KUSENTEI!

© 2005-2006 Bob Hackett, Sander Kingsepp and Peter Cundall

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1942:
Tamano. Laid down at the Mitsui Engineering & Shipbuilding shipyard.

18 May 1942:
Launched and numbered CH-33.

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

September 1942:
Assigned to the Yokosuka Guard Unit. Patrols Tokyo Bay and escorts convoys in the Aomori, Iwate, and Miyagi Prefecture areas.

March 1943:
Reassigned to the 4th Base Force at Truk. Escorts convoys between Truk and Palau.

20 April 1943:
At 1200, CH-33 departs Truk escorting a convoy to Palau consisting of MEITEN and SANSEI MARUs and oiler KYOEI MARU.

26 April 1943:
At 0800, arrives at Palau.

5 August 1943:
At 0400, CH-33 departs Kwajalein escorting convoy 6053 making 11.5 knots and consisting of SANTOS, MITAKESAN and KAISHO MARUs.

9 August 1943:
At 1100, arrives at Truk's north channel.

2 September 1943:
At 0600, CH-33 departs Palau for Wewak, New Guinea escorting convoy "Wewak No. 8" consisting of TENKAI MARU No. 1 and SHINSEI MARU.

5 September 1943:
At 1312, TENKAI MARU No. 1 is hit by one of four torpedoes fired by LtCdr (later Captain) Frank M. Parker's USS SWORDFISH (SS-193). TENKAI MARU No. 1, carrying a cargo of ammunition, gasoline and automobiles, is set afire and at 1420 sinks at 01-10N, 142-10E. CH-33 counterattacks and drops 10 depth charges, but SWORDFISH escapes.

7 September 1943:
Arrives at Wewak.

8 October 1943:
At 0600, oiler SHINSHU MARU and CH-33 depart Truk by the western entrance.

6 November 1943:
At 0600, CH-33 escorts SHOTAN MARU through Truk's South Passage into the lagoon. At 1600, Naval tanker ONDO and CH 33 depart Truk by S channel. Later that day, CH-33 is detached and diverted to assist tanker GENYO MARU and destroyer YAKAZE that collided.

17 November 1943:
At 0950, CH-33 and auxiliary subchaser CHa-27 and destroyer AMATSUKAZE depart Palau escorting convoy 8175 consisting of oilers TSURUMI, SATA, SEIAN MARU, KYOEI MARUs and cargo ship SHOYU MARU. About 1400, an unidentified submarine is detected. The escorts conduct an unsuccessful depth charge attack.

20 November 1943:
At 2000, CHa-27 detaches and returns to Palau.

24 November 1943:
At 0840, arrives at Truk.

27 November 1943:
At 0600, CH-33 and torpedo boat OTORI depart Truk escorting fleet convoy 1272 to Palau consisting of KONEI and HAGURO MARUs.

1 December 1943:
At about 0715, KONEI MARU is hit by three of six torpedoes fired by LtCdr (later Rear Admiral) William T. Nelson's USS PETO (SS-265). KONEI MARU sinks at 01-16N, 146-45E. CH-33 and OTORI counterattack and drop 12 depth charges, but PETO evades undamaged.

4 December 1943:
At 1135, arrives at Rabaul.

6 December 1943:
At midnight, CH-33 and CH- 29 depart Rabaul escorting convoy 2063 consisting of HAKUSAN, KOKAI and TETSUYO MARUs.

9 December 1943:
At 0945, TETSUYO MARU develops engine trouble and falls behind. CH-33 is detached to escort.

10 December 1943:
At 0650, the convoy arrives at Truk.

22 December 1943:
At 0830, CH-33 departs Truk to Palau escorting fleet convoy 7222 consisting of KYOEI and SHINSHU MARUs.

27 December 1943:
Arrives at Palau at 1400 after weathering bad storms at sea.

31 December 1943:
At 1800, CH-33 joins convoy 2614 at sea. The convoy departed Balikpapan, Borneo on 26 December and consists of OGURA MARU No. 3 escorted by patrol boat No. 2.

