IJN Azuma (1899)

Nihhon Kaigun (1900-1941): Armoured Cruiser (Sōkō jun’yōkan)

Azuma (吾妻 or Adzuma) was an Imperial Japanese Navy armored cruiser ordered from France in 1897, as Japan lacked the industrial capacity matching her naval expansion plan after the Sino-Japanese war and in preparation for future conflicts in the region, notably against a rearming Imperial Russia. She thus took part in the naval battles of the Russo-Japanese War of 1904–05, damaged at the Battle off Ulsan and Battle of Tsushima. In the interwar, she became a TS, and started training cruises in 1912 and during World War I, albeit never formally reclassified as such, she continued in her role from 1921 until disarmed and hulked in 1941. Still around in the summer of 1945 she was badly damaged in a TF 38 raid in 1945, and scrapped in 1946.

Azuma as completed, just after receiving her artillery, in Portsmouth before departing for Japan (irootoko Jr, cropped)

Development

The 1896 Naval Expansion Plan, two years after the Sino-Japanese war (1894) called for four armoured cruisers, in addition to four more battleships (the “4-4” plan) but since Japanese shipyards at the time were few and lack capacity, they were all ordered from overseas shipyards. Later but seeing the own Russian shipbuilding program ramping up, the IJN believed the original plan would not be sufficient. However, Budgetary constraints prevented an order for more battleships so the IJN decided to make due with more armoured cruisers and raised the plan from four to six.

One argument from this swap to armoured cruiser was the belief in the resistance of the brand-new Krupp cemented armour. They were not the only ones to believe this. There was a new line of thinking in general about a new generation of heavily-armed, well protected cruisers capable of taking part in the line of battle. The revised plan called “6-6 Fleet” called for the four ships to be built by Armstrong Whitworth, but since the latter already worked at full capacity, the remainder two could only be built in Germany and France, with Italy as an option.

One core concern however was ammunition compatibility. So the IJN required all builders to integrate the same British (soon to be patented and made in Japan) for all. The IJN provided only a sketch design and specifications, so each builder was free to interpret the details. Both Germany and France came out with very different end products, as expected. Still, they had to comply to a baseline of specifications under penalty. However specifications made them more suitable for commerce raiding and for overseas colonial deployments colonies or to protect the Imperial trade routes. Azuma also had the role of a fleet scout when required in wartime, this time taking part in the battle line. In her case, Azuma was ordered on 12 October 1897 from Ateliers et Chantiers de la Loire, Saint-Nazaire, France (Atlantic Coast).

Design

Hull and general Layout

Azuma measured 137.9 meters (452 ft 5 in) long overall for 131.56 meters (431 ft 8 in) between perpendiculars. Her beam was 17.74 meters (58 ft 2 in) and average draft was 7.18 meters (23 ft 7 in). Her displacement was 9,278 metric tons (9,131 long tons) on normal load, up to 9,953 metric tons (9,796 long tons) deeply loaded. Furthermore, her metacentric height was 0.85 meters (2 ft 9 in). She also had a double bottom.
For her overall outlook, she indeed looked “French” although her ram bow was reasonably long, more comparable to British designs, and she had limited to no tumble home. The most “French” espect was perhaps her three two-section funnels, unheavenly placed. However, she lacked the typical French military heavy masts for more moderate pole masts with spotting tops. Her fire control was also British. The remainder was consistent with other designs, but she sported mostly turrets on the main deck, and few hull casemates. As completed she carried ten boats of all types, yawls, cutters, barges, and whalers for a crew that consisted of 670 officers and enlisted men.

Powerplant

Azuma had two 4-cylinder triple-expansion steam engines provided by St. Nazaire, on two propellers and the steam came from 24 Belleville water tube boilers. This powerplant was rated at a total of 18,000 indicated horsepower (13,000 kW) in order to reach their designed speed of 21 knots (39 km/h; 24 mph). Trial speed is unknown. Despite being 400t lighter than British-built cruisers, she was no faster. She carried 1,200 metric tons (1,200 long tons; 1,300 short tons) of coal, enough to sail 7,000 nautical miles (13,000 km; 8,100 mi) at 10 knots (19 km/h; 12 mph), also as designed. In 1930 the boilers were replaced by six modern Yarrow oil/coal-burning models, but engine power fell to 9400 hp, top speed down to 16kts.

