IJN Subchaser CH-18
Tabular Record of Movement
© 2005-2016 Bob Hackett, Sander Kingsepp and Peter Cundall
Tsurumi. Laid down at the Nippon Kokan, K.K shipyard.
23 April 1941:
Launched and numbered CH-18
31 July 1941:
Completed and registered in the IJN.
8 December 1941:
Takao, Formosa. Assigned to Rear Admiral (later Vice Admiral) Hirose Sueto's (39)(former CO of AOBA) 2nd Base Force of Vice Admiral Takahashi Ibo's (36) (former CO of KIRISHIMA) Third Fleet. Attached to the Philippines Seizure Force in Cdr Ota's SubChasDiv 21 with CH-4, CH-5, CH-6, CH-16 and CH-17.
22 December 1941: The Invasion of the Philippines:
Lingayen Gulf. Three echelons of 76 transports carrying the main part of LtGen Homma Masaharu's Fourteenth Army land at Lingayen. SubChasDiv 21 escorts Rear Admiral Hirose's third echelon of 22 transports from Keelung, Formosa.
24 February 1942: Operation "J" - The Invasion of Java, Netherlands East Indies:
Participates in the landings at Bantam Bay, near Batavia (Jakarta), Java.
8-12 March 1942:
Participates in the capture of Surabaya, Java.
1 May 1942:
Reassigned to SubChasDiv 21 attached directly to HQ, Combined Fleet.
28 May 1942: Operation “MI” – The Battle of Midway:
CH-18 is attached to Vice Admiral (later Admiral) Kondo Nobutake’s (35) (former CO of KONGO) Midway Invasion Force in Captain (Rear Admiral, posthumously) Miyamoto Sadachika's (39)(former CO of YAEYAMA) 16th Minesweeper Unit consisting of auxiliary minesweepers TAMA MARU No. 3, SHONAN MARUs No. 7 and No 8, subchasers CH-16 and CH-17. Departs Saipan for Wake, enroute to Midway.
4 June 1942:
At 0843, a PBY "Catalina" flying boat discovers Captain Miyamoto's minesweeper group heading towards Midway.
5 June 1942:
At 0255, after receiving word that the occupation of Midway has been canceled, retires north.
10 June 1942:
At 0940 CH-17 and CH-18 arrive at Nagaura.
12 June 1942:
At 1200 CH-17 and CH-18 depart Nagaura.
15 June 1942:
At 1655 CH-17 and CH-18 arrives at Nagaura.
16 June 1942:
At 0810 CH-17 departs Nagaura. CH-18 departs soon adfter at 0900.
23 June 1942:
At 1900 CH-17 and CH-18 arrive at Nagaura.
24 June 1942:
At 1440 CH-17 and CH-18 departs Nagaura and soon after CH-17 only arrives at Uraga.
6 July 1942:
At 1420 arrives at Nagaura.
7 July 1942:
At 1240 departs Nagaura.
14 July 1942:
Reassigned to Vice Admiral Mikawa Gunichi's (38) 8th Fleet with the 8th Base Force's SubChasDiv 21 at Rabaul with CH-4, CH-5, CH-6, CH-16 and CH-17.
16 July 1942:
At 1725 arrives at Nagaura.
29 July 1942:
CH-17and CH-18 depart Nagaura.
14 August 1942:
Under repairs at Truk.
20 August 1942:
Arrives Emidj from Truk escorting SHOJU MARU.
18 October 1942:
At 1320 arrives from Shortlands escorting Naval transport NANKAI MARU.
23 October 1942:
At 1900 CH-17 and CH-18 depart Rabaul on an escort mission.
29 October 1942:
At 1200 both CH-17 and CH-18 arrive back at Rabaul.
30 October 1942:
At 1145 CH-17 and CH-18 depart on an escort mission.
1 November 1942:
At 1105 CH-18 arrive back at Rabaul.
3 November 1942:
At 1720 CH-17 and CH-18 depart Rabaul on an escort mission to Shortland, possibly YAMASHIMO MARU that was also escorted by CH-28.
7 November 1942:
At 1100 CH-17 and CH-18 arrive back at Rabaul.
