© 2006-2017 Bob Hackett, Sander Kingsepp and Peter Cundall
5 October 1943:
Tokyo Bay. Laid down at Yokosuka Navy Yard.
15 January 1944:
Launched and numbered CD-12.
22 March 1944:
Completed and registered in the IJN. Attached to Kure Naval District. Assigned to Kure Guard Force.
21 April 1944:
At 1100 departs Yokosuka on trials.
22 April 1944:
Arrives back at Yokosuka.
28 April 1944:
At 0600, CD-12 departs Tokyo with kaibokan NOMI, CD-18, CD-22, minesweeper W-27 and submarine chasers CH-16 and CH-18 escorting "Higashi Matsu" Convoy No. 7 (outbound) consisting of TATSUHARU, MITAKESAN, ASAHISAN, OKINAWA, YAMATAMA, BINGO, MEIRYU, MOJI and MIHO MARUs bound for Saipan; ASAKA MARU and landing ships T.128 and T.150 for Palau; KOSHIN and BOKUYO (MUTSUYO) MARUs for Yap and TAITO MARU for Chichijima.
29 April 1944:
At 1230 W-27 is detached and returns to Nagaura.
E 5 May 1944:
CD-12, ASAKA MARU, landing ships T.128 and T.150 arrive at Palau.
18 May 1944:
At 0500, CD-12 departs Palau for Saipan with auxiliary minesweeper FUMI MARU No. 2, auxiliary SHOHO MARU and auxiliary subchasers CHa-62 and URUPPU MARU escorting the "Asaka Maru" convoy consisting of ASAKA,
JINZAN, TENRYUGAWA and BOKUYO MARUs.
21 May 1944:
At 0925, LtCdr Vernon C. Turner's (USNA ’33) USS BILLFISH (SS-286) torpedoes and damages BOKUYO MARU. TENRYUGAWA MARU takes BOKUYO MARU in tow covered by CD-12.
23 May 1944:
At 0012, URUPPU MARU joins CD-12 escorting the towing group. At daybreak, aerial cover is provided from Saipan.
24 May 1944:
The main body of the convoy arrives at Saipan.
27 May 1944:
At 2137, CD-12, URUPPU MARU and the towing group arrive at Saipan.
31 May 1944:
At 0600, CD-12 departs Saipan for Yokosuka with destroyer HATAKAZE, minelayer SARUSHIMA, minesweeper W-20, auxiliary minesweeper FUMI MARU No. 2 and auxiliary store ship TAKUNAN MARU escorting convoy No. 4530 consisting of HAKUSAN, JINZAN, EIKO, NATSUKAWA, SHUNSEN, KAIKO and CHIYO MARUs and UNYO
MARU No. 8.
2 June 1944:
250 miles W of Uracas Island. At 2207, CHIYO MARU is attacked by LtCdr Edward N. Blakely’s (USNA ’34) USS SHARK (SS-314) and hit by two torpedoes port side under the rear of the bridge. About ten minutes later, CHIYO MARU sinks at 21-00N 140-30E taking down 97 of her 143 passengers and five crewmen. CD-12 and the other escorts counter-attack and drop a total of 39 depth-charges, but without damage to USS SHARK.
4 June 1944:
317 miles WSW of Iwo-Jima. At 0405, HAKUSAN MARU is attacked by LtCdr John D. Crowley’s (USNA ’34) USS FLIER (SS-250) and hit port side by two of three torpedoes he fires. At 0415, HAKUSAN MARU’s stern rises
vertically and she sinks at 22-37N 136-50E. 23 crewmen, nine gunners, 16 of 71 troops and 277 of 375 passengers (mostly women and children) are KIA. CD-12 and the other escorts counter-attack and drop 34 depth-charges, but without damage to USS FLIER.
8 June 1944:
At 0800, the remainder of the convoy arrives at Yokosuka.
25 June 1944:
5 July 1944:
Arrives back at Nagaura.
10 July 1944:
At 0500, CD-12 departs Nagaura near Yokosuka for Iwo-Jima and Chichi-Jima with destroyers WAKABA and HATSUHARU, kaibokan AMAKUSA, minesweeper W-27 and auxiliary subchaser FUMI MARU escorting convoy No. 3710 consisting of NISSHU, TAISEI, TONEGAWA, DAIJI and EIKO MARUs and TOKAI MARU No. 4.
12 July 1944:
At 1500, CD-12 and AMAKUSA are detached with NISSHU, TAISEI and TONEGAWA MARUs and head for Iwo Jima.
14 July 1944:
Arrives at Iwo-Jima. The merchant ships unload and depart.
15 July 1944:
Arrives at Chichi-Jima.
