Tsukuba class cruiser
Encyclopedia
The two were battlecruiser
s operated by the Imperial Japanese Navy
. They participated in numerous actions during the World War I
.
, spurred on by the unexpected loss of the Yashima
to a naval mine
in the early stages of the war. As the new class was the largest design yet attempted independently by Japanese naval shipyards, contemporary American military observers were surprised (and concerned) at the rapid pace of construction, and that Japan had learned to build such large and powerful warship
s so quickly. However, with rapid advances in naval technology and with increasing budget constraints on the Imperial Japanese Navy in the period immediately after the end of the Russo-Japanese War, the project was scaled back, and in the end, only Tsukuba and Ikoma were built out of what was intended to be a class of six vessels.
's HMS Invincible
. On the other hand, American Tennessee class cruiser
of 1903 mounted 10" guns, which previously had been considered battleship guns (such as Russian Peresviet class battleship; USS Maine
had been designed and built as a battleship, too). The design intent of Tsukuba class was to retain the speed and protection of the latest version armoured cruisers, but mounting battleship-caliber primary armament.
on the Tsukuba-class were four Type 41 12-inch 45 caliber naval guns, mounted in twin gun turret
s to the fore and aft, along the centerline of the vessel. These were made by Japan Steel Works
under licence from Armstrong Whitworth
, and were the first large-caliber weapons manufactured in Japan. Secondary armament
was provided by twelve Type 41 6 inch 40 caliber naval guns and twelve Type 41 4.7 inch 40 caliber naval guns.
Commissioned from Kure Naval Arsenal
in 1907, Tsukuba served patrol duty during World War I
primarily in the Pacific Ocean
and in Southeast Asia
. On 14 January 1917, Tsukuba exploded while in port at Yokosuka
, and sank with a loss of 305 men.
Ikoma
Ikoma circumnavigated the southern hemisphere
of the globe soon after commissioning from Kure Naval Arsenal
in 1908. Ikoma served patrol duty during World War I
primarily in the Pacific Ocean
and in Southeast Asia
. Ikoma was a victim of the Washington Naval Agreement of 1923.
Battlecruiser
Battlecruisers were large capital ships built in the first half of the 20th century. They were developed in the first decade of the century as the successor to the armoured cruiser, but their evolution was more closely linked to that of the dreadnought battleship...
s operated by the Imperial Japanese Navy
Imperial Japanese Navy
The Imperial Japanese Navy was the navy of the Empire of Japan from 1869 until 1947, when it was dissolved following Japan's constitutional renunciation of the use of force as a means of settling international disputes...
. They participated in numerous actions during the World War I
World War I
World War I , which was predominantly called the World War or the Great War from its occurrence until 1939, and the First World War or World War I thereafter, was a major war centred in Europe that began on 28 July 1914 and lasted until 11 November 1918...
.
Background
Construction of the Tsukuba class armoured cruisers was ordered under the 1904 Emergency Fleet Replenishment Budget of the Russo-Japanese WarRusso-Japanese War
The Russo-Japanese War was "the first great war of the 20th century." It grew out of rival imperial ambitions of the Russian Empire and Japanese Empire over Manchuria and Korea...
, spurred on by the unexpected loss of the Yashima
Japanese battleship Yashima
|-External links:** The New York Times, June 2, 1905....
to a naval mine
Naval mine
A naval mine is a self-contained explosive device placed in water to destroy surface ships or submarines. Unlike depth charges, mines are deposited and left to wait until they are triggered by the approach of, or contact with, an enemy vessel...
in the early stages of the war. As the new class was the largest design yet attempted independently by Japanese naval shipyards, contemporary American military observers were surprised (and concerned) at the rapid pace of construction, and that Japan had learned to build such large and powerful warship
Capital ship
The capital ships of a navy are its most important warships; they generally possess the heaviest firepower and armor and are traditionally much larger than other naval vessels...
s so quickly. However, with rapid advances in naval technology and with increasing budget constraints on the Imperial Japanese Navy in the period immediately after the end of the Russo-Japanese War, the project was scaled back, and in the end, only Tsukuba and Ikoma were built out of what was intended to be a class of six vessels.
Design
The Tsukuba class cruisers were ordered and laid down before British Royal NavyRoyal Navy
The Royal Navy is the naval warfare service branch of the British Armed Forces. Founded in the 16th century, it is the oldest service branch and is known as the Senior Service...
's HMS Invincible
HMS Invincible (1907)
HMS Invincible was a battlecruiser of the British Royal Navy, the lead ship of her class of three, and the first battlecruiser to be built by any country in the world. She participated in the Battle of Heligoland Bight in a minor role as she was the oldest and slowest of the British battlecruisers...
. On the other hand, American Tennessee class cruiser
Tennessee class cruiser
The Tennessee-class armored cruisers were four ships of the US Navy built between 1903–1906. The first pair were authorized in 1902 and the second in 1904...
of 1903 mounted 10" guns, which previously had been considered battleship guns (such as Russian Peresviet class battleship; USS Maine
USS Maine
Four ships of the United States Navy have borne the name USS Maine, named for the 23rd state.*The first , was a second-class pre-dreadnought battleship whose sinking by an explosion, either internal or by a mine, on February 15, 1898 at 9:40 p.m...
had been designed and built as a battleship, too). The design intent of Tsukuba class was to retain the speed and protection of the latest version armoured cruisers, but mounting battleship-caliber primary armament.
