SOKAITEI!

© 2005-2015 Bob Hackett and Peter Cundall

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1943:
Tokyo. Laid down at Ishikawajima Shipbuilding.

1943:
Launched and numbered W-30.

10 January 1944:
Reserve Lt Kubota Rokuzo (former CO of converted gunboat EDO MARU) is appointed the Chief Equipping Officer.

5 February 1944:
Completed and commissioned in the IJN. Reserve Lt Kubota Rokuzo is the Commanding Officer. At 1530 departs Ishikawajima yard and at 1600 arrives at Yokosuka.

8 February 1944:
At 1435 departs Yokosuka and anchors in Tokyo Bay before departing the area.

10 February 1944:
Arrives at Saiki.

17 February 1944:
At 0600 departs Saiki and at 1600 arrives at Hiroshima Wan.

18 February 1944:
At 0800 departs Hiroshima Wan and at 2130 arrives at Abe Shima.

19 February 1944:
At 0745 departs Abe Shima and at 2100 arrives at Uzuki Wan.

20 February 1944:
At 0745 departs Uzuki Wan and at 1400 arrives at Saiki.

22 February 1944:
At 0800 departs Saiki and at 2000 arrives back at Uzuki.

23 February 1944:
At 0700 departs Uzuki and at 2100 arrives at Kure.

24 February 1944:
At 0815 departs Kure and at 1510 arrives at Saiki.

26 February 1944:
At 0900 departs Saiki and at 1730 arrives at Saiki.

29 February 1944:
At 1700 departs Kure.

1 March 1944:
At 0840 arrives at Mutsure and at 1635, W-30 departs Mutsure for Takao, Formosa with destroyer AMAGIRI escorting convoy MOTA-07 consisting of TEIKA (ex French CAP VARELLA), KUNIKAWA, YAMAHAGI, KONSAN, CHIYODA, SUGIYAMA, KENSEI, SARAWAK, HAKUROKU (HAKUSHIKA), RIKKO, ATAGO and NITTATSU MARUs.

3 March 1944:
At 0910 the convoy arrives at Yamakawa and departs at 1522. At 1710 arrives at Kagoshima.

4 March 1944:
MAESHIMA and destroyer ASAGAO join the escort of convoy MOTA-07 and transport LONDON MARU and tanker NISSHIN MARU and one unidentified merchant ship (from MOTA-05). At 1154 the convoy departs Kagoshima. At some point KUNIKAWA MARU detaches from the convoy and romps ahead arriving at Takao a day earlier than the convoy.

7 March 1944:
HAKUROKU MARU falls behind with engine problems, but later catches up at 1620.

8 March 1944:
YAMAHAGI, HAKUROKU and TEIKA MARUs are detached for Kirun (Keelung), Formosa (Taiwan).

9 March 1944:
At 1220 arrives at Takao.

13 March 1944:
At 1030 W-30 departs Takao escorting convoy TAMA-11 consisting of KONSAN, TOYOOKA, SUGIYAMA MARUs and three unidentified merchant ships.

16 March 1944:
At 0805 a torpedo attack is successfully avoided.

17 March 1944:
At 1750 arrives at Manila.

20 March 1944:
At 0630, W-30 departs Manila for Kau Bay, Halmahera Island, Moluccas with torpedo-boat HAYABUSA escorting convoy H-22 consisting of KUNIKAWA, SHINKYO, ATLAS, ANSHU, TOYOOKA, BENGAL, KURAMASAN and MITO MARUs.

23 March 1944:
Zamboanga Sea. At about 1530, auxiliary subchaser KYO MARU No. 12 joins the escort and W-30 is detached.

25 March 1944:
At 0830 W-30 arrives at Davao.

1 April 1944:
At 0045 departs Davao with torpedo boat HAYABUSA, submarine chaser CH-46 and minesweeper W-5 escorting the first part of remains of convoy H-22, a total of three vessels from a pool consisting of ATLAS, ANSHU, TOYOOKA, KURAMASAN and MITO MARUs. (The balance and HINO MARU No. 1, the latter also acting as an auxiliary minesweeper sailed on 7 April)

3 April 1944:
At 1730 arrives at Kau.

4 April 1944:
At 1045 departs Kau and at 1310 arrives at Wasile.

5 April 1944:
At 1130 departs Wasile escorting convoy M-16 consisting of CHINKAI and TOYO MARUs. At 1910 the torpedo boat HAYABUSA joins the convoy.