Protection

Her protection was made in KC (Krupp Cemented Armour) for all important armour, and standard French armour steel for the remainder.
The main difference, compared to British Cruisers, was the lack of an aft armoured bulkhead.
Details of the armour:
Waterline belt: 89–178 mm (3.5–7.0 in) 64 m long x 2.1 m tall between barbette bulkheads, 89mm outside.
Upper Battery Belt: 127 mm (5 inches) also on 64 x 2.1 meters.
Deck: 63 mm (2.5 in). Turtle back. Connected to the lower belt by 76 mm (3 in) slopes. 63-51 mm ends.
Gun Turrets: 160 mm (6.3 in).
Barbettes, main and secondary: 152 mm (6 in).
Casemates: 51–152 mm (2.0–6.0 in)
Conning tower: 356 mm (14.0 in) and 76mm (3 in) roof.
Transverse Bulkheads: 76 mm (3.0 in)
Amidship 6-in Guns protection: 51 mm (2 in) armour.
Fore Torpedo Room: 152mm (8 in) armour.
ASW Protection: Subdivision into 213 watertight compartments.

Armament

20.3 cm/45 Type 41 naval guns

The standard armament adopted for all the 6-6 plan was the same, the armoured cruisers were given four Armstrong Whitworth-built 45-caliber eight-inch guns. They came out in two twin turrets fore and aft. They were electrically operated for a 130° rotation left and right, max elevation to +30°, max depressed to −5°. There were already 65 ready rounds in the turrets, the remainder being reloaded through doors in the turret floor, with an electric winch to hoist these from the shell room below. The grand total was 320 eight-inch shells. They were manually loaded at fixed angle, so for a rate of fire about 1.2 rounds per minute. These were 113.5-kilogram (250 lb) armour-piercing (AP) shelled capable of a muzzle velocity of 760 meters per second (2,500 ft/s) and max range of 18,000 meters (20,000 yd).

QF 6 inch /40 naval guns

The secondary armament comprised twelve Elswick Ordnance Company “Pattern Z” quick-firing (QF) and 40-caliber 6-inch (152 mm) guns. Four were not mounted in armoured casemates on the main deck, the remainder shielded on the upper deck. They fired a 45.4 kilograms (100 lb) AP shell at a muzzle velocity of 700 meters per second (2,300 ft/s). 150 rounds were provided for each gun, making for a total of 1800 shells total.

QF 12-pounder 12 cwt naval guns

Yakumo had in reinforcement for close ranges against destroyers a dozen of 40-caliber Quick Firing 12-pounder 12-cwt guns, calibre 76 mm or 3 inches. They fired a 5.7-kilogram (12.5 lb) shell at a muzzle velocity of 719 meters per second (2,359 ft/s). Unitary shells for quick reload, range 11,750 yd (10,740 m) at 40° elevation. Four were mounted in casemates on the battery deck, and the remainder located either along the weather deck bulwarks over the secondary guns casemates, and four each on the forward and aft structures.

QF 3-pounder Hotchkiss guns

She rounded her defensive armament with eight QF 2.5-pounder Yamauchi guns for close-range defence. Similar to the standard Hotchkiss light, one man pintle mounted guns seen on other vessels. Location is unclear. They fired a 47 mm Fixed QF 47 × 376 mm R 3 kg (6.6 lb) round at 30 rpm to 571 m/s (1,870 ft/s) and 5.9 km (3.7 mi) max at +20°.

457 mm (18 inches) Whitehead Torpedo Tubes

Sae model as the standard 18-in Whitehead Mark I.

Modifications

1924:She lost four 3-in/40 guns and four 3-pdr or 47mm/40, and three 18-in (450mm) TTs but gained a single 3-in(76pp)/40 Type 3 AA gun.
1930: She lost four 6-in(152mm)/40 guns and four more 3-in(76mm)/40, three 3-pdr (47mm)/40, and her last two 18-in TTs.

Author’s profile

⚙ Azuma 1899 specifications
Displacement	9,278 t (9,131 long tons)
Dimensions	137.9 x 17.74 x 7.18m (452 ft 5 in x 58 ft 2 in x 23 ft 7 in)
Propulsion	2 shafts VTE engines, 24 Belleville boilers, 18,000 ihp (13,000 kW)
Speed	21 knots (39 km/h; 24 mph)
Range	7,000 nmi (13,000 km; 8,100 mi) at 10 knots (19 km/h; 12 mph)
Armament	2×2 20.3 cm/45, 12× QF 152mm/40, 12× QF 12-pdr 12 cwt, 8× QF 3-pdr Hotchkiss, 5× 457 mm TTs
Protection	Belt 89–178 mm, Deck 63 mm, turret 160 mm, Barbette 152 mm, Casemate 51–152 mm, CT 356 mm, Bulkhead 127 mm
Crew	670

Gallery

Azuma, Flickr.