10 November 1942:
At 2140 CH-18 departs Rabaul on an escort mission.
13 November 1942:
At 0800 arrives back at Rabaul.
16 November 1942:
At 0700 departs Rabaul on an escort mission.
17 November 1942:
At 0740 arrives back at Rabaul.
21 November 1942:
At 1600 departs Rabaul on an escort mission with CH-16.
23 November 1942:
At 1200 the escorts meet up with incoming Army convoy A (No.8 Military Movement) consisting of GENMEI and KOCHI MARUs then escorted by auxiliary gunboat CHOAN MARU No. 2 GO.
24 November 1942:
At 1500 the convoy arrives at Rabaul.
27 November 1943:
At 1620 departs Rabaul on an escort mission to Shortland.
2 December 1942:
At 0500 CH-18 and CH-28 arrive back at Rabaul probably escorting KAMOI MARU.
5 December 1942:
At 0830 departs Rabaul on an escort mission.
8 December 1942:
CH-2 departs Surabaya with minesweeper W-11 and auxiliary gunboat OKUYO MARU escorting the Oki convoy consisting of an unidentified number of merchant ships. This will later involve CH-18
9 December 1942:
At 0400 arrives back at Rabaul.
13 December 1942:
From Oki convoy Minesweeper W-11 is detached.
14 December 1942:
At 0520 CH-18 departs Rabaul on escort mission, presumably to meet up with Oki convoy. From Oki Convoy itself Subchaser CH-2 is detached.
15 December 1942:
Subchaser CH-20 joins Oki convoy.
18 December 1942:
Subchaser CH-18 joins Oki convoy and CH-20 is detached.
22 December 1942:
An unknown submarine attacks the convoy. OKUYO MARU drops three depth charges. Later that day the convoy arrives at Rabaul. There is a strong inference that CH-16 and CH-17 also join the convoy at some point.
23 December 1942:
At 0200 CH-16, CH-17 and CH-18 all arrive back at Rabaul together.
25 December 1942:
At 2035 CH-17 and CH-18 depart Rabaul on an escort mission.
29 December 1942:
At 1400 arrives back at Rabaul (CH-17 had arrived back earlier the same day).
3 January 1943:
At 0500 departs Rabaul on an escort mission.
7 January 1943:
At 0615 arrives back at Rabaul.
9 January 1943:
At 1715 departs Rabaul on patrol.
10 January 1943:
At 2100 arrives back at Rabaul.
11 January 1943:
At 0700 CH-16, CH-17 and CH-18 depart Rabaul on an anti submarine sweep.
12 January 1943:
At 1030 arrives back at Rabaul (CH-16 and CH-17 arrived back later that day). At 1700 CH-18 departs on an escort mission.
17 January 1943:
At 0700 arrives back at Rabaul.
20 January 1943:
At 1500, CH-18 and CH-22 depart Rabaul for Truk escorting a convoy consisting of KAIHEI, TAIFUKU and NANKAI MARUs.
22 January 1943:
Steffen Straits near Kavieng, New Ireland. CH-18 and CH-22 rendezvous with convoy "D" inbound from Truk consisting of TAIMEI, KAMO, MACASSAR, SHINRYU and SHICHISEI MARUs and an unidentified ship escorted by CH-12 and auxiliary gunboat CHOKO MARU No. 2. CH-18 and CH-22 escort convoy "D" to Rabaul. CH-12 and CHOKO MARU No. 2. detach to escort an outbound convoy. 
24 January 1943:
At 0130 arrive at Rabaul.
25 January 1943:
At 1400, departs Rabaul escorting KIKUGAWA MARU en route to Saipan.
27 January 1943:
At 1700, at 02-15N, 149-00E, CH-18 breaks off escorting KIKUGAWA MARU, then makes a rendezvous at 00-30N, 149-40E with inbound convoy "U" consisting of YAMATO, MEIKAI, MOMOHA and INDUS MARUs and relieves destroyer YUNAGI. CH-18 escorts the convoy to Rabaul.
31 January 1943:
At 0120 Convoy "U" arrives at Rabaul.
1 February 1943:
At 1730 departs Rabaul on an escort mission.
