KUSENTEI!



(Subchaser No. 46 by Takeshi Yuki scanned from "Color Paintings of Japanese Warships")

IJN Subchaser CH-1:
Tabular Record of Movement

© 2005-2017 Bob Hackett, Sander Kingsepp and Peter Cundall

Revision 9


19 June 1933:
Tokyo. Laid down at the Uraga dockyard.

23 December 1933:
Launched and numbered CH-1.

28 December 1938:
Completed and registered in the IJN.

7 December 1941: Operation "M" - The Invasion of the Northern Philippines:
CH-1 is in Rear Admiral (later Vice Admiral) Kubo Kyuji’s (38) (former CO of KAGA) 1st Base Force of Vice Admiral Takahashi Ibo’s (35)(former CO of YAMASHIRO) Third Fleet. CH-1 is attached to Takahashi's Philippines Seizure Force in LtCdr Okawara’s SubChasDiv 1 with CH-2 and CH-3. At 1630, departs Mako, Pescadores.

10 December 1941:
Beginning at 0550, participates in the landings at Aparri, Philippines. Led by Rear Admiral Hara Kenzaburo (37) in Light Cruiser NATORI with destroyers ASAKAZE, HARUKAZE, HATAKAZE, MATSUKAZE (Desdiv 5), FUMITSUKI, MINATSUKI, NAGATSUKI and SATSUKI (DesDIv 22), minesweepers W-15, W-16 and W-19 (MineSweepDiv 11), auxiliary gunboats MANYO, TOMITSU and TAIKO MARUs (GunboatDiv 2) and subchasers CH-13, CH-14 and CH-15 (SubChaseDiv 2). CH-1 is in SubChaseDiv 1 consisting of CH-1, CH-2 and CH-3. The aircraft transport KEIYO MARU and five transporrts make up the landing force.

12 December 1941:
At 1800 CH-1, CH-2, CH-3 and CH-13, CH-14 and CH-15 all depart Aparri for Takao.

14 December 1941:
At 1330 arrives at Takao.

18 December 1941:
At 1600 CH-1, CH-2, CH-3 and CH-13, CH-14 and CH-15 all depart Takao for Lamon Bay.

24 December 1941:
At 0330 CH-1, CH-2, CH-3 and CH-13, CH-14 and CH-15 all arrive Lamon Bay.

27 December 1941:
At 1000 CH-1, CH-2 and CH-3 depart Lamon Bay.

31 December 1941:
At 0800 arrives at Davao.

6 January 1942:
At 1920 CH-1 departs Davao.

7 January 1942:
At 0730 arrives at Magunaga Bay.

9 January 1942: Operation "H" - The Invasion of Celebes, Netherlands East Indies:
Light cruiser NAGARA, patrol boats PB-1, PB-2, PB-34, MineSweepDiv 21's W-7, W-8, W-9, W-11 and W-12 and SubChasDiv 1's CH-1, CH-2 and CH-3 depart Davao escorting eight transports carrying Captain (later Vice Admiral) Mori Kunizo's (40) (former CO of AO SATA) Sasebo No. 1 Combined Special Naval Landing Force (SNLF) and Rear Admiral Kubo's 1st Base Force.

11 January 1942: The Invasion of Menado, Celebes Dutch East Indies:
Rear Admiral Kubo’s 1st Base Force with NAGARA, MineSweepDiv 21, patrol boats and SubChasDiv 1’s CH-1, CH-2 and CH-3 provides escort for the Menado invasion force of eight transports carrying Sasebo No. 1 Combined SNLF.

At 0300, the SNLF lands on Kema, Celebes. At 0400, they land on Menado. Later, 334 men of Cdr (later Captain) Horiuchi Toyoaki's (50) (later XO of TAKAO) Yokosuka No. 1 SNLF (Air) are dropped successfully from Mitsubishi G3M1-L Nell converted transport aircraft in the Menado-Kema area. The paratroops seize Langoan airfield.

