KYUSETSUMOKAN!
HOKAKUMOTEI!
(SHUKO MARU, sistership of CHOKO MARU, prewar)
IJN CHOKO MARU:
Tabular Record of Movement
© 2021 Gilbert Casse, Berend van der Wal and Peter Cundall
1939:
Osaka. Laid down by Nakata Zosensho K.K. as a 889-tons cargo ship for Sanko Kisen K.K.
25 December 1939:
Launched and named CHOKO MARU. [1]
30 April 1940:
Completed and registered at Amagasaki. Her Gross Registered Tonnage (GRT) and Net Registered Tonnage (NRT) respectively are 889-tons and 592-tons. Her call sign is JYVN. [2]
25 September 1941:
Requisitioned by the IJN.
5 October 1941:
Registered as an auxiliary netlayer attached to the Kure Naval District. That same day, Navy (Resv) Lt(jg) Kutsuna Kageyoshi is appointed CO.
30 October 1941:
Conversion for military duty is completed at Kosaki Dock K.K.
31 October 1941:
91st Subchaser Division based at Camranh Bay, French Indochina (now Vietnam) is established under Ordinance No. 1311. Attached to Vice Admiral Ozawa Jizaburo’s (37) Southern Expeditionary Fleet in Rear Admiral (later Vice Admiral) Hiraoka Kumeichi’s 9th Base Force, 91st Subchaser Division also consisting of auxiliary subchasers SHONAN MARU No. 6 and SHONAN MARU No. 7.
25 November 1941:
Rated as auxiliary netlayer No. 911.
1 December 1941:
Rated as 91st Subchaser Division, First Unit. At 1430, arrives at Samah (Sana or Sanya), Hainan Island, China.
2 December 1941:
Departs Samah.
9 December 1941:
Arrives at Singora, Siam (now Songkhla, Thailand).
17 December 1941:
At 2215, gun fires an enemy submarine at 15° E and 7 nautical miles N Pattani lighthouse, Siam.
18 December 1941:
Departs Pattani and arrives at Singora later this day.
21 December 1941:
Departs Singora and arrives at Pattani later that day.
23 December 1941:
Departs Pattani.
24 December 1941:
Arrives at Kota Bharu, British Malaya (now Malaysia). Departs there later this day.
25 December 1941:
Arrives at Singora.
27 December 1941:
Departs Singora.
28 December 1941:
Arrives at Kota Bharu. Departs there and arrives at Singora later that day.
3 January 1942:
91st Subchaser Division is attached to Vice Admiral Ozawa Jizaburo’s (37) First Southern Expeditionary Fleet, 9th Base Force.
5 January 1942:
Departs Singora.
6 January 1942:
Arrives at Kota Bharu.
7 January 1942:
Departs Kota Bharu.
8 January 1942:
Arrives at Singora.
10 January 1942:
Departs Singora.
11 January 1942:
Attached to Anambas Base Force Unit under Malay Command Order No. 15.
12 January 1942:
Arrives at Poulo Condor, French Indochina (now Con Son Island, Vietnam).
24 January 1942:
Departs Poulo Condor.
26 January 1942:
Arrives at Anambas Islands, Netherlands East Indies (now Kepulauan Anambas, Indonesia).
25 February 1942:
91st Subchaser Division is attached to Vice Admiral Ozawa Jizaburo’s (37) First Southern Expeditionary Fleet, 9th Base Force.
28 February 1942:
Departs Anambas Islands.
1 March 1942:
Arrives off Kuantan, British Malaya (now Malaysia).
7 March 1942:
Departs Kuantan waters.
8 March 1942:
Arrives at Anambas Islands. Departs there later this day.
9 March 1942:
Arrives at Singapore.
17 March 1942:
Attached to Penang, British Malaya (now Pulau Pinang, Malaysia) Base Forces under Malaya Army Wireless Letter No. 36. Departs Singapore that same day.