5 February 1943:
At 0900 arrives back at Rabaul.
8 February 1943:
At 0430 departs Rabaul on an escort mission possibly of Naval transport MIKAGE MARU No.20 part way to Palau.
11 February 1943:
At 0800 arrives back at Rabaul possibly escorting transports AKIBASAN MARU and KUNISHIMA MARUs part way from Palau and then Kavieng.
13 February 1943:
At 1700 departs Rabaul on an escort mission.
15 February 1943:
At 0715 arrives back at Rabaul.
16 February 1943:
At 1000 departs Rabaul. Later that day Off Cape St. George, New Britain. At 1528, CH-18 and torpedo boat HIYODORI are escorting converted transport NOSHIRO MARU enroute from Rabaul to Kolombangara, when four torpedo tracks are sighted off the starboard beam, 4,000 meters away. All ships execute evasive maneuvers and no hits are scored.
Six minutes later, a floatplane of the 958th Naval Air Group providing air cover, probably an Aichi E13A1 "Jake”, locates the attacking submarine and drops several depth charges. At 1540, HIYODORI starts another attack, dropping nine DCs. Six minutes later, CH-18 locates the target and attacks it with six DCs. An oil slick appears and the upper section of a submarine conning tower surfaces for a few moments, disappearing before it can be targeted. Four minutes later, CH-18 starts another run-in, dropping three DCs in the middle of the steadily expanding oil slick.
At 1642, debris is sighted at 05-05S, 152-37E. HIYODORI's crew recovers several items, including a life raft with "Philadelphia Navy Yard" printed on it. Possibly, the submarine was LtCdr John A. Bole’s (USNA ’28) USS AMBERJACK (SS-219), lost with all 73 hands at about this time and place. 
19 February 1943:
At 0600 arrives back at Rabaul.
21 February 1943:
At 1645 departs Rabaul on an escort mission.
25 February 1943:
At 0715 arrives back at Rabaul.
2 March 1943:
At 1150 departs Rabaul on an escort mission.
6 March 1943:
At 0915 both CH-18 and CH-22 arrive back at Rabaul.
9 March 1943:
At 1530, CH-18 and CH-22 depart Rabaul escorting Wewak No. 1 convoy consisting of TAISEI, NISSHU, TOHO, TAIYU, KOSEI and TOKOHIME MARUs.
14 March 1943:
At 1113, arrives at Wewak.
2 April 1943:
At 1230 arrives at Rabaul.
7 April 1943:
CH-18 and CH-39 depart Rabaul for Palau escorting TOYU, KOFUKU, AKAGISAN and OYAMA (YUZAN) MARUs.
9 April 1943:
250 miles NNW of Kavieng, New Ireland. At about noon, the convoy is attacked by LtCdr (later Rear Admiral) Bernard F. McMahon's (USNA ’31) USS DRUM (SS-228) at 00-38N, 150-17E. McMahon fires three torpedoes at OYAMA MARU and gets one hit that sinks her. Four crewmen are killed.
10 April 1943:
In the morning, McMahon attacks the convoy again. He torpedoes and damages AKAGISAN MARU, but she does not sink. The convoy diverts from Palau to Truk.
13 April 1943:
At 0810 arrives at Truk.
16 April 1943:
At 1630 CH-18 departs Truk on an escort mission.
18 April 1943:
200 miles NNW of Mussau Island, Bismarcks. At about 1230, LtCdr (later Rear Admiral) Bernard F. McMahon's (USNA ’31) USS DRUM attacks a convoy from Palau also consisting of TEIKAI (ex German FULDA), KURAMASAN, NIKKI MARUs and BANSHU MARU No.? and torpedoes ammunition ship NISSHUN MARU that sinks about 1300 at 01-55N, 148-24E. Loaded with foodstuffs and general cargo, the ship takes down 35 crewmen. CH-18 rescues the survivors that include a number of impressed Korean "comfort" women.
22 April 1943:
At 0445 arrives at Rabaul. The rest of the convoy arrives two days later.