14 January 1942:
At 1400 CH-1 departs Menado.

20 January 1942:
At 1200 arrives at Davao.

24 January 1942:
At 2130 departs Davao.

27 January 1942:
At 0600 arrives Banka.

28 January 1942:
At 0200 departs Banka.

31 January 1942: The Invasion of Ambon Island, Netherlands East Indies:
The invasion convoy includes ten transports carrying 820 men of Rear Admiral (later Vice Admiral) Hatakeyama Kouichiro's (39) (former CO of KINUGASA) Kure No. 1 SNLF, elements of the Sasebo SNLF and the 228th Infantry Regiment.

The convoy's escort is provided by Rear Admiral (later Vice Admiral) Tanaka Raizo (41) in light cruiser JINTSU with DesDiv 8's DesDiv 15 and DesDiv 16, MineSweepDiv 21, SubChasDiv 1 CH-1, CH-2 and CH-3 and patrol boats P-34 and P-39. The convoy's air cover is provided by CarDiv 11's MIZUHO and the CHITOSE. CruDiv 5's NACHI and HAGURO, DesDiv 6's IKAZUCHI and DesDiv 7's USHIO and SAZANAMI provide the covering force.

5-10 February 1942: The Invasion of Makassar, Celebes:
Rear Admiral Kubo’s 1st Base Force with NAGARA, MineSweepDiv 21, SubchasDiv 2 and SubChasDiv 1’s CH-1, CH-2 and CH-3 provides escort for the Makassar invasion force of six transports carrying Mori's Sasebo Combined SNLF.

10 March 1942:
Assigned to Vice Admiral Takahashi's Southwest Area Fleet's newly formed Second Southern Expeditionary Fleet in Special Base Force 21's SubChasDiv 1 organized at Surabaya.

27 March 1942:
At 0530 tanker AKEBONO MARU departs Macassar escorted by submarine chaser CH-1.

2 April 1942:
At 0830 departs Bantam Bay. At 1430 arrives at Batavia.

3 April 1942:
At 0730 departs Batavia.

6 April 1942:
At 1445 arrives at Macassar.

8 April 1942:
At 1200 departs Macassar.

11 April 1942:
At 1825 arrives at Surabaya.

17 April 1942:
At 1100 departs Surabaya.

19 April 1942:
At 1830 arrives at Macassar.

22 April 1942:
At 0900 departs Macassar.

24 April 1942:
At 1530 arrives at Surabaya.

27 April 1942:
At 0845 departs Surabaya.

30 April 1942:
At 1130 arrives back at Surabaya.

1 May 1942:
SubChasDiv 1 is disbanded. CH-1 is reassigned to SubChasDiv 2 in the Yokosuka Naval District with CH-2 and CH-3.

11 May 1942:
CH-1 departs Surabaya escorting transport IKUSHIMA MARU.

14 May 1942:
At 0815, arrives at Terang Bay (NE Labuhanbadjo, Flores Island).

19 May 1942:
At 0630 departs Terang Bay. At 1400 arrives at Rinca Bay.

20 May 1942:
At 1830 departs Rinca Bay.

23 May 1942:
At 1300 arrives at Surabaya still with CH-1 as escort.

End May 1942-August 1942:
CH-1 escorts convoys. [1]

