IJN Minesweeper W-4:
Tabular Record of Movement

© 2005-2013 Bob Hackett and Peter Cundall

Revision 6

1 December 1923:
Laid down at the Sasebo Navy Yard.

24 April 1924:
Launched and numbered W-4.

29 April 1925:
Completed and registered in the Yokosuka Naval District.

1 November 1928:
Lt (later RAdm) Murakami Chonosuke (44)(former gunnery officer of SAWAKAZE) is appointed the Commanding Officer.

3 October 1929:
An unknown officer is appointed Commanding Officer.

12 December 1930:
Lt (RAdm, posthumously) Kawano Yasushi (47)(former navigator of HAKAZE) is appointed the Commanding Officer.

1 December 1931:
Lt (RAdm, posthumously) Inoue Yoshio (48)(former navigator of SAGIRI) is appointed the Commanding Officer.

15 November 1935:
Lt (RAdm, posthumously) Kotaki Hisao (50)(former navigator of SEITO) is appointed the Commanding Officer.

1 December 1936:
An unknown officer is appointed Commanding Officer.

28 July 1938:
LtCdr Tomita Sutezo (51)(former CO of W-6) is appointed the Commanding Officer.

15 December 1938:
An unknown officer is appointed Commanding Officer.

1 November 1941:
Assigned to Vice Admiral Ozawa Jisaburo's (37) South Expeditionary Fleet in Rear Admiral (later Vice Admiral) Hiraoka Kumeichi's (39) (former CO of HIEI) 9th Base Force, both based at Camranh Bay, Indochina.

8 November 1941:
Departs Kure.

17 November 1941:
Arrives at Sana (now Ya Xian), Hainan island and conducts patrols.

1 December 1941:
At 1400 departs Sana.

E 3 December 1941:
Arrives at Camranh Bay, Indochina.

5 December 1941:
At 0053 W-2, W-3 and W-4 arrive at Pulo Condore. At 2350 W-2 and W-3 depart.

6 December 1941:
At 0400 W-4 departs Pulau Condore.

8 December 1941:
At 0100, arrives off Singora, Siam (Thailand). Departs there at 1808. Thereafter, supports the invasion.

10 December 1941:
At 1935 arrives at Camranh Bay.

13 December 1941:
At 0830 departs Camranh Bay.

16 December 1941:
At 0958 arrives at Singora and departs from there at 1132.

19 December 1941:
At 2316 arrives at Singora.

20 December 1941:
At 0903 departs Singora.

24 December 1941:
At 0936 arrives at Singora.

12 January 1942:
At 0925 departs Singora.

13 January 1942:
At 1754 arrives at Pulo Condore.

20 January 1942:
W-1, W-3, and W-4 departs Camranh escorting 11 troop transports with DesDiv 11's FUBUKI, HATSUYUKI and SHIRAYUKI, DesDiv 20's ASAGIRI, AMAGIRI and YUGIRI.

22 January 1942:
The convoy arrives at Singora.

23 January 1942:
At 0955 departs Singora.

26 January 1942:
At 0840 the convoy arrives at Endau, Malaya.

27 January 1942: The Battle off Endau:
Singapore. LtCdr B. S. Davies' old WW1 destroyer HMS THANET and LtCdr W. T. A. Moran's HMAS VAMPIRE are dispatched to make a night attack on the troop tansports at Endau, about 80 miles N of Singapore. At 0237, approaching Endau, they engage a warship they take to be a destroyer, but actually is W-4. HMAS VAMPIRE launches two torpedoes at W-4, but they miss. W-4 raises the alarm. The Allied destroyers continue towards Endau.

vAt about 0400, HMS THANET is hit in the engine and boiler rooms. Her speed falls off and an explosion wrecks the old destroyer. She goes dead in the water, lists heavily to starboard and begins to sink. HMAS VAMPIRE lays a smoke screen, but HMS THANET is attacked by destroyers FUBUKI, HATSUYUKI, ASAGIRI, AMAGIRI, YUGIRI and W-4. At 0415, HMS THANET sinks. HMAS VAMPIRE is undamaged and without casualties, but she has no chance to pick up survivors. She makes for Singapore arriving there at 1000.