7 April 1944:
At 0400 a surfaced submarine is sighted in 05-25N 136-17E but avoided. At 2035 arrives at Davao. W-30 is detached.

8 April 1944:
At 1748 W-30 departs Davao.

9 April 1944:
At 1845 arrives at Zamboanga.

10 April 1944:
At 1755 departs Zamboanga with auxiliary TOKO MARU No. 1 GO. Over the next few days carries outt a series of patrols landing Army troops at particular locations.

11 April 1944:
At 1555 arrives at Cagayan.

12 April 1944:
At 0300 departs Cagayan and at 1857 arrives at Surigao.

13 April 1944:
At 0700 departs Surigao and at 1037 arrives at Melgar and departs there at 1528. At 1708 arrives back at Surigao.

14 April 1944:
At 0610 departs Surigao and at 1905 arrives at Masapelid.

15 April 1944:
At 0450 departs Masapelid and at 0530 arrives at Gigaquit. At 1355 departs Gigaquit.

17 April 1944:
At 0855 arrives at Mate.

18 April 1944:
At 0620 departs Mate and at 1448 arrives at Davao.

22 April 1944:
At 0219 departs Davao escorting KIYOKAWA MARU. At 1650 KIYOKAWA MARU suffers an engine breakdown.

23 April 1944:
At 0019 KIYOKAWA MARU is able to resume the journey under her own power.

25 April 1944:
At 1110 arrives at Balikpapan.

27 April 1944:
At 1102 departs Balikpapan escorting Naval oiler ASHIZURI.

28 April 1944:
At 1832 arrives at Tarakan.

29 April 1944:
At 2250 departs Tarakan still escorting ASHIZURI.

1 May 1944:
At 1115 arrives at Balikpapan.

4 May 1944:
At 0740 departs Balikpapan escorting Naval oiler SHIOYA.

6 May 1944:
At 1425 arrives at Davao.

9 May 1944:
At 0940 departs Davao still escorting SHIOYA.

10 May 1944:
At 1050 arrives at Zamboanga and departs there at 1600.

11 May 1944:
At 1340 arrives at Cebu.

14 May 1944:
At 0621 departs Cebu still escorting SHIOYA.

16 May 1944:
At 1635 arrives at Balikpapan.

23 May 1944:
At 0729 departs Balikpapan escorting Naval tanker SHIOYA and possibly tanker NASUSAN MARU initially.

24 May 1944:
At 0920, USN codebreakers intercept and decrypt a message from the CO of fleet oiler SHIOYA that reads: “From one hour commencing at 0713 we attacked an enemy submarine with the cooperation of planes in position 01-45N, 121-04E.” [1]

25 May 1944:
At 1445 arrives at Davao.

27 May 1944:
At 1954 departs Davao.

28 May 1944:
At 1654 returns to Davao.

2 June 1944:
At 2126 departs Davao escorting Navy Landing Ship Transport T-127 as part of Operation "KON" - The Relief of Biak. The first Biak relief transport force consists of CruDiv 16's cruiser AOBA, light cruiser KINU, minelayers ITSUKUSHIMA and TSUGARU, Navy Transport T-127, several freighters, DesDiv 19's SHIKINAMI, URANAMI, DesDiv 27's SHIGURE and subchasers CH-36 and CH-37.

3 June 1944:
At 0900 minelayer ITSUKUSHIMA joins as an additional escort. At 1915 arrives at Sarangani. Meanwhile other elements of the KON force are sighted by two B-24 bombers. That evening, the operation is temporarily canceled.