3 September 1942:
Departs Surabaya on an escort mission.

6 September 1942:
Arrives at Kendari.

7 September 1942:
Departs Kendari.

10 September 1942:
Arrives at Surabaya.

18 September 1942:
Departs Surabaya and anchors in the north part of the Western channel.

19 September 1942:
Late evening departs western channel.

21 September 1942:
Anchors off Kendari and departs late that evening.

24 September 1942:
In the late evening arrives at Surabaya.

28 September 1942:
Transfers to outside Surabaya Port.

2 October 1942:
Transfers back to Surabaya Port.

4 October 1942:
Departs Surabaya escorting a convoy to the Ambon area.

9 October 1942:
Arrives at Macassar.

19 October 1942:
Departs Macassar and escorts a convoy to Karimata Strait.

23 October 1942:
Arrives at Sourabaya.

1 November 1942:
Departs Surabaya on an escort mission to the Sunda Strait area.

7 November 1942:
Arrives at Batavia.

8 November 1942:
Departs Batavia.

10 November 1942:
Early am arrives at Surabaya.

16 November 1942:
Departed Surabaya and anchors in northern approaches.

17 November 1942:
Returns to Surabaya.

18 November 1942:
Departs Surabaya on escort mission to Padang.

21 November 1942:
Late evening arrives off Padang and commences patrol.

22 November 1942:
Arrives at Padang.

26 November 1942:
Departs Padang.

29 November 1942:
Arrives off northern approaches to Surabaya and awaits orders to enter port.

30 November 1942:
Arrives at Surabaya.

3 December 1942:
Departs Surabaya with minelayer AOTAKA escorting a four ship convoy No.2 Jichuhei.

18 December 1942:
Due to depart Surabaya with minelayer AOTAKA escorting a four ship convoy No.3 Jichuhei.

25 January 1943:
Departs Surabaya.

26 January 1943:
Arrives back at Surabaya.

30 January 1943:
Departs Surabaya on an escort mission.

4 February 1943:
Arrives at Ambon.

8 February 1943:
Departs Ambon still on escort mission.

14 February 1943:
Arrives off Surabaya and anchors in western channel, arriving in port late that evening.

19 February 1943:
Departs Surabaya escorting No.1 Ji-Yuso Convoy consisting of KUWAYAMA, KUNITAMA, SHINSUI and TAITO MARUs.

21 February 1943:
At 1505 USS THRESHER attacks the convoy at 07-54S 119-13E and torpedoes and badly damages KUWAYAMA MARU. TAITO MARU and one other vessel rescues survivors. The wreck is left difting and is discovered and sunk by USS THRESHER the following day. The minelayer AOTAKA is sent to assist the convoy.

24 February 1943:
Arrives at Ambon.

26 February 1943:
Early am departs Ambon on escort mission.

27 February 1943:
Arrives at Babo.

28 February 1943:
Departs Babo on escort mission.

2 March 1943:
Arrives at Kaimana.

3 March 1943:
Departs Kaimana still on escort mission.

6 March 1943:
Arrives back at Kaimana.

7 March 1943:
Early am departs Kaimana on escort mission.

13 March 1943:
Arrives at Surabaya.

20 March 1943:
Departs Surabaya on short patrol and arrives late that evening at the western channel where remains at anchor.

21 March 1943:
Departs western channel Surabaya escorting convoy No.6 Ji Yuso consisting of KUNITAMA, MAEBASHI and MEIGEN MARUs.

23 March 1943:
At 06-23S 112-43E MEIGEN MARU is torpedoed and sunk by USS GUDGEON. One passenger and seven of the crew are killed.

