KUSENTEI!

© 2005-2007 Bob Hackett, Sander Kingsepp and Peter Cundall

---

1941:
Tokyo. Laid down at the Ishikawajima shipyard.

7 March 1942:
Launched and numbered CH-31.

15 June 1942:
Completed and registered in the Yokosuka Naval District.

14 July 1942:
Assigned to the 8th Base Force at Rabaul in Vice Admiral Mikawa Gunichi's (38)(former CO of KIRISHIMA) newly formed 8th Fleet.

25–26 August 1942:
Participates in capture of Nauru, Gilbert (now Kiribati) Islands.

September 1942:
Arrives at Rabaul.

23 October 1942:
Rabaul. CH-31 and CH-32 are bombed and damaged by USAAF Boeing B-17 "Flying Fortresses".

November 1942:
Arrives at Yokosuka. Undergoes bomb-damage repairs.

December 1942:
Arrives at Rabaul. Escorts convoys.

1 March 1943:
Truk. Reassigned to the Fourth Fleet's 4th Base Force.

10 March 1943:
CH-31 departs Kavieng, New Ireland escorting NISSHUN MARU (unconfirmed) to the latitude of the Equator and returns to Kavieng.

Mid-March 1943:
CH-31 departs Kavieng for Rabaul escorting aircraft ferry MOGAMIGAWA MARU.

4 May 1943:
At 1500, CH-31 departs Ponape escorting KUMAGAWA MARU.

26 June 1943:
At 0800, CH-31 departs Saeki with patrol boat PB-31 escorting convoy O-503 consisting of NICHIZUI, TATSUMIYA and HAVRE MARUs.

2 July 1943: Arrives at Palau.

11 September 1943:
CH-31 departs Kwajalein with auxiliary subchaser CHa46 and possibly CH-16 escorting convoy No. 6113 consisting of fleet oiler SHIRETOKO, cargo ships CHIHAYA, KATORI and FUJIKAWA MARUs and possibly others .

12 September 1943:
Alerted by an Ultra signal, LtCdr Carter L. Bennett's USS PERMIT (SS-178) intercepts the convoy. Bennett sets up and fires six torpedoes at three ships in submerged night attacks. He hits and damages FUJIKAWA MARU at 08-33N, 165-12E. Later, she is towed back to Kwajalein by CHIHAYA MARU. Soon after, in a second attack, PERMIT gets two hits on SHIRETOKO. That same day, light cruiser NAKA departs Truk to assist the torpedoed ships.

13 September 1943:
In the morning, Bennett continues his attack on the convoy. He fires three torpedoes at SHIRETOKO and claims three hits. Bennett last sees her low in the water. Later, she is taken in tow by KATORI MARU.

16 September 1943:
CH-31 arrives at Roi with CHa-46 and cruiser NAKA escorting KATORI MARU towing SHIRETOKO.

18 September 1943:
CH-31 departs Kwajalein with CH-28, auxiliary subchasers KYO MARU No. 6 and TAKUNAN MARU No. 10 and torpedo boat HIYODORI escorting convoy 6188 consisting of KEMBU, CHIHAYA, MINATO, TSUNESHIMA, SHIGANOURA, MUKO and KENRYU MARUs.

25 September 1943:
Arrives at Truk.

30 September 1943:
At 1000, CH-31 departs Truk with auxiliary subchasers KYO MARU No. 6 and CHa-18 escorting a convoy consisting of MATSUTAN (SHOTAN) and SEIKAI MARUs.

1 November 1943:
CH-31 departs Roi, Kwajalein with torpedo boat HIYODORI, and auxiliary subchaser CHa-6 escorting damaged fleet oiler SHIRETOKO under tow by MOMOGAWA MARU in a convoy for Sasebo via Truk consisting of small cargo ships TAKUNAN and CAROLINE MARUs.

E 7 November 1943:
Arrives at Truk. CH-31 is detached.

24 November 1943:
CH-31 and CH-29 and destroyer URAKAZE arrive at Truk's South Channel escorting a convoy of four unidentified ships.

11 December 1943:
At 1000, CH-31 departs Yokosuka with kaibokan OKI and patrol boat PB-46 escorting convoy No. 3211A consisting of MITAKESAN and HAKOZAKI MARUs.

14 December 1943:
HAKOZAKI MARU is detached for Chichi-Jima with engine trouble.

15 December 1943:
At 1100, CH-31 and CH-30 depart Truk escorting convoy No. 1152 consisting of JUZAN and HARUNA MARUs.

19 December 1943:
W of Cape Matanalem, New Hanover. At 1235, the convoy is attacked by unidentified bombers at 02-41N, 148-57E, but they are driven off and inflict no damage.