16 July 1944:
CD-12 departs Chichi Jima with destroyer WAKABA and HATSUHARU and kaibokan AMAKUSA and minesweeper W-27 escorting convoy No. 3716 consisting of TAISEI, TONEGAWA and EIKO MARUs.
19 July 1944:
At 1025, convoy No. 3716 arrives at Yokosuka.
29 July 1944:
Subchasers CH-52 and CH-51 depart Tateyama for Chichi-jima with destroyer escort MATSU, flagship of the 2nd Convoy Escort Group's Commander Rear Admiral Takahashi Ichimatsu (40)(former CO of TSUGARU), destroyer HATAKAZE, kaibokan CD-4 and Navy transports/landing ships T-2 and T-4 escorting convoy No. 3729 consisting of SHOGEN, TONEGAWA, ENJU, KYUSHU and HOKKAI MARUs and UNKAI MARU No.7.
That same day, light carrier ZUIHO, escorted by destroyer FUYUTSUKI, sorties from Yokosuka to provide air and anti-submarine cover for the convoy.
1 August 1944:
Convoy No. 3729 arrives at Futami Harbor, Chichi-jima. Upon arrival, some of the cargo ships depart for Iwo Jima. Bad weather causes delays in unloading. ZUIHO and FUYUTSUKI, after maintaining position near the lzu Shichi Islands, make for the West Inland Sea..
4 August 1944:
About 0930, an air raid warning is received from Tokyo. All ships proceed to sea in convoy No. 4804. From 1030 on, the convoy is attacked by three waves of aircraft of Rear Admiral (later Admiral) Joseph J. Clark's (USNA ’17) (former CO of USS YORKTOWN, CV-10) Task Group 58.1. The first wave attacks the convoy 20 miles NW of Chichi-Jima. Destroyer HATAKAZE suffers rudder damage. At about 1100, kaibokan CD-4 is near-missed by bombs fore and aft to starboard. She suffers slight damage with two men KIA. The Japanese claim shooting-down several aircraft.
In the second raid, ENJU MARU is sunk with the loss of 52 crewmen and 21 passengers. The third strike occurs between 1600 and 1630, during which the majority of the ships succumb to torpedo attacks from both sides of the convoy. CD-12 incurs some damage. After organizing the rescue of the convoy’s survivors, flagship MATSU leads the still intact escort group and TONEGAWA MARU, the lone surviving cargo ship, northwards.
At 1254, Rear Admiral (later Admiral) Laurance T. DuBose's Task Unit 58.1.6 consisting of CruDiv 13’s USS SANTA FE (F) (CL-60), USS MOBILE (CL-63), USS BILOXI (CL-80) and USS OAKLAND (CL-95), DesDiv 100’s USS COGSWELL (DD-651), USS INGERSOLL (DD-652) and USS KNAPP (DD-653) and DesDiv 91’s USS IZARD (DD-589), USS CHARRETTE (DD-581), USS BURNS (DD-588) and USS BROWN (DD-546) is detached to sink the cripples.
At 1800, CD-4 sights DuBose's warships closing from the south. Rear Admiral Takahashi Ichimatsu (40) orders CD-4 to protect TONEGAWA MARU and continue fleeing while his flagship MATSU attempts to draw off the Americans. At 1930, MATSU is taken under fire and sunk by shell fire of USS COGSWELL, USS INGERSOLL and USS KNAPP at 27-40N, 141-48E. Rear Admiral Takahashi is KIA as are all but six of MATSU's crew. He is promoted Vice Admiral, posthumously.
Later, the Americans overtake and sink TONEGAWA MARU with 83 crewmen and 61 troops KIA. CD-4, CD-12, HATAKAZE and subchaser CH-51 escape.
5 August 1944:
Arrives at Yokosuka.
15 August 1944:
Departs Yokosuka with light cruiser YASOJIMA and IOSHIMA, auxiliary minesweeper TOSHI MARU No. 8, Naval transport landing ship T-134 and kaibokan CD-4 in convoy No.3815, consisting of SHORYU MARU and HIYOSHI MARU No. 2 GO. The warships are carrying supply drums with ammunition and food for the garrison of Iwo Jima. The merchant ships only proceed as far as Haha-Jima.The convoy arrives at Tateyama and anchors there.
17 August 1944:
21 August 1944:
Arrives at Haha Jima.
23 August 1944:
Departs Haha Jima.
25 August 1944:
After sundown, the escorts and T-134 arrive off the coast of Iwo Jima. After establishing the contact with shore units, the drums are released offshore.
29 August 1944:
CD-12 returns to Yokosuka.