Troop transports KANSAI MARU and CANBERRA MARU are damaged in the action. Later, destroyer SHIRAYUKI picks up 31 survivors from HMS THANET. They are never seen again.

At 1700 W-4 departs Endau.

January 1942:
Kaibokan SHIMUSHU receives a signal from Vice Admiral Ozawa Jisaburo's (37) First Southern Expeditionary Fleet's flagship CHOKAI that orders the kaibokan to locate the wreck of British battleship HMS PRINCE OF WALES sunk off Kuantan, Malaya by IJN aircraft on 10 December.

29 January 1942:
South China Sea, E of Malaya. SHIMUSHU, escorted by minesweepers W-4, W-1, W-2, W-3 and W-5, locates the wreck of British battlecruiser HMS REPULSE and marks it with a buoy. At 1218 W-4 arrives at Anambas Islands.

1 February 1942:
SHIMUSHU reports locating the wreck of HMS PRINCE OF WALES at a depth of 60 meters. The site is marked with a buoy and the IJN ships are recalled.

2 February 1942:
Assigned to escort the Bangka-Palembang, Sumatra invasion force.

9 February 1942: Operation "L" - The Invasions of Palembang and Banka Island:
MineSweepDiv 1's minesweepers W-4, W-1, W-2, W-3 and W-5 and SubChasDiv 11's CH-7 and CH-8 depart Camranh Bay, Indochina for Palembang escorting eight transports. Rear Admiral (later Vice Admiral) Hashimoto Shintaro's (41) DesRon 3's light cruiser SENDAI with DesDiv 11's FUBUKI, HATSUYUKI and SHIRAYUKI, DesDiv 20's ASAGIRI provides close cover.

11 February 1942:
W-1, W-3 and W-4 escort eleven transports of the invasion force.

16 February 1942:
The transports land troops near Palembang.

18 February 1942: Operation "J" - The Invasion of Java, Netherlands East Indies:
W-4 is in Rear Admiral (later Vice Admiral) Hirose Sueto's (39) (former CO of AOBA) 2nd Base Force's in Cdr (Rear Admiral, posthumously) Amano Shigetaka's (47)(former CO of KAGERO) MinesweepDiv 1 with W-1, W-2, W-3 and W-5 of Vice Admiral Takahashi Ibo's (36) Third Fleet, Southern Force, Netherlands East Indies Force.

28 February 1942: The Battle of the Sunda Strait:
USS HOUSTON (CA-30) and Australian cruiser HMAS PERTH sortie for Tjilatjap via the Sunda Strait.

Bantam Bay. 27 transports land the main body of the IJA's 2nd Infantry Division. At 2215, HOUSTON and PERTH attack the Japanese troop transports that are screened only by destroyers HARUKAZE, HATAKAZE and FUBUKI and MineSweepDiv 1's W-1, W-2, W-3 and W-4. The escorts make smoke to mask the transports. FUBUKI charges and launches a salvo of torpedoes at USS HOUSTON and HMAS PERTH.

At 2300, the IJN’s Western Support Force's MIKUMA and MOGAMI, destroyer SHIKINAMI, Third Escort Force's light cruiser NATORI and destroyers SHIRAKUMO, MURAKUMO, SHIRAYUKI, HATSUYUKI and ASAKAZE arrive and engage HOUSTON and PERTH with gunfire and torpedoes.

1 March 1942:
At 0108, torpedoes strike both USS HOUSTON and HMAS PERTH. At 0142, HMAS PERTH sinks at 05-51-42S, 106-07-52E. At 0135, torpedoes fired by MOGAMI sink W-2 and sink or disable transports SAKURA, HORAI, TATSUNO and RYUJO (SHINSHU) MARUs, the latter carrying LtGen Imamura Hitoshi, Commander-in-Chief of the invading 16th Army. Imamura jumps into the sea, but survives. One crewman is lost from SAKURA MARU, and 38 passengers (mainly men unloading the ship) and 18 crewmen are killed on HORAI MARU with casualties for the other ships unknown. At 0142, HMAS PERTH sinks at 05-51-42S, 106-07-52E. At 0206, USS HOUSTON sinks at 05-48-45S, 106-07-55E.

