IJA Supply Ship/IJN Transport/IJA Hospital Ship ARIMASAN MARU:
Tabular Record of Movement

©2012-2013 Bob Hackett

28 December 1936:
Laid down at Tama Shipyard Co., Ltd. as a 8,697-ton passenger cargo ship for Mitsui Bussan, K.K.

28 April 1937:
Launched and named ARIMASAN MARU.

3 July 1937:

30 July 1937:
Departs Yokohama.

10 August 1937:
Arrives at San Francisco, California.

Arrives at San Pedro, California.

May 1938:
Los Angeles, California. ARIMASAN MARU collides with S. S WALTER A. LUCKENBACH in the harbor area.

April 1940:
Isthmus of Panama. USS J. FRED TALBOTT (DD-247) departs the Canal Zone to rendezvous at sea with ARIMASAN MARU and provide medical assistance to a passenger on board the steamship.

April 1941:
Massachusetts. Runs aground on a bank of Cape Cod's south canal.

Enters dock in an unknown New Jersey shipyard and undergoes inspection and repair for one week.

September 1942:
Requisitioned as an Army supply ship. Departs Osaka for Rangoon, Burma (now Yangon, Myanmar) and return.

30 October 1942:
Departs Kobe for Singapore in IJA service.

May 1943:
Requisitioned by the Imperial Navy (IJN).

1 July 1943:
Departs Palau. At about 0900, LtCdr Charles H. Andrews USS GURNARD (SS-254) attacks convoy FU-105 also consisting of SHINYUBARI and HIGASHI MARUs and an unidentified ship escorted by torpedo boat HATO at 07-37N, 134-26 E. In several attacks, Andrews fires 11 torpedoes, but they all miss or premature.

1 July 1943:
ARIMASAN MARU departs Palau for Kobe via Saeki in convoy FU-105 also consisting of TAITO and SHINYUBARI MARUs escorted by torpedo boat HATO.

Shortly after departure LtCdr (later Rear Admiral) Charles H. Andrews’ (USNA ‘30) USS GURNARD (SS-254) intercepts the convoy. At 0900, Andrews launches several unsuccessful attacks against the convoy firing a total of 11 torpedoes that all miss.

Naval oiler TSURUMI and IJN hospital ship MURO MARU report seeing torpedo tracks. Later, Japan protests the attack on MURO MARU. [1]

11 July 1943:
Arrives at Kobe.

17 July 1943:
At 1800, ARIMASAN MARU departs Moji in a convoy consisting of oilers HOYO, TACHIBANA and TAKETSU MARUs and Navy transports DURBAN and HAKONE MARUs and three unidentified ships with subchaser CH-9 and an auxiliary gunboat as escorts.

22 July 1943:
At 1320, arrives at Takao, Formosa.

25 July 1943:
ARIMASAN MARU joins convoy HI-03 at Takao consisting of AWA, ASAMA and NANKAI MARUs and tanker OMUROSAN MARU escorted by kaibokan ETOROFU.

26 July 1943:
At 1600, convoy HI-03 departs Takao.

29 July 1943:
At 1650, surfaced German submarine U-511 inbound from France encounters convoy HI-03 bound for Singapore. The sight of the submarine causes confusion aboard OMUROSAN MARU. Her gunners fire three shells at U-511, before the mistake is cleared up. The skipper of ETOROFU (convoy commander) inspects U-511 and personally apologizes for the attack.

1 August 1943:
At 1400, convoy HI-03 arrives at Singapore.

7 December 1943:
ARIMASAN and TOZAN MARUs and tanker SHINSHU MARU (4,182-tons) depart Takao in an unidentified convoy probably consisting of several other ships and unknown escorts.

12 December 1943:
Arrives at Singapore. 26 December 1943:
At 1000 departs Singapore in HI-26 convoy believed to also consist of AMATSU, OTOWASAN MARUs, TAKASAKI and possibly up to three unidentified merchant ships escorted by kaibokan TSUSHIMA.

1 January 1944:
Arrives at Takao. TSUSHIMA is detached.

3 January 1944:
Departs Takao in convoy HI-26 is now increased by IJA landing craft depot ship SHINSHU MARU and TOZAN, NOTO, MIIKE and MAYASAN MARUs escorted by light cruiser KASHII and probably other unknown escorts.

7 January 1944:
At 1830, arrives at Moji.

16 February 1944:
At 0600, convoy HI-45 departs Moji for Singapore consisting of ARIMASAN MARU, IJA landing craft depot ship TAMATSU MARU, tankers ITSUKUSHIMA, KUROSHIO, OMUROSAN and TATEKAWA MARUs and an unidentified ship escorted by destroyer SHIOKAZE.