20 December 1943:
At 1500, arrives at Rabaul.

28 December 1943:
At 1500, Lt Fukase Eijiro’s CH-31 departs Truk for Kwajalein with CH-30 escorting a convoy consisting of SHOHO and HOKUJO MARUs.

31 December 1943:
Eastern Carolines. At about noon, LtCdr James D. Grant's USS GREENLING (SS-213) torpedoes and sinks transport SHOHO MARU at 05-18N, 160-20E. GREENLING evades 18 depth-charges in counterattacks by the escorts.

1 January 1944:
At 0940, CH-31 arrives at Kusaie.

2 January 1944:
At 0745, departs Kusaie.

4 January 1944:
Arrives at Kwajalein. HOKUJO MARU is detached.

16 January 1944:
CH-31 conducts an ASW sweep, then departs Ponape for Truk with destroyers SUZUKAZE and URAKAZE escorting convoy No. 6163 consisting of NICHIRAN, RYOYO and MATSUE MARUs.

19 January 1944:
At 0730, arrives at Truk.

13 February 1944:
Departs Truk for Yokosuka with kaibokan MANJU and OKI escorting convoy No. 4212 consisting of fleet oiler NOTORO, fleet supply ship IRAKO and TATSUURA and HIBI MARUs.

27 February 1944:
Arrives at Yokosuka.

10 March 1944:
At 0528, CH-31 departs Saipan for Truk with CH-28 and auxiliary minesweepers No. 2 FUMI MARU and SEKI MARU escorting convoy 3310 consisting of TOYOKAWA and SEITO MARUs. After departure, the convoy's destination is changed to Palau.

15 March 1944:
Arrives at Palau.

24 March 1944:
At 0700, CH-31, CH-17 and CH-32 departs Saipan with destroyers NOWAKI and ASAKAZE, kaibokan MANJU and minelayer KYOSAI escorting convoy HIGASHI MATSU No. 2 (return) consisting of fleet supply ship SOYA and TAKUNAN, NACHI, AWA (ex-WAWA), DAITEN, MIHO, BINGO, RYUKA, TAKAOKA, HIBI, TAMAHOKO, TATSUHARU and SHINFUKU MARUs and an unidentified ship.

1 April 1944:
At 1000, the convoy arrives at Tokyo.

4 May 1944:
At 1400, CH-31, CH-32 and CH-52 depart Tateyama with destroyers ASANAGI, MINATSUKI, torpedo boat OTORI, kaibokan OKI, CD-24 and auxiliary subchaser SHONAN MARU No. 8 escorting convoy 3503 consisting of KEIYO, HAKOZAKI, HIYORI (NICHIWA), ENOSHIMA, MINO, OSAKA, TAIKOKU, FUKKO, TATSUTAGAWA, SHINFUKU, FUKUKOKU, KOHO, KOJUN and SHUNSEN MARUs.

10 May 1944:
420 miles NW of Saipan. At 1743, LtCdr Russell Kefauver’s USS TAMBOR (SS-198) torpedoes and damages KEIYO MARU at 19-27N 140-00E.

14 May 1944:
Arrives at Saipan.

16 May 1944:
At 1630, CH-31 and CH-32 depart Saipan for Palau escorting a convoy consisting of FUKKO, NICHIWA, TAIKOKU and OSAKA MARUs.

17 May 1944:
At about 0030, LtCdr Malcolm E. Garrison's USS SANDLANCE (SS-381) torpedoes and sinks TAIKOKU MARU. That same day, at 1840, LtCdr John A. Scott's USS TUNNY (SS-282) torpedoes and sinks NICHIWA MARU. At 2120, Garrison's SANDLANCE strikes again and torpedoes and sinks FUKKO MARU. OSAKA MARU is ordered back to Saipan.

E 18 May 1944:
Arrives at Saipan.

3 June 1944:
At 1600, CH-31 departs Truk with kaibokan CD-6, subchasers CH-20, CH-32 and CH-51 and uxiliary subchaser CHa-66 escorting a convoy consisting of MOJI, IMIZU, TATSUTAGAWA, KOJUN MARUs, and oilers NITCHO, KYOEI and NANKO MARU No. 1 and 13 other unidentified ships.

7 June 1944:
At 1140, arrives at Saipan.

12 July 1944:
CH-31 departs Manila for Zamboanga with patrol boat PB-105 (ex-Philippine Customs Cruiser ARAYAT) and auxiliary subchaser CHa-84 escorting convoy C-124 consisting of MAYA, TATEISHI, SHIROUMA (HAKUBA) and NATSUKAWA MARUs.

14 July 1944:
At 1050. arrives at Cebu and departs later that day.

16 July 1944:
At 1800, LtCdr William C. Thompson's USS CABRILLA (SS-288) unsuccessfully attacks an unknown tanker. The escorts counter-attack and drop 24 depth charges that slightly damage CABRILLA.

