W-21 (W-19 class) scanned from Gakken, V. 45
IJN Minesweeper W-21:
Tabular Record of Movement
© 2009-2018 Bob Hackett and Peter Cundall
20 September 1940:
Harima. Laid down at Harima Shipbuilding.
28 February 1941:
Launched and numbered W-21.
26 June 1942:
Reserve Lt Moriyasu Sakae is appointed Chief Equipping Officer.
30 June 1942:
Completed and registered in the IJN. Attached to Maizuru Naval District. Reserve Lt Moriyasu Sakae is the Commanding Officer.
19 July 1942:
70 degrees 10 nautical miles off Muko Jima, Bonins. W-21 joins as escort to auxiliary gunboat NIKKAI MARU towing water barge KOSHO No. 4008 from Yokosuka to Rabaul.
21 July 1942:
W-21 is detached to Saipan.
25 July 1942:
W-21 rejoins as escort.
26 July 1942:
At 0800 arrives at Truk.
31 July 1942:
At 1500 departs Truk still escorting NIKKAI MARU towing KOSHO No. 4008. Auxiliary minesweeper SEKI MARU No. 3 joins as an additional escort.
5 August 1942:
At 1530 arrives at Rabaul.
6 August 1942:
Rabaul. Refueled by KAGU MARU.
7 August 1942:
At 1650 departs Rabaul on an escort mission.
10 August 1942:
At 1730 arrives back at Rabaul.
12 August 1942:
At 2030 departs Rabaul on an escort mission.
13 August 1942:
At 0710 arrives back at Rabaul. Refueled by KAGU MARU.
15 August 1942:
At 1530 departs Rabaul for Shortland.
20 August 1942:
At 0630 departs Shortland and participates in the seizure at Gizo, New Georgia.
23 August 1942:
At 1215 arrives at Gizo.
2 October 1942:
At 0500 departs Rabaul on an escort mission.
7 October 1942:
At 1630 arrives back at Rabaul.
9 October 1942:
At 0530 departs Rabaul on an escort mission.
11 October 1942:
St George's Channel, near Rabaul New Britain. An RAAF No. 6 Squadron Lockheed "Hudson" light bomber, based at Port Moresby, attacks KIYOKAWA MARU being escorted by minesweeper W-21 at 05-40S, 152-53E. The crew claims two direct hits from 900 feet with 250-lb bombs and a near miss. The ship swings hard through 180 degrees and loses way. Dense smoke rises from her decks. The Hudson's crew reports she was carrying a deck cargo of "at least 12 Zeros".
16 October 1942:
At 1700 arrives back at Rabaul.
20 October 1942:
At 1800 W-20 and W-21 depart Rabaul on an escort mission to Shortland.
26 October 1942:
At 1930 arrives back at Rabaul.
30 October 1942:
At 1700 departs Rabaul on an escort mission.
7 November 1942:
At 1600 arrives back at Rabaul.
14 November 1942:
At 0600 departs Rabaul on an escort mission.
17 November 1942:
At 1100 arrives back at Rabaul.
20 November 1942:
At 1620 departs Rabaul on an escort mission to Shortland likely escorting storeship TAKUNAN MARU.
25 November 1942:
At 0200 arrives back at Rabaul likely escorting SHINYUBARI MARU from Buin.
26 November 1942:
At 1150 departs Rabaul on an escort mission possibly escorting aircraft transport FUJIKAWA MARU.
28 November 1942:
At 2130 arrives back at Rabaul escorting HEIYO MARU.
30 November 1942:
At 1640 departs Rabaul on an escort mission.
4 December 1942:
At 0915 arrives back at Rabaul.
7 December 1942:
At 1225 departs Rabaul on an escort mission, possibly with submarine chaser CH-16.
12 December 1942:
At 1145 arrives back at Rabaul.
14 December 1942:
At 0900 departs Rabaul on an escort mission.
20 December 1942:
At 0810 arrives back at Rabaul.
21 December 1942:
At 1700 departs Rabaul on an escort mission.