25 April 1943:
At 1440 CH-16 and CH-18 depart Rabaul to Palau escorting a convoy consisting of the tanker SAN CLEMENTE MARU and cargo ships MIYAURA, ROKKOSAN, RISSHUN, RAKUTO, TOUN and HOEI MARUs. Later the convoy is joined by CH-37 and CH-16 is detached.
4 May 1943:
At 0140 CH-18 arrives back at Rabaul.
7 May 1943:
At 0430 departs Rabaul on an escort mission.
16 May 1943:
At 0500 arrives back at Rabaul. At 1200 departs Rabaul in an anti submarine sweep.
21 May 1943:
At 0430 arrives back at Rabaul.
22 May 1943:
At 1500 departs Rabaul in convoy consisting of MEIZAN, KANJO, YUBAE and HIBURI MARUs escorted by destroyer YUNAGI and sub-chasers CH 18 and CH 39.
26 May 1943:
At 1800 YUNAGI detaches from the convoy.
1 June 1943:
Arrives at Palau.
10 June 1943:
At 1740 arrives at Rabaul.
19 June 1943:
At 1240 departs Rabaul on an escort mission, likely of TAISEI MARU to Wewak.
2 July 1943:
At 0645 arrives back at Rabaul.
4 July 1943:
At 0500 departs Rabaul on a patrol.
6 July 1943:
At 0530 arrives back at Rabaul. At 1610 CH-17 and CH-18 depart Rabaul on an escort mission.
10 July 1943:
At 1650 arrives back at Rabaul.
12 July 1943:
At 0610 departs Rabaul on an escort mission.
14 July 1943:
At 1115 returns to Rabaul.
15 July 1943:
At 1220 departs Rabaul on an escort mission.
28 July 1943:
CH-10, CH-18 and CH-23 depart Palau escorting convoy So-807 consisting of EHIME, KAZAN and KOZAN mARUs and two unidentified merchant ships.
5 August 1943:
At 0825 arrive at Rabaul.
5 August 1943:
At 0825 arrives at Rabaul.
10 August 1943:
At 1210 CH-18 and CH-37 depart Rabaul escorting convoy O-005 consisting of Army repair ship MINRYO MARU and four unidentified merchant ships to Palau.
18 August 1943:
Arrives at Palau.
20 August 1943:
CH-18 and CH-37 depart Palau escorting convoy So-003 consisting of TAGA, MITO and TOYAMA MARUs.
27 August 1943:
At 0550 the convoy arrives at Rabaul.
31 August 1943:
At 1200 CH-18 and CH-37 depart Rabaul on an escort mission.
9 September 1943:
At 0940 CH-18 arrives back at Rabaul.
11 September 1943:
At 1143 departs Rabaul with CH-18 to meet up with convoy So-105 consisting of MEXICO, TAITO, TAIAN, TOTAI and YAWATA MARUs.
18 September 1943:
At 0545 CH-18 arrives back at Rabaul.
22 September 1943:
At 1400 CH-18 and CH-37 departs Rabaul escorting Convoy O-206 consisting of TOYU MARU and four unidentified merchant ships part way to Palau).
30 September 1943:
At 1200 arrives back at Rabaul.
25 October 1943:
CH-17 and CH-18 depart Rabaul escorting convoy O-505 consisting of KOSEI, SAN FRANCISCO, TAITO MARUs and two unidentified merchant ships.
2 November 1943:
Arrives at Palau.
20 November 1943:
CH-18 departs Rabaul with CH-17 escorting a convoy consisting of two unidentified ships and 5,824 GRT cargo ship NAPLES MARU carrying 517 troops of the IJA 51st Division and of the 4th Air Group.
N of New Ireland. Later that day, the convoy is attacked by a PBY "Catalina" that bombs and sinks NAPLES MARU at 03-21S, 151-41E. 121 troops and five of the crew are killed. CH-18 and CH-17 rescue the survivors.
8 January 1944:
CH-18 departs Rabaul with CH-17 escorting convoy O-805 consisting of KOYO, PACIFIC, MEXICO, CEYLON and NAGISAN MARUs.
15 January 1944:
At 1230, the convoy arrives at Palau.
19 January 1944:
At 1200, CH-17 and CH-18 depart Palau for Rabaul escorting convoy SO-903 consisting of TONEI and NIPPONKAI MARUs and TAKATORI MARU No. 2 towing a target barge.