4 June 1944:
At 1948 departs Sarangani still in convoy.

5 June 1944:
At 1412 arrives at Tahuna Bay and departs there at 1624. Meanwhile Headquarters, Combined Fleet reinstates Operation KON.

6 June 1944:
At 1004 arrives at Davao.

7 June 1944:
At 1225 departs Davao with minelayer TSUGARU.

9 June 1944:
At 2010 arrives at Sarawatoe Island anchorage.

10 June 1944:
At 0835 departs Sarawatoe anchorage still escorting TSUGARU.

11 June 1944:
At 1606 arrives at Kau.

12 June 1944:
At 1227 departs Kau escorting TSUGARU.

13 June 1944:
At 1148 arrives at Sorong and departs at 1508. At 1935 arrives at Sarawatoe western anchorage.

14 June 1944:
At 1031 departs Sarawatoe and at 1409 arrives at Sorong.

15 June 1944:
At 1145 anchored off Sorong, attacked by a B-25 and P-38 without damage.

16 June 1944:
At 1224 departs Sorong with TSUGARU.

17 June 1944:
At 1025 arrives at Obit.

19 June 1944:
At 0825 departs Obit with Navy Landing Ship Transport T-127 towing four Daihatsu barges.

20 June 1944:
At 1758 arrives at Sarawatoe anchorage.

21 June 1944:
At 0800 TSUGARU arrives at the anchorage and departs at 0900. At 0938 the ships depart Sarawatoe and at 1300 meet up with TSUGARU. At 2327 arrive at Sorong.

22 June 1944:
At 0434 W-30 and T-127 depart Sorong and at 0705 arrive at Merchesa Bay, Batanta Island, Dampier Straits. At 1300 submarine chaser CH-36 arrives.

23 June 1944:
At 1338 all ships depart Merchesa Bay and at 1553 arrives at Sorong.

24 June 1944:
At 0507 departs Sorong with submarine chaser CH-36 and at 0711 arrives at Merchesa Bay. At 1353 departs Merchesa Bay with submarine chaser CH-36 and at 1605 arrives back at Sorong.

25 June 1944:
At 0423 departs Sorong and at 0732 arrives at Merchesa Bay. At 1321 departs Merchesa Bay and at 1612 arrives at Samate.

26 June 1944:
At 0456 departs Samate and at 0727 arrives at a nearby bay, departing at 1309. At 1620 arrives at Jeroman Island and departs there at 1808 and arrives at Sorong at 1853.

27 June 1944:
At 0116 CH-36, T-127 and W-30 departs Sorong and at 0933 arrive at Kabui Bay, Waigeo Island. At 1554 depart.

28 June 1944:
At 1123 W-30, submarine chaser CH-36 and Navy Landing Ship Transport T-127 arrive at Wasile.

30 June 1944:
At 0802 W-30 and CH-36 depart Wasile and at 0843 arrives at Hatetabako. At 1002 depart Hatetabako and at 1518 arrive at Bore.

1 July 1944:
At 0400 W-30, submarine chaser CH-36 and Navy Landing Ship Transport T-127 depart Bore (near Kau) for Davao.

2 July 1944:
At 1350 arrives at Davao.

5 July 1944:
At 0804 departs Davao.

6 July 1944:
At 1420 arrives at Malusu Bay, Basilan Island.

7 July 1944:
At 0726 departs Malusu Bay. At 1355 returns to Malusu Bay.

8 July 1944:
At 0726 departs Malusu Bay and at 1815 arrives at Jolo.

9 July 1944:
At 0650 departs Jolo and at 1802 arrives back at Malusu Bay.

10 July 1944:
At 0725 departs Malusu Bay and at 1650 arrives at Zamboanga.

17 July 1944:
At 1520 departs Zamboanga and meets up with with patrol boat PB-103 and auxiliary subchaser MOGAMI MARU escorting NATSUKAWA MARU that has been damaged earlier that day by LtCdr William C. Thompson's (USNA ’35) USS CABRILLA (SS-288). At 2038 arrives back at Zamboanga.

