KUSENTEI!

© 2005-2009 Bob Hackett, Sander Kingsepp and Peter Cundall

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1941:
Osaka. Laid down at Hitachi's Sakurajima Ironworks shipyard.

1941:
Osaka. Launched and numbered CH-24.

20 December 1941:
Completed and registered in the Sasebo Naval District.

1942:
Conducts patrols in Tokyo, Izu and Ise Bays.

May 1942:
Assigned directly to the Combined Fleet and attached to SubChasDiv 23 with CH-22 and CH-23.

June 1942:
Arrives at Guadalcanal.

14 July 1942:
Reassigned to Vice Admiral Mikawa Gunichi's 8th Fleet with the 7th Base Force's SubChasDiv 23 at Lae, New Guinea. Escorts convoys between Rabaul and the Solomon Islands.

17 August 1942:
CH-24 departs Rabaul for Basuba with light cruiser TENRYU, subchasers CH-22, CH-23 and minesweeper W-20 escorting a convoy consisting of KAZUURA, RYOYU and KANYO MARUs transporting the 25th Air Flotilla's base supplies.

18 August 1942:
At 1730, arrives at Basuba.

24 August 1942:
CH-24 and CH-22 depart Rabaul with CruDiv 18's TATSUTA and TENRYU and DesDiv 17's HAMAKAZE, URAKAZE and TANIKAZE escorting transports KINAI and NANKAI MARUs.

25 August 1942: Operation "RE" - The Capture of the Allied Airfield at Milne Bay:
After midnight, the transports land 1,200 troops of the Kure No. 5 Special Naval Landing Force at Milne Bay. In the morning the invasion force is bombed by Boeing B-17s and NANKAI MARU and URAKAZE are damaged.

16 February 1943:
Palau. At 0600, a convoy consisting of KANO MARU and five other ships escorted by CH-24 arrives at the W Channel.

12 March 1943:
At 1515, departs Rabaul with the CH-22 to rendezvous with an incoming convoy.

15 March 1943:
NW of the Admiralty Islands. CH-24, CH-22 and destroyer SATSUKI attack and sink a submarine, probably LtCdr George K. MacKenzie's USS TRITON (SS-201) with all 74 hands. [1]

22 March 1943:
Returns to Rabaul.

28 March 1943:
CH-24 and CH-16 depart Rabaul for Palau escorting a convoy consisting of YAMATO, KUROHIME, DENMARK, TAIKO, NAGANO and MAYA MARUs.

29 March 1943:
Late in the afternoon, LtCdr Arnold H. Holtz's USS TUNA (SS-203) sights the convoy, two escorts and two aircraft overhead. Holtz tracks the convoy into and through the night.

30 March 1943:
NE of Manu Island. At 0750, Holtz fires three torpedoes at the largest ship. Two hit and sink KUROHIME MARU at 00-35N, 147-55E.

5 April 1943:
Arrives at Palau.

9 April 1943:
CH-24 departs Palau escorting a convoy consisting of YAMAFUKU, TAIRIN and MADRAS MARUs.

14 April 1943:
Off Truk. MADRAS MARU is torpedoed by LtCdr Louis D. McGregor's old USS PIKE (SS-173) at 125N, 148-22E, but remains navigable.

16 April 1943:
Arrives at Rabaul.

7 June 1943:
Departs Rabaul in convoy in O-704 consisting of HEIMEI, MAKASSAR, KINKASAN and KONAN MARUs escorted by CH-24 and CH-37.

13 June 1943:
Convoy O-704 is intercepted by LtCdr Edward S. Carmick's USS SARGO (SS-188) that begins tracking the convoy.

14 June 1943:
430 miles SE of Palau. That night, Carmick makes a submerged attack. Hew torpedoes and sinks passenger-cargo ship KONAN MARU at 06-05N, 138-25E. The subchasers drop four DCs and cause some damage to SARGO, but later she arrives safely at Midway Island.

15 June 1943:
Arrives at Palau.

9 July 1943:
Departs Palau in convoy N-905 consisting of HOKKO, TOKO, RYOYO, SHOHO and HOKKAI MARUs escorted by CH-24 and CH-22.

12 July 1943:
In separate actions, LtCdr Oscar E. Hagberg's USS ALBACORE (SS-218) and LtCdr Ralph C. Lynch's MINGO (SS-261) attack the convoy unsuccessfully.

13 July 1943:
ALBACORE and LtCdr Rob R. McGregor's GROUPER (SS-214) make further unsuccessful attacks on the convoy.

16 July 1943:
Arrives at Rabaul.

7 August 1943:
At 1100, departs Rabaul in a convoy consisting of NICHIYO and SUMIYOSHI MARUs and HINO MARU No. 5, and Naval stores ship ARASAKI escorted by CH-24 and CH-10.

9 August 1943:
Arrives at Shortland.

20 October 1943:
At 1445, CH-24 and CH-22 depart Rabaul escorting convoy O-006 consisting of fleet oiler TENNAN MARU, IJA cargo ships JOHORE and KAZAN MARUs and HOZUGAWA, BUNZAN and KOSEI MARUs.

23 October 1943:
LtCdr John S. Coye's SILVERSIDES (SS-236) attacks fleet convoy 0-006 At 2245, Coye sinks TENNAN MARU and damages JOHORE and KAZAN MARUs at 02-30N, 144-44E.

24 October 1943:
KAZAN MARU sinks as the result of her damage. CH-24 attempts to scuttle immobilized JOHORE MARU, but fails. Later, SILVERSIDES finishes off JOHORE MARU.