26 January 1944:
Arrives at Rabaul.
Reassigned to the 5th Base Force. Escorts convoys between Saipan and the mainland.
14 March 1944:
At 1540, CH-18 and CH-17 and minesweeper W-21 depart Saipan 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 from convoy 4313-B that arrives safely at Chichi-Jima on 20 Mar '44.
7 April 1944:
At 0540 departs Saipan in convoy No. 4407 consisting of ASAKA MARU and MANJU (ex SANTOS) MARU, escorted by kaibokan NOMI and submarine chasers CH-16 and CH-18.
12 April 1944:
At 1600 arrives at Yokosuka. Returns for Yokosuka for repairs and maintenance.
28 April 1944:
CH-18 and CH-16 depart Tokyo escorting 15-ship convoy Higashi-Matsu No. 7 consisting of TATSUHARU, MITAKESAN, ASAHISAN, OKINAWA, SANJU, BINGO, MEIRYU, MOJI and MIHO MARUs bound for Saipan, ASAKA MARU and LST No. 128 and No. 150 bound for Palau, KOSHIN and MUTSUYO MARUs bound for Yap Island and TAITO MARU bound for Chichi-Jima. The convoy is also escorted by kaibokan CD-12, CD-18, CD-22 and NOMI and minesweeper W-27.
29 April 1944:
At 1230 W-27 is detached and returns to Nagaura.
The convoy's participants arrive safely at their destinations.
6 June 1944:
CH-18, destroyer MATSUKAZE, kaibokan AMAKUSA, NOMI, OKI, subchaser CH-16, torpedo boat CHIDORI (part way only), and auxiliary minesweepers SHOWA MARU No. 7 and SHOWA MARU No. 8 depart Yokohama for Saipan escorting convoy No. 3606 consisting of SUGIYAMA, SHINROKU, KANSEISHI, KAIKO, AWAJI, YAMATAMA, DAITEN, RYUKO, TOYOKAWA, TOKO, SHOZUI, MIHO and HAKUYO MARUs. Soon after leaving SUGIYAMA MARU is attacked and damaged by LtCdr (later Captain) James B. Grady's (USNA ’33) USS WHALE (SS-239) at 31-06N, 142-24E, but the ship is taken in tow.
9 June 1944:
35 miles E of Chichi-Jima. At about 0400, LtCdr Edmund K. Montross' (USNA ’35) USS SWORDFISH (SS-193) torpedoes and sinks MATSUKAZE at 26-59N, 143-13E. AMAKUSA rescues nine survivors. The escorts depth charge USS SWORDFISH unsuccessfully. The convoy steams to Chichi-Jima arriving later that day. It is decided to unload the ships there, rather than to proceed to Truk as originally planned.
14 June 1944:
CH-16 and CH-18 depart Chichi-Jima with auxiliary netlayer KOGI MARU and auxiliary minesweeper TOSHI MARU No. 5. escorting the "Yaei Maru" convoy consisting of YAEI, TATSUEI and KYUSHU MARUs and UNKAI MARU No.10.
15 June 1944:
At 0800, torpedo boat CHIDORI and minesweeper W-25 join the escort.
16 June 1944:
In a raging storm, CH-16, TATSUEI MARU, UNKAI MARU No. 10 and KOGI MARU are separated from the convoy and steam together.
18 June 1944:
Arrives at Nagaura and Yokosuka, Tokyo Bay.
26 June 1944:
Transfers to Yokosuka.
28 June 1944:
CH-18, CH-16, minesweeper W-25, minelayer SARUSHIMA and auxiliary minesweeper TOSHI MARU No. 5 depart Yokosuka for Chichi-Jima escorting convoy No. 3628 consisting of SHIMA, TATSUEI, SHOZUI, TAIKO and KAIKO MARUs and UNYO MARU No. 8.
2 July 1944:
Convoy No. 3628 arrives at Chichi-Jima and begins to unload.
4 July 1944:
Off Chichi-Jima. Convoy No. 3628 is attacked and virtually destroyed by Task Force 58's carrier planes. CH-18 is damaged in the attacks but departs Chichi-Jima.