18 July 1944:
At 0541 departs Zamboanga escorting tankers TSURUMI and HISHI MARU No. 2 also escorted by submarine chasers CH-49 and CH-58 and auxiliary netlayer TOKO MARU No 1 GO. At 1925 arrives at Malusu Bay, Basilan Island.

19 July 1944:
At 0600 departs Malusu Bay and at 1832 arrives at Lebak Bay.

20 July 1944:
At 0552 departs Lebak Bay and later that day at 1823 arrives at Glan.

21 July 1944:
At 0457 departs Glan and at 1905 arrives at Malalag.

22 July 1944:
At 0624 departs Malalag and at 1048 arrives at Davao.

25 July 1944:
At 0155, W-30 departs Davao for Zamboanga, Philippines with kaibokan CD-6, CD-16, subchasers CH-49, CH-58, auxiliary subchaser KYO MARU No. 12, auxiliary netlayer TOKACHI MARU, auxiliaries TOKO MARU and HIYODORI MARU No. 2 escorting convoy Z-258 consisting of AZUCHISAN, OYO, TATSUHARU, RYUKA and KITAGAMI MARUs and HISHI MARU No. 2, KYOEI MARU No. 2 and LST No. 127. The convoy is provided air cover.

27 July 1944:
At about 0100, LtCdr (later Captain) Bladen D. Claggett's (USNA ’35) USS DACE (SS-247) attacks the convoy and sinks tanker KYOEI MARU No. 2. Five crewmen are KIA. The escorts counterattack and drop 20 depth-charges, all unsuccessfully. At about 1400, the convoy is attacked by aircraft in the Pilas Channel, but suffers no damage. At 1830, the convoy arrives at Zamboanga.

30 July 1944:
At 0600 departs Zamboanga with auxiliary submarine chaser CHa-11 escorting TATEISHI MARU. At 1837 arrives at Igat Bay.

31 July 1944:
At 0543 departs Igat Bay. At 1843 arrives at Lebak Bay.

1 August 1944:
At 0600 departs Lebak Bay and at 1653 arrives at Glan.

2 August 1944:
At 0552 departs Glan and at 1900 arrives at Davao still escorting TATEISHI MARU.

5 August 1944:
At 0148, W-30 departs Davao for Zamboanga with auxiliary subchasers CHa-11 and KYO MARU No. 12 escorting the "TSURUMI convoy" consisting of Fleet oiler TSURUMI and cargo ships BINGO and OSEI MARUs.

S of Mindanao. At 1113, TSURUMI is attacked by LtCdr (later Captain) Edward F. Dissette’s (USNA ’34) USS CERO (SS-225) at 05-53N, 125-41E. In an underwater attack, Dissette fires six torpedoes and claims four hits. At 1130, TSURUMI capsizes and sinks in Davao Gulf. W-30 may also have suffered damage. The convoy reverses course back to Davao.

On 11 August FRUMEL provided the following information based from an intercepted message from W-30:
"Minesweeper No. 30 reported oiler TSURUMI torpedoed in 5-53N, 125-41E at 1113 on 5 August and in danger of sinking."

W-30 herself was apparently not damaged.

6 August 1944:
At 1704 the convoy arrives back at Davao.

7 August 1944:
SHINSEI MARU joins the convoy that is renamed the "BINGO MARU" convoy. At 0853, the convoy departs Davao.

8 August 1944:
At 0830 minesweeper W-30 arrives at 06-05N 124-23E, the sinking scene of IJA transport YAMATAMA MARU (4642 grt) carrying 1,650 soldiers from Manila and begins an anti submarine sweep. Later auxiliary subchaser KYO MARU No. 12 arrives at the scene and joins the anti submarine sweep.

9 August 1944:
At 0007 arrives at Malalag, Davao Gulf. Subchaser CH-33 joins the escort. At 0726 W-30 departs Malalag and arrives at Davao at 0954 and departs at 1408 arriving back at Malalag at 1949. CH-33 appears to have been detached at this point.