E 30 December 1943:
CH-33 escorts convoy O-706 consisting of SHIRANESAN, RYUA, HARUNA, HOKKAI and HIDAKA MARUs and KOSHU MARU No. 3, also escorted by CH-39. [1]

3 January 1944:
At 0730, CH-33, CH-24 and CH-39 depart Palau escorting convoy 8031 consisting of oiler OGURA MARU No. 3.

9 January 1944:
Arrives at Truk.

20 January 1944:
CH-33, CH-24, CH-30 and CH-39 depart Truk escorting a convoy consisting of oiler OGURA MARU No. 3.

24 January 1944:
CH-33 and destroyer SUZUKAZE depart Truk for Eniwetok escorting a convoy consisting of OKITSU and NIPPO MARUs.

25 January 1944:
N of Ponape. At 2305, SUZUKAZE is hit and sunk by two torpedoes fired by LtCdr (later Cdr) George G. Molumphy's old USS SKIPJACK (SS-184). CH-33 commences an unsuccessful search for the submarine, then rescues survivors while OKITSU and NIPPO MARUs clear the area.

26 January 1944:
LtCdr Molumphy again attacks the convoy and, at 0305, he hits OKITSU MARU in hold No. 4. She floods and begins sinking by the stern. Abandon Ship is ordered. At 0340, OKITSU MARU sinks at 09-24N, 157-45E taking down 176 men.

10 February 1944:
Lt Abe Takao's CH-33 arrives at Truk escorting a convoy consisting of NIPPO, YUBAI and KITAGAMI MARUs with TAKUNAN MARU No. 2 and SHONAN MARU No. 5.

17-18 February 1944: American Operation "Hailstone" - The Attack on Truk:
Beginning at dawn, Vice Admiral (later Admiral) Marc A. Mitscher’s Task Force 58's five fleet carriers and four light carriers, supported by six battleships, ten cruisers and 28 destroyers, launch air attacks on airfields, shore installations and ships in the lagoon. Mitscher launches 30 strikes of at least 150 aircraft each. The strikes are launched about every hour.

In two days of raids, Task Force 58 sinks 31 transports and 10 naval vessels (two cruisers, four destroyers and four auxiliary vessels, destroys nearly 200 aircraft and damages severely about 100 more. Truk is eliminated as a major fleet anchorage for the IJN. CH-33 is damaged in the raid.

6 March 1944:
At 1130, CH-33 departs Truk escorting convoy 4304 consisting of URAKAMI, SHIRANE, JUZAN and AWAJI MARUs also escorted by kaibokans AMAKUSA and MIKURA and minesweeper W-21.

10 March 1944:
At 1222, arrives at Saipan.

April 1944:
LtCdr Kuwahara Tadao assumes command from Lt Abe.

29 May 1944:
At dawn, CH-33, CH-17, CH-50 and torpedo boat OTORI depart Tokyo escorting convoy 3530 consisting of TAKAOKA, SHINROKU, TAMAHIME, KASHIMASAN, HAVRE, SUGIYAMA, KATSUKAWA, KATORI MARUs and two other unidentified ships carrying troops of the 43rd Infantry Division.

4 June 1944:
At 1530, KATSUKAWA MARU is torpedoed and sunk by LtCdr (later KIA) Edward N. Blakely's USS SHARK (SS-314) at 19-45N, 138-15E.

5 June 1944:
At 1645, at 18-40N, 140-35E, TAKAOKA MARU is torpedoed and sunk by Blakely's SHARK followed immediately afterwards by TAMAHIME MARU sunk in the same position also by SHARK.

6 June 1944:
At 1000, LtCdr (later Admiral, CINCPACFLT) Bernard A. Clarey's USS PINTADO (USS-387) torpedoes and sinks KASHIMASAN MARU at 16-28N, 142-16E. At 1010, Clarey sinks HAVRE MARU in the same position.

7 June 1944:
SUGIYAMA MARU is torpedoed and damaged by LtCdr (later Captain) James B. Grady's USS WHALE (SS-239) at 31-06N, 142-34E and returns to Yokosuka. Later that day, the remaining ships arrive at Saipan.