18 March 1942: Operation “U” - The Initial transport operation to Burma:
Arrives at Penang. Departs there later that day escorting the first transport convoy to Burma. The convoy consists of SHUNSEI, YAE, KOAN, TATEISHI, HAVRE (5,467 GRT), HIBURI, HOKUMEI, YAMAZUKI, GLASGOW, SYDNEY, SHINANOGAWA, AOBASAN, KAZUURA, KIZAN, KUSUYAMA, KOTOHIRA, SANKO, SAKITO, SHINAI, SHINRYU, SUMATRA, GENOA, TSUYAMA, TOKIWA, NAKO, NAGARA, NICHIRAN, NAPLES, HARUNA (10,420 GRT), HOFUKU, MYOKO (4,103 GRT), ATLAS, CALCUTTA, KUWAYAMA, MEIGEN, KYUSHU and MOMOYAMA MARUs and six unidentified merchant ships.
20 March 1942:
At 1900, detaches from the convoy with Subchaser Division 91's SHONAN MARU No. 5 and No. 7, light cruisers KASHII and YURA, kaibokan SHIMUSHU, minelayer HATSUTAKA, MineSweepDiv 1's W-1, W-3 and W-4 and auxiliary gunboat EIKO MARU escorting HIROKAWA and KINUGASA MARUs and seven unknown troop transports for Operation ‘D’. The remaining 23 transports and escorts continue on to Rangoon, Burma (now Yangon, Myanmar). Auxiliary seaplane tender SAGARA MARU provides air cover from an area E Nicobars.
23 March 1942: Operation "D" - The Invasion of the Andaman Islands:
From 0400, covers the unopposed landing of one battalion of the IJA 18th Infantry Division at Port Blair.
1 April 1942:
Arrives at Penang.
2 April 1942:
Departs Penang.
5 April 1942:
Arrives at Penang.
15 April 1942:
Departs Penang.
21 April 1942:
Arrives at Penang.
22 April 1942:
Departs Penang.
28 April 1942:
Arrives at Penang.
1 May 1942:
Departs Penang escorting an unidentified transport.
6 May 1942:
Arrives at Penang.
11 May 1942:
Departs Penang.
13 May 1942:
Arrives at Penang.
14 May 1942:
Departs Penang.
17 May 1942:
Arrives at Singapore.
7 June 1942:
Departs Singapore on escort duty.
10 June 1942:
Arrives at Penang.
16 June 1942:
Departs Penang on patrol.
23 June 1942:
Arrives at Penang.
25 June 1942:
Departs Penang on patrol.
30 June 1942:
Arrives at Penang.
2 July 1942:
Departs Penang on Penang Bay entrance patrol and thereafter on escort duty.
17 July 1942:
Arrives at Penang.
18 July 1942:
Departs Penang on escort mission, then on Penang Bay entrance patrol, thereafter on anti-submarine sweep followed by escort duty after which she returns to Penang where she arrives later that day.
1 August 1942:
Departs Penang escorting convoy S-5.
2 August 1942:
Arrives at Penang. Departs later this day on anti-submarine sweep followed by Penang Bay entrance patrol.
5 August 1942:
Arrives at Penang.
7 August 1942:
Departs Penang escorting convoy R-5.
11 August 1942:
Arrives at Penang.
14 August 1942:
Departs Penang on Penang Bay entrance patrol followed by an anti-submarine sweep.
19 August 1942:
Arrives at Penang.
20 August 1942:
Departs Penang escorting auxiliary transport KUNITSU MARU.
27 August 1942:
Escorts an unidentified IJA transport.
29 August 1942:
Arrives at Penang.
30 August 1942:
Departs Penang escorting an unidentified seized ship.
2 September 1942:
Arrives at Penang.
10 September 1942:
Navy (Resv) Lt(jg) Maehara Izuru is appointed CO.
11 September 1942:
Departs Penang.
19 September 1942:
Arrives at Penang.
22 September 1942:
Departs Penang.
25 September 1942:
Arrives at Penang.
5 October 1942:
Departs Penang.
8 October 1942:
Arrives at Penang.
11 October 1942:
Departs Penang escorting convoy S-15 consisting of WALES, SOSHU, CELEBES, KEIFUKU and DURBAN MARUs.
13 October 1942:
Escorts R-15 convoy consisting of KYOKKO, OYO and YUBAE MARUs.
15 October 1942:
COLOMBIA MARU departs Penang and joins R-15 convoy.
16 October 1942:
Explores One Fathom Bank (off Selangor coast), British Malaya (now Permetang Sedepa, Malaysia).