2 March 1942:
At 2305 W-4 enters Bantan Bay.

3 March 1942:
At 0755 W-4 departs Bantan Bay.

5 March 1942:
At 2011 arrives at Singapore.

8 March 1942:
At 0800 MinesweepDiv 1 and DesRon 3's DesDiv 10 and DesDiv 20 depart Singapore escorting four invasion transport ships to Sabang and Koetaradja, Sumatra.

12 March 1942: Operation "T" - The Seizure of North Sumatra:
Sweeps for mines and covers troop landings at Kutaradja and Sabang.

15 March 1942:
At 1300 arrives at Penang.

19 March 1942:
MineSweepDiv 1's W-1, W-3 and W-4 and SubChasDiv 91's CHOKO MARU and SHONAN MARU Nos. 5 and 7 are assigned to the No. 2 Escort Unit comprised of light cruiser KASHII (F), escort SHIMUSHU, minelayer HATSUTAKA, destroyers of DesRon 3 and 5 and the 9th Base Force's gunboat EIKO MARU. The No. 2 Escort Unit departs Singapore escorting 32 transports carrying the IJA's 56th Infantry Division.

20 March 1942: Operation “D” – The Seizure of the Andaman Islands.
At 0800 W-4 departs Penang. Later sweeps for mines in the Andaman Islands area in support of the invasion landings.

23 March 1942:
At 0200 arrives at Port Blair, Andamans.

25 March 1942: Operation “U” – The Seizure of Rangoon, Burma.
The transports begin landing troops at Rangoon.

28 March 1942:
Arrives at Penang.

30 March 1942:
Departs Penang.

1 April 1942:
Strait of Malacca. Off Pulau Perak, Malaya. Empty transports YAE MARU and SHUNSEI MARU are torpedoed and sunk by Royal Navy Lt Cdr Hugh A.V. Haggard's submarine HMS TRUANT. Two gunners and four crewmen of YAE MARU, and two crewmwn on SHUNSEI MARU are killed. HMS TRUANT escapes a counterattack by the escort. Arrives at Singapore later that day.

3 April 1942:
Arrives at Singapore.

8 April 1942:
Seletar Naval Base, Singapore. Drydocked.

1 May 1942:
Undocked. Conducts mine sweeping in the Singapore area.

20 May 1942:
Assigned to the Yokosuka Naval District.

25 May 1942:
Departs Seletar. Escorts a convoy.

7 June 1942:
At 1400 W-1, W-3, W-4 and W-5 departs Mako escorting convoy No. 220 consisting of SHINYO MARU (4163 gt) and eleven unidentified merchant ships.

11 June 1942:
Arrives at Mutsure. W-3 and W-5 detach en route and both arrive at Sasebo at 1700.

12 June 1942:
Patrols near the Okuma archipelago. At 1400 W-1 and W-4 arrives at Sasebo.

23 June 1942:
At 0800 W-1, W-3, W-4 and W-5 all depart Sasebo on ASW patrol. At 1700 all four minesweepers arrive at Tamanoura, near Nagasaki.