11 June 1944:
Fear of an imminent Allied landing causes all navigable ships in Saipan to flee. At 0400, CH-33, CH-55, auxiliary submarine chasers CHa-20, CHa-50, auxiliary minesweeper Wa-6, torpedo boat OTORI and kaibokan CD-4 depart escorting makeshift convoy 4611 consisting of MOJI, FUKOKU, BATAVIA, TENRYUGAWA, TATSUTAGAWA, KOKKO, IMIZU, SHINTO, HINKO, BOKUYO, KEIYO, NITCHO, REIKAI, INARI MARUs and 16 other unidentified ships.

12-14 June 1944:
Vice Admiral (later Admiral) Marc A. Mitscher’s Task Force 58 launch attacks on the Marianas from 15 fleet and light carriers in preparation for invasion landings on Saipan.

Aircraft from TG 58.4’s ESSEX (CV-9), LANGLEY (CVL-27) and COWPENS (CVL- 25) sink torpedo boat OTORI, auxiliary netlayer KOKKU MARU, transports BATAVIA, HINKO, KAMISHIMA, IMIZU, NITCHO, REIKAI and TENRYUGAWA MARUs, cargo ship BOKUYO MARU, IJA cargo ships FUKOKU and MOJI MARUs and merchant TSUSHIMA MARU. Mitscher’s planes damage transport TATSUTAKAWA MARU, kaibokan CD-4, subchasers CH- 33, CH-50 and CH-51, auxiliary subchaser Cha-20 and auxiliary minesweeper Wa-6.

June-July 1944:
Undergoes repairs.

August 1944:
Reassigned to the Southwest Area Fleet.

11 August 1944:
At 2100, CH-33 and CH-30 depart Manila escorting the Miri leg of convoy MI-13 that consists of SHOEI, HIYORI, KUNIYAMA, URAL, SHINSEI MARU No.1, HIGANE MARUs and oilers SHINCHO, SHINPO, ZUIYO, TEIKON, OGURA MARU No. 2, TOKUWA, KYOEI and ATAGO MARUs also escorted by kaibokan CD-4, and Patrol Boat No. 38.

12 August 1944:
At 0730, Cdr Frank G. Selby's USS PUFFER (SS-268) torpedoes and sinks SHINPO MARU at 13-18N, 120-11E. At 0733, Selby torpedoes and sinks TEIKON MARU at the same location. The convoy shelters in Paluan Bay, NW Mindoro.

14 August 1944:
At 0700, departs Paluan Bay.

16-17 August 1944:
CH-33 splits off and joins the escort of convoy MI-12 that left Miri at 0700 on 16 August consisting of TAKETOYO, NORFOLK, UGA, KINRYU, GYOKUYO, JUNGEN GO, GYOSAN MARU and an unknown ship called KAITO MARU and oilers ZUIYO, SEISHIN and NANSEI MARUs escorted by kaibokan SHIMUSHU, CD-16, CD-28 and subchasers CH-30 and CH-41. [1]

18 August 1944:
At 1352, LtCdr (later Rear Admiral-Ret) William T. Kinsella's USS RAY (SS-271) torpedoes and sinks NANSEI MARU at 08-39N, 116-39E The convoy is ordered to seek shelter.

20 August 1944:
At 1930, arrives at Paluan Bay, NW Mindoro.

21 August 1944:
At 0556, departs Paluan Bay. Soon after kaibokan CD-28 attacks an enemy submarine contact. At 0720, a wolfpack consisting of USS RAY, GUITARRO, HADDO, HARDER and MUSKALLUNGE begin the first of a series of successful attacks. At 0720, LtCdr Kinsella's RAY torpedoes and sinks TAKETOYO MARU at 13-23N, 120-19E. At 0730, LtCdr (later Rear Admiral-Ret) Chester W. Nimitz Jr's HADDO (SS-255) torpedoes and sinks NORFOLK MARU in the same position. At 0800, Nimitz torpedoes and sinks KINRYU MARU at 13-20N, 120-17E. At 0825, LtCdr (later Captain) Enrique D. Haskins GUITARRO (SS-363) torpedoes and sinks UGA MARU at the same location.