CH-18 is reassigned directly to the Combined Fleet. Undergoes battle-damage repairs.
6 August 1944:
At 0900, CH-18 and CH-17 depart Kagoshima, Kyushu for Keelung, Formosa escorting 15-ship convoy KATA-626. Other escorts include torpedo boats TOMOZURU and MANAZURU, minelayers NUWAJIMA, TSUBAME, NIIZAKI, auxiliary minesweepers SHONAN MARU No. 16, HAKATA MARU No. 6, TAIAN, HIMESHIMA and SEKI MARUs.
9 August 1944:
At 1830, arrives at Naha, Okinawa. CH-18 returns to Kagoshima.
17 August 1944:
At 1900, subchasers CH-18 departs Kagoshima with kaibokan CD-30, torpedo boat TOMOZURU, minelayers NUWAJIMA, TSUBAME, NIIZAKI, auxiliary minesweepers TAKUNAN MARUs No. 1 and No. 3, SHONAN MARU No. 16, CHITOSE and HOEI MARUs escorting convoy KATA-717 consisting of ESASHI, UJINA, UNTEN, HIKOSAN, KOTSU, DAIBOSHI, MAKO, MIKAGE, KORYU, SHIROTAE, TAIKYU, TAISHIN, DAITOKU, DAIYA, DAISHIN, BRAZIL, HOKUYU, SHINKO and WASHIN MARUs, HOEI MARU No.2, an unknown ship called UBUYAMA MARU and four unidentified ships.
19 August 1944:
At 1200, arrives at Naha. Most ships in the convoy stop and unload. Later that day CH-18 meets up convoy TAKA-708 consisting of TAIKAI MARU and 22 unidentified merchant ships escorted by CH-17 and CH-49. torpedo boat convoy MANAZURU, minelayers NIIZAKI, TSUBAME and auxiliary minesweepers SEKI MARU, HIMESHIMA MARU, CHOUN MARU No.8, TOSHI MARU No. 7, SHONAN MARU No. 16 and TAKUNAN MARU No.1 and auxiliary patrol boats CHOUN MARU No. 13, TAISEI MARU No. 5 and TAIAN MARU. The convoy proceeds to Kagoshima.
21 August 1944:
DAIYA, HOKUYU and WASHIN MARUs the remnants of convoy KATA-717 depart Naha with an unknown escort proobably including CH-17 and CH-18.
22 August 1944:
DAIYA MARU is detached at Miyako-Jima.
23 August 1944:
The convoy arrives at Keelung.
28 August 1944:
At 1200, CH-18, CH-17 and CH-49 depart Kagoshima for Keelung escorting convoy KATA-827 consisting of TSUKUSHI MARU No. 3, DOSHI, DAISHIN, ISSHIN, KONZAN, NANYO, HAKUYO, AMOY, KEIZAN, KEIUN, KOTSU and SHOKYU MARUs, NANKO MARU No.1, HORAI MARU No.6, HORAI MARU No.7, and 17 other unidentified ships. Other escorts include torpedo boat MANAZURU, minelayer NIIZAKI, auxiliary netlayer SHINTO MARU No. 2, auxiliary subchaser CHIKUTO MARU, auxiliary minesweepers SHONAN MARU No. 16, HOEI MARU and auxiliary HOKOKU MARI No. 3.
30 August 1944:
Departs Naha with additional ship KORYU MARU having joined. CH-18 returns to Kagoshima having met up with convoy TAKA-708 consisting of twenty two unidentified merchant ships also escorted by torpedo boat MANZURU, submarine chasers CH-17 and CH-49, auxiliary minesweepers SEKI and HIMESHIMA MARUs, TOSHI MARU No. 7, CHOUN MARU No. 8, SHONAN MARU No. 16 and TAKUNAN MARU No. 1, and auxiliary patrol vessels TAIAN MARU, CHOUN MARU No. 13 and TAISEI MARU No. 5.