29 March 1943:
Arrives at Ambon.

31 March 1943:
Departs Ambon still escorting the same ships.

2 April 1943:
Arrives at Babo.

3 April 1943:
Departs Babo on an escort mission, probably escorting the same ships.

5 April 1943:
Arrives at Ambon.

7 April 1943:
Departs Ambon on an anti submarine sweep.

13 April 1943:
Arrives at Surabaya and departs shortly after on an anti submarine sweep of the Java Sea.

15 April 1943:
Arrives at Surabaya.

18 April 1943:
Departs Surabaya on an anti submarine sweep of the Java Sea.

21 April 1943:
Arrives at Surabaya.

22 April 1943:
Departs Surabaya on an escort mission.

28 April 1943:
Arrives at Ambon.

30 April 1943:
Departs Ambon.

6 July 1943:
Departs Surabaya on an escort mission.

10 July 1943:
Arrives at Maumere and patrols off Maumere.

14 July 1943:
Departs Maumere on an escort mission.

20 July 1943:
Arrives at Kupang and patrols off the port.

22 July 1943:
Departs Kupang on an escort mission.

24 July 1943:
Arrives at Waingapu and patrols off the port.

26 July 1943:
Departs Waingapu on an escort mission.

29 July 1943:
Arrives at Surabaya.

4 August 1943:
At 1815 departs Surabaya on an anti submarine sweep.

7 August 1943:
At 1310 arrives back at Surabaya.

12 August 1943:
At 1200 departs Surabaya escorting YAMAYURI MARU and possibly others.

15 August 1943:
At 1930 arrives at Balikpapan.

16 August 1943:
At 1200 departs Balikpapan on an escort mission.

19 August 1943:
At 1610 arrives at Surabaya.

20 August 1943:
At 0930 departs Surabaya on an escort mission.

25 August 1943:
At 1420 arrives back at Surabaya.

30 August 1943:
At 1100 departs Surabaya on an escort mission.

4 September 1943:
At 1730 arrives at Balikpapan.

10 September 1943:
At 1115 arrives at Tarakan.

12 September 1943:
At 1600 arrives at Balikpapan.

14 September 1943:
At 1130 arrives at Macassar. At 1230 departs port on an escort mission.

17 September 1943:
At 0900 arrives at Ambon.

19 September 1943:
At 1700 departs Ambon on an escort mission.

22 September 1943:
At 1140 arrives at Surabaya.

27 September 1943:
At 0700 departs Surabaya on an escort mission.

28 September 1943:
At 1915 arrives at Balikpapan.

1 October 1943:
At 1300 departs Balikpapan on an escort mission.

4 October 1943:
At 0900 arrives Banka Strait. At 1725 departs on an escort mission.

7 October 1943:
At 1345 arrives at Balikpapan.

9 October 1943:
At 0700 departs Balikpapan on an escort mission.

11 October 1943:
At 1600 arrives Jakarta.

13 October 1943:
At 0800 departs Jakarta on an escort mission.

17 October 1943:
At 1340 arrives at Balikpapan.

21 October 1943:
At 1030 departs Balikpapan on an escort mission.

24 October 1943:
At 0925 arrives at Surabaya.

31 October 1943:
At 1000 departs Surabaya on an escort mission.

3 November 1943:
At 1436 arrives at Surabaya.

22 December 1943:
At 1400 departs Surabaya on an escort mission.

26 December 1943:
Arrives at Waingapu.

29 December 1943:
Early am departs Waingapu.

1 January 1944:
Arrives back at Surabaya.

10 January 1944:
At 1400 departs Surabaya on an escort mission.

17 January 1944:
At 2015 arrives back at Surabaya.

1 February 1944:
Departs Surabaya and patrols area.

2 February 1944:
Arrives back at Surabaya.

5 February 1944:
At 0800 departs Surabaya on an escort mission.

6 February 1944:
CH-1 escorts HOKUROKU MARU (265 GRT) in Balikpapan area.

12 February 1944:
At 1100 arrives back at Surabaya.

17 February 1944:
At 1200 departs Surabaya on an escort mission.

22 February 1944:
At 1125 arrives back at Surabaya.

25 February 1944:
LtCdr Willard R. Laughon's (USNA ’33) USS RASHER (SS-269) intercepts a convoy consisting of RYUSEI and TANGO MARUs that is proceeding from Surabaya to Ambon escorted by minesweepers W-8 and W-11 and auxiliary subchaser TAKUNAN MARU No. 3. RYUSEI MARU is carrying about 6600 men: 4 detachments of various IJA units troops a total of 1244 Japanese nationals as well as 2865 Indian soldiers and 2559 coolies as passengers. At 2045, Laughon torpedoes and sinks TANGO MARU about 25 miles N of Bali Island at 07-41N, 115-10E. TANGO MARU is carrying 5700 troops, coolies and POWs (the latter probably predominantly Dutch Colonial (native) troops) and at least 3000 of these die. At 2225, Laughon sets up and fires four torpedoes at RYUSEI MARU. He gets three hits and she goes down at 07-55S, 115-15E. Again the death toll is horrendous with the ship taking down 4968 troops and coolies and 31 crewmen with her.[2]

At 0824, USN codebreakers intercept and decrypt a message that reads: "Subchaser No. 1 will proceed immediately to the position of the sinking of the RYUSEI MARU to rescue personnel.”

At 1330 CH-1 departs Surabaya.