26 June 1942:
At 0800 W-1 and W-4 depart Tamanoura.

3 July 1942:
At 0745 W-1 and W-4 arrive back at Sasebo.

5 July 1942:
At 1700 W-1 and W-4 depart Sasebo.

15 July 1942:
Attached to the Osaka patrol unit with W-1, W-3 and W-5. Patrols in the Kii Straits.

17 July 1942:
At 1240 W-4 arrives alone at Yuranai.

8 August 1942:
At 0700 W-1, W-3, W-4 and W-5 all depart Yuranai.

10 August 1942:
At 1420 W-1 and W-3 arrive back at Yuranai. At 1450 W-4 and W-5 also arrive back at Yuranai.

27 August 1942:
At 0630 W-1, W-3, W-4 and W-5 depart Yuranai, all arriving at Osaka between 1145 and 1203.

31 August 1942:
Reassigned to the Sasebo Naval District.

1 September 1942:
At 0800 W-1, W-3, W-4 and W-5 all depart Osaka together.

2 September 1942:
Between 1655 (W-5), 1713 (W-3), 1714 (W-4) and 1715 (W-1) all arrive back at Sasebo.

8 September 1942:
At 0800 W-1, W-3 and W-4 depart Sasebo. Patrols the Okuma strait area.

17 September 1942:
At 1138 W-4 arrives alone back at Sasebo.

18 September 1942:
At 1800 W-3, W-4 and W-5 depart Sasebo. W-1 follows 5 minutes later.

20 September 1942:
Between 1236 and 1310 all four minesweepers arrive back at Sasebo.

21 September 1942:
At 0800 W-4 and W-5 both depart Sasebo.

27 September 1942:
At 1920 W-4 alone arrives at Sasebo.

28 September 1942:
At 0830 W-4 and W-5 both depart Sasebo.

29 September 1942:
At 1530 and 1532 respectively W-5 and W-4 arrive back at Sasebo.

5 October 1942:
At 1409 W-5, followed at 1425 by W-4, depart Sasebo. Patrols the Goto archipelago area.

13 October 1942:
Between 1515 and 1604 W-1, W-3, W-4 and W-5 all arrive back at Sasebo.

1 November 1942:
At 1206 W-5 departs Sasebo, followed three minutes later by W-4.

6 November 1942:
Between 1420 and 1452 W-1, W-3, W-4 and W-5 all arrive at Sasebo.

7 November 1942:
Between 1608 and 1613 W-1, W-3, W-4 and W-5 all depart Sasebo.

9 November 1942:
At 1510 W-4 arrives alone at Sasebo.

11 November 1942:
At 0800 W-4 and W-5 depart Sasebo.

12 November 1942:
At 1448 W-4 arrives back alone at Sasebo.

16 November 1942:
At 0830 W-1 and W-4 depart Sasebo, returning there at 1630.

17 November 1942:
At 0830 W-1 and W-4 depart Sasebo again.

18 November 1942:
At 1600 W-1 arrives back at Sasebo, followed at 1608 by W-4.

21 November 1942:
At 0800 W-1 and W-4 depart Sasebo.

23 November 1942:
At 1530 W-1 arrives back at Sasebo, followed at 1546 by W-4.

24 November 1942:
At 0730 W-1 and W-4 both depart Sasebo.

27 November 1942:
At 1700 and 1703 respectively, W-1 and W-4 arrive back at Sasebo.

30 November 1942:
At 0830 W-1 and W-4 depart Sasebo.

5 December 1942:
At 0917 W-4 arrives at Sasebo, followed at 0930 by W-1.

7 December 1942:
At 0800 W-4 departs Sasebo, followed at 0845 by W-1.

9 December 1942:
Between 1217 and 1335 W-1, W-3, W-4 and W-5 all arrive at Sasebo.

15 December 1942:
At 0800 W-1 and W-4 both depart Sasebo.

20 December 1942:
At 1445 W-1 arrives back at Sasebo, followed at 1514 by W-4.

22 December 1942:
At 0800 W-1 and W-4 depart Sasebo.

30 December 1942:
At 1445 W-4 arrives back at Sasebo, followed at 1500 by W-1.

3 January 1943:
At 0830 W-1 and W-4 depart Sasebo.

7 January 1943:
