The was a class of seven oilers of 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...

 (IJN), serving during the 1920s and the World War II

World War II

World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...

. They were also called the , after the Notoro and the Shiretoko were converted to other ship types.

Construction

They were built under pre-Eight-eight fleet

Eight-eight fleet

The was a Japanese naval strategy formulated for the development of the Imperial Japanese Navy in the first quarter of the 20th century, which laid down that the Japanese navy should include eight first-class battleships and eight armoured cruisers or battlecruisers.-History and development:The...

 plans, the Eight-four fleet plan and the Eight-six fleet plan.

Pre-war service

The class devoted themselves to importing crude oil from North America and Southeast Asia. The Notoro and the Ondo class

Ondo class oiler

The was a class of three oilers of the Imperial Japanese Navy , serving during the 1920s and the World War II.-Construction:The Ondo class were initially planned in 1920 as the six of the Kamoi class oilers under the Eight-eight fleet final plan. However, the Kamoi class oilers were built only the...

 made 388 voyages carrying a total of 3,000,000 tons of oil up to 1941.

Service in the Pacific War

They were not able to accompany the fleet, because of their low speed. Instead they were engaged in a supply duties at naval bases.

Ships in class

Ship	Builder	Laid down	Launched	Completed	Fate
	Kawasaki-Kōbe Shipyard	24 November 1919	17 July 1920	20 September 1920	Converted to seaplane tender, 1 June 1934. Scuttled off Singapore Singapore Singapore , officially the Republic of Singapore, is a Southeast Asian city-state off the southern tip of the Malay Peninsula, north of the equator. An island country made up of 63 islands, it is separated from Malaysia by the Straits of Johor to its north and from Indonesia's Riau Islands by the... , 12 January 1947.
	Kawasaki-Kōbe Shipyard	24 November 1919	3 May 1920	10 August 1920	Converted to collier, 1928. Later re-converted to munition ship. Sunk by air raid at Singapore, 1 February 1945.
	Kawasaki-Kōbe Shipyard	3 May 1920	28 October 1920	16 December 1920	Heavily damaged by Dutch submarine O 15, 4 March 1942 and grounded at Belitung Belitung Belitung, , is an island on the east coast of Sumatra, Indonesia in the Java Sea. The island is known for its pepper and for its tin. It was in the possession of the British from 1812 until the British ceded control of the island to the Dutch in the Anglo-Dutch Treaty of 1824... .
	Yokohama Dock Company	6 March 1920	28 October 1920	24 February 1921	Converted to submarine rescue ship Submarine rescue ship A Submarine rescue ship serves as a surface support ship for submarine rescue and deep-sea salvage operations. Methods employed are the McCann Rescue Chamber, Deep Submergence Rescue Vehicles and deep sea diving operations....  in 1938. Sunk by air raid at Palau Palau Palau , officially the Republic of Palau , is an island nation in the Pacific Ocean, east of the Philippines and south of Tokyo. In 1978, after three decades as being part of the United Nations trusteeship, Palau chose independence instead of becoming part of the Federated States of Micronesia, a... , 31 March 1944.
	Ōsaka Iron Works, Sakurajima Factory	10 March 1921	29 September 1921	14 March 1922	Sunk by south of Davao Davao Davao refers to several closely related places in Mindanao in the Philippines. The term is used most often to refer to the city.*Davao Region, an administrative region*Davao del Norte province*Davao del Sur province*Davao Oriental province...  05°53′N 125°41′E, 5 August 1944.
	Yokohama Dock Company	7 April 1921	29 September 1921	8 February 1922	Sunk by northeast of Keelung Keelung Keelung City is a major port city situated in the northeastern part of Taiwan. It borders New Taipei and forms the Taipei–Keelung metropolitan area, along with the Taipei and New Taipei. Nicknamed the Rainy Port for its frequent rain and maritime role, the city is Taiwan's second largest seaport...  26°23′N 122°40′E, 22 September 1943.
	Ōsaka Iron Works, Sakurajima Factory	2 September 1921	5 August 1922	30 October 1922	Heavily damaged by air raid at Palau, 31 March 1944. Sank, 17 April 1944.