10 October 1944:
At 0600, CH-18, CH-17, CH-23, CH-28 and kaibokan KASADO depart Moji for Manila escorting convoy MOMA-05 consisting of DAIHAKU, KOMEI, TENSHO, DAISHO, TATSUURA, TAIYO, ESASHI, DORYU, PACIFIC, AOKI (ex Italian AMBA ALAGI), TAIZAN MARU (ex British ST QUENTIN), SAIHO and SUGIYAMA MARUs. The convoy is carrying about 10,000 reinforcements for the Philippines.
16 October 1944:
At 1820 convoy MOMA-05 departs Imari Bay.
21 October 1944:
At 1600, arrives at Takao, Formosa. KASADO is detached.
23 October 1944:
At 0900, departs Takao and sheltered in bay on S Formosa sailing at 2300.
24 October 1944:
At 1830, arrives Sabtang Island anchorage.
25 October 1944:
At 0400, departs Sabtang anchorage. At 1800 arrives at Musa.
26 October 1944:
At 0403, the convoy is attacked by LtCdr (later Rear Admiral) Maurice Rindskopf's (USNA ’38) USS DRUM (SS-228) at 19-30N, 120-44E. Rindskopf fires three torpedoes by radar bearings at DAISHO MARU and gets two hits that sink her. She takes down about 1600 men, most of whom belonged to the 57th Independent Brigade and 10th Maritime Advance Battalion.
At 0655, Rindskopf torpedoes and damages DAIHAKU MARU at 19-07N, 120-42E. The forepart sinks, although the aft part remains afloat. She is successfully beached in Lapoc Bay and later abandoned. USS DRUM also attacks TATSUURA and TAIYO MARUs with uncertain results.
At about 0710, W of Dalupiri Island LtCdr Richard W. Peterson's USS ICEFISH (SS-367) torpedoes TAIYO MARU. A cargo of gasoline she is carrying for "kaiten" human-torpedoes ignites and sends flames hundreds of feet into the air. At 0730, TAIYO MARU sinks. About 2200 troops on board together with 17 gunners and 13 crewmen are killed, also lost are 22 landing craft, 26 horses and 21 motor vehicles.
28 October 1944:
At 1230, anchors in Lapoc Bay.
29 October 1944:
At 0700, departs Lapoc Bay. At 1600, arrives at N San Fernando.
30 October 1944:
At 0700, departs N San Fernando. At 1600. arrives at Santa Cruz.
31 October 1944:
At 0500, departs Santa Cruz. At 0950, KOMEI MARU is torpedoed and sunk by LtCdr Enrique D. Haskin's USS GUITARRO (SS-363) at 15-18N, 119-50E. The ship was loaded with 3500 M3 of goods and 775 troops; and 346 troops, three armed escort and 10 of the crew are killed. A few minutes later, at 1010, PACIFIC MARU is also torpedoed and sunk by GUITARRO at 15-15N, 119-56E. At the time the ship carrying 300 Naval landing troops and war supplies. 24 soldiers, 27 gunners and 23 crewmen are killed.
1 November 1944:
At 0400, arrives at Manila.
5 November 1944:
At 0500 CH-18 departs Manila with kaibokan CD-18 and CD-26 and subchasers CH-17, CH-23, CH-37 and CH-38 escorting convoy MATA-31 consisting of TATSUHARU and DORYO MARUs and five unidentified merchant ships.
6 November 1944:
At 1055, an enemy submarine is sighted at 16-11N, 109-06E. At 1650 DORYO MARU breaks down and is taken under tow.
7 November 1944:
At 1715 the convoy puts in to Santa Cruz for shelter.
8 November 1944:
At 0730 CD-26 and CH-18 departs Santa Cruz. At 1600 CD-26 and CH-18 arrives at San Fernando. At 1930 departs San Fernando escorting the damaged cruiser AOBA.
11 November 1944:
At 2330 arrives at Takao.
13 November 1944:
At 1000 departs Takao.
14 November 1944:
At 0500 arrives at Sabtang Island and rejoins MATA-31 which departs later that day.
15 November 1944:
At 1200 arrives at Takao.
19 November 1944:
At 2038 CH-17, CH-18, CH-37 and CH-38 depart Takao to sweep in advance of convoy TAMA-31B departing Currimao.
