Japanese battleship Aki

The Japanese battleship Aki
Career (Japan)
Name:	Aki
Ordered:	1904
Builder:	Kure Naval Arsenal, Japan
Laid down:	15 March 1906
Launched:	14 April 1907
Commissioned:	11 March 1911
Struck:	7 September 1923
Fate:	Sunk as Target 7 September 1924
General characteristics
Class and type:	Satsuma class battleship
Displacement:	20,100 tons (normal); 21,800 tons (max)
Length:	140.21 m (460.0 ft) @ waterline; 150 m (492.1 ft) overall
Beam:	25.48 m (83.6 ft)
Draught:	8.38 m (27.5 ft)
Propulsion:	2-shaft Curtis Steam Turbine, 15 Miyabara boilers; 24,000 shp (17,900 kW)
Speed:	20 knots (37 km/h)
Range:	172 tons oil; 3000 tons coal
Complement:	931
Armament:	4 x 12-inch (305 mm)/45 caliber guns (2 x 2) 12 x 10-inch (254 mm)/45 caliber guns (6 x 2) 8 x 4.7-inch (119 mm)/40 caliber guns 3 x 3-inch (76 mm)/40 caliber guns 4 x 3-inch (76 mm)/28 caliber guns 5 x 18-inch (457 mm) torpedo tubes
Armour:	belt: 100-230 mm barbette:180-240 mm turret: 180- 200 mm conning tower: 150 mm deck: 50 mm

The Aki (安芸 (戦艦), Aki (senkan) was a semi-dreadnought type battleship of the Imperial Japanese Navy, designed and built in Japan by the Kure Naval Arsenal. The name Aki comes from Aki Province, now a part of Hiroshima prefecture.

Background

Funding for Aki was approved as part of the 1904 Emergency Budget for the Russo-Japanese War, and was the second battleship (after Satsuma) to be designed and built domestically in Japan. Due to priority given to the completion of the cruiser Tsukuba, construction of Aki took ten months longer than planned, but this allowed for various design defects discovered in the construction of Satsuma to be rectified in Aki.

Design

Right elevation and deck plan as depicted in Brassey's Naval Annual 1923

Aki was the first Japanese battleship with turbine engine propulsion, which allowed her to reach a speed of 20.7 knots (38 km/h) during trials in December 1910. The incorporation of the turbine engines necessitated a third funnel on what was originally the same hull design as Satsuma, increased the displacement by 450 tons, and the length of the hull by three meters. The turbine engines were imported from John Brown in Scotland.

Aki was initially designed as an all-big gun battleship (i.e. as a Dreadnought), but shortages of 12-inch (305 mm) guns only allowed her to have a combination armament.

Operational history

Aki was commissioned on 1911-03-11. During World War I, from August 1914, Aki was assigned to patrol the sea lanes south of Japan in the South China Sea and the Yellow Sea, but without a notable battle record. Indeed the only notable event in her wartime career was running aground on 1914-11-16 on a sandbank in Tokyo Bay.

As a result of the Washington Naval Agreement, Aki was decommissioned on 1923-09-20. It was expended as a naval artillery target, and sunk by Nagato and Mutsu off of Nojimasaki, southern Bōsō Peninsula, Chiba on 1924-09-27, in a ceremony witnessed by Crown Prince Hirohito and the heads of all the departments in the Japanese military. However, some of its larger guns were salvaged, and re-used in coastal artillery batteries around Tokyo Bay, including those at Misaki, Kanagawa, Miura Peninsula, and at Jogashima.

References

• Brown, D. K. (1999). Warrior to Dreadnought, Warship Development 1860-1906. Naval Institute Press. ISBN 1-84067-529-2. 
• Evans, David (1979). Kaigun: Strategy, Tactics, and Technology in the Imperial Japanese Navy, 1887-1941. US Naval Institute Press. ISBN 0870211927. 
• Howarth, Stephen (1983). The Fighting Ships of the Rising Sun: The Drama of the Imperial Japanese Navy, 1895-1945. Atheneum. ISBN 0689114028. 
• Jentsura, Hansgeorg (1976). Warships of the Imperial Japanese Navy, 1869-1945. Naval Institute Press. ISBN 087021893X. 
• Schencking, J. Charles (2005). Making Waves: Politics, Propaganda, And The Emergence Of The Imperial Japanese Navy, 1868-1922. Stanford University Press. ISBN 0804749779. 

External links

• Materials of the Imperial Japanese Navy