25 December 1942:
At 0530 arrives back at Rabaul.
26 December 1942:
At 1015 departs Rabaul on an escort mission.
27 December 1942:
At 1430 arrives back at Rabaul.
28 December 1942:
At 0800 departs Rabaul on an escort mission.
31 December 1942:
At 0945 arrives back at Rabaul.
6 January 1943:
At 1500 departs Rabaul on an escort mission.
10 January 1943:
At 2100 arrives back at Rabaul.
16 January 1943:
At 0440 departs Rabaul on an escort mission.
19 January 1943:
At 0800 arrives back at Rabaul.
22 January 1943:
At 1730 departs Rabaul on an escort mission.
26 January 1943:
At 1400 arrives back at Rabaul.
27 January 1943:
At 1130 departs Rabaul on an escort mission.
30 January 1943:
At 1000 arrives back at Rabaul.
31 January 1943:
Departs Rabaul on escort mission.
1 February 1943:
At 0805 arrives back at Rabaul.
3 February 1943:
At 0730 departed to a disaster scene returning at 2115.
8 February 1943:
At 1700 departs Rabaul on an escort mission.
12 February 1943:
At 0520 returns to Rabaul.
14 February 1943:
At 1430 departs Rabaul on an escort mission.
19 February 1943:
W-21 and minelayer TSUGARU are escorting transport HIBARI MARU. At 1735 at 06-27S 156-05E off the coast of Bougainville Island, HIBARI MARU is hit in the stern by a single torpedo from USS GATO. TSUGARU and the W-21 immediately counterattack unsuccessfully.
21 February 1943:
At 1510 returns to Rabaul.
24 February 1943:
At 1700 departs Rabaul on an escort mission.
27 February 1943:
At 0847 returns to Rabaul.
28 February 1943:
At 2235 departs Rabaul on an escort mission.
1 March 1943:
Meets up with WAKAMATSU MARU No. 1.
2 March 1943:
At 0600 returns to Rabaul.
3 March 1943:
At 2200 departs Rabaul on an escort mission.
5 March 1943:
At 1130 arrives back at Rabaul.
6 March 1943:
At 0945 departs Rabaul on an escort mission.
9 March 1943:
At 0500 arrives back at Rabaul.
12 March 1943:
At 1500 departs Rabaul on an escort mission.
15 March 1943:
At 0530 arrives back at Rabaul.
17 March 1943:
At 1400 departs Rabaul on an escort mission.
20 March 1943:
At 0830 arrives back at Rabaul.
23 March 1943:
At 1400 departs Rabaul on an escort mission.
28 March 1943:
At 0730 arrives back at Rabaul.
29 March 1943:
At 1345 departs Rabaul on an escort mission.
31 March 1943:
Departs Shortland escorting NISSEN MARU No.3 and WAKAMATSU MARU No. 1.
2 April 1943:
At 0515 arrives at Rabaul.
3 April 1943:
At 1200 departs Rabaul on an escort mission.
9 April 1943:
At 0630 arrives at Rabaul.
10 April 1943:
At 0845 departs Rabaul on an escort mission.
13 April 1943:
At 1200 arrives at Rabaul.
18 April 1943:
At 1450 departs Rabaul on way to Takao after transfer to Takao Guard Unit, Taiwan.
9 May 1943:
W-21 departs Takao for Manila escorting convoy No. 748 consisting of SEIAN MARU and transports EIKO MARU No. 2 GO and HOKUHI (ex Philippine CETUS), ISUZU and KOSHIN MARUs and one unidentified merchant ship.
13 May 1943:
Arrives at Manila.
21 June 1943:
Met up with OYO MARU escorted by auxiliary patrol boat YOBAI MARU at 24-21N 120-18E.
1 December 1943:
At sea escorting convoy (with W-17 apparently to meet convoy) consisting of minesweeper W-22, auxiliary gunboat CHOAN MARU No.2 GO and merchant ship TATSUTAGAWA MARU. The latter is the sole merchant survivor of convoy 3123 that had originally consisted of five merchant ships escorted by the destroyer OITE.