11 August 1944:
At 0552 the convoy departs Malalag. SHINSEI MARU is detached at 1800.

12 August 1944:
At 0354 departs Glan. RYUKA MARU joins the convoy.

13 August 1944:
At 1800, arrives at Zamboanga.

16 August 1944:
At 0925 departs Zamboanga escorting tanker HISHI MARU No. 12 with auxiliary submarine chaser CHa-15 and KYO MARU No. 12. Between 1230 and 1330 HISHI MARU No. 2 suffers an engine breakdown.

18 August 1944:
At 1835 arrives at Malalag.

19 August 1944:
At 0553 departs Malalag and at 0922 arrives at Davao. At 1722 departs Davao and at 1753 arrives off Samal Island.

20 August 1944:
At 0654 departs Samal Island and at 0725 arrives at Davao. At 1623 departs Davao and at 1700 arrives back at Samal Island.

21 August 1944:
At 0652 departs Samal Island and at 0722 arrives at Davao. At 1603 departs Davao and at 1844 arrives at Malalag.

22 August 1944:
At 0339, tanker HISHI MARU Maru No. 2 departs Malalag, Davao Gulf with transport TATEISHI MARU in convoy Z-222 escorted by minesweeper W-30, auxiliary subchaser CHa-15, KYO MARU No. 12 and auxiliary netlayer TOKACHI MARU. At 0851, the convoy is attacked by an enemy submarine, probably USS FLYING FISH (SS-229), but its three torpedoes miss. The escorts counter-attack and drop 26 depth-charges without effect. At 1819, the convoy anchors at Glan, Sarangani Bay, southern Mindanao.

23 August 1944:
At 1915, departs Sarangani Bay.

24 August 1944:
At 0304, an American plane snoops the convoy. At 0430, it attacks KYO MARU No. 12, but causes no damage. At 1915, convoy Z-222 arrives at Zamboanga, Mindanao.

1 September 1944:
Departs Zamboanga in convoy with tanker HISHI MARU No. 2 and CAROLINE MARU escorted by minesweeper W-30. Later that day arrives at Jolo.

2 September 1944:
Departs Jolo and later that day arrives at Bongao.

3 September 1944:
Departs Bongao and later that day arrives at Trusan Ligitan.

4 September 1944:
Departs Trusan Ligitan and later that day arrives at Taraka

14 September 1944:
At 1149 W-30 departs Balikpapan with patrol boat PB-2 escorting Navy oiler SHIRETOKO and Navy transport T-131.

20 September 1944:
At 1849 arrives at Bongao, Tawi Tawi.

22 September 1944:
At 0620 departs Bongao with patrol boat PB-2 escorting Naval oiler SHIRETOKO.

24 September 1944:
At 0627 anchors off Puerto Princesa. The ships are held there because of a large air-raid on Manila, the intended destination.

27 September 1944:
At 1750 departs Puerto Princesa for Manila but the damger of air attack forces the ships to return.

28 September 1944:
At 1732 arrives back at Puerto Princesa.

30 September 1944:
At 0454 departs Puerto Princesa to Taytay Bay, NE Palawan.

3 October 1944:
Arrives at Manila.

6 October 1944:
At 0929 PB-2 and Minesweeper No.30 depart Manila escorting Shiretoko Convoy consisting of Naval Oiler SHIRETOKO and tanker KYOEI MARU.

7 October 1944:
NW of Manila. At 0334, LtCdr (later Cdr) James A. Adkins' (USNA ’26) USS COD (SS-224) attacks SHIRETOKO by SJ radar. He fires four torpedoes on radar bearings and range and gets two hits at 13-30N, 119-20E. Later that day at 1706, arrives at Busuanga anchorage and stays there carrying out urgent repairs for the next five days.