20 February 1944:
Destroyer SHIOKAZE is detached.

21 February 1944:
KUROSHIO MARU suffers engine trouble and is detached for Takao, Formosa.

22 February 1944:
Kaibokan MIYAKE joins the escort.

23 February 1944:
TAMATSU MARU and is detached for Manila. Destroyer SHIOKAZE rejoins the escort.

27 February 1944:
At 1700, arrives at Singapore.

29 March 1944:
At 0950, convoy HI-54 departs Singapore consisting of ARIMASAN, NANKAI. MIRI and KYOKUHO MARUs escorted by kaibokan AWAJI.

31 March 1944:
Arrives and anchors at Cap St. Jacques, Indochina (Vung Tau, Vietnam).

11 April 1944:
Cap St. Jacques. Convoy HI-54 is joined by convoy HI-56 consisting of tanker ASANAGI MARU and five unidentified ships and an unidentified escort vessel.

14 April 1944:
At 0800, reconstituted convoy HI-56 departs Cap St. Jacques for Takao, Formosa.

4 April 1944:
The combined convoy departs Cap St. Jacques.

19 April 1944:
The convoy arrives at Takao.

24 April 1944:
Arrives at Moji.

25 May 1944:
ARIMASAN MARU departs Pusan in an unidentified convoy with transports SHINSHU and KASHI MARUs. The convoy carries the 30th Division’s Reconnaissance Regiment (minus 3rd Company), 1st Company, part of the division's Signal Unit, Medical Unit, 1st Field Hospital, Ordnance Duty Unit main force, Transport Regiment and Veterinary Hospital. Later that day, the convoy arrives at Moji.

29 May 1944:
At 0600, ARIMASAN MARU departs Moji escorting convoy HI-65 also consisting of cargo ships/transports MANILA, KASHII and TATSUWA MARUs and IJA landing craft depot ship SHINSHU MARU and tankers SHIRETOKO, ITSUKUSHIMA, OMUROSAN, ZUIHO and TOHO MARUs escorted by escort carrier SHINYO, light cruiser KASHII, kaibokan AWAJI, CHIBURI and CD-11 and subchasers CH-19 and CH-60.

ARIMASAN MARU carries replacements for the 18th Division and other Burma units. Weaponless soldiers out of Japan of the 1st through 6th Specially Established Machine Cannon Units are en route to Halmahera and the Celebes where they are to be equipped with Navy single-barrel 25mm machine cannons that were already on site. Ten more fully-equipped specially established machine cannon units (11, 13, 15, 17-19, 22-25) are headed for the Philippines.

E 30 May 1944:
Light minelayer TSUBAME joins the convoy's escort from Kagoshima.

2 June 1944:
Bashi Strait near Yasho Island, E of Formosa. About 2300, AWAJI is torpedoed by LtCdr (later Captain) Enrique D. Haskins' (USNA ’33) new USS GUITARRO (SS-363) and sinks near Yasho Island at 22-34N, 121-15E. CHIBURI and CD-19 rescue survivors, but several die of wounds.

LtCdr (later Captain) Albert L. Raborn's (USNA ’34) USS PICUDA (SS-382) fires two torpedoes that exlode prematurely near ARIMASAN MARU and clause slight damage, but in the confusion, while trying to avoid oiler SHIRETOKO, ARIMASAN MARU collides with SHINSHU MARU's stern. The collision and the explosion of twelve ready depth charges on the stern of SHINSHU MARU kills 25 men on ARIMASAN MARU and 255 soldiers on SHINSHU MARU. The explosion “cracks” the aft portion of SHINSHU MARU. Light cruiser KASHII takes SHINSHU MARU in tow. ARIMASAN MARU is lightly damaged in the attack and heads for Kirun (Keelung) with KASHII and SHINSHU MARU.

3 June 1944:
Arrives at Kirun.

4 June 1944:
ARIMASAN, MANILA, KASHII and TATSUWA MARUs depart Kirun for Manila.

11 June 1944:
Manila. Convoy MI-05 en route since 3 June from Imari Bay to Miri, Borneo is joined by cargo ships/transports ARIMASAN, MANILA, MIIKESAN and USSURI MARUs and tankers SAN DIEGO MARU and KYOEI No. 8 and JINEI MARU from Takao. Minelayer MAESHIMA and auxiliary subchaser CHa-95 join the escort.

The convoy now consists of cargo/transports KENEI, HINAGA, NIPPO (ex-Chinese NINGPO), FUYUKAWA, SURAKARUTA and TATSUJU MARUs, fleet oiler NOTORO and tankers AYANAMI, AYAGIRI, BAIEI, CERAM, TACHIBANA, SAN DIEGO, NITTETSU, YAMASACHI, KENZUI, OEI, TOKUWA and MARIFU MARUs, YAMAMIZU MARU No. 2 and 13 unidentified merchant ships escorted by kaibokan CD-14, CD-18, torpedo boat SAGI, patrol boat PB-38, minesweeper W-17, auxiliary subchaser CHa-22 and two unidentified warships.