At 0900 W-1 and W-4 arrive back at Sasebo.

8 January 1943:
At 0800 W-1 departs Sasebo, followed at 0829 by W-4.

14 January 1943:
At 1520 W-4 arrives at Sasebo.

16 January 1943:
At 1200 W-4 departs Sasebo.

17 January 1943:
At 0530 W-4 arrives briefly back at Sasebo, departing again at 0943.

19 January 1943:
At 1424 W-4 arrives at Sasebo, followed at 1428 by W-5.

21 January 1943:
At 0625 W-5 departs Sasebo, followed at 0651 by W-4.

22 January 1943:
Between 1540 and 1645 W-1, W-3, W-4 and W-5 all arrive at Sasebo.

27 January 1943:
At 0800 (except W-5 at 0758) W-1, W-3, W-4 and W-5 all depart Sasebo.

5 February 1943:
At 1449 arrives at Sasebo.

12 February 1943:
At 1700 W-3, and at 1706 W-4, both depart Sasebo.

23 February 1943:
At 1630 W-4 and W-5 both arrive back at Sasebo.

28 February 1943:
At 0700 departs Sasebo and later that day at 1610 arrives at Miike.

2 March 1943:
At 0300 departs Miike.

11 March 1943:
At 1415 arrives at Sasebo.

15 March 1943:
At 0800 W-1 departs Sasebo, followed at 0829 by W-4 and at 0830 by W-5. Both W-1 and W-5 return to port at 1600.

27 March 1943:
At 1425 arrives at Sasebo.

30 March 1943:
At 0800 W-4 departs Sasebo but returns at 1500.

1 April 1943:
Reassigned to the Yokosuka Naval District.

6 April 1943:
Arrives Tokyo Bay escorting convoy No.8404 consisting of LONDON, FUKUYAMA and SHISEN MARUs.

8 April 1943:
Departs Yokosuka.

23 April 1943:
Departs Yokosuka. Escorts convoy No. 7423 between Yokosuka and Kobe consisting of TATSUTAGAWA, KIYOTADA (SEICHU), KIZUGAWA and RYUKO MARUs.

27 April 1943:
Arrives back at Tokyo Bay escorting convoy No. 8427 consisting of KOSHIN, SHOZUI, BUZAN MARUs and TOYO MARU No.1

4 May 1943:
Yokosuka. Drydocked.

8 June 1943:
Undocked. Departs Yokosuka. Conducts mine sweeping in the Toba area.

2 July 1943:
Departs Yokosuka. Escorts a convoy between Yokosuka and Muroran.

8 July 1943:
Off Sanriku Bight, NE Honshu. At 0936 (K), LtCdr Harry B. Dodge's USS SEAL (SS-183) fires three torpedoes at a 5,000-ton freighter in a three-ship convoy and misses. An Aichi E13A1 "Jake" patrol floatplane from the Yamada Bay detachment, escorting the freighter, attacks the submarine at 0940 with two depth bombs. W-1, escorting the same convoy, joins the hunt at 0944, dropping two depth charges.
Another E13A1 patrolling in that area spots an oil slick, moving north. Its pilot alerts W-4 and the auxiliary minesweeper MISAGO MARU No. 1, who chase the submarine until 1213. As a result of damage received in the course of several successive attacks, USS SEAL is forced to terminate her seventh war patrol.

July 1943:
Lt Kobayashi Masao is appointed Commanding Officer.

3 September 1943:
Departs Rabaul in convoy 2032 consisting of KIYOSUMI and TOKYO MARUs also escorted by submarine chaser CH-28 and minelayer SOKUTEN. At some point into the journey SOKUTEN is apparently detached.

6 September 1943:
At 0930, W-4 and CH-28 arrive at Kimishima Channel, Truk escorting the convoy.

1 December 1943:
Reassigned to Vice Admiral (Admiral, posthumously) Yamagata Seigo's (39)(former CO of ARIAKE) 4th Southern Expeditionary Fleet's Special Base Force 26.