17 October 1942:
Departs One Fathom Bank escorting an S convoy (likely S-16 consisting of MOJI and HEIMEI MARUs).
18 October 1942:
Arrives at Penang.
25 October 1942:
Departs Penang on an anti-submarine sweep.
1 November 1942:
Arrives at Penang.
6 November 1942:
Departs Penang.
9 November 1942:
Arrives at Penang.
10 November 1942:
Departs Penang.
11 November 1942:
Reverses course and returns to Penang.
12 November 1942:
Arrives at Penang.
16 November 1942:
Departs Penang.
18 November 1942:
Arrives at Penang. Enters drydock.
5 January 1943:
Departs Penang on escort duty, possibly NICHIMEI MARU heading to Singapore.
9 January 1943:
Departs Singapore with subchaser CH-8 escorting convoy S-23 bound for Rangoon and consisting of MOJI and NICHIMEI MARUs carrying IJA troops.
10 January 1943:
Arrives at Port Swettenham, British Malaya (now Port Klang Malaysia).
11 January 1943:
Departs Port Swettenham.
12 January 1943:
Arrives at Penang.
20 January 1943:
Departs Penang.
21 January 1943:
Arrives at Penang.
29 January 1943:
Departs Penang for participation in an army artillery exercise. Returns to port later that day.
30 January 1943:
Departs Penang for participation in an army artillery exercise. Returns there later this day.
2 February 1943:
Departs Penang.
3 February 1943:
Arrives at Penang.
6 February 1943:
Departs Penang escorting a convoy, possibly including auxiliary transport TAMISHIMA MARU.
8 February 1943:
Arrives at the 10° latitude. Continues escorting the convoy.
10 February 1943:
Arrives at Penang.
24 February 1943:
Departs Penang.
26 February 1943:
Arrives at Sabang, Sumatra, Netherlands East Indies (now Indonesia). Departs there later that day.
28 February 1943:
Arrives at Penang.
9 March 1943:
Departs Penang on escort duty.
11 March 1943:
Arrives at Sabang. Departs there later this day.
13 March 1943:
Arrives at Penang.
15 March 1943:
Departs Penang on escort mission.
17 March 1943:
Arrives at Sabang. Departs there later that day.
18 March 1943:
Arrives at Penang.
8 April 1943:
Departs Penang on an anti-submarine sweep.
14 April 1943:
Arrives at Penang.
21 April 1943:
Departs Penang on an anti-submarine sweep.
22 April 1943:
At 0930, spots LtCdr John A. Fitzgerald's (USNA '31) USS GRENADIER (SS-210) immobilized on surface with an irreparable propulsion system [3] and begins firing at the submarine. The skipper "didn't think it advisable to make a stationary dive in 280 feet of water without power," and the crew began burning confidential documents prior to abandoning ship. A Japanese plane attacked the stricken submarine, but USS GRENADIER, though dead in the water and to all appearances helpless, blazed away with her MGs. She hit the plane on its second pass. As the damaged plane veered off, its torpedo landed about 200 yards (200 m) from the boat and exploded. Opening all vents, USS GRENADIER’s crew abandoned ship and watched her sink to her final resting place at 07-09N, 98-39E. CHOKO MARU picked up eight officers and 68 enlisted men and took them to Penang.
23 April 1943:
Arrives at Penang. Departs later this day on an anti-submarine sweep.
1 May 1943:
Arrives at Penang. 91st Subchaser Division is dissolved under Subchaser Division Formation Ordinance No. 831. Attached to 9th Subchaser Division under Order No. 834.
12 May 1943:
Departs Penang on escort mission.
14 May 1943:
Arrives at Penang.
16 May 1943:
Departs Penang on escort mission.
19 May 1943:
Arrives at Gaboi(y) (Jaboi) Pulau Weh, Sumatra, Netherlands East Indies (now Pulau We, Indonesia). Departs there later that day.
23 May 1943:
Arrives at One Fathom Bank. Departs there later this day.
24 May 1943:
Arrives at Penang.
30 May 1943:
Departs Penang for One Fathom Bank escorting auxiliary minesweeper tender EIKO MARU, and performs other escort duties.
1 June 1943:
Arrives at Penang.
8 June 1943:
Departs Penang.