13 June 1944:
LtCdr John D. Crowley's USS FLIER (SS-250) torpedoes and damages MARIFU MARU at 15-57N, 119-42E. She is taken in tow by MIIKESAN MARU.

15 June 1944:
The convoy arrives Manila. Damaged MARIFU MARU arrives later and is detached.

18 June 1944:
Convoy MI-05 departs Manila. It now consists of cargo/transports ARIMASAN, HINAGA, NIPPO, TATSUJU, SURAKARUTA, TEIFU, ROKKO, DAIZEN, MIIKESAN , NICHIYO, HIDA and SEIWA MARUs and tankers TACHIBANA, JINEI, SAN DIEGO, BAIEI, KENZUI, ATAGO, AYANAMI, CERAM, OEI and TOKUWA MARUs, YAMAMIZU MARU No. 2, KYOEI MARU No. 8, fleet oiler NOTORO with the same escorts.

23 June 1944:
At 1257, arrives at Miri.

25 June 1944:
At 1915, ARIMASAN MARU departs Miri for Singapore in convoy MISHI-03 consisting of cargo/transports TEIFU (ex-Vichy French BOUGAINVILLE), SEIWA, NIPPO, DAIZEN, SURAKARTA, HIDA, HINAGA MANILA, ROKKO, TATSUTAMA (ex-American SS Admiral Y. S. WILLIAMS), TOA and KENZUI MARUs, fleet oiler NOTORO and tankers SAN DIEGO, NICHIYO, JINEI, BAIEI, FUYUKAWA and AYANAMI MARUs and KYOEI No. 8 escorted by kaibokan CD-18, torpedo boat SAGI, minesweeper W-17, subchaser CH-21 and auxiliary minesweepers CHOUN MARU No. 6 and TOSHI MARU No. 2.

28 June 1944:
South China Sea, off Singapore. At 2100, Cdr (later Rear Admiral) Rueben T. Whitaker’s (USNA '34) USS FLASHER’s (SS-249) radar picks up the convoy. Whitaker, operating in relatively shallow water (150 feet), decides to wait until after the moon sets to make a surface attack on the convoy’s two largest ships.

29 June 1944:
At 0111, Whitaker torpedoes freighter NIPPO MARU and oiler NOTORO. At 0117, two or three torpedoes hit NIPPO MARU and two or three torpedoes hit NOTORO. NIPPO MARU breaks in two and sinks by the bow. NOTORO remains afloat, but goes dead in the water. The escorts begin blindly dropping depth charges. Whitaker, still on the surface, leaves the area on four engines.

30 June 1944:
Arrives at Singapore.

4 August 1944:
At 2100, ARIMASAN MARU departs Singapore for Moji in convoy HI-70 also consisting of MANJU and KINUGASA MARUs and oilers SERIA, KUROSHIO, HAKKO, OMUROSAN and OTOWASAN MARUs escorted by escort carrier SHINYO, light cruiser KASHII, destroyer SHIMOTSUKI and kaibokan CHIBURI, SADO, CD-13 and CD-19.

12 August 1944:
SADO is detached to hunt an enemy submarine. Later, she separately proceeds to Keelung (Kirun).

15 August 1944:
At 1430, convoy HI-70 arrives at Moji.

26 October 1944:
At 1730, ARIMASAN MARU departs Mutsure in convoy HI-79 also consisting of transports KAGU and MELBOURNE MARUs, fleet supply ship MAMIYA and oilers TENEI and MATSUSHIMA MARUs. Initially, the escorts are light cruiser KASHI, with Rear Admiral Yoshitomi Setsuzo, CINC, 5th Escort Group embarked, kaibokan NOMI and UKURU and minelayer NIIZAKI.

27 October 1944:
Kaibokan CD-17 joins the escort.

28 October 1944:
Minesweeper W-21 joins the escort.

29 October 1944:
MELBOURNE MARU escorted by UKURU and CD-17 are detached and head for Kirun.

30 October 1944:
HI-79 arrives at Takao. KAGU MARU, MAMIYA and minesweeper W-21 are detached from the convoy. RYOEI MARU joins the convoy bound for Singapore.

9 November 1944:
HI-79 arrives at Singapore.

17 November 1944:
ARIMASAN MARU departs Singapore in convoy HI-80 also consisting of tankers TENEI, MATSUSHIMA, RYOEI, MUNEKATA, KUROSHIO, NICHINAN and KAIHO MARUs and transport ARIMASAN MARU escorted by light cruiser KASHII (F) with Rear Admiral Yoshitomi Setsuzo, CINC, 5th Escort Group embarked, kaibokan MANJU, NOMI, KASADO, MIYAKE, UKURU, CD-17, CD-23 and CD-51 and minelayer NIIZAKI.