12 October 1944:
At 0450 departs Busuanga. Later that day at 1713, arrives at Taytay Bay.

13 October 1944:
At 0525 departs Taytay Bay. Later that day, arrives at Puerto Princesa, Palawan Islands.

16 October 1944:
Departs Puerto Princesa. Later that day, arrives at Brookes Point.

17 October 1944:
Departs Brookes Point. Later that day, arrives at Banggi Island.

18 October 1944:
CH-56 joins the convoy as escort. Later that day, tanker SHUNTEN MARU and minesweeper W-105 also join the convoy. At 0602 departs Banggi Island.

19 October 1944:
At 2117 arrives at Kudat.

20 October 1944:
At 0642 departs Kudat. Later that day at 1734, arrives at Turtle Island.

21 October 1944:
At 1252 departs Turtle Island.

22 October 1944:
At 1712 arrives at Tarakan.

24 October 1944:
At 0655 W-30, W-17 and W-18 depart Miri escorting tanker NICHINAN MARU No. 2.

26 October 1944:
At 1943 arrives at Bacuit Bay. Later that day auxiliary submarine chaser URUPPU MARU joins the convoy as an additional escort.

27 October 1944:
At 0654 departs Bacuit Bay.

28 October 1944:
At 0725 arrives at Manila.

9 November 1944:Operation "TA No. 3" - The Reinforcement of Leyte:
In the early dawn, reinforcement convoy TA No. 3 departs Manila consisting of CELEBES, TAIZAN (ex-British ST. QUENTIN), MIKASA, SAIHO and TENSHO MARUs escorted by destroyers SHIMAKAZE, HAMANAMI, HATSUHARU, TAKE, W-30 and subchaser CH-46. The convoy is carrying 4,000 men, 6,000-tons of munitions and heavy equipment of the IJA's 26th Division to Leyte.

10 November 1944:
Sibuyan Sea. CELEBES MARU runs hard aground on outlying reefs of Luzon's Bondoc Peninsula and is left behind. CH-46 is detached to guard her until the homeward-bound TA No. 4 could remove her troops and crew.

11 November 1944:
As the convoy enters Ormoc Bay, Leyte, it is attacked by a total of 347 aircraft from Rear Admiral (later Vice Admiral) Alfred E. Montgomery's (USNA ’12) (former CO of USS RANGER, CV-4) TG 38.1, Rear Admiral (later Vice Admiral) Frederick C. Sherman’s (USNA ’10) (former CO of USS LEXINGTON, CV-2) TG 38.3 and Rear Admiral (later Vice Admiral) Ralph E. Davison's TG 38.4's.

The planes sink Lt Kubota's W-30, destroyers HAMANAMI(63 sailors KIA), NAGANAMI (156 sailors KIA), SHIMAKAZE (F) (losses are uncertain but Rear Admiral (Vice Admiral posthumously) Hayakawa Mikio (44) is KIA) and WAKATSUKI (losses are uncertain but Captain (Rear Admiral posthumously) Suzuki Yasuatsu (49) is KIA) and cargo ships MIKASA (72 crewmen and 47 troops KIA), SEIHO (86 crewmen and 44 troops KIA), TENSHO (76 crewmen and many troops KIA) and TAIZAN (65 crewmen and many troops KIA) MARUs at 10-50N, 124-31E. Of the 4,000 troops carried on the four transports only about 500 survive. American planes strafe and kill the survivors wading ashore who otherwise would still be able fighting men.

10 January 1945:
Removed from the Navy List

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Authors' Notes: :
[1] According to CNO analysts, W-30 was in company with SHIOYA.

Thanks go to John Whitman of the USA for info on CNO intercepts of Japanese messages and to Mr. Gilbert Casse of France and Mr Sander Kingsepp of Estonia for general assistance. Thanks also to Mr. Matthew Jones of Mississippi, USA for help in identifying the CO's. Special thanks go to Hans Mcilveen of the Netherlands for info on FRUMEL intercepts.

Photo credit goes to Gakken via J. Ed Low.

-Bob Hackett and Peter Cundall.

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