6 September 1944:
CD-12 departs Yokosuka for Haha-Jima with light cruiser YASOJIMA (ex-Chinese P'ING HAI) and kaibokan CD-4 and auxiliary subchaser FUMI MARU escorting convoy No. 3905 consisting of SHORYU and TOKIWASAN MARUs.
E 7 September 1944:
Arrives at Tateyama.
9 September 1944:
At 1520, the convoy departs Tateyama. At about 1600, shortly after the ships leave port, LtCdr Anton R. Gallaher's (USNA ’33) USS BANG (SS-385) torpedoes and sinks both TOKIWASAN MARU carrying the 1st Shinyo Air Base Group and taking down nine crewmen and 14 passengers, and SHORYU MARU with the loss of four of her crew and 64 passengers, at 28-58N, 137-45E.
11 September 1944:
The escorts arrive at Chichi-Jima.
12 September 1944:
14 September 1944:
Arrives at Nagaura and undergoes repairs.
23 September 1944:
CD-12 departs Yokohama with submarine chasers CH-44 and CH-51 escorting convoy No. 3923 consisting of IKUTAGAWA, SHIBAZONO MARUs and Oil Tanker No. 3998 bound for Chichi-Jima. En route IKUTAGAWA MARU is detached at Hachijo Jima. The convoy anchors at Tateyama.
30 September 1944:
Arrives at Chichi-Jima early that day. At 2200 CD-12 departs Chichi-Jima with submarine chasers CH-44 and CH-51 escorting convoy No. 4930 consisting of SHIBAZONO MARU and Oil Tanker No. 3998 bound for Yokosuka.
4 October 1944:
At 1630 arrives at Yokosuka.
20 October 1944:
Repairs are completed.
24 October 1944:
CD-12 and submarine chaser CH-42 depart Yokohama escorting convoy No. 3024 consisting of JUZAN MARU I GO and RYUJIN MARU. The ships later arrive at Tateyama.
25 October 1944:
29 October 1944:
Arrives at Haha Jima. RYUJIN MARU is joined by auxiliary minesweeper KEINAN MARU and proceeds to Chichi-Jima. The rest of the convoy remains at Haha-Jima.
30 October 1944:
CD-12 and submarine chaser CH-42 depart Haha Jima escorting convoy No. 4030 consisting of JUZAN MARU I GO bound for Yokosuka.
3 November 1944:
Arrives at Shimoda.
4 November 1944:
Departs Shimoda and later that day arrives at Nagaura.
7 November 1944:
Transfers from Nagaura to Yokosuka.
16 November 1944:
25 November 1944:
Arrives back at Yokosuka.
12 December 1944:
At 1415, CD-12 departs Tateyama for Chichi-Jima with CD-6, minesweeper W-29 and subchaser CH-42 escorting convoy No. 3209 consisting of JUZAN, YAEI, KAIKO and SHOTO MARUs.
13 December 1944:
The convoy encounters bad weather and at 1136 puts into Hachijo-Jima. At 1653, the same day, it departs.
16 December 1944:
At 0229, LtCdr Robert R. Williams Jr’s (USNA ’34) USS FINBACK (SS-230) torpedoes and sinks JUZAN MARU at 27-24N, 141-44E. 33 crewmen are KIA. Williams fires several torpedoes at W-29 and CH-42, but misses. There is no counter-attack. Later that day, the convoy arrives at Chichi-Jima and unloads.
17 December 1944:
The convoy, now numbered No. 4217, departs Chichi-Jima.
22 December 1944:
At 0314, the convoy arrives at Tateyama.
27 December 1944:
CD-12 departs Tateyama with submarine chaser CH-42 and minesweeper W-29 in convoy No. 3226 consisting of YAEI, SHIBAZONO, YONEYAMA MARUs and NANYO MARU No. 1.
31 December 1944:
Arrives at Chichi-Jima.
1 January 1945:
At 1700, CD-12 departs Chichi-Jima for Tateyama with minesweeper W-29 and subchaser CH-42 escorting convoy No. 4101 consisting of SHIBAZONO, YONEYAMA, YAEI MARUs and NANYO MARU No.1.
3 January 1945:
At 2030, LtCdr Talbot E. Harper’s (USNA ’37) USS KINGFISH (SS-234) torpedoes and sinks SHIBAZONO MARU at 30-21N, 142-15E. 57 crewmen are KIA. Harper also torpedoes and sinks small freighter YAEI MARU. 27 crewmen, two gunners and two passengers are KIA. CD-12 and subchaser CH-42 counterattack, but their attack is not recorded by USS KINGFISH.
6 January 1945:
At 0918, the convoy arrives at Tateyama. Late that day transfers from Tateyama to Yokosuka.
15 January 1945:
Departs Yokosuka and later that day arrives at Tateyama.