On that day, FRUMEL intercepts the following message from W-17, dated 010730:
"Will meet convoy in 12-40N, 141-10E."
6 December 1943:
At 1652 arrives at Truk.
10 December 1943:
Truk. At 1230, W-21 departs Truk for Rabaul with minesweeper W-22 and auxiliary submarine-chaser CHa-48 escorting convoy No. 1103 consisting of NIKKO and KIMISHIMA MARUs and SHINSEI MARU No. 18. NIKKO MARU is towing an unidentified midget submarine and KIMISHIMA MARU is towing a midget supply submarine.
15 December 1943:
At 0810, SHINSEI MARU No. 18 that suffered navigational troubles a few days earlier leaves the convoy with W-22 and CHa-48 and heads for Kavieng, New Ireland. At 1210, the same day, the rest of the convoy is attacked by American aircraft, but incurs no damage.
16 December 1943:
At 1336, the remainder of convoy No. 1103, including the midget submarine and the tokugata unkato midget supply submarine, arrive at Rabaul.
18 December 1943:
At 0155 departs Rabaul. At 1431 arrives at Kavieng.
25 December 1943:
Kavieng. Aircraft from Rear Admiral (later Admiral) Frederick C. Sherman’s (USNA ‘10)(former CO of USS LEXINGTON, CV-2) TG 50.2's USS BUNKER HILL (CV-17) and USS MONTEREY (CVL-26) attack and sink transport TENRYU MARU (five crewmen KIA) and damage W-21, minesweeper W-22 and KIYOSUMI MARU. W-21 is badly damaged and spends almost the whole of January under repair at Kavieng.
26 December 1943:
Salvage tug NAGAURA transfers a pump on board.
28 December 1943:
At 0945, USN codebreakers intercept and decrypt a message from the CO of W-21 that reads: “Nine enlisted men reported as killed in action at 0605, 25 December in ----- area.” 
31 January 1944:
Departs Kavieng to meet up with convoy 3123 (or 2312) consisting of MATSUTAN, NIPPONKAI, MARUs escorted by destroyers MATSUKAZE and FUMITSUKI.
1 February 1944:
At 0600, W-21 joins the convoy.
2 February 1944:
At 1045, an air attack develops. FUMITSUKI and W-21 are both damaged.
4 February 1944:
At 1600, W-21 because of damage from earlier attacks is forced to detach but later makes running repairs and rejoins convoy.
6 February 1944:
At 1715, arrives at Truk and spends remainder of February undergoing repairs there.
7 February 1944:
The wounded are transferred to hospital ship TENNO MARU (ex-Dutch OP TEN NOORT).
6 March 1944:
At 1130, W-21 departs Truk escorting convoy No. 4304 consisting of URAKAMI, SHIRANE, JUZAN and AWAJI MARUs also escorted by kaibokan AMAKUSA and MIKURA and subchaser CH-33.
E 7 March 1944:
Submarine Chasers CH-14 and CH-51 that had left Chichi Jima at 1007 on 3rd March join as additional escorts.
10 March 1944:
At 1222, arrives at Saipan.
14 March 1944:
At 1540, W-21 departs Saipan with subchasers CH-18 and CH-17 escorting convoy No. 4313-B consisting of JUZAN and SHIRANE MARUs and SEIKAI MARU No. 1. JUZAN MARU is towing damaged SANTO MARU.
17 March 1944:
At 1200, CH-18 and CH-17 are detached.
20 March 1944:
At 0700, the convoy arrives safely at Chichi-Jima.
21 March 1944:
At 1700, departs Chichijima and carries out further running repairs while steaming north-west.
24 March 1944:
At 0925, arrives at Saiki and departs there at 1835.
26 March 1944:
At 1145, arrives at Maizuru.
30 March 1944:
At 0900, departs Maizuru to Takamatsu Dockyard for permanent repairs.
1 April 1944:
At 1325, arrives at Takamatsu. Spends the whole of April-June in the dockyard.
Reserve Lt Ujihara Shigeru assumes command.