Career of IJN Azuma

The contract was signed on 12 October 1897 with Ateliers et Chantiers de la Loire, she was laid down on 1 February 1898, launched on 24 June 1898 and completed on 29 July 1900, accepted. She left for Japan the next day, making underway further sea trials and shake down until she arrived in Yokosuka on 29 October. Captain Fujii Kōichi was in command on February 1904, and by January 1905, Captain Murakami Kakuichi.
She was in 2nd Division, 2nd Fleet and took part in the Battle of Port Arthur on 9 February 1904 under VADM Tōgō Heihachirō and the Combined Fleet. In the ensuing battle, the cruisers were ordered to split fire between the fortifications with their main guns and deal with Russian cruisers with their secondaries, doing little damage while taking some punishment, not the case for Azuma.
In March, Vice Admiral Kamimura Hikonojō was sent to join the 2nd Division north for a diversion off Vladivostok. The cruisers, inc. Azuma, bombarded the harbour and defence on 6 March. Back to Japan the 2nd Division returned, escorting troopships with the Imperial Guards Division to Korea and then join the blockade of Port Arthur. In mid-April she was ordered to the Sea of Japan and defend the Korea Strait, preventing a sortie from the Vladivostok Independent Cruiser Squadron (Rear Admiral Karl Jessen), preventing it to unite with the Pacific Squadron. On the 24th in heavy fog, Azuma narrowly escaped collision with an other cruiser. She later helped laying minefields before proceeding to Wonsan.
The Russian squadron went though and attack Japanese transport south of Okinoshima on 15 June, thanks to heavy rain and fog. For their 30 June sortie, VADM Kamimura managed to catch them, this time near Okinoshima while darkness fell so the Russsians disengaged after a short engagement. On 17 July, the Russians attempts a sortie of the eastern coast of Japan to draw out Kamimura’s cruisers down to the Yellow Sea. They passed through the Tsugaru Strait two days later and capturing Japanese transports returning to Japan. When they showed up in Tokyo Bay on the 24th, the Naval General Staff to order Kamimura to sail to Cape Toi Misaki in Kyūshū, fearing a circumnavigation before reaching Port Arthur. Next hos force was in Kii Channel, Tokyo Bay on the 28th, then ordered back to Tsushima on the 30th, learning later Jesse, passed through the Tsugaru Strait and reached Vladivostok on 1 August.

On 10 August, the Russians trapped in Port Arthur attempted a breakout to Vladivostok, which started the Battle of the Yellow Sea. Jessen was ordered to meet them, but this was delayed. Yet his cruisers, Rossia, Gromoboi, and Rurik, raised steam and he sortied on 13 August, reaching by dawn Tsushima, but turned back when failing to see the Port Arthur squadron. Soon he fell on Kamimura’s squadron (Iwate, Izumo, Tokiwa, Azuma) which took positions during the night placing them astride the Russians back to Vladivostok.
Jessen ordered a northeast turned when he spotted them at 05:00 ad both lines ended on a converging course, fire started at 05:23 from 8,500 meters (9,300 yd). Rurik, last in line was the first to suffer and started to fall astern. Jessen turned southeast to open range, but this blinded the Russian gunners facing the rising sun. At 06:00 he made a new 180° starboard turn to reach the Korean coast and meet Rurik but Kamimura followed suit at 06:10, but turned to port, opening range. Azuma however started to develop engine issues, forcing the whole squadron to slow down, but the engagement resumed at 06:24. Rurik was hit thrice in the stern, lost her steering compartment, being forced to steer with the engines, wearing them down.

