YUSOSEN!

Stories and Battle Histories of the IJN's Fleet Oilers

14 November 2009

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 about 587,000 tons and the IJN had but nine slow 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 85 fleet tankers - 55 merchant tanker auxiliaries, 19 Navy fleet oilers and 11 civilian merchant tankers in Japanese national service. Two of the Navy fleet oilers also served in the seaplane tender role and four were designed as aviation gasoline tankers to resupply carriers underway 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 (revised 10/3/09))
Kenyo Maru (revised 5/23/2009)
Kokuyo Maru (revised 5/23/2009)
Nichiei Maru (revised 5/23/2009)BR>
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)

Kaijo Maru No. 2 Go (posted 3/7/2009)

AKEBONO MARU Class

Akebono Maru (revised 5/23/2009)
TEIYO MARU Class

Teiyo Maru (posted 8/9/2008)

SAN RAMON MARU Class

San Ramon Maru (posted 11/8/2008)

San Clemente Maru (posted 8/23/2008)

SAN PEDRO MARU Class

San Pedro Maru (posted 12/27/2008)

San Luis Maru (revised 5/23/2009)
San Diego Maru (posted 11/15/2008)

OTOWASAN MARU Class

Omurosan Maru (posted 1/10/2009)
OGURA MARU No. 2 Class

Ogura Maru No. 2 (revised 5/23/2009)
OGURA MARU No. 3 Class

Ogura Maru No. 3 (posted 1/17/2009)
KIRISHIMA MARU Class

Kirishima Maru (revised 5/23/2009)

NISSHO MARU Class

Nissho Maru (posted 2/28/2009)
KYOKUYO MARU Class

Kyokuyo Maru (posted 5/9/2009)

TOEN MARU Class

Toen Maru (posted 5/16/2009)

TONAN MARU No. 2 Class

Tonan Maru No. 2 (posted 5/30/2009)

Tonan Maru No. 3 (posted 6/6/2009)
HISHI MARU No. 2 Class

Hishi Maru No. 2 (posted 7/18/2009)
MOJI MARU Class

Moji Maru (posted 7/5/2009)
KYOEI MARU No. 3 Class

Kyoei Maru No. 3 (posted 8/22/2009)
ARIMA MARU Class

Arima Maru

Azuma Maru
STANDARD TANKER 1TL Class

Azusa Maru (posted 6/28/08)

Seiyo Maru (posted 8/1/09)
Miri Maru (posted 8/8/09)
Kyuei Maru (posted 10/10/09)
Ryoei Maru (posted 10/17/09)
Nampo Maru (posted 10/31/09)
Nippo Maru
Ominesan Maru
Okikawa Maru
Amatsu Maru

STANDARD TANKER 1TM Class

Yuho Maru (posted 8/15/09)

Tarakan Maru(posted 8/29/09)
Manei Maru (posted 10/24/09)
Ryuei Maru (posted 11/7/09)
Shimpo Maru (posted 11/14/09)
Asanagi Maru
Asashio Maru

STANDARD TANKER 2TE Class

Murotsu Maru (posted 9/5/09)

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 (revised 5/23/2009)
Shiriya (revised 5/23/2009)
Sata (revised 5/23/2009)
Ondo (revised 5/23/2009)
Hayatomo (posted 1/31/2009)
Naruto (posted 4/6/2009)

KAMOI Class

Kamoi (posted 4/18/2006)
HAYASUI Class

Hayasui

KAZAHAYA Class

Kazahaya

SUNOSAKI Class

Sunosaki

Takasaki

ASHIZURI Class

Ashizuri (posted 6/20/2009)

Shioya (posted 7/25/09)


HARIO Class

Hario (posted 10/3/09)
OSE Class

Ose

Civilian Merchant Tankers in Japanese National Service

(Classes link to specifications summaries)


OTOWASAN MARU Class

Otowasan Maru(posted 9/12/2009)


EIYO MARU Class

Eiyo Maru


CHIYODA MARU Class

Chiyoda Maru

Chihaya Maru

TONAN MARU Class

Tonan Maru

STANDARD TANKER 1TL Class

Hakko Maru

Hakko Maru No. 2
Hashidate Maru


STANDARD TANKER 1TM Class

Jambi Maru

Sarawak Maru

STANDARD TANKER 2TL Class

Jinei Maru


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.