Chikuma class cruisers
Japan (1911) Chikuma, Yahagi, Hirado
The Japanese turbine Cruisers
The three cruisers described here are in the straight evolution of early prewar turbine cruisers, very fast and often recognized by their numerous funnels. They can be compared to the
Admiral Spaun,
Nino Bixio,
Magdeburg,
Chester,
C-class and "
Town" classes.
Chikuma participated in various operations in World War I and in the central and southern Pacific Ocean and was finally sank as a target in 1935. However, she was outlived by her sister ship Yahagi which was used in the Siberian Intervention and the opening stages of the Second Sino-Japanese War. Stricken on 1 April 1940 on the same day that her sister ship Hirado was also stricken. However, Hirado's hulk still served as floating barracks until 1943 whereas IJN Yahagi served for five more years as a training vessel at the Japanese Naval Academy at Eta Jima.
Conception of the Chikuma class cruisers
The Chikuma class cruisers were based on the sole Tone, a protected cruiser ordered as part of the 1907 Naval Expansion Program. The new Chikuma class was to be much larger with three ships built, the Chikuma, the Yahagi, and the Hirado. They would be laid down at Sasebo, Mitsubishi, and Kawasaki respectively, all being completed by 1912. They were unique for the time due to their monocaliber battery, an idea inspired by the Dreadnought but not adopted on other classes of ship until the British Dartmouth class. In addition to the main armament, two more 3-in guns (78 mm), were also added to the two existing, as well as torpedo tubes. The great novelty in the ships was their powerplant, as all three ships were equipped with turbines, which differed according to their yard: Yahagi had a Parsons turbine, and the two others, Curtis models. They were successful and all served for long quite long, with Yahagi and Hidaro even seeing the start of WW2.
Colorized photo of the Chikuma by Hirootoko Jr.
Design of the Chikuma class cruisers
Protection
The basic design of the Chikuma-class cruisers followed the latest Royal Navy Town class, but also integrated advances already present with the cruiser Tone. The Chikuma's class appearance was evident with its four smokestacks, unique in Japanese design (outside the later Sendai class). There has been confusion among authors about the level of protection of the Chikuma class, with the only real clarity being that it was similar to the Tone class. Although assimilated as a light cruiser, this was a protected cruiser without a proper armoured belt. Armour protection consisted of a protective deck ranging from 22 mm (0.87 in) beyond the central section (magazines and machinery), forward and aft, up to 57 mm (2.2 in) over the machinery space and magazines. The only other protected part was the Conning tower, at 102 mm (4.0 in) strong.
Propulsion
The Chikuma-class were the first Japanese cruisers fitted with turbines in the Imperial Japanese Navy. This solution inspired by the dreadnought helped achieve greater speeds, notably over that of the IJN Tone, which was given triple expansion steam engines. The 4100 tonnes Tone had 16 Miyabara boilers for 15,000 hp and 23 knots, whereas the Chikuma class were able to reach three more knots. Chikuma and Hirado both had Curtiss turbines, two shaft steam turbine engines and 16 Kampon boilers for a total of 22,500 hp (16,800 kW) versus 15,000 hp on the Tone.
This allowed these cruisers to reach a top speed of 26 knots (48 km/h; 30 mph), and in speed trials, this was confirmed by reaching 26.83 and 26.87 knots. IJN Yahagi had a Parsons-type turbine engine, achieving 27.14 knots during speed trials. Though the target of high speed was reached, this new technology provoked teething issues in early service, notably with material strength and fatigue, and maintenance issues.
Armament
The Chikuma armament was quite unique due to its single caliber main battery, that being eight Type 41 6 inch, 45-caliber naval guns. Two were placed fore and aft, and three in sponsons, on either side of the hull. In addition, these ships received four Quick Firing 12-pounder, 12 cwt naval guns, and two Lewis guns for anti-personnel/ torpedo boat duties. The 6-in originated from Armstrong Elswick and had a separate loading bagged charge of 22 kg (49 lb), with a shell weighing 45.4 kg (100 lb). They had a breech interrupted screw and could elevate -5° to +18° and traverse -150° to +150°, with a rate of fire of 5 rpm, a muzzle velocity of 825 m/s (2,710 ft/s), and a maximum firing range of 14.8 km (9.2 mi) at 18°.
