|Departure date||6 September 1944|
|No. of POWs||1,318 (One US, 600 Brit, 717 Aus)|
|Location of disaster||Off Hainan Island|
|Date of disaster||12 September 1944|
|Photo||Courtesy of NYK Maritime Museum|
HI-72 Convoy, consisting of seven vessels - Kachidoki Maru (flagship with the 16th Shipping Forces Commander aboard, the ashes of 582 war dead, the British POWs, and 6,000 tons of bauxite), Asaka Maru (593 passengers and bauxite), Shincho Maru (573 passengers and a load of fuel oil), Nankai Maru (6,500 tons of bauxite and 4,000 drums of av-gas), Zuiho Maru (8,000 tons of oil), Kimikawa Maru (273 passengers, bauxite and av-gas), and Rakuyo Maru (US, British and Australian POWs and bauxite) - was escorted by the Coast Defense Ships Hirado (flagship with the 6th Escort Fleet Commander aboard), Mikura, Kurahashi, No. 11, sub-chaser No. 19 and destroyer Shikinami, left Singapore on 6 September 1944. Among the POWs aboard Rakuyo Maru were Australian Brigadier Author Varley and USAAF Colonel Harry Melton. About 2,200 POWs aboard Kachidoki Maru and Rakuyo Maru had suffered the heat in the hot holds for 36 hours before their departure. The Australians did not put up with the crowded holds, and they openly broke into revolt. In order to prevent a bloodshed incident, the Japanese skipper allowed about 200 POWs to come up to the deck at a time.
At noon on 7 September, the convoy passed about 150 NM east of Kota Bharu, and changed course to northeast at the middle of the entrance to the Gulf of Siam, and headed for Japan. By noon on 8 September, they passed off the southern tip of French-Indochina (present Vietnam), and about 09:00 on 11 September, Kagu Maru, Gokoku Maru, and Kibitsu Maru of MAMO-03 from Manila joined HI-72 at about 120 NM east of Hainan, and entered under the command of the 6th Escort Fleet Commander. Then the three escorts CDV No. 10 and No. 20, and mine-sweeper No. 21 were relieved of their duty, and returned to Manila. The enlarged convoy was re-organized, and Rakuyo Maru moved to the rear of the starboard column.
About this time, in the waters around 18-00N, 114-00E called the "Convoy College," the USS Growler, Sealion II, and Pampanito were patrolling the area. Although each commanding officer of the submarine was informed via Ultra message that an important convoy would leave Singapore on 6 September and head for Japan by the Operations Officer of the ComSubPac (Commander Submarine Forces Pacific) in Pearl Harbor. However, the Operations Officer himself knew nothing whatsoever about POWs being transported on this convoy.
At 01:55 on 12 September, Hirado was suddenly torpedoed by Growler, and sank instantly. The convoy was plunged into chaos for a while, but soon resumed normal conditions. However, as the sun was just rising, the torpedoes Sea Lion fired struck Nankai Maru first. Then at 05:31, a second torpedo hit Rakuyo Maru's bow, and penetrated No. 1 hold filled with rubber. A third torpedo run directly into her engine room, and the main engine and auxiliary machines, such as generators were stopped, and she became unable to make way. If the torpedo had hit No. 2 hold, hundreds of POWs would have been killed. With the drainage pumps becoming inoperative, the ship gradually went down by taking on water. Shortly before 07:00, Growler came back for another attack, and the torpedoes she fired struck Shikinami. At 08:45, Nankai Maru disappeared beneath the waves.
Aboard Rakuyo Maru, the Japanese rushed to the lifeboats, kicking out POWs who tried to get into the boat with them. Many men jumped into the water. At 06:55 when Shikinami went down, the depth charges she had loaded exploded, causing shock waves, which resulted in internal injuries to those who were in the water. Confusion prevailed at the scene, and there were cases of murder on both sides. On Rakuyo Maru, as many Japanese abandoned the ship first, some POWs got revenge on their guards. About 10 POWs attacked the shipping artillery men at bow deck gun. A POW grabbed an iron bar, and walked toward the bridge, saying that he would kill some Japanese before going over the side. In the water, lone Japanese was beaten to death after the escort ships were gone. About 13 hours after she was torpedoed, at about 18:20, Rakuyo Maru disappeared beneath the waves in the east waters of Hainan (18-32N, 114-29E)
By 19:00 on 12 September, the Japanese escorts had picked up everyone they were going to rescue; about 1,200 British and Australian POWs were left in the water. As the escorts were leaving the scene, they passed right through the middle of the floating POWs; some were chopped up by the screws, and others were drowned.
Let's return to 07:00 in the morning. After Shikinami went down, Kagu Maru, Gokoku Maru, and Kibitsu Maru were thrown into disorder by the attacks of Growler and Sealion, and then headed for Hainan separately. After Kachidoki Maru, Asaka Maru, Shincho Maru, Zuiho Maru, and two escorts steamed to the north to dodge the enemy submarines and escape, and when they were about to change course toward Hainan, .this time, Zuiho Maru was hit by a torpedo Pampanito fired. At 22:50, she transmitted a distress message. Location was 19-23N, 111-50E. For Kachidoki Maru, the situations changed rapidly. She sighted three torpedo wakes coming on her port side, and avoided two by making a hard left turn, but one hit No. 7 hold, and split seams along the water line, which instantly caused flooding in other holds and engine room. The engine stopped, and at 23:15, the skipper ordered, "Abandon ship." Soon, Kachidoki Maru took a heavy list and slipped into the water at 2337. Although the loss of crewmember was only 12, 476 passengers and POWs were killed.