20 November 1944:
At 1530 arrive back at Takao.
23 November 1944:
At 1530, CH-18, CH-17, CH-37 and CH-38 depart Takao escorting convoy TAMA-32A consisting of AKAGISAN, HAGIKAWA, SORACHI, JINYO, NICHIYO, SHOEI, WAYO, MINO, SHIROUMA and SHONAN MARUs and BANSHU MARU No. 6 and kidotei (Army landing ship) SS No. 6 also escorted by old destroyer KURETAKE, kaibokan CD-1, CD-3, CD-8, CD-28 and CD-54. Anchors along the coast soon after leaving.
24 November 1944:
At 0400, departs Formosan coast.
25 November 1944:
At 2200, arrives at Musa Bay, Fuga Island.
27 November 1944:
At 0400, departs Musa Bay. At 1645, arrives at Lapoc Bay.
28 November 1944:
At 0600, departs Lapoc Bay. At 1800, arrives at N San Fernando.
29 November 1944:
At 0600, departs N San Fernando.
30 November 1944:
At 0500, arrives at Manila.
5 December 1944:
At 0950, SubChasDiv 21's CH-18 and CH-38 depart Manila escorting convoy TA No. 8 consisting of AKAGISAN, SHIROUMA and NICHIYO MARUs, SHINSEI MARU No. 5 and transport LST No. 11 also escorted by DesRon 31's UME, MOMO and SUGI. News of the American landings at Leyte landing causes the convoy to head for San Isidro, Leyte.
7 December 1944:
At 0900, arrives at San Isidro and commences unloading. At 0930, 70 USAAF B-24 "Liberator" heavy bombers attack. All the convoy's freighters are deliberately beached. All the ships are bombed and destroyed. 350 troops are killed and the bulk of the equipment lost. UME is hit by a dud bomb in the forward engine room. SUGI is strafed and suffers minor damage. The escorts then begin the return voyage alone, but MOMO is later detached to search the landing area. On her return, she grounds on a reef and is damaged.
8 December 1944:
Arrives at Manila.
30 December 1944:
At 0800, CH-18, CH-21, destroyer KURETAKE and three unidentified escorts depart North San Fernando for Takao escorting convoy MATA-38 consisting of MURORAN, TEIKAI (ex German FULDA), KAZUURA and NISSHO MARUs.
Off Santiago Island, Luzon. At 1310, the convoy undergoes a series of air attacks by 26 of Fifth Air Force's B-25 “Mitchell” medium bombers, A-20 “Havoc” light bombers and P-40 “Warhawk” fighters that skip bomb at low level. CH-18 is hit and sunk as are MURORAN and TEIKAI MARUs. The former sinks with 71 crewmen with only three survivors after her part cargo of ammunition explodes; and the latter sinks with 15 gunners, 23 crewmen and 22 other persons on board KIA. The planes also damage KAZUURA and NISSHO MARUs near Lingayen Gulf at 17-11N 120-45E.
During the bombing, LtCdr Charles D. Brown's (USNA ’38) USS RAZORBACK (SS-394) sneaks in and fires six torpedoes at KURETAKE, of which two hit and sink her in the Bashi Channel.
10 March 1945:
Removed from the Navy List.
 Convoy D was actually Part D (the equipment/baggage convoy) of Convoy No. 35 that departed Shanghai to transport the IJA’s 6th Infantry Division via Truk to Guadalcanal (after the decision is made to evacuate Guadalcanal, the convoy’s destination was changed to New Guinea). Part D departed Truk on 20 Jan '43
and arrived at Rabaul on 24 Jan '43 escorted by CH-18, CH-12 and CH-22 and CHOKO MARU No. 2 (and possibly destroyer HAMAKAZE part way).
 No final conclusions can be drawn concerning the identity of the submarine sunk, since USS GRAMPUS (SS-207) was lost in the same area at about the same time.
The authors found no data detailing CH-18's movements during May-October 1943. Readers with
access to such data are requested to post the information on the Discussion and
Questions board or at the IJN Ship Message
Thanks for assistance to Mr. Gilbert Casse of France.
-Bob Hackett, Sander Kingsepp and Peter Cundall.
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