The 12-pounder, 12 cwt guns dated back from a British Elswick design of 1894, had been modernized since, and were produced locally by Japan Steel Works. The qualification 12 cwt (for "hundredweight"). This was related to the weight of the barrel and breech. The 12-Pdr was also referred to locally as Type 41 3-inch (76.2 mm)/40 (weighing 0.6 tons, 510 kg), with an overall length of 10 ft 3 in (3.12 m), and barrel length alone of 10 ft (3 m).
It was breech-loaded, capable of 15 rounds per minute, with a muzzle velocity of 2,210 ft/s (670 m/s), and effective firing range of 11,750 yd (10,740 m) at 40° elevation. In addition, the cruisers were given three torpedo launchers fitted with 457 mm (18 in) torpedoes. After 1919, due to the growing AA threat, two 8 cm/40 3rd Year Type naval guns were added on anti-aircraft mounts. They were placed abaft the fourth funnel, in place of the former replacing two 12-pounders (in Hirado), or three for the Yahagi and Chikuma.
The 12-pounder, 12 cwt guns dated back from a British Elswick design of 1894, modernized since and produced locally by Japan Steel Works. The qualification 12 cwt (for "hundredweight"). This was related to the weight of the barrel and breech. The 12-Pdr also referred locally as Type 41 3-inch (76.2 mm)/40 weighted (0.6 tons, 510 kg), with an overall length of 10 ft 3 in (3.12 m), and barrel length alone of 10 ft (3 m). It was breech-loaded, capable of 15 rounds per minute, with a muzzle velocity of 2,210 ft/s (670 m/s), and effective firing range of 11,750 yd (10,740 m) at 40° elevation.
In addition, there cruisers were given with three torpedo launchers fitted with 457 mm (18 in) torpedoes and after 1919, due to the growing AA threat, two 8 cm/40 3rd Year Type naval gun were added, on anti-aircraft mounts. They were placed abaft the fourth funnel, in place of the former replacing two 12-pounders (in Hirado), or three for the Yahagi and Chikuma.

IJN Hirado in drydock Sydney in 1917 (Australian War Museum)
The Chikuma class in action
IJN Chikuma
IJN Chikuma was active in WWI and contributed to the Allied war effort under the Anglo-Japanese Alliance. She was part of the Japanese squadron which gave chanse to the German East Asia Squadron (under Admiral Von Spee) from August 1914. The Ibuki, Chikuma, and Nisshin chased the elusive squadron in the Indian Ocean as this was a real threat to shipping, especially as the German cruiser Emden had evaded contact and was known to be capturing and sinking merchant ships.
From December 1914 to January 1915, Chikuma and Yahagi patrolled off the coast of northern Queensland in Australia. From 26 March 1917, the British Admiralty pressed the deployment of the Chikuma and Hirado to Australia and New Zealand. They were assigned to the protection of shipping against possible German commerce raiders.
After the war, IJN Chikuma patrolled off China in 1921-1924. However, shortly afterward she was seen as obsolete and her combat use was to be reduced. She was assigned as a moored training ship at Yokosuka Naval District, after being moved to the reserves. IJN Chikuma was stricken from the list on 1 April 1931 but her hulk survived was as the Hai Kan No.3 target. She was sunk in that guise in 1935.
IJN Yahagi
IJN Yahagi fought in WWI under the Anglo-Japanese Alliance, and like her sister ship, she was deployed against the German East Asia Squadron. Hirado and Yahagi teamed up within the 2nd Southern Squadron (under Rear-Admiral Matsumura Tatsuo). The squadron patrolled the region around Sumatra, searching for the German cruiser Emden. From December 1914 to January 1915, the two cruisers also patrolled off the coast of northern Queensland, Australia, always in search of possible raiders that could threaten merchant traffic.
By 7 February 1917, this IJN squadron reformed as the First Special Squadron with the cruisers Yahagi, Tsushima, Suma, and Niitaka. They also integrated the Second Destroyer Flotilla. The composite squadron was based at Singapore under Rear Admiral Kozaburo Oguri. By 26 March 1917, the British Admiralty asked to deploy them to Australia and New Zealand to continue the protection of shipping against German raiders.
Yahagi and Suma were also deployed in the Indian Ocean in close cooperation with the British China Squadron. Yahagi patrolled the eastern coasts of Australia and New Zealand until October 1917 and was the last ship deployed to defend Australia and New Zealand. She only went back to Japan, on 21 October 1918. Its crew however was struck with influenza in December 1918 and she was in quarantine at Manila harbor, where during her 46 days of immobilization, 300 of her crew were taken ill while 48 died.