21 December 1943:
At 1230 W-4 and W-5 depart Yokosuka.

23 December 1943:
At 0745 arrives at Kure.

25 December 1943:
At 0700 W-4 and W-5 depart Kure.

26 December 1943:
At 1030 both arrive at Moji.

29 December 1943:
At 1500, W-4 , W-5 and destroyer ASAGAO depart Moji for Takao, Formosa escorting convoy No. 125 consisting of KOSHIN, TEIHOKU (ex French PERSEE), YAMAMIYA, KANAN, KENZUI, KAZUURA, MISAKI, SEINAN and HOREI MARUs, SHINYO MARU No. 8 and tanker KYOEI MARU No. 5.

4 January 1944:
At 0932, arrives at Takao.

6 January 1944:
At 0902, W-4, W-5 depart Takao to Manila and Halmahera Island, Moluccas escorting Rinji (Special) convoy "S" consisting of SEINAN, KOSHIN, YAMAMIYA and KAZUURA MARUs.

7 January 1944:
At 1057, W-4's cutter is damaged by heavy waves.

9 January 1944:
At 1000, arrives at Manila. SEINAN, KOSHIN and KAZUURA MARUs leave the convoy.

12 January 1944:
At 0952 W-4 and W-5 depart Manila for Halmahera escorting convoy H-13 consisting of YAMAMIYA and KAZUURA MARUs and SHINSEI MARU No. 5.

17 January 1944:
At 0704, arrives at Davao. SHINSEI MARU No. 5 leaves the convoy.

19 January 1944:
At 0900 departs Davao.

21 January 1944:
At 1230 arrives at Wasile, Halmahera.

25 January 1944:
At 1300 W-4 and W-5 departs Wasile escorting RAIZAN MARU.

27 January 1944:
At 1600 arrives at Ambon.

30 January 1944:
At 1915 W-4 and W-5 depart Ambon and meet up with a convoy consisting of CELEBES, CHUKA, ASAKA and YAMABUKI MARUs. The minelayer ITSUKUSHIMA which is escorting the convoy apparently detaches at this point or sometime after.

31 January 1944:
At 1600 W-4 and W-5 and the convoy arrive at Ambon.

1 February 1944:
At 2000 departs Ambon.

3 February 1944:
At 0800 arrives at Ternate and departs from there at 1830.

4 February 1944:
At 0930 arrives at Kau Bay.

6 February 1944:
At 1345 departs Kau Bay and meets up with inbound H convoy consisting of FUSO, MIZUHO, WALES and SEATTLE MARUs.

8 February 1944:
At 1330 arrives at Wasile and at 1442 returns to Kau Bay.

14 February 1944:
At 1400, W-4 and patrol boat PB-105 depart Halmahera for Manila escorting convoy M-12 consisting of MIZUHO, FUSO, MITSUKI, KENWA, TONEGAWA, KUROGANE and WALES MARUs.

16 February 1944:
At 0145, KENWA MARU is attacked unsucessfully by a submarine, probably by LtCdr (later Captain) Henry G. Munson's (USNA ’32) USS CREVALLE (SS-291). At 2000, W-4 is detached from the convoy at 05.00N 128.35E. 17 February 1944: At 03.45N 128.10E W-4 meets up with NAGATA MARU.

18 February 1944:
At 0945 W-4 arrives back at Kau.

29 February 1944:
At 0733 departs Ternate escorting NORWAY MARU.

1 March 1944:
At 1800 arrives at Kau Bay.

5 March 1944:
At 1730 departs Wasile.

6 March 1944:
At 2300 returns to Wasile.

9 March 1944:
At midnight, W-4 and auxiliary netlayer HINOKI MARU depart Halmahera for Manokwari, New Guinea escorting a convoy consisting of TENCHO, SHOGEN, YAMAGATA and SHINYU MARUs.

11 March 1944:
At 1017, arrives at Manokwari.

20 March 1944:
W-4 and HINOKI MARU depart Manokwari escorting a convoy consisting of YAMAGATA and SHINYU MARUs to Biak Island and Sarmi, New Guinea.