13 July 1944:
At 0700, departs Takamatsu. At 1630, arrives at Kure.
15 July 1944:
At 0900, departs Kure.
16 July 1944:
At 0840, arrives at Sasebo.
29 July 1944:
At 1730, departs Sasebo.
30 July 1944:
At 0730, arrives at Moji.
31 July 1944:
At 1557, departs Moji and, at 1658, arrives at Mutsure Jima.
1 August 1944:
At 0445, departs Mutsure Jima on patrol and escorting a southbound convoy.
6 August 1944:
At 0605, arrives at Kinmu Bay. At 1743, arrives at Naha.
8 August 1944:
At 0730, W-21 departs Naha escorting a convoy consisting of KAZUURA, TSUSHIMA, GYOKU MARUs. At 1240, W-21 launches a depth charge attack on a suspected enemy submarine, but without result.
11 August 1944:
At 1835, arrives at Shanghai.
13 August 1944:
At 1612, departs Shanghai.
15 August 1944:
At 1420, arrives at Moji.
18 August 1944:
At 1735, departs Moji and arrives at Mutsure Jima at 1845.
19 August 1944:
At 0600, W-21 departs Moji with minelayer SHIRATAKA, destroyers WAKABA, HIBIKI (and probably HATSUHARU) escorting convoy MI-15 consisting of URATO, RIKKO, CHIYODA, EKKAI, TAISHO, HOKUSEN, TSINGTAO, TOSHIGAWA and NANSEI MARUs and OKINOYAMA MARU No. 5.
24 August 1944:
At 0948 arrives at Kirun (Keelung), Formosa (Taiwan) and departs at 1552.
25 August 1944:
Arrives at Takao at 1600.
26 August 1944:
At 1300, W-21 departs Takao alone to investigate a contact, but returns at 1358.
30 August 1944:
At 1500, W-21 departs Takao for Manila with minelayer SHIRATAKA, kaibokan CD-10 and CD-20 escorting reorganized convoy MI-15 that now consists of RIKKO, TAISHO, OKUNI (TAIKOKU), EIKYU, SHINYO, NANSEI, HOSEN and CHIYODA MARUs with UNKAI MARU No. 5, OKINOYAMA MARU No. 5 and KYOEI MARU No. 10.
31 August 1944:
Luzon Strait, S of Formosa. At about 0220, LtCdr (later Rear Admiral) Charles E. Loughlin's (USNA ‘33) USS QUEENFISH (SS-393) hits CHIYODA MARU with four torpedoes and sets her afire. At 0240, CHIYODA MARU sinks. She was carrying 430 passengers, coal briquettes and drummed gasoline. 382 passengers and 15 of the crew are KIA. Loughlin also damages oiler RIKKO MARU steaming in ballast.
LtCdr (later Vice Admiral) Eli T. Reich's (USNA ‘35) USS SEALION (SS-315), a member of "Ben's Busters" with USS GROWLER (SS-215) and USS PAMPANITO, enters the Bashi Strait. USS SEALION’s SJ radar picks up the convoy. Reich makes a night surface approach. He sets up and fires six torpedoes, but they all run erratically. About 0500, Reich swings USS SEALION and fires four stern torpedoes at a large tanker. He claims two hits.
Alerted by code-breaker's "Ultra" signals, LtCdr (later Rear Admiral/MOH) Eugene B. Fluckey's (USNA ‘35) USS BARB (SS-220) intercepts the convoy. At about 0700, Fluckey torpedoes OKUNI MARU. She sinks stern first. Three crewmen are KIA. Fluckey also sinks the 45th Minesweeper Squadron's HINODE MARU No. 20 that was patrolling the area. Two crewmen are KIA.
USS SEALION evades the convoy's escorts. Still surfaced, LtCdr Reich makes an “end-around” approach and works his way ahead of the convoy. Reich misidentifies minelayer SHIRATAKA as a destroyer. He begins a submerged approach. At 0730, Reich hits SHIRATAKA with two of three torpedoes. At 1115, SHIRATAKA sinks at 20-55N, 121-07E. Captain Miki Takahide (46) is KIA. He is promoted Rear Admiral, posthumously.