9 June 1943:
Arrives at Singapore.
9 ~ 27 June 1943:
In drydock for repairs.
27 June 1943:
Departs Singapore.
29 June 1943:
Arrives at Penang.
30 June 1943:
Departs Penang escorting an R convoy.
9 July 1943:
Departs One Fathom Bank.
10 July 1943:
Arrives at Penang.
11 July 1943:
Departs Penang to escort inbound auxiliary water tanker KISOGAWA MARU arriving from Sabang.
13 July 1943:
Arrives at Penang.
15 July 1943:
Departs Penang escorting auxiliary water tanker KISOGAWA MARU bound for Singapore.
17 July 1943:
Arrives at Penang.
22 July 1943:
Departs Penang.
23 July 1943:
Arrives at Phuket, Siam (now Thailand).
24 July 1943:
Escorts an R convoy likely consisting of GENKAI, TAMATSU and YAMABUKI MARUs escorted by auxiliary gunboat CHOSA MARU.
28 July 1943:
Departs One Fathom Bank.
29 July 1943:
Arrives at Penang.
1 August 1943:
Attached to the 9th Escort Division under Instruction No. 1571.
6 ~ 13 August 1943:
Carries out anti-submarine sweeps.
12 August 1943:
At 04.13N 100.17E in the Malacca Stratits detects an enemy submarine, and together with CH-7 launches a depth charge attack, without result.
19 ~ 28 August 1943:
Performs transport duties.
29 August 1943:
Performs anti-submarine sweeping.
18 October 1943:
At 1800, departs Penang for Singapore escorting unknown ship/s.
10 February 1944:
Performs anti-submarine sweeping.
12 February 1944:
NW of Penang. Together with subchaser CH-8 and an unidentified subchaser, chases Lt. D.S.M. Verschoyle-Campbell’s British submarine HMS STONEHENGE (P-232) after her unsuccessful attack on a vessel identified as a seaplane tender by Verschoyle at 1556. After an unsuccessful depth-charge attack at which the three subchasers drop more than 30 DCs, Verschoyle tries again. At 1655, only one subchaser remained with the target ship. The other two subchasers are seen hunting northward. At 1810, the target ship has stopped and the remaining subchaser has gone. At 1853, 05-45N, 99-52E, Verschoyle fires one torpedo at the target ship which hits amidships. CHOKO MARU subsequently sinks.
3 May 1947:
Removed from the Navy’s list under instruction No. 327.
Authors' Notes:
[1] Not to be confused with the other ships bearing the same name like Teikoku Kisen’s cargo (20’, 6783 GRT), auxiliary transport (39’, 3,515 GRT), auxiliary stores ship (24’, 1,794 GRT), raised transport (ex-British HSIN YANGTSE) (27’, 921 GRT) and Taiyo Gyogyo’s cargo ship (40’, 842 GRT).
[2] NRT is a ship's cargo volume capacity expressed in "register tons", one of which equals to a volume of 100 cubic feet (2.83 m3). It is calculated by subtracting non-revenue-earning spaces i.e. spaces not available for carrying cargo, for example engine rooms, fuel tanks and crew quarters, from the ship's gross register tonnage (GRT). Net register tonnage (NRT) is not a measure of the weight of the ship or its cargo, and should not be confused with terms such as deadweight tonnage or displacement.
[3] Running on the surface at dawn 21 Apr ‘43, USS GRENADIER spotted, and was simultaneously spotted by a Japanese plane. The submarine dived, and as it passed 130 feet (40 m) her XO commented, "We ought to be safe now." Just then, explosions rocked USS GRENADIER and heeled her over 15 to 20°. Power and lights failed completely and the fatally wounded ship settled to the bottom at 270 feet (82 m). She tried to make repairs, while a fierce fire blazed in the maneuvering room.
After 13 hours of sweating it out on the bottom, USS GRENADIER managed to surface after dark to clear the boat of smoke and inspect damage. The damage to her propulsion system was irreparable. Attempting to bring his ship closer to shore so that the crew could scuttle her and escape into the jungle, her skipper even tried to jury-rig a sail. But the long night's work proved futile.
Thanks go to Gengoro S. Toda of Japan.
- Gilbert Casse, Berend van der Wal and Peter Cundall.
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