25 March 1944:
At 1100 arrives at Sarmi. Later proceeds to Wakde.

26 March 1944:
Departs Wakde and later that day arrives at Sarmi.

29 March 1944:
At 0400, the convoy departs Sarmi for Manokwari.

31 March 1944:
At 1916, arrives at Manokwari.

3 April 1944:
At 0500, W-4 , W-105, HINOKI MARU and auxiliary NITTO MARU No. 17 depart Manokwari for Halmahera escorting TENCHO, SHOGEN, YAMAGATA, SHINYU and TETSUYO MARUs and an unidentified ship.

5 April 1944:
At 0625, arrives at Wasile, Halmahera.

11 April 1944:
At 0330 departs Wasile probably escorting a convoy consisting of TENSHO and ROKKO MARUs.

12 April 1944:
At 1700 arrives at Sorong.

13 April 1944:
At 0526, W-4 departs Sorong, New Guinea for Manokwari escorting a convoy consisting of TENSHO and ROKKO MARUs.

16 April 1944:
At 1100 arrives at Manokwari.

19 April 1944:
At 0555, W-4 and minelayer WAKATAKA depart Manokwari for Halmahera escorting a convoy consisting of ANSHU and TENSHO MARUs.

23 April 1944:
Arrives at Wasile, Halmahera Island.

27 April 1944:
At 1800 departs Wasile with minelayer WAKATAKA escorting ANSHU MARU and probably TENSHO MARU.

30 April 1944:
At 1200 arrives at Manokwari.

30 May 1944:
At 1810, W-4 and minelayer AOTAKA depart Wasile, Halmahera for Zamboanga, Mindanao escorting a convoy consisting of ETAJIMA, TOUN, TAIYU, KURAMASAN and ROKKO MARUs and SHINSEI MARU No. 1.

2 June 1944:
At 1810 arrives at Zamboanga.

7 June 1944:
At 0200 departs Zamboanga and at 2000 arrives Davao.

10 June 1944:
At 0600 departs Davao with submarine chaser CH-26 escorting SHINSEI MARU.

13 June 1944:
At 1500 arrives at Kau.

15 June 1944:
At 0300 departs Kau with submarine chaser CH-26, auxiliary NITTO MARU No. 18 and auxiliary minesweeper WA-105 escorting KOHOKU, BUNZAN and RYOCHI MARUs. That evening arrives at Teluk Buli.

16 June 1944:
W-4 and NITTO MARU No. 18 depart Teluk Buli with KOHOKU MARU. The other two ships and escorts head for Sorong.

19 June 1944:
At 1430 arrives at Ambon.

26 June 1944:
Escorts a convoy between Ambon and Davao consisting of a single Naval merchant ship. At 0800 departs Ambon escorting DAICHO MARU.

30 June 1944:
At 1900 arrives at the west mouth of the Tioro Straits.

1 July 1944:
At 0700 departs Tioro Straits.

3 July 1944:
At 1400 arrives at Macassar.

5 July 1944:
At 1300 departs Macassar.

10 July 1944:
At 1700 arrives at Surabaya.

14 July 1944:
Departs Surabaya.

16 July 1944:
Arrives at Batavia (now Jakarta), Java. Undergoes repairs.

August 1944:
Lt Takamura Noboru is appointed Commanding Officer.

