TETSUSEI DAI HATSUDOTEI

© 2010-2011 Bob Hackett and Peter Cundall

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4 November 1942:
Tamano. Laid down at Mitsui Shipbuilding as an M class transport.

1943:
Requisitioned by the IJA while under construction. Converted to a 9,589-ton landing craft depot ship.

18 August 1943:
Launched and named TAMATSU MARU.

20 January 1944:
Completed.

13 February 1944:
Departs Ujina.

16 February 1944:
TAMATSU MARU departs Moji in convoy HI-45 also consisting of transports ARIMASAN MARUs and tankers OMUROSAN, ITSUKUSHIMA, KUROSHIO and TATEKAWA MARUs, and very likely SEIYO MARU, escorted by destroyer SHIOKAZE.

20 February 1944:
SHIOKAZE detaches from the convoy.

21 February 1944:
KUROSHIO MARU develops engine trouble and is detached for Takao.

22 February 1944:
Kaibokan MIYAKE joins the convoy.

23 February 1944:
TAMATSU MARU is detached for Manila.

15 March 1944:
Departs Manila.

29 March 1944:
Arrives at Kobe.

13 May 1944:
At 0400, TAMATSU MARU and IJA landing craft depot ship KIBITSU MARU depart Moji for Singapore in convoy HI-63 also consisting of cargo liners/transports SANUKI, SANYO, AWA, TEIA (ex-French liner ARAMIS), USSURI and NISSHO MARUs, tankers KYOKUHO, RYOEI and OTOWASAN MARUs escorted by kaibokan IKI, MATSUWA, CD-9 and CD-15.

Four of the transports carry troops bound for Burma. NISSHO MARU and IJA landing craft depot ships TAMATSU and KIBITSU MARUs are bound for the Philippines and carry the bulk of the IJA 30th Division (less its transportation and reconnaissance regiments) that they moved from Pusan, Korea.

18 May 1944:
At 1800, arrives at Manila. TAMATSU, KIBITSU and NISSHO MARUs are detached for Cagayan, Philippines.

21 May 1944:
Departs Manila.

23 May 1944:
Arrives at Cagayan, PI. Meanwhile at 0700, Convoy HI-62 departs Singapore for Moji consisting of transports KINUGASA, NOSHIRO, NISSHO and TEIRITSU (ex-French LECONTE de LISLE) MARUs and tankers OTORISAN, SARAWAK and NICHINAN MARUs escorted by escort carrier TAIYO and kaibokan KURAHASHI, SADO, CD-5, CD-7 and CD-13.

24 May 1944:
Departs Cagayan and later that day arrives at Cebu.

27 May 1944:
Departs Cebu.

29 May 1944:
HI-62 arrives at Manila. TAMATSU MARU also arrives at Manila that day from Cebu and joins the convoy.

1 June 1944:
At 0400, HI-62 departs Manila.

8 June 1944:
Arrives at Mutsure anchorage, later proceeds to Moji arriving at 0230.

3 July 1944:
TAMATSU MARU departs Moji for Manila in convoy MOMA-01 also consisting of KASHII, TOZAN, NISSHO, MAYASAN, MIZUHO and NICHIRAN MARUs escorted by destroyer HARUKAZE and kaibokan CD-11, CD-20, CD-26 and CD-28 and subchaser CH-28. The convoy is transporting the IJA's 5th Field Heavy Artillery and 58th Independent Mixed Brigade.

7 July 1944:
Formosa Straits. Convoy MOMA-01 is ordered to turn back to Kirun (Keelung), Formosa (Taiwan).

9 July 1944:
Departs Keelung escorting MOMA-01. ARABIA MARU may have joined the convoy at this point.

12 July 1944:
Bashi Strait. At 0330, LtCdr Walter P. Schoeni's APOGON (SS-308) fires a full bow spread of torpedoes MAYASAN MARU. Schoeni fails to damage her, but APOGON is rammed during the attack. At 0720, LtCdr Harold E. Rubles' USS PIRANHA (SS- 389) torpedoes and sinks NICHIRAN MARU at 18-50N, 122-40E. KASHII MARU rescues survivors, but 1262 troops are KIA. The convoy seeks shelter in Aparri Harbor, Philippines.