Her speed fell, her steering jammed to port at 06:40 when Jessen made another 180° to interpose his ships and save Rurik, but the latter turned to starboard, increased speed, passed between Jessen and the Japanese. Kamimura turned 180° and both lines new headed southeast. Jessen made yet another 180° so to be on opposing course and again at 07:45, all to support Rurik, while Rossia had been hit several times and was on fire for about 20 min. Kamimura circled Rurik, to finish her off s the remaining cruisers sailed north to Vladivostok, then turned again at 08:15, ordering Rurik to make her own way back to Vladivostok, trying to lure out the Japanese, then north again at 18 knots.
Kamimura’s Naniwa and Takachiho arrived from the south, ordered to finish off Rurik while himself was to pursue Jessen. This went on for one hour and a half, they took hits enough for their speed down to 15 knots. Azuma however, had troubled with her engines and dropped the chase, replaced by Tokiwa. The engagement fell to 5,000 meters (5,500 yd) but at 10:00, Kamimura’s gunnery officer reported Izumo had spent already 3/4 ammunition. So she was ordered to returned to the Tsushima Strait and possibly finish off Rurik, but in between the latter already had been sunk by Naniwa and Takachiho, down to 3,000 meters (3,300 yd). Kamimura never received the message. Gromoboi and Rossia reached Vladivostok and started repairs. Azuma only suffered 8 wounded in the battle.

On 30 December, Azuma and Asama were ordered to patrol Tsugaru Strait to block the path from Vladivostok. In mid-February, Azuma was relieved by Iwate and returned to Japan for a refit.
On 27 May, the relief “2nd pacific fleet” from the Baltic Sea was known to arrive soon, so Yakumo, still part of Kamimura’s 2nd Division, 2nd Fleet was in search for them, in poor visibility and limited radio reception. Tōgō wanted the 2nd Division to shadow the fleet of Vice Admiral Zinovy Rozhestvensky from 11:30. Kamimura closed to 8,000 meters (8,700 yd) before meeting Tōgō’s battleships, Azuma being second out of the line of six. Fore started at 14:10 and, concentrating on the Knyaz Suvorov. At 14:50, Azuuma took a 12-inch (305 mm) shell that knocked out her aft right 8-inch gun. By 15:00, Knyaz Suvorov appeared out of the mist at 15:35 from 2,000 meters (6,600 ft), facing Azuma and Yakumo, which both fired torpedoes but missed.
After 17:30, Kamimura was in pursuit of fleeing Russian cruisers, leaving Tōgō behind until recalled around 18:03, spotting the rear of the Russian battleline at 18:30, opening fire from 8,000–9,000 meters (8,700–9,800 yd) until 19:30. They reached Tōgō at 20:08. Next morning, the surviving Russian ships were spotted again at 10:30, but the Russians could not fire as they remained beyond range of the Japanese, which out-ranged them. Rear Admiral Nikolai Nebogatov decided to surrender. Azuma in total was hit 7 times, including 12 inch, and four 6 inches, four 3-in with little damage, a 6-inch and a 12-pounder gun mount.
On 14 June, Azuma, Yakumo, Nisshin and Kasuga were assigned of the 3rd Fleet (Vice Admiral Kataoka Shichirō) to take part in the capture of Sakhalin in July.

On 20 April 1912 Azuma was allocated to the training squadron already. She made a few long-distance oceanic cruises with officers and cadets in link with the Naval Academy. From 5 December 1912 to 21 April 1913, she escorted the war prize, future Soya on a training cruise to Australia and Southeast Asia. Next she made one to North America and Hawaii with Asama fom 20 April to 11 August 1914. She was in reserve on 18 August, reassigned on 1 September 1915 for a training cruise between 20 April and 22 August 1916, to Australia and Southeast Asia. Next she became flagship of Destroyer Squadron 2, from 1 December 1916 to 28 March 1917 and 4 August to 24 January 1918. This was interrupted in 1917 by a diplomatic mission, returning the body of ambassador George W. Guthrie to the US. She was back with the Training Squadron on 10 August 1918 with Tokiwa, making two training cruises over the next two years (March-July 1919 to Australia-Southeast Asia) and Mediterranean 24 November-20 May 1920.
On 1 September 1921, she became a 1st-class coast-defence ship given her engines in bad shape, as well as TS for the Maizuru Naval Corps. In 1924 she had armaments changes, and on 1 October 1927, became a stationary training ship at Maizuru, for the engineering school. She was refitted in 1930 and remained active into WW2. She was at last stricken from the navy list, hulked, and disarmed in 1941, so before Pearl Harbour and still present in Yokosuka during the air raid on 18 July 1945, badly damaged. Likewise, she was scrapped in 1946.