15 September 1944:
Repairs are completed.

1 October 1944:
Reassigned to the 1st Southern Expeditionary Fleet in the 10th Special Base Force at Singapore.

3 October 1944:
Arrives at Singapore.

1 December 1944:
Arrives at Singapore. Thereafter, conducts patrols, performs minesweeping and escorts convoys.

10 December 1944:
Departs Singapore.

14 December 1944:
Arrives at Singapore.

21 December 1944:
Departs Singapore.

25 December 1944:
Arrives at Jakarta.

29 December 1944:
Departs Jakarta.

31 December 1944:
Arrives at Singapore.

6 January 1945:
Departs Singapore.

12 January 1945:
Arrives at Port Swettenham.

13 January 1945:
Departs Port Swettenham.

15 January 1945:
Arrives at Bengkalis and departs the same day.

16 January 1945:
Arrives At Singapore and remains there the rest of the month.

5 February 1945:
Departs Singapore.

8 February 1945:
Arrives at Singapore and remains there for the rest of the month.

5 March 1945:
W-4 departs Singapore for Moji with CH-9, CH-33, ASW detection vessel TATEISHI (fitted with special cable to detect submerged subs), auxiliary subchaser ex netlayer KAINAN MARU and auxiliary subchaser NITTO MARU No. 17 escorting convoy HI-88-I consisting of KOGA, YAMAKUNI and HOSEN MARUs, NANSHIN MARU No. 21, FUSHIMI MARU No. 2, TAKASAGO MARU No. 6 and HENZAN (MOTOYAMA) MARU No. 1.

15 March 1945:
Arrives at Cape St. Jacques, Indochina. The convoy is reorganized. KOGA MARU is detached. W-4 probably is detached and returns to Singapore.

11 June 1945:
On that day, FRUMEL decrypts the following message from Western Force, timed 112111: "KAMIKAZE and Minesweeper No. 4, under the orders of Commanding Officer KAMIKAZE, is to carry out escort of CHI 3rd Phase Convoy... TOOHOO MARU (in convoy) is to carry 4240 kilolitres of _ gasoline."

12 June 1945:
W-4 and destroyer KAMIKAZE depart Singapore escorting oiler TOHO MARU towards Indochina.

15 June 1945:
Off Samui Island, Gulf of Siam (Thailand). 10th Air Force Consolidated B-24 “Liberator” heavy bombers attack the convoy and sink TOHO MARU and damage W-4 and KAMIKAZE at 09-25N, 99-54E. Later, KAMIKAZE rescues 200 of TOHO MARU's survivors. Three crewmen are KIA.

16 June 1945:
On that day, FRUMEL decrypts the following message from KAMIKAZE, timed 151859: "From 1540 till 1800 we engaged a total of 8 B24’s. TOOHOO MARU was enveloped in flames and abandoned... Diving operations are in progress on port propellor of Minesweeper No. 4." (according to the attached comment, KAMIKAZE was escorting a convoy from Singapore to convoy). Later that day KAMIKAZE reports that she is proceeding to Patani anchorage for repairs to W-4.

E18 June 1945:
Arrives at Singapore.

10 July 1945:
On that day, FRUMEL decrypts the following message from 10th Base Force at Singapore: "Enemy submarine appeared 270 degrees 20 kilometers from Cape Rachad at 1110. Minesweeper No. 4, Minesweeper Division 44 and Special Minesweeper No. 9, under the orders of Minesweeper No. 4 are to sweep between Batu Pahat (1-47N 102-53E) and One Fathom Bank and destroy the submarine. At 0900 on 11th, Minesweeper No. 4 with suitable vessels is to provide protection for No. 1 KUROSHIO's minelaying south of Klang Channel, and return to Singapore on 12th unless otherwise ordered."

29 July 1945:
Off Batu Pahat, Port Klang. At 1400, a IJNAF patrol aircraft detects a moving oil slick 7 miles SW of Batu Pahat. Its crew identifies the target as a submarine and drops several depth charges. The same target is observed and attacked by another aircraft at 2000. A considerable quantity of oil is sighted in that location thereafter. W-4 receives the order to proceed to that area.

30 July 1945:
On that day, FRUMEL decrypts the following message from W-4, timed 301800: "Arrived at scene at 1745. With the help of a reconnaissance seaplane we have located and are attacking what appears to be a submarine with depth charges. (Position 184 degrees 10 miles from Batu Pahat.)"

15 August 1945:
Singapore. W-4's crew receives notice of the termination of hostilities with the Allied Powers.

11 July 1946:
Off Singapore. Scuttled by the Royal Navy.

10 August 1946:
Removed from the Navy List.

Thanks to Mr. Gilbert Casse of France, Mr. Matthew Jones of USA and Mr Sander Kingsepp of Estonia. Special thanks go to Hans Mcilveen of the Netherlands for info on FRUMEL intercepts.

-Bob Hackett and Peter Cundall.

Back to Minesweeper Page