13 November 1943:
At 1200, departs Rabaul in convoy O-305 consisting of HOKKAI, TAISHO, MAKASSAR and LYONS MARUs and HOSHI MARU No. 5 escorted by CH-24 and CH-39. The convoy is shadowed that evening by a USAAF B-24 "Liberator" bomber. [2]

14 November 1943:
At 0003, the B-24 launches a slow low level attack and hits TAISHO MARU amidships in hold No. 3. TAISHO MARU is damaged, but able to return to Rabaul, arriving the following day.

20 November 1943:
Arrives at Palau.

25 November 1943:
Departs Palau in convoy SO-505 consisting of HOKKO, UCHIDE, YURI, COLUMBIA and CLYDE MARUs, escorted by CH-24 and CH-39.

28 November 1943:
LtCdr James W. Davis' USS RATON (SS-270) attacks the convoy. At 1010, YURI MARU is hit by three torpedoes. She blows up and sinks at 01-45N, 141-52E. Davis also hits HOKKO MARU aft and she sinks at the same location. That evening, Davis attacks the convoy again, but is unsuccessful.

29 November 1943:
LtCdr Robert J. Foley's USS GATO (SS-212) attacks the convoy unsuccessfully.

30 November 1943:
GATO launches a second attack. LtCdr Foley torpedoes and sinks IJA transport COLUMBIA MARU at 01-56N, 147-21E. CH-24 counterattacks unsuccessfully.

At 1600, USN codebreakers intercept and decrypt a message from CH-24 that reads: “At 1624 received torpedo attack in 01-54N, 14-20E. COLUMBIA MARU is receiving attack. We are carrying out attack.”

3 January 1944:
CH-24, CH-33 and CH-39 depart Palau in convoy 8031 consisting of oiler OGURA MARU No. 3.

9 January 1944:
Arrives at Truk.

11 January 1944:
CH-24 departs Truk with convoy 4111, consisting of unidentified ships, escorted by destroyer SHIRATSUYU and kaibokan HIRADO. CH-24 escorts the convoy part way, then returns to Truk.

E 13 January 1944:
CH-24 departs Truk for Rabaul escorting convoy O-905 consisting of SHUNKO, HOZUGAWA, MEISHO and KOSEI MARUs.

16 January 1944:
45 miles NW of New Hanover. At about 0230, nine PBY "Catalina" flying boats attack convoy O-905 with bombs and torpedoes. They sink SHUNKO MARU at 02-30S, 149-42E and sink HOZUGAWA and MEISHO MARUs at 02-20S, 149-42E. CH-24 and KOSEI MARU escape undamaged.

15 February 1944:
CH-24 departs Truk to rendezvous 150 miles N of Truk with fleet convoy No. 3206 composed of IJA transports GYOTEN, SHINKYO and TATSUHA MARUs and IJN cargo ships RYUKO and ZUKAI MARUs and escorts inbound from Japan, but the convoy does not show.

17 February 1944: American Operation "Hailstone" - The Attack on Truk:
At 0531 (I), subchaser CH-29 is also ordered to rendezvous at sea with convoy 3206.

Beginning at dawn, Vice Admiral (later Admiral) Marc A. Mitscher’s Task Force 58's five fleet carriers and four light carriers, supported by six battleships, ten cruisers and 28 destroyers, launch air attacks on airfields, shore installations and ships in the lagoon. Mitscher launches 30 strikes of at least 150 aircraft each. The strikes are launched about every hour.

40 miles NW of Truk. At about 1300, Rear Admiral (later Vice Admiral) Robert C. Giffen's (former CO of SAVANNAH, CL-42), Task Group 50. 9's NEW JERSEY (BB-62), IOWA (BB-61), MINNEAPOLIS (CA-36), NEW ORLEANS (CA-32), BRADFORD (DD-545) and BURNS (DD-588) are conducting an anti-shipping sweep around Truk to destroy enemy naval vessels escaping to the north. They sink light cruiser KATORI, destroyer MAIKAZE and auxiliary subchaser SHONAN MARU No. 15 with gunfire, but destroyer NOWAKI escapes after evading long- range 16-inch gun salvos from the battleships.

W of Truk. One of Task Group 50. 9 lookouts sights another small warship. Destroyer BURNS is detached to attack the vessel. BURNS overtakes CH-24. The subchaser opens fire and an uneven gunfire duel ensues. BURNS gets hits with her fast-firing 5-inch DP and 40-mm AA guns, but CH-24's sole 3-inch gun fails to score. At 1655, CH-24 sinks by the stern at 07-24N, 150-30E. From 50 to 75 survivors of CH-24's crew are seen in the water. Most refuse rescue, but BURNS rescues six who identify the subchaser.

In two days of raids, Task Force 58 sinks 31 transports and 10 naval vessels (two cruisers, four destroyers and four auxiliary vessels), destroys nearly 200 aircraft and damages severely about 100 more. Truk is eliminated as a major fleet anchorage for the IJN.

30 April 1944:
Removed from the Navy List.

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Authors' Notes:
[1] According to historian/author Kimata Jiro, CH-24 and CH-22 made several depth charge attacks, one of which may have been against TRITON. At about that time, FLORIDA MARU was torpedoed and taken in tow by TONEI MARU. If FLORIDA MARU's attacker was, indeed, TRITON, the submarine probably was CH-24 and CH-22's victim. Nevertheless, the identity of the subchasers' target has not been firmly established and TRITON's loss remains a mystery.

[2] Available records list HOSHI MARU No.7 as part of the convoy, but since she was not completed until 2 November in Japan, her inclusion seems unlikely. HOSHI MARU No. 5, however, was completed on 30 September, (later renamed KOMANDORI MARU) and was known to be in the area.

Thanks go to John Whitman of the USA for info on CNO intercepts of Japanese messages.

-Bob Hackett, Sander Kingsepp and Peter Cundall.

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