1 September 1944:
Anchors off Fengliang and departs at 1555.
7 September 1944:
At 1000, the convoy arrives at Manila.
9 September 1944:
At 0716, coaled from UNKAI MARU No. 12 and, at 2012, departs Manila on patrol.
10 September 1944:
At 0525, departs Manila in convoy MAMO-03 with submarine chaser CH-19 consisting of IJA landing craft depot ship KIBITSU MARU, ex-armed merchant cruiser GOKOKU MARU and ex-seaplane tender KAGU MARU.
11 September 1944:
At 0918, meets up with HI-72 convoy consisting of ASAKA, NANKAI, KIMIKAWA, RAKUYO, ZUIHO, KIBITSU and KACHIDOKI MARU (ex-PRESIDENT HARRISON). RAKUYO MARU carries 1,317 POWs and KACHIDOKI MARU carries 900 POWs.
12 September 1944:
At 0200, Cdr Thomas B. Oakey’s (USNA ’34) USS GROWLER (SS-215), torpedoes HIRADO. She blows up and sinks at 17-54N, 114-49E. Cdr Segawa and 106 sailors are KIA. LtCdr Segawa posthumously promoted Cdr. Rear Admiral Kajioka, victor of Wake Island, is also KIA. He is promoted Vice Admiral, posthumously.
At 0531, LtCdr (later Vice Admiral) Eli Reich’s (USNA ’35) USS SEALION II (SS-315) torpedoes RAKUYO MARU but she stays afloat for another 13 hours, sinking at 1830 that evening. She is carrying 1,318 Allied POWs (601 British, 716 Australian and several US POWs), of whom 1,159 are lost. At about 0700, SHIKINAMI is torpedoed by GROWLER and sinks 240 miles S of Hong Kong at 18-16 N, 114-40 E. MIKURA rescues eight officers and 120 men. At 2254, KACHIDOKI MARU with 950 Allied POWs aboard is hit by LtCdr Paul E. Summers’ (USNA ’36) USS PAMPANITO (SS-383) at 19-25N, 112-23E. At 2337, she founders and 12 sailors and 476 passengers (including 431 POWs) are lost with her. USS PAMPANITO also sinks ZUIHO MARU with no survivors. The Japanese rescue a few POWs from the two prison ships. The survivors are transferred to KIBITSU MARU.
The Japanese rescue a few POWs who are transferred to KIBITSU MARU and taken to Japan. American submarines later return to the scene and rescue 159 survivors of whom seven die enroute to Saipan. In all, 92 Australian and 60 British ex-POWs survive.
At 0840, USN codebreakers intercept a message from unknown Japanese station that says, “Have rescued survivors of HIRADO (survivors include the staff and 26 men plus 74 crew members. Captain of HIRADO killed in action ---.”
At 2150, W-21 arrives at Marivales.
15 September 1944:
At 0835, departs Marivales. At 1105 arrives at Manila.
16 September 1944:
At 0800 departs Manila.
20 September 1944:
At 1312, arrives at Shanghai.
23 September 1944:
At 0945 departs Shanghai. At 1659 arrives at Ssu Chiao Shan.
24 September 1944:
At 1621, departs Ssu Chiao Shan.
27 September 1944:
At 0035, arrives at Foochow.
28 September 1944:
At 0210, departs Foochow in convoy consisting of cargo-passenger ship KIUKIANG (KYUKO) MARU escorted by Minesweeper W 21 and torpedo boat TOMOZURU.
29 September 1944:
At 0738, arrives at Kirun.
30 September 1944:
At 0800, depart Kirun escorting a convoy.
2 October 1944:
At 2135, arrives at Ssu Chiao Shan.
3 October 1944:
At 0700 departs Ssu Chiao Shan. At 1400 arrives at Shanghai.
6 October 1944:
At 0900 departs Shanghai. At 1610 arrives at Ssu Chiao Shan and departs at 2300 escorting a convoy that includes AKAGISAN MARU.