On the morning of September 13, Nissho Maru, Kasuga Maru, CDV No. 11 and sub-chaser No. 19 were dispatched from Hainan and rescued the survivors of Kachidoki Maru. The three vessels which had been relieved from MANO-03 escort were also ordered to rush to the waters where HI-72 had been attacked. Of the survivors of Rakuyo Maru, the Medical Officer, Captain Roland Richards was on one of a group of four boats, and another group of seven boats on which Brigadier Varley and Colonel Melton were drifting, remaining within the sight of each other. On the morning of 14 September, a Japanese CDV appeared, and to the great surprise of the survivors, this CDV No. 10 rescued 157 POWs of Dr. Richards' group. According to his statement, before they were rescued, they had heard gunfire. The survivors aboard those seven boats, including Brigadier Varley and Colonel Melton, were never seen or heard from again.
After attacking the convoy, Growler was detached from the wolf pack and returned to her base, and Sealion and Pampanito would patrol near Hainan for a few days. On the afternoon of 15 September, while steaming, Pampanito found wreckage and approached for investigation. They found that there were some men floating on rafts. They brought small arms out of the gun locker, and were ready to take prisoners. There was no set policy regarding the disposition of survivors of a sunken ship. It was entirely up to the skipper under such circumstances. He shouted, "Anyone who wants to shoot Japs, get yourselves a Tommy gun and come out on deck." Then, a whole bunch of guys came out on the deck with Tommy guns. As Pampanito approached several rafts with some 15 men on them, they saw some had Australian "Digger" hats on. They were waving and shouting as hard as they could.
"Who in the world are you?" Someone asked. "Prisoners of war. Australians and British POWs. Please help us!" But the skipper was not yet sure. He wanted to be extra cautious, and said, "Get the one speaks English!" The answer was indignant. "You bloody bastards. We all speak English!" Then the skipper ordered to pick them up, and rescue began.
Pampanito moved slowly in the wreckage, thoroughly searching for more survivors. She broke radio silence, called Sealion about 30 NM northeast, and asked for help. Sealion steamed down at flank speed, and began rescuing the survivors.
At 18:35, Pampanito radioed the ComSubPac in Pearl Harbor, and reported the situations, then continued the search until the night, and rescued 73 men (one died after rescued). Sealion also rescued 54 men (four died), and contacted the ComSubPac by radio, and was instructed to hurriedly steam to Saipan with Pampanito. The ComSubPac ordered Barb and Queenfish to immediately proceed to the scene of rescue, however, at a point about 150 NM more to go, they encountered HI-74, another convoy escorted by Escort carrier Unyo, which had left Singapore 5 days after HI-72. They launched attacks on this convoy, and sank Unyo and another ship. By so doing, they spent a few more precious hours to get to the scene of rescue.
On the afternoon of 17 September, Barb and Queenfish began their search and rescue. However, due to an approaching typhoon, it made the rescue extremely difficult. For all afternoon on the 17th into 18th, those two submarines thoroughly searched the area, and picked up a total of 32 survivors (two died). On the morning of 19 September, they discontinued the search and rescue, and headed for Saipan.
Although the Ultra did not disclose the cargoes of the ships to the submarine commanders, JICPOA (Joint Intelligence Center Pacific Ocean Area) knew. As early as 5 September, the names of the ships, cargoes, destination, and daily noontime positions of the convoy had been intercepted and decoded. (Death on the Hellships, Gregory Michno, p211)
Judging the situations from a wider standpoint, were 2,200 Allied POWs' lives worth less than several ships and av-gas, oil, and tons of bauxite ore they were carrying?
The story of Kachidoki Maru and Rakuyo Maru ends here. However, we will briefly describe what has become of those POWs who were on those two ships. The survivors of HI-72 were taken to Yulin, Hainan. There, the convoy was re-organized in two echelons; one consisting of Asaka Maru, Kagu Maru, Gokoku Maru, and Kibitsu Maru, escorted by five CDVs bound for Moji, and another consisting of Shincho Maru with one sub-chaser and auxiliary net-layer Kainan Maru as escorts bound for Takao. One hundred and fifty-seven POWs from Rakuyo Maru, 520 POWs from Kachidoki Maru, and about 1,000 survivors of HI-72 were put aboard Kibitsu Maru. They departed Yulin on the evening of 16 September. According to the original planning, the POWs were to travel on the open deck of a loaded tanker Shincho Maru. Under the circumstances, they would be helpless, if torpedoed. Many POWs had almost come to rebelling. Their strong protest worked, and on 15 September, they were transshipped to Kibitsu Maru.
The two convoy echelons were tossed about by the same typhoon which had disturbed search and rescue of the two US submarines. In the storm, they were separated. About 10:00 on 20 September, when the first echelon reached about 30 NM south of the Pescadores, they were attacked by B-24s from the Chinese Mainland, and almost all of them, except Kibitsu Maru, suffered damage. Then, she changed her planning, made a call at