Armament
The main batteryMain battery
Generally used only in the terms of naval warfare, the main battery is the primary weapon around which a ship was designed. "Battery" is in itself a common term in the military science of artillery. For example, the United States Navy battleship USS Washington had a main battery of nine guns...
on the Tsukuba-class were four Type 41 12-inch 45 caliber naval guns, mounted in twin gun turret
Gun turret
A gun turret is a weapon mount that protects the crew or mechanism of a projectile-firing weapon and at the same time lets the weapon be aimed and fired in many directions.The turret is also a rotating weapon platform...
s to the fore and aft, along the centerline of the vessel. These were made by Japan Steel Works
Japan Steel Works
is a steel manufacturer founded in Muroran, Hokkaidō, Japan in 1907.-History:Japan Steel Works was set up with investment from British firms Vickers and Armstrong Whitworth. During World War II, they manufactured what was then the world's largest gun barrel to be fitted on the battleship Yamato...
under licence from Armstrong Whitworth
Armstrong Whitworth
Sir W G Armstrong Whitworth & Co Ltd was a major British manufacturing company of the early years of the 20th century. Headquartered in Elswick, Newcastle upon Tyne, Armstrong Whitworth engaged in the construction of armaments, ships, locomotives, automobiles, and aircraft.-History:In 1847,...
, and were the first large-caliber weapons manufactured in Japan. Secondary armament
Battleship secondary armament
The secondary armament of a capital ship are smaller, faster-firing weapons that are typically effective at a shorter range than the main weapons...
was provided by twelve Type 41 6 inch 40 caliber naval guns and twelve Type 41 4.7 inch 40 caliber naval guns.
Propulsion
Propulsion was by two vertical triple expansion steam reciprocating engines, two-shafts, with twenty boilers, yielding 20500 shp design speed of 20.5 knots (40 km/h) and a range of 5000 nautical miles (9,260 km) @ 14 knots (27 km/h). During speed trials in Hiroshima Bay prior to commissioning, Ikoma attained a top speed of 21.75 knots (43 km/h)Ships in class
TsukubaJapanese cruiser Tsukuba
|-External links:**...
Commissioned from Kure Naval Arsenal
Kure Naval Arsenal
was one of four principal naval shipyards owned and operated by the Imperial Japanese Navy. -History:The Kure Naval District was established at Kure, Hiroshima in 1889, as the second of the naval districts responsible for the defense of the Japanese home islands along with the establishment of the...
in 1907, Tsukuba served patrol duty during World War I
World War I
World War I , which was predominantly called the World War or the Great War from its occurrence until 1939, and the First World War or World War I thereafter, was a major war centred in Europe that began on 28 July 1914 and lasted until 11 November 1918...
primarily in the Pacific Ocean
Pacific Ocean
The Pacific Ocean is the largest of the Earth's oceanic divisions. It extends from the Arctic in the north to the Southern Ocean in the south, bounded by Asia and Australia in the west, and the Americas in the east.At 165.2 million square kilometres in area, this largest division of the World...
and in Southeast Asia
Southeast Asia
Southeast Asia, South-East Asia, South East Asia or Southeastern Asia is a subregion of Asia, consisting of the countries that are geographically south of China, east of India, west of New Guinea and north of Australia. The region lies on the intersection of geological plates, with heavy seismic...
. On 14 January 1917, Tsukuba exploded while in port at Yokosuka
Yokosuka, Kanagawa
is a city located in Kanagawa, Japan. As of 2010, the city had an estimated population of 419,067 and a population density of 4,160 people per km². It covered an area of 100.62 km²...
, and sank with a loss of 305 men.
Ikoma
Japanese cruiser Ikoma
was the second vessel of the two-ship Tsukuba-class of heavy cruisers in the Imperial Japanese Navy. Ikoma was named after Mount Ikoma located on the border of Osaka and Nara prefecture...
Ikoma circumnavigated the southern hemisphere
Southern Hemisphere
The Southern Hemisphere is the part of Earth that lies south of the equator. The word hemisphere literally means 'half ball' or "half sphere"...
of the globe soon after commissioning from Kure Naval Arsenal
Kure Naval Arsenal
was one of four principal naval shipyards owned and operated by the Imperial Japanese Navy. -History:The Kure Naval District was established at Kure, Hiroshima in 1889, as the second of the naval districts responsible for the defense of the Japanese home islands along with the establishment of the...
in 1908. Ikoma served patrol duty during World War I
World War I
World War I , which was predominantly called the World War or the Great War from its occurrence until 1939, and the First World War or World War I thereafter, was a major war centred in Europe that began on 28 July 1914 and lasted until 11 November 1918...
primarily in the Pacific Ocean
Pacific Ocean
The Pacific Ocean is the largest of the Earth's oceanic divisions. It extends from the Arctic in the north to the Southern Ocean in the south, bounded by Asia and Australia in the west, and the Americas in the east.At 165.2 million square kilometres in area, this largest division of the World...
and in Southeast Asia
Southeast Asia
Southeast Asia, South-East Asia, South East Asia or Southeastern Asia is a subregion of Asia, consisting of the countries that are geographically south of China, east of India, west of New Guinea and north of Australia. The region lies on the intersection of geological plates, with heavy seismic...
. Ikoma was a victim of the Washington Naval Agreement of 1923.