8 October 1944:
At 2107, arrives at Amoy.
9 October 1944:
At 1657, departs Amoy having detached from convoy.
13 October 1944:
At 1618, arrives at Ssu Chiao Shan.
14 October 1944:
At 0649, departs Ssu Chiao Shan escorting TOUN and AKAGISAN MARUs. At 1350 arrives at Shanghai.
17 October 1944:
At 1602, departs Shanghai.
18 October 1944:
At 1310, arrives at Ssu Chiao Shan.
19 October 1944:
At 0657, departs Ssu Chiao Shan. At 1300 arrives at Woosung and at 1606 arrives at Kiangnan, where docked.
26 October 1944:
At 1100, undocked and transferred to Shanghai. At 1730, fleet stores ship MAMIYA departs Mutsure in convoy HI-79 consisting of transports KAGU, MELBOURNE and ARIMASAN MARUs and tankers TENEI and MATSUSHIMA MARUs. The ships initially are escorted by light cruiser KASHII, kaibokan NOMI, UKURU and minelayer NIIZAKI.
27 October 1944:
Kaibokan CD-17 joins the escort.
28 October 1944:
W-21 joins the escort.
29 October 1944:
MELBOURNE MARU is detached for Keelung escorted by UKURU and CD-17.
30 October 1944:
HI-79 arrives at Takao. W-21, MAMIYA and KAGU MARU
2 November 1944:
Departs Takao in convoy TAMA-31A consisting of KAGU MARU and Landing Ships T-111, T-139, T-140, and T-160 escorted by Submarine Chaser CH-20 and Minesweeper W-21.
3 November 1944:
At 1840, arrives at Lapoc Bay. Departs at 2357.
4 November 1944:
At 1758, Cdr Wreford G. Chapple's (USNA ‘30) USS BREAM (SS-243) torpedoes and sinks KAGU MARU at 16-30N, 119-46E. 24 crewmen and 22 guards are KIA.
At 1826, USN codebreakers intercept and decrypt a message from W-21 that reads: “At 1745 [Transport No. 111] torpedoed---- sunk--- request replenishment 15-56N, 119-44E.” 
At 2025, codebreakers decrypt another message that reads: “Coast Defense Ships No. 18 and No. 26 will sortie at once from Manila and hasten to scene of disaster (15-56N, 119-44 E) where they will engage in salvage (towing).”
5 November 1944:
At 1806, arrives at Subic Bay.
7 November 1944:
At 0342, arrives at Manila. Probably embarks personnel from the No. 103 Repair Facility at Cavite.
8 November 1944:
At 0900, W-21 departs Manila.
9 November 1944:
At midnight, arrives at Santa Cruz.
10-17 November 1944:
Santa Cruz harbor. Cruiser KUMANO, hit by two torpedoes off Cape Bolinao on 6 November, undergoes emergency repairs by personnel brought up from the Manila Repair Facility. W-21 keeps ASW lookout over KUMANO.
17 November 1944:
At midnight, departs Santa Cruz.
18 November 1944:
TOYO MARU No. 3 supplies 50 tons of coal to W-21. At 1415, arrives at Manila.
20 November 1944:
At 1015, departs Manila to pick up RYUEI MARU survivors (had stranded 22 October S of Puerto Princesa)
27 November 1944:
At 0142, arrives Manila with survivors onboard. At 2045 departs Manila.
28 November 1944:
At 0805, arrives at Santa Cruz. Departs at 1946.
29 November 1944:
At 0715, W-21 arrives at Manila and departs at 0825 escorting MASA-12 convoy consisting of an unknown number of merchant ships.
4 December 1944:
At 1225, arrives at Saigon, Indochina.
12 December 1944:
At 1300, departs Saigon. At 1700, arrives at St Jacques, Indochina.
15 December 1944:
At 0742, departs St Jacques to meet convoy MASA-14. At 1745 arrives back at St Jacques.
16 December 1944:
At 1304, departs St Jacques. At 1648 arrives at Saigon.