22 August 1944:
At 2200, arrives at Manila.

6 September 1944:
At 0748, destroyer SATSUKI, CH-33 and CH-30 depart Singapore in the Kamoi convoy consisting of Naval oiler KAMOI and oilers KYOKUTO and OKIGAWA MARUs.

7 September 1944:
SATSUKI and CH-33 detach to carry out an anti-submarine sweep.

8 September 1944:
At 0325, rejoins convoy. At 1030, OKIGAWA MARU and CH-33 detach for Miri. At 1858, the rest of the convoy arrives at Miri.

9 September 1944:
At 0722, CH-28, CH-30 and CH-33 and destroyer SATSUKI depart Miri escorting a revised convoy consisting of KYOKUHO and KYOKUTO MARUs. Thirty minutes after leaving, KYOKUHO MARU suffers engine problems and returns to port. At 1117, CH-28 returns to Miri. At 1903, the convoy anchors in Brunei Bay.

10 September 1944:
At 1252, departs Brunei Bay.

11 September 1944:
At 1945, arrives at Culusian Bay.

12 September 1944:
At 0640, departs Culusian Bay. At 1842, arrives at Boayan Island, NW Palawan. Delayed there on orders.

19 September 1944:
At 0652, departs Boayan Island. At 1845, arrives at Talampulan Island, Busuanga.

20 September 1944:
At 0617, departs Talampulan Island. Arrives at Manila at 2122.

21 September 1944:
During a major carrier air raid on Manila, KYOKUTO MARU is sunk, but CH-33 escapes serious damage.

6 October 1944:
At 0618, CH-33, CH-28, CH-30 and CH-41 depart N San Fernando as part of the escort of combined convoys MATA-28 and MIMA-11 consisting of KOHOKU, HOKUREI, BUNZAN, SHOEI, HOKUSEN, TERUKUNI, HISHIGATA, OMINE and oilers TACHIBABA, KAMOI, SHINYO MARU No. 8 and YAMAMIZU MARU No. 2 escorted by kaibokans CD-8, CD-25 and CD-32 and minesweeper W-20.

At about 0800, LtCdr Henry C. Stevenson's USS ASPRO (SS-309) attacks the convoy. Stevenson fires three torpedoes by periscope at an oiler and claims one hit, but actually achieves no results. At 1530, LtCdr William C. Thompson's USS CABRILLA (SS-288) torpedoes HOKUREI MARU and YAMAMIZU MARU No. 2. YAMAMIZU MARU No. 2 sinks at 17-30N, 120-9E. HOKUREI MARU, badly damaged, is beached off Vigan. The convoy seeks shelter in Lapoc Bay, arriving at 1830. [3]

7 October 1944:
At 0030, the rest of convoy departs except for TERUKUNI, OMINE and SHINYO MARU No. 8 and probably CH-33 and CH 30 that remain behind at Lapoc Bay.

27 October 1944:
At 1958, CH-33 and CH-30, auxiliary subchaser CHa-41 and minesweeper W-20 depart Hong Kong escorting convoy HOMA-01 consisting of HAMBURG, YASUKUNI, SHINETSU and KANSHU MARUs, NISSHO MARU No. 18 and oiler EIWA MARU.

30 October 1944:
CH-33 arrives at Takao escorting SHINETSU MARU separately from the rest of the convoy.

23 November 1944:
At 1200, CH-33, patrol boats Nos. 38 and 102 (ex-USS STEWART, DD-224) depart Manila for Takao escorting convoy MATA-34 consisting only of MANJU MARU.

24 November 1944:
Luzon Strait, 100 miles N of Cape Engano. LtCdr (later Rear Amiral/COMSUBPAC) John H. Maurer’s submerged USS ATULE (SS-403) sights a transport and three escorts heading NW toward Sabtang Island. At dark, Maurer surfaces and sets course so as to intercept the transport shortly after midnight.