16 January 1945:
At 1200, CD-12 departs Tateyama for Chichi-Jima with kaibokan CD-56, subchasers CH-42, CH-47 and minesweeper W-29 escorting convoy No. 3115 consisting of KURETAKE, YONEYAMA MARUs and NANYO MARU No. 1 and UNYO MARU No. 6.
19 January 1945:
At 1046, the convoy is attacked by a group of large American aircraft, but the attack is beaten off. Arrives at Futami, Chichi-Jima.
20 January 1945:
At 0013, CD-12 departs Chichi-Jima for Tateyama with kaibokan CD-56, and minesweeper W-29 escorting convoy No. 4119 consisting of KURETAKE MARU and NANYO MARU No. 1.
23 January 1945:
At 0100, the convoy arrives at Tateyama. Later that day the convoy arrives at Tokyo Bay and the escorts detach at Yokosuka.
30 January 1945:
Transfers from Yokosuka to Yokohama.
31 January 1945:
Departs Yokohama with minesweeper W-29 for Chichi-Jima escorting convoy No. 3131 consisting of RYUJIN MARU and one unidentified ship ending in San/Yama. Later that day arrives at Tateyama.
1 February 1945:
At 0300 departs Tateyama with auxiliary submarine chaser TAKUNAN MARU No. 2 as an additional escort.
4 February 1945:
At 0740 arrives at Chichi Jima.
7 March 1945:
At 1100 arrives at Yokosuka.
11 March 1945:
At 0900 departs Yokosuka.
14 March 1945:
At 1700 arrives at Moji.
18 March 1945:
At 1100 departs Moji.
19 March 1945:
Transferred to AS-3 anti submarine unit.
Early April 1945:
CD-12 arrives in Miyazu Bay, Sea of Japan. She serves as a provisional target for the aircraft from the Mineyama Detachment of Himeji NAG.
20 April 1945:
During a low-level training flight a Yokosuka K5Y1 Type 93 Intermediate Trainer grazes the mast of CD-12, riding at anchor. The aircraft crashes, killing both pilots.
14 May 1945:
CD-12 returns to Miyazu Bay after repairs at Maizuru.
27 May 1945:
Korea Strait, off Geomundo Island. Kaibokan AGUNI and OKINAWA are attacked by two Consolidated PB4Y-2B "Privateers"of Patrol Bombing Squadron VPB-109. Lt Leo E. Kennedy launches a radar-guided “Bat” glide bomb. The bomb's 1,000-lb warhead explodes off AGUNI’s starboard bow demolishing the whole foredeck area. CD-12 is dispatched to assist in rescuing AGUNI’s crew, but despite the heavy damage AGUNI remains navigable and proceeds stern first to Pusan, Korea.
15 August 1945:
At Maizuru CD-12’s crew receives notification of the termination of war.
30 November 1945:
Removed from the Navy List.
1 December 1945:
Assigned to minesweeping duties by the Allied Occupation Forces. 
5 September 1947:
Ceded to the United States as a war reparation.
10 September 1947:
Sasebo. Start of scrapping.
30 November 1947:
End of scrapping.
 USS FLIER, while transiting the Balabac Strait, Philippines, on 13 August 1944 struck a mine and sank. Fourteen of 86 crewmen escaped, but only eight survived the long swim in the Sulu Sea to shore. After making their way by raft to Palawan, at the end of the month they were evacuated by USS REDFIN (SS-272). In the spring of 2009, a dive team from YAP Films located the wreckage of the submarine at a depth of 330 feet. On 1 February 2010, the USN confirmed that the submarine is FLIER.
 In 1945, the U. S. Army Air Force launched a five-phased campaign known as “Operation Starvation” to mine Japan’s home waters. The USAAF used 80 to 100 B-29 “Superfortress” heavy bombers of the 21st Bomber Command based at Tinian in the Marianas. The B-29s could carry seven 2,000 lb. or twelve 1,000 lb. mines.
Beginning on 27 March 1945 and continuing until 5 August 1945, the B-29s flew 1,529 nighttime radar sorties and laid 4,900 magnetic, 3,500 acoustic, 2,900 pressure and 700 low-frequency mines for a total of more than 12,000 mines laid in Japanese waters. These mines sank 294 ships, damaged 137 beyond repair and damaged another 239 that could be repaired. The total was 1, 250,000 tons sunk or damaged or about 75 percent of Japanese shipping available in March 1945. Only 15 B-29s were lost during the mining campaign.
Postwar, removal of these mines posed a major challenge for the Allied Occupation Forces. They pressed 269 Japanese ships of various types into minesweeping service to augment their own efforts.
Thanks for assistance to Mr. Gilbert Casse of France
-Bob Hackett, Sander Kingsepp and Peter Cundall