18 December 1944:
At 0715, departs Saigon. At 1030 arrives at St Jacques.
19 December 1944:
At 0802 departs St Jacques in convoy SAMA-14 consisting of SHINNO, RYUSHO, SHINSEI, BINGO MARUs and at least two other unidentified merchant ships escorted by Minesweeper W 21 and kaibokan CD-1, CD-3, CD-130 and CD-134.
20 December 1944:
At 1644, arrives at Cap Padaran, Indochina. Departs from there at 2003.
21 December 1944:
At 1905, arrives at Nha Trang, Indochina.
23 December 1944:
At 0807, departs Nha Trang but SHINNO MARU broke down and at 0915 convoy returned to port. At 1814 departs Nha Trang again.
24 December 1944:
At 0516, arrives at Qui Sande Bay, Indochina. At 0910 departs. At 2050, the No.6 ship in the convoy runs aground.
25 December 1944:
At 0900, the No. 6 ship is towed off and the convoy resumes its voyage. At 2126 arrives at Qui Nhon, Indochina.
26 December 1944:
At 1006, departs Qui Nhon.
27 December 1944:
At 1558, arrives at Yulin and departs at 1901.
30 December 1944:
Between 1104 and 1124, the convoy is attacked by a B-24, but without sustaining any damage.
1 January 1945:
At 1437 arrives at Saei (Tsoying), Formosa. Because of pending air raids, the convoy is ordered out of port.
3 January 1945:
At 1135, anchors outside Takao but leaves at 1255.
8 January 1945:
W-21 is detached from SAMA-14 at 0800 and ordered to proceed to rescue survivors of SHINSEI MARU under air attack. At 1430, SHINSEI MARU sinks in shallow water with the loss of seven crewmen and at 1817, W-21 arrives and takes onboard survivors. Later that day the ship arrives back at Takao.
9-14 January 1945:
Because of airraids moves in and out of Takao port frequently.
14 January 1945:
At 1100 W-21 departs Takao with destroyer ASAGAO, kaibokan YASHIRO, CD-1, CD-134 and CD-56 escorting convoy TAMO-37 consisting of DAIKO, BRAZIL, DAII, DAIIKU and MELBOURNE MARUs and two unidentified merchant ships.
16 January 1945:
At 1800, DAIKO MARU suffers an engine breakdown and the convoy temporarily anchors on China Coast. CD-130 joins the convoy.
17 January 1945:
At 0500, BRAZIL MARU suffers an engine breakdown. At 0530, the ships again departed and at 1626 anchor. BRAZIL MARU is then taken in tow by DAII MARU.
At 1650, departs the anchorage and at 2040 temporaily anchors again.
18 January 1945:
At 0600, BRAZIL MARU towed by DAII MARU depart and at 0710 the rest of the convoy departs. At 1430, kaibokan CD-36 joins and takes over escort of BRAZIL and DAII MARUs.
19 January 1945:
At 1400, arrives at Ssu Chiao Shan.
20 January 1945:
At 0708, departs Ssu Chiao Shan.
23 January 1945:
At 1610, CD-130 drops depth charges. At 1750, CD- 134 drops depth charges. At 2015, arrives at Mutsure Jima and later arrives at Moji. At unknown date departs.
25 January 1945:
Arrives at Sasebo and enters drydock for repairs.
10 February 1945:
At 0936, undocked.
12 February 1945:
At 1010, departs Sasebo on trials and then returns.
14 February 1945:
W-21 departs Sasebo and at 1700 meets up at sea with kaibokan CD-150, CD-72, UKU and submarine chaser CH-60 escorting convoy MOTA-37 from Moji consisting of DAIKO and DAIIKU MARUs and three unidentified merchant ships.
18 February 1945:
At 1700 arrives at Ssu Chiao Shan. W-21 is detached.
19 February 1945:
At 0800 the convoy departs Ssu Chiao Shan. Meanwhile at 0900, W-21 arrives at Shanghai and remains there for next 10 days.