25 November 1944:
At about 0125, as Maurer is setting up on the transport, one of her escorts also moves into periscope view. He fires six bow tubes at the overlapping targets, then turns the boat about and fires his two stern tubes. ATULE scores two hits on each target. Patrol boat No. 38 (ex-DD YOMOGI) disintegrates. MANJU MARU is hit aft in hold No. 5 and goes dead in the water.

ATULE withdraws as CH-33 and patrol boats No. 102 search the area. At 0516, MANJU MARU sinks by the stern at 20-14N, 121-40 E. Twenty-four of her crew and about 700 of 1300 troops on board are KIA.

3 December 1944:
Departs Takao in convoy TAMA-34 consisting of JINYO, KENJO, YAMAKUNI, FUKUYO and YASUKUNI MARUs, BANSHU MARU No. 31 and SHINPUKU MARU escorted by destroyer KURETAKE, kaibokan CD-28, CD-54 and CH-33 as well as two unidentified escorts.

6 December 1944:
At 2147, a concerted wolfpack attack begins by Cdr (later Rear Admiral) Roy M. Davenport's USS TREPANG (SS-412) and LtCdr James D. Fulp's SEGUNDO (SS-398).

Davenport torpedoes and sinks JINYO MARU at 18-30N 121-57E with 1430 lives lost, mostly troops. At 2237, Fulp torpedoes YASUKUNI MARU that runs aground and is later abandoned near 18-59N 120-56E. At 2358 Davenport hits FUKUYO MARU with three torpedoes. She blows up and sinks nearby. BANSHU MARU No. 31 is also sunk with no survivors around this time at 18-54N, 120-49E.

7 December 1944:
At 0005, Fulp's SEGUNDO torpedoes and sinks KENJO MARU at 18-52N, 121-57E. YAMAKUNI MARU, damaged by Davenport's TREPANG, goes no further than N San Fernando.

9 December 1944:
SHINPUKU MARU arrives at Manila with escorts less kaibokan CD-54 that is detached to rescue YASUKUNI MARU .

5 March 1945:
Convoy HI-88I departs Singapore for Moji with six merchants, escorted by CH-33, CH-9, one unidentified escort, ASW detection vessel TATEISHI (fitted with special cable to detect submerged subs) and auxiliary subchaser KAINAN MARU.

19 March 1945:
Convoy HI-88J departs Singapore consisting of seven merchants including NASHIN, FUSHIMI and HOSEN MARUs and MOTOYAMA MARU No. 1 and TAKASAGO MARU No. 6 escorted by destroyer AMATSUKAZE, kaibokans MANJU, CD-1, CD-18, CD-26, CD-33, CD-84, CD-130, CD-134, subchasers CH-8, CH-9, CH-20, CH-33, cable-layer TATEISHI and auxiliary subchaser KAINAN MARU.

20 March 1945:
50 miles S of Camranh Bay, Indochina. At about 0100, convoy HI-88J is attacked by LtCdr Benjamin C Jarvis' BAYA (SS-318). Jarvis torpedoes and sinks merchant KAINAN MARU. CH-9 counterattacks BAYA and drops 21 DCs .

That same afternoon, at about 1720, the convoy is attacked by LtCdr (later Cdr) William H. Hazzard's USS BLENNY (SS-324). Hazzard torpedoes and sinks small oilers NASHIN and HOSEN MARUs.

21 March 1945:
Off Nha Trang, Indochina. Convoy HI-88J is attacked by Fifth Air Force B-25 "Mitchell" medium-bombers of the 345 Bomb Group that bomb, strafe and sink CH-33, cargo vessels MOTOYAMA MARU No. 1 and FUSHIMI MARU. The B-25's also damage CH-9, small oiler TAKASAGO MARU NO. 6 and cable-layer TATEISHI.

One B-25 is lost. Four crewmembers are captured. One dies of injuries. Later, the Japanese decapitate the other three crewmen.

10 May 1945:
Removed from the Navy List.

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[1] Some sources show GYOKUYO MARU as OYO MARU.

-Bob Hackett, Sander Kingsepp and Peter Cundall.

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