6 March 1944:
At 1500 arrives back at Surabaya.

12 March 1944:
At 1200 departs Surabaya on an anti submarine sweep.

22 March 1944:
At 1635 arrives back at Surabaya.

25 March 1944:
At 1400 departs Surabaya on an escort mission.

7 April 1944:
At 0515 arrives back at Surabaya.

21 April 1944:
At 1850 departs Surabaya on patrol.

22 April 1944:
At 0900 returns to Surabaya.

23 April 1944:
At 1800 departs Surabaya on patrol.

24 April 1944:
At 0815 arrives back at Surabaya.

26 April 1944:
At 1500 departs Surabaya on an eacort mission.

29 April 1944:
At 1330 arrives back at Surabaya.

30 April 1944:
At 0700 departs Surabaya on an escort mission. Undertakes escort missions and anti submarine sweeps during the following month.

31 May 1944:
At 1815 arrives back at Surabaya. Remains at Surabaya for all of June.

7 July 1944:
At 0601 departs Surabaya with CH-2 and undertakes escort missions and anti submarine sweeps.

24 July 1944:
At 1330 arrives back at Surabaya.

8 August 1944:
At 1200 departs Surabaya and undertakes escort missions and anti submarine sweeps for the rest of the month.

14 September 1944:
At 1930 arrives back at Surabaya and remains there for the rest of the month.

4 October 1944:
At 1430 departs Surabaya on an escort mission.

10 October 1944:
At 1830 arrives back at Surabaya.

13 October 1944:
At 1500 departs Suurabaya on an anti submarine sweep.

16 October 1944:
At 1320 arrives back at Surabaya.

19 October 1944:
CH-3, CH-19, CH-63, auxiliary minesweepers CHOUN MARU No. 6 and CHOUN MARU No. 7 depart Miri escorting convoy MISHI-11 consisting of HIDA, KAZAN, ARAOSAN, HACHIJIN, NICHINAN MARUs and eleven unidentified merchant ships. That same day at 1600 CH-1 departs Surabaya.

E 21 October 1944:
CH-1 joins the convoy.

23 October 1944:
Arrives at Singapore.

1 November 1944:
At 0800 CH-1, CH-19, CH-26 and CH-36 depart Singapore for Manila escorting convoy SHIMA-04 consisting of HACHIJIN, AYAGIRI, ATSUTA and TOYO (YUTAKA) MARUs.

2 November 1944:
225 miles E of Singapore. At 1717, Lt (later Vice Admiral Sir) Hugh "Rufus" MacKenzie's British submarine HMS TANTALUS attacks the convoy. In heavy weather, MacKenzie torpedoes and sinks cargo ship HACHIJIN MARU, loaded with 3000 tons of aviation gasoline, cars, petroleum and foodstuffs, and damages CH-1 at 00-45N, 107-441E. Six crewmen on HACHIJIN MARU are killed.

11 November 1944:
Arrives at Bacuit Bay.

12 November 1944:
At 1215 arrives at Malampaya Bay.

13 November 1944:
At 0630 departs Malampaya Bay and at 1930 arrives at Coron Island.

14 November 1944:
At 0300 the convoy departs Coron Island. Rear Admiral (later Vice Admiral) Frederick C. Sherman (USNA ’10), in temporary command of Task Force 38, launches air strikes against shipping in the Philippines. Off Sablayan Island, Mindoro, convoy SHIMA-04 is attacked by F6F “Hellcat” fighter-bombers from USS YORKTOWN (CV-10). The Hellcats sink merchant oiler AYAGIRI MARU at 12-40N, 120-41E with the loss of 57 passengers and 4 of the crew were killed and her cargo of 4879 tons aviation gasoline, and damage IJA cargo ship TOYO MARU and CH-1, CH-19, CH-26 and CH-36. CH-1 is beached but later refloated.

22 November 1944:
At 0715 arrives alone at Manila.

29 November 1944:
CH-1 and minesweeper W-20 depart Manila escorting convoy MASHI-12A consisting of two unidentified merchant ships.

E 4 December 1944:
Arrives at Singapore. Thereafter, CH-1 undergoes repairs.