17 July 1944:
At 0230, CABRILLA torpedoes and sinks MAYA MARU. Thompson also torpedoes and damages NATSUKAWA MARU.

18 July 1944:
Arrives at Zamboanga. That same day, CH-31 is reassigned to the 3rd Southern Expeditionary Fleet.

21 August 1944:
At 0850, CH-31 and CH-46 depart Zamboanga for Jolo, Philippines with patrol boat PB-105 and minesweeper W-28 escorting convoy H-33 consisting of MEXICO and HAVRE MARUs.

24 August 1944:
Arrives at Jolo.

27 August 1944:
CH-31 and CH-46 depart Jolo for Menado, Celebes with PB-105 and minesweeper W-28 escorting convoy H-33 consisting of MEXICO and HARVE MARUs.

29 August 1944:
N of Celebes. At 0225, LtCdr Arthur E. Krapf's USS JACK (SS-259) makes a radar-assisted surface attack on the convoy. Krapf torpedoes and sinks MEXICO MARU at 02-15N, 122-29E. She takes down 847 men of the almost 4,300 troops and crew she was carrying and a cargo of food, munitions, oil and gasoline in barrels.

At about 0400, Krapf makes another surface attack on the convoy. He fires nine torpedoes by radar bearings of which three hit and sink minesweeper W-28 at 02-15N, 123-29E. No counterattacks are made and JACK safely departs the scene.

25 October 1944:
At 0650, CH-31, CH-5 and patrol boat PB-2 depart Tarakan escorting convoy M-246 consisting of UNKAI MARU No. 12, CAROLINE MARU and oilers TAKASAGO MARU No. 2, NANSHIN MARU No. 8, NANKO MARU No. 1 and HORAI MARU No. 7 At 1437 that day, UNKAI MARU No. 12 runs aground. Patrol boat PB-2 is detached to guard the ship.

29 October 1944:
Arrives at Honda Bay, N of Puerto Princesa. Later that day, UNKAI MARU No. 12 and patrol boat PB-2 rejoin the convoy at Puerto Princesa.

31 October 1944:
At 2000, arrives at Taytay Bay, NE Palawan.

1 November 1944:
Departs Taytay Bay. Later that day, the convoy is attacked by LtCdr George H. Laird's USS BLACKFIN (SS-322) and LtCdr William T. Kinsella's RAY (SS-271). At 0923, Laird torpedoes and sinks UNKAI MARU No. 12 and CAROLINE MARU, both at 12-57N, 120-12E. At 1042, Kinsella sinks HORAI MARU No. 7 at the same location. Later that day, the rest of the convoy arrives at Manila.

4 December 1944:
At 0800, CH-31 and CH-30 depart Singapore for Manila with kaibokan CD-43 and patrol boat PB-103 (Ex-USS FINCH, AM-9) escorting convoy SHIMA RINJI consisting of SHOEI, KOSHIN and EIHO MARUs and KYOEI MARU No. 3.

8 December 1944:
NNE of Kuching, Borneo. At 0104, either LtCdr John C. Martin's USS HAMMERHEAD (SS-364) or LtCdr Joseph P. FitzPatrick's PADDLE (SS-263) torpedoes and sinks SHOEI MARU with a cargo of 5,000-tons of gasoline at 04-02N, 111-12E.

12 December 1944:
At 1300, arrives at Kuching.

13 December 1944:
At 1200, departs Kuching.

16 December 1944:
KOSHIN MARU suffers engine trouble and has to be towed to Miri.

18 December 1944:
Arrives at Cape Paloh.

19 December 1944:
Arrives at Pentengu.

23 December 1944:
At 1400, departs Pentengu. At about 2300, that same day, off Kuching, LtCdr Irvin S. Hartman's BARBERO (SS-317) torpedoes and sinks subchaser CH-30 at 02-42N, 111-05E.

11 January 1945:
At 1100, CH-31 departs Cape St Jacques with kaibokan CD-35, CD-43, patrol boat No. 103 and minesweeper W-101 escorting convoy SATA-05 consisting of KENSEI and TOYU MARUs, Landing Ship Transport T-149 and tankers AYAYUKI, KOSHIN and EIHO MARUs. In the evening, T-149 finds the heavy seas too dangerous. She is detached from the convoy and returns to St Jacques.

12 January 1945: Operation "Gratitude"- Task Force 38's Strikes on Indochina:
Off Cape Paderan, Indochina. Aircraft of Vice Admiral John S. McCain's Task Force 38 attack SATA-05 and sink the entire convoy including CH-31.

10 March 1945:
Removed from the Navy List.

---

-Bob Hackett, Sander Kingsepp and Peter Cundall

---

Back to Subchaser Page