28 February 1945:
At 1110, W-21 departs Shanghai for Ssu Chiao Shan and joins convoy HIKARI-05 consisting of HYOGO MARU and TAMON MARU No. 12 escorted by subchaser CH-23 and auxiliary subchaser CHa-38.
2 March 1945:
At 1030, departs Ssu Chiao Shan.
4 March 1945:
At 1827, arrives at Swatow. Detaches from convoy.
5 March 1945:
At 1400, departs Swatow escorting convoy HIKARI-06 consisting of YUKIKAWA MARU and KORI GO.
8 March 1945:
At 2328 arrives at Ssu Chiao Shan.
11 March 1945:
At 0555, W-21 departs Ssu Chiao Shan escorting convoy HIKARI-06 convoy now consisting of YUKIKAWA, KITSURIN and SHINYO MARU's and KORI GO. At 1300, arrives at Shanghai.
15 March 1945:
At 1301, departs Shanghai to meet a convoy. At 1708, arrives at the entrance to the Yangtse River..
16 March 1945:
At 0352, W-21 departs from the entrance and joins the KITSURIN MARU Convoy consisting of KITSURIN MARU and possibly KIUKIANG (KYUKO) MARU.
19 March 1945:
At 1826, arrives Moji.
20 March 1945:
At 0600, departs Moji. At 1732 arrives at Sasebo.
26 March 1945:
At 0800, departs Sasebo escorting SHINTO MARU.
29 March 1945:
At 1818, arrives at Tinghai.
31 March 1945:
At 1200, departs Tinghai alone to picket boat EIKICHI MARU's disaster area.
2 April 1945:
At 0215, arrives Ssu Chiao Shan.
3 April 1945:
At 1805, departs Ssu Chiao Shan.
5 April 1945:
At 1905, arrives at Swatow.
7 April 1945:
At 0600, departs Swatow escorting convoy consisting of SHINTO, KIUKIANG (KYUKO), SHINTON and TAIKYU MARUs. At 1943 arrives at Shanghai.
10 April 1945:
East of the mouth of the Yangtze River, China. At 1350, departs Shanghai escorting an unknown ship. At 1600, W-21 is damaged by a mine laid by USAAF B-29s on 4 and 28 March.
11 April 1945:
At 1300, arrives at Kiangnan after being towed back to Shanghai. Under repairs for several weeks.
8 May 1945:
Departs Shanghai with destroyer TSUBAKI escorting convoy SHIMO-04 consisting of unidentified merchant ships. Scheduled to arrive at Mutsure on 16th May.
17 May 1945:
Detached from the convoy that proceeds to Yuya Wan.
30 June 1945:
Reserve Lt Ado Takuji is appointed Commanding Officer.
15 August 1945:
W-21’s crew learns of the end of hostilities.
25 October 1945:
Removed from the Navy List.
1 December 1945:
Assigned to the Allied Repatriation Service.
29 January 1946:
7 February 1946:
Arrives at Pusan. Emabarks 648 former Japanese servicemen for repatriation and departs that same day.
10 February 1946:
Arrives at Maizuru. Makes no further repatriation voyages.
1 October 1947:
At Tsingtao. Ceded to the United States as a war reparation.
7 October 1947:
Yellow Sea. Scuttled as artillery target at 35-19N, 123-31E.
 CNO analysts say “W-21 appears to have gone to Rabaul about the middle of January and thence to Truk. On 29 February 1944 she was ordered to return to the Empire for repairs which appear to have been completed about 15 April.”
 According to Kimata W-21 and the convoy was attacked on 1st February.
 T.111 was not sunk on 4 Nov '44, but only damaged by a torpedo probably fired by USS SAILFISH (SS-192). T.111 was finally sunk on 24 Nov'44 by aircraft.
Thanks go to the late John Whitman of Virginia, USA for info on CNO intercepts of Japanese messages, Mr Matthew Jones, of Mississippi, USA for CO information and to Mr. Gilbert Casse of France and Mr. Sander Kingsepp of Estonia for general assistance. 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.