In 1919, Yahagi patrolled off the coast of eastern Russia, providing protection and support for supply convoys to Siberia during the Japanese Siberian Intervention against the Bolsheviks. She was then posted to protect the southern approaches to Japan. During that time, she alternated between Manila and Macau. From 1923 until 1937, IJN Yahagi patrolled the China sea, later replacing the Tone as a station ship on the Yangtze River.
With the war breaking in 1937, she was placed in reserve as a training ship at anchor. She would be stricken from the list on 1 April 1940. Her new affectation was as a target ship named Hai Kan No.12, posted at the Etajima Imperial Japanese Naval Academy. She became a barracks ship for submarine crews until 1943 and was scrapped on 8 July 1947.
IJN Hirado
In WW1, Hirado was active under the same Anglo-Japanese Alliance and deployed with the Japanese squadron against the German East Asia Squadron. IJN Hirado and Yahagi were part of the Allied 2nd Southern Squadron (Rear-Admiral Matsumura Tatsuo) patrolling around Sumatra, trying to catch the SMS Emden. On 26 March 1917, she was deployed with Chikuma and Yahagi to Australia and New Zealand, and later in the war, she supported the Japanese expedition against the Red Army off the east coast of Russia. The goal was to prevent any raids on supply convoys, in support of ground forces in Siberia. Admiral Osami Nagano took command of IJN Hirado in 1919-1920, followed by Captain Zengo Yoshida until December 1924.
Hirado was deployed in protection of the southern approaches to Japan, stationed at Manila and Macau. In 1932, she was ordered to the northern Chinese coast after the Manchurian Incident. She was based in the Ryojun Guard District (Kwantung Territory). Engines problems however had her frequently stationed in repair yards. She was unable however to take part in combat operations during the 1937 Sino-Japanese War.
Placed indeed in reserve by 1933 she became a training ship until she was stricken from the navy list on 1 April 1940. Afterward, she became IJN Hai Kan No.11, and was moored as a barracks ship at Etajima. She was later towed first to Kure, and then to Iwasaki in December 1943. She was scrapped after the war, starting in April 1947. Part of her hull now fills a section of the Iwakuni port breakwater.
Inded, placed indeed in reserve by 1933 she became a training ship until she was stricken from the navy list on 1 April 1940. She became afterwards IJN Hai Kan No.11, and was moored as a barracks ship at Etajima. She was later towed to Kure, and Iwasaki in December 1943. She was scrapped after the war, starting in April 1947. Part of the hull filled a section of the Iwakuni port breakwater.
Illustration of the Chikuma by the Author (1/750)
Specifications of the Chikuma class |
Displacement: 5,040 long tons (5,100 t) standard |
Dimensions: 144.8 m (475 ft 1 in), Beam 14.2 m (46 ft 7 in), Draught 5.1 m (16 ft 9 in) |
Propulsion: 2 shafts steam turbine, 16 Kampon boilers; 22,500 hp, 26 knots (30 mph; 48 km/h) radius 10,000 nmi (19,000 km) at 10 kn (12 mph; 19 km/h) |
Deck: 22-57 mm, CT 102 mm (4.0 in) |
Crew: 400 |
Armament: 8 × 6 in/45, 4 × 12 pdr, 2 × 7.7 mm, 3 × 457 mm TTs |
Sources/read more
https://www.globalsecurity.org/military/world/japan/chikuma-cl.htm
en.wikipedia.org/wiki/Chikuma-class_cruiser
Conway's all the world's battleships 1860-1905 & 1906-1921
http://www.navweaps.com/Weapons/WNJAP_6-45_EOC.php
Nishida, Ships of the Imperial Japanese Navy
Jentsura, Warships of the Imperial Japanese Navy; page 104-105
Evans, David C.; Peattie, Mark R. (1997). Kaigun: Strategy, Tactics, and Technology in the Imperial Japanese Navy, 1887-1941.
Howarth, Stephen (1983). The Fighting Ships of the Rising Sun: The Drama of the Imperial Japanese Navy, 1895-1945.
Jentsura, Hansgeorg (1976). Warships of the Imperial Japanese Navy, 1869-1945.
Schencking, J. Charles (2005). Making Waves: Politics, Propaganda, And The Emergence Of The Imperial Japanese Navy, 1868-1922.
Tucker, Spencer C (2005). Encyclopedia Of World War I: A Political, Social, And Military History.