13 December 1944:
At 1900 YURIJIMA and submarine chaser CH-1 depart St Jacques escorting TOTTORI and KITAKAMI MARUs, tanker GYOSHIN MARU and Naval Landing Ship T-149 for Singapore.

16 December 1944:
At 0600 an enemy submarine is detected ahead of the convoy. The ships are ordered back to French Indo China except T-149 which detaches and apparently proceeds to Singapore independently while CH-1 and YURIJIMA conduct a hunt for the submarine.

4 April 1945:
At 1020 CH-1, followed 10 minutes later by CH-2 depart Surabaya on an anti submarine sweep.

11 April 1945:
At 1630 CH-1 arrives back at Surabaya.

15 April 1945:
At 1630 CH-1 departs Surabaya on an escort mission.

26 May 1945:
At 1258, USN codebreakers intercept and decrypt a message that reads: “-- CH-1 will depart immediately for vicinity of Mandalike Island to capture or sink the enemy submarine which attacked special [auxiliary] minesweeper Wa-105 and KAMISHIMA MARU there around 1400 May 25th --.”

28 May 1945:
Off Japara, Dutch East Indies. At 2135, CH-1 is damaged in a gun action by LtCdr Merrill K. Clementson's (USNA ’33) USS BLUEBACK (SS-326) and LtCdr Lucien B. McDonald's (USNA ’38) USS LAMPREY (SS-372) at 06-28S, 110-37E.

At 1258, USN codebreakers intercept and decrypt a message from CH-1 that reads: “At 2135 on the 28th submarine certain in position 06-28S, 110-37E.”

29 May 1945:
At 0755, codebreakers decrypt a message from CH-1 that reads: “In the engagement with two enemy submarines off Japara on May 28th lasting about 30 minutes after 2115, the following facts were considered of tactical value --(description of allied methods of attack)--.”

16 July 1945:
W of Surabaya, Java. At 0430, CH-1 is escorting gunboat NANKAI (ex-Dutch minelayer REGULUS) when they are attacked by LtCdr (later Cdr) William H. Hazzard's (USNA ’35) USS BLENNY (SS-324). Hazzard fires a total of 12 torpedoes in a night surface radar attack and claims four hits that sink NANKAI at 05-26S, 110-33E.

At about 0700, Hazzard finds and shells CH-1 with his 5-inch deck gun. BLENNY gets two hits that set CH-1 on fire at 05-16S, 110-17E.

19 July 1945:
At 1545, USN codebreakers intercept and decrypt a message that reads: “NANKAI was enroute Singapore from Surabaya via Batavia engaged in transportation operation under escort of CH-1 when she was attacked by an enemy submarine which fired two torpedoes. She probably sank --- 0430 on July 16th in position 05-16S, 110-17E. The vicinity was swept by CH-1 and a float reconnaissance plane. On the 17th the float reconnaissance plane ------ floating in position 05-07S, 110-19E. Further search was carried out by CH-5 and SHONAN MARU No. 17 but neither survivors nor flotsam were seen. Secret documents apparently sank with the hull.”

11 July 1946:
Singapore. CH-1 is scuttled by the Royal Navy.

10 August 1946:
Removed from the Navy List.


Author's Notes:
[1] Litle data were found detailing CH-1's movements during the timeframe of May 1942-October 1944. Readers with access to such data are requested to post the information on the Discussion and Questions board or at j-aircraft.org's IJN Ship Message Board

[2]The massive death toll from these combined sinkings and the deaths of so many non combatants (the Javanese coolies) has passed almost without comment over the years in contrast to much smaller sinkings that involve the deaths of substantial numbers of westerners (whether POW's or Civilian Non Combatants). As it happens an allegedly large but unspecified number of western POWs were lost on TANGO MARU although Romusha (coolie) casualties were much higher

Thanks for assistance go to Cdr John D. Alden, USN-Ret and to Mr. Gilbert Casse of France. Thanks also go to John Whitman of the USA for info on CNO intercepts of Japanese messages.

-Bob Hackett, Sander Kingsepp and Peter Cundall.


Back to Subchaser Page