YUSOSEN!

Stories and Battle Histories of the IJN's Fleet Oilers

10 May 2008

By Bob Hackett and Peter Cundall

Discussion & Questions



(Oiler by Takeshi Yuki scanned from "Color Paintings of Japanese Warships")

Oil was a key factor in the Empire of Japan's decision to go to war with America. After Japan occupied southern French Indochina in the summer of 1941, the United States, Great Britain and the Netherlands East Indies placed an embargo on all petroleum products into Japan.

Just before their attack on Pearl Harbor, the Japanese nation had only 49 merchant tankers of 587,000 tons and the IJN had but nine fleet oilers. Despite its prewar stockpiling of two years of petroleum products, Japan had to rely on imports from its conquered South Asia territories for survival.

Like all navies, oil was the lifeblood of the Imperial Japanese Navy. As a result, during the Pacific War, the IJN requisitioned 77 merchant ships from their owners for conversion to auxiliary oilers.

This page covers the activities of 30 fleet oilers - 18 merchant auxiliaries and 12 Navy oilers. Two of the Navy oilers also served in the seaplane tender role; another two were designed as aviation gasoline tankers to resupply carriers at sea. The latter Yusosen were officially termed Kihatsuyu Umpankan.

Tabular Records of Movement (TROMs):

Auxiliary Fleet Oilers

(Classes link to specifications summaries)

>
GENYO MARU Class

Genyo Maru (posted 11/3/2005)

Itsukushima Maru (posted 2/14/2005)
Kenyo Maru (posted 8/28/2006)
Kokuyo Maru (posted 11/3/2006)
Nichiei Maru (posted 2/6/2007)
Toei Maru (posted 3/29/2007)

KYOKUTO MARU Class

Kyokuto Maru (posted 7/27/2007)

Toa Maru (posted 7/27/2007)
Toho Maru (posted 7/27/2007)

FUJISAN MARU Class

Fujisan Maru(posted 9/14/2007)
NIPPON MARU Class

Nippon Maru (posted 11/9/2007)

Tatekawa Maru(posted 3/28/2008)

SHINKOKU MARU Class

Shinkoku Maru (posted 12/14/2007)
GOYO MARU Class

Goyo Maru (posted 3/28/2008)
HOYO MARU Class

Hoyo Maru (posted 5/10/2008)

AKEBONO Maru Class

Akebono Maru

STANDARD TANKER 1TL Class

Azusa Maru

Seiyo Maru


Naval Fleet Oilers

(Classes link to specifications summaries)

SHIRETOKO Class

Shiretoko (posted 9/14/2007)

Notoro (revised 5/29/2007)
Iro (posted 11/9/2007)
Erimo(posted 12/14/2007)
Tsurumi
Shiriya
Sata

KAMOI Class

Kamoi (posted 4/18/2006)
HAYASUI Class

Hayasui

KAZAHAYA Class

Kazahaya

SUNOSAKI Class

Sunosaki

ASHIZURI Class

Shioya

OSE Class

Ose

Bibliography of Sources

About the Authors

Mr. Robert Hackett is a military historian and researcher. Retired from the United States Air Force and later from the aerospace industry, he resides in the United States.

Mr. Peter Cundall is a maritime historian and researcher who specializes in merchant ships. He resides in Australia.

Questions to the authors concerning these TROMs should be posted on the Discussion and Questions board.