increased armour was obtained by a much lighter hull and also much lighter machinery. The German battle cruisers had one very serious design fault, their subdivision was not as good as it should have been and this was later admitted by the Germans. It is believed that the subdivision of the Kongo was particularly good.
The main difference between the Kongo and the Tiger was that the Japanese ship had a main armament of eight 14-inch guns, while the British ship had 13.5-inch guns as fitted in all British Super Dreadnoughts up to that time. Originally the Kongo was intended to have ten 12-inch guns, but the idea was changed to 13.5-inch guns under very unusual circumstances. Thanks to the friendly relations caused by the Anglo- Japanese alliance, a Japanese naval attache in London managed to obtain very confidential information about the British 12-inch guns.
Firing trials of the 12-inch 50 calibre gun had proved that it had a larger spread of salvoes than the 13.5-inch 45 calibre gun which were scheduled for the Super Dreadnoughts. In fact the British 12-inch gun was not a particularly accurate gun, so the Japanese decided to go for the bigger gun. Both ships had a secondary armament of 6-inch guns.
The idea to adopt the 14-inch gun was a purely Japanese affair and as no British 14- inch gun existed at the time, it was a most extraordinary decision. The Japanese were forced to order Vickers to manufacture a prototype and this was tested in March 1911. Soon after the firing trials of the new gun, the United States Navy made public that it had decided to adopt 14-inch guns for their new battleships Texas and New York. The decision to adopt the new 14-inch guns when there was a perfectly satisfactory 13.5-inch gun available was very obviously due to the Japanese wishing to go one better than the British.
The Japanese claim that the basic design of the Kongo was executed by the Japanese Naval Construction Department, based on the Vickers’ draft plan of an improved Lion class. There can be no doubt that this is completely untrue, because the Japanese were at this period hopelessly behind in the design and construction of large battleships and battle cruisers. The best battle cruiser of pre-war design was the work of Sir George Thurston and like all good designs the ships were later capable of great improvement by reconstruction with much lighter and more powerful machinery.
Sir Philip Watts, the Director of Naval Construction responsible for the design of the Tiger, was not very impressed with the design of the mighty Hood of 41,000 tons. He claimed that by using small tube boilers as in the Hood he could have produced a battle cruiser as good as the Hood for only 33,000 tons. As the term ‘standard displacement’ did not exist in 1920 he was referring to normal displacement with about a thousand tons of fuel included. Sir Philip was being rather over optimistic perhaps, so we can comfortably increase the figure to around 34,000 tons standard displacement – a saving of 7,000 tons.
Kongo was actually reconstructed twice and after the first the speed was reduced to 25.9 knots. On her trials in 1913 Kongo had achieved 27.54 knots with 78,275 shp. But as her designed horsepower was only 64,000 shp she had not achieved her designed speed at the designed horsepower. During the first reconstruction Kongo had about four thousand tons of armour added and was reboilered.
Kongo began her second reconstruction in 1935 when she was converted to complete oil firing and had new machinery with a horsepower more than doubled at 136,000 shp. The ship was lengthened 25 feet aft and the speed increased to 30.5 knots. On completion in 1937 Kongo was rated as a fast battleship and was then probably the fastest battle ship afloat, being faster than the Hood. The standard displacement had now gone up to 31,720 tons, over five thousand tons more than her designed displacement.
All four ships of the class were sunk in the Pacific during the war, the Kongo being sunk by the United States submarine Sealion on 21st November 1944 and at the time was the oldest fully operational battleship in the world. The four high speed battleships of the Kongo class comprised the Third Battleship Division during the war and operated with the carrier task forces in the Pacific war. The other three ships were the Kirishima, Haruna and the Hiel