20 November 1944:
At 1240, CD-17 is detached for Saigon.

27 November 1944:
At 0930, ARIMASAN and RYOEI MARUs escorted by NIIZAKI are detached for Takao.

5 December 1944:
At 1157, ARIMASAN MARU departs Takao in convoy TAMA-35 also consisting of NISSHO, ORYOKU and KAZUURA MARUs escorted by kaibokan DAITO, CD-1 CD-34 and CD-134. The ships carry the 13th Independent Field Artillery Battalion, Navy personnel, men from the 10th and 23rd Divisions and the 5th and 6th Medium Mortar Battalions. The ships also carry smooth bore 203mm Type 4 rocket launchers of the 845-man 3rd Rocket Launcher Battalion, 60 horses with 60 towed carts. A a ten-truck ammunition train carries the weapons and their fin-stabilized ammunition.

ARIMASAN MARU carries 10th Division headquarters, 39th Infantry, 2nd Battalion, 10th Artillery, reconnaissance engineer battalions, communications company and medical and transportation elements.

ORYOKU MARU carries 2,054 soldiers including the 558-man 4th Medium Mortar Battalion with twelve 150mm tubes and the unit’s ammunition, baggage and four trucks, a company of 23rd Division engineers and that regiment’s material platoon, Replacements for Luzon-based units such as the Army’s 10th Air Intelligence Regiment (observation and radar).

6,526 ton NISSHO MARU carries the regimental headquarters and the 1st and 2nd Battalions, 71st Infantry of the 23rd Division and Headquarters and Supply Company and thr 136th Airfield Battalion.

TEIHOKU (ex-Vichy French) PIERRE L.D. MARU carries 1,216 Navy personnel and 4,700 tons of supplies and equipment. Some of that equipment belongs to the 328th Naval Construction Unit, a 450-man airfield unit with rollers, scrapers, and various trucks. CD-134 carries 100 soldiers.

Later that day, TAMA-35 anchors at Chechung.

6 December 1944:
At 0058 departs and at 1815 anchors at Port San Pio Quinto, Camiguin Island.

8 December 1944:
At 0502, departs Port San Pio Quinto. At 1411, anchors at Calayan Island.

9 December 1944:
At 0817, departs Calayan Island.

11 December 1944:
At 2000, arrives at Manila.

14 December 1944:
Departs Manila.

18 December 1944:
ARIMASAN MARU suffers a near-miss bomb dropped by a Consolidated B-24 “Liberator” heavy bomber near Penghu Island at 23-00 N, 119-20.

E 19 December 1944:
Arrives at Takao.

6 January 1945:
Departs Takao.

7 January 1945:
Arrives at Kirun.

12 January 1945:
ARIMASAN MARU departs Kirun in convoy TAMO-35 also consisting of one unidentified merchant ship escorted by kaibokan MIKURA, SHIMUSHU, CD-2, CD-66, CD-67 and one unidentified warship.

18 January 1945:
Arrives at Moji.

23 January 1945:
Departs Moji.

24 January 1945:
Arrives at Pusan.

27 January 1945:
Departs Pusan and arrives at Moji later that day.

29 January 1945:
Departs Moji

3 February 1945:
Arrives at Osaka.

4 February 1945:
Arrives at Tamano.

8 February 1945:
Tamano. Enters dock at Mitsui Engineering and Shipbuilding Co., Ltd. Undergoes a special inspection and repair work, then begins outfitting as a hospital ship. Large red crosses are placed on the deck and sides.

23 February 1945:
The Japanese Ministry of Foreign Affairs, as required by the Geneva Convention, notifies the warring countries that ARIMASAN MARU is a designated hospital ship.

1 March 1945:
Requisitioned by the Imperial Army (IJA) once again.

20 March 1945:
Departs Moji.

28 March 1945:
Arrives at Kirun.

29 January 1945:
Departs Kirun.

6 April 1945:
Arrives at Singapore.

7 April 1945:
Departs Singapore.

20 April 1945:
Arrives at Moji.

15 August 1945: Cessation of Hostilities:
The Potsdam Declaration is accepted by Japan.

Resumes service for the Mitsui Line. Transports rice from Thailand to Japan.

February 1951:
Placed on Mitsui's Japan ~ New York route.

Reengined with a turbo-charged engine.

Chartered to Mitsui-OSK Line affiliate Toyo Kaiun. Renamed KATSURAGA MARU.

Renamed CHOKYU MARU. Scrapped.

Authors’ Notes:
[1] It is unclear whether TSURUMI was the unidentified ship in convoy FU-105. Almost certainly MURO MARU was not in the convoy as hospital ships travelled alone and unescorted.

Thanks go to John Whitman of Virginia for info about TAMA-35 and other assistance.

Bob Hackett

Back to IJA Transports