13 July 1944:
At 0800, departs Aparri.

15 July 1944:
Arrives at Manila.

24 July 1944:
At 0600, convoy HI-68, that left Singapore on 14 July, departs Manila for Moji. The convoy includes some ships from the Manila leg of HI-69 and MOMA-01. Convoy HI-68 sails in three columns: column no. 1 consists of landing ship MAYASAN MARU, tankers OTORISAN MARU and NICHINAN MARU No. 2 and escort carrier TAIYO; column no. 2 consists of TAMATSU MARU and transports TOSAN, KASHII, NISSHO and AKI MARUs; column no. 3 consists of transport KIYOKAWA MARU and tankers TOA, TOHO, SHIMPO and ITSUKUSHIMA MARU.

Convoy HI-68’s escorts include escort carrier KAIYO, kaibokan HIRADO (F), KURAHASHI, ISHIGAKI, KUSAGAKI, MIKURA, CD-11 and CD-20 and torpedo boat HIYODORI. The ships sail at 11.5 knots, the average speed for HI series convoys.

A three-submarine wolf pack of Cdr (later Rear Admiral) Rueben T. Whitaker’s USS FLASHER (SS-249), LtCdr Franklin Hess’s ANGLER (SS-240) and LtCdr Francis D. Walker’s CREVALLE (SS-291) attacks the convoy.

25 July 1944:
Off NW Luzon. At 1540, transports AKI and TOSAN MARUs succesfully evade an attack by CREVALLE.

26 July 1944:
Off Luzon. At 0211, in a night surface radar attack, Whitaker’s FLASHER torpedoes and damages TOSAN MARU and sinks AKI and OTORISAN MARUs. Hess’s ANGLER torpedoes and blows the bow off KIYOKAWA MARU. At 0655, the ship leaves the convoy and heads for Takao, Formosa.

At 1137, Walker’s CREVALLE torpedoes and further damages TOSAN MARU. Later, she catches fire.

27 July 1944:
At 0430, the fires ignite 1,000 stored shells and by 1045, TOSAN MARU sinks. Nine crewmen, 8 gunners and 18 passengers are KIA. The remainder of the convoy arrives at Takao. SHIMPO MARU is detached.

28 July 1944:
Departs Takao escorted by kaibokan MIKURA, KURAHASHI, HIRADO, CD-1 andCD-11.

E 29 July 1944:
CD 1 is detached for Kirun (Keelung).

3 August 1944:
At 1600, arrives at Moji.

6 August 1944:
Departs Moji for Fusan (Pusan), Chosen (Korea).

8 August 1944:
TAMATSU MARU departs Fusan and arrives at Imari Bay later that day.

10 August 1944:
At 0500, TAMATSU MARU departs Imari Bay for Singapore with convoy HI-71 also comprised of fleet oiler HAYASUI, oilers AZUSA, TEIYO, EIYO, ZUIHO, KYOKUTO and NIYO MARUs and HAKKO MARU No. 2, armed merchant cruiser NOSHIRO MARU, landing ship carriers KIBITSU and MAYASAN MARUs, transports TEIA (ex-French liner ARAMIS), AWA, ORYOKU, NOTO and HOKKAI MARUs, food-supply ship IRAKO and cargo ships KASHII and NISSHO MARUs.

HI-71’s screen is provided by Rear Admiral (Vice Admiral, posthumously) Kajioka Sadamichi's (former CO of KISO) 6th Escort Convoy Command's destroyers FUJINAMI and YUNAGI, kaibokan HIRATO, KURAHASHI, MIKURA, SHONAN, CD-11 and escort carrier TAIYO. Her 631st Naval Air Group provides air cover with 12 Nakajima B5N “Kate” torpedo-bombers.

15 August 1944:
HI-71 arrives at Mako, Pescadores. HAKKO MARU No. 2, NIYO and ORYOKU MARUs and IRAKO are detached.

17 August 1944:
HI-71 sorties from Mako for Manila, part of the “Sho” Operation, transporting troops and supplies for the defense of the Philippines. Destroyer ASAKAZE and kaibokan SADO, ETOROFU, MATSUWA and HIBURI sent from Takao to augment the escort on the orders of 1st Surface Escort Division.

18 August 1944:
At 0524, LtCdr Louis D. McGregor's USS REDFISH (SS-395) torpedoes and damages 8,673-ton EIYO MARU. Destroyers ASAKAZE and sister YUNAGI are detached to escort EIYO MARU back to Takao.

At 2222, escort carrier TAIYO, bringing up the rear of the convoy, is hit in her starboard quarter by three of four torpedoes fired by RASHER in a surface radar attack. Set afire, she sinks quickly taking down most of her 850 man crew with her.

At 2310, RASHER, on the surface, hits transport TEIA MARU (ex-French liner ARAMIS) carrying 4,795 Army and 427 civilians. Hit by three of four torpedoes and set afire, she sinks. 2,316 troops, 275 passengers, 6 guards, 4 gunners, 10 special lookouts and 54 crewmen are KIA.

19 August 1944:
The convoy splits into two groups. Just past midnight, LtCdr Munson's RASHER, still running on the surface, closes on an eastbound group of three large ships with one escort. At 0033, Munson puts two radar directed torpedoes into the port sides of NOSHIRO and AWA MARUs. Both ships beach themselves near Port Curiman. AWA MARU is later taken under tow and arrives in Manila on 21 August after the main body of the convoy.

LtCdr Charles M. Henderson's USS BLUEFISH (SS-222) and LtCdr Gordon W. Underwood's SPADEFISH (SS-411), on her first patrol, join in the attack on HI-71. At 0320, BLUEFISH hits fleet oiler HAYASUI. She bursts into flames and drift for a while before finally sinking about 0600.

At 0510, BLUEFISH torpedoes oiler TEIYO MARU in a surface radar attack. Hit by three of six torpedoes, she is set afire and awash to amidships, bow and bridge high in air, she sinks by the stern 35 minutes later. 41 crewmen and 58 passengers are KIA.

At 0333 (H), LtCdr Underwood's SPADEFISH, comes in at radar depth and fires six bow Mark-23 steam torpedoes at TAMATSU MARU. The first two of the salvo hit the big landing craft depot ship. Her screws stop and she rolls over and sinks at 17-34N, 119-24E taking down 4,755 troops and 135 merchant seamen. [1]

That afternoon, one of the convoy's escorts discovers TAMATSU MARU's debris field littered with wreckage and about 2,000 bodies drifting in the water.

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Authors’ Notes:
[1] TAMATSU MARU was carrying the IJA’s 2nd Battalion and regimental headquarters of the 13th Independent Infantry Regiment (26th Division) and division and regiment communications troops. She also carried four of the twelve 100-mm guns of the 22nd Field Heavy Artillery Regiment and one of the four 300-mm howitzers of the 4th Independent Heavy Artillery Battalion. The 19th Independent Rapid Fire Artillery Battalion was aboard with about 480 men and twelve 47-mm antitank guns. Included were various headquarters and airfield units. One 179-man airfield management section was bound for the Philippines. The IJA’s 6th Aviation Signal Regiment was heading for Cebu.

The sinking of TAMATSU MARU was the worst merchant disaster of the Pacific War and the fourth worst loss of life on any Japanese vessel during the war.

Thanks go to John Whitman of the USA for data on the troops carried by TAMATSU MARU.

-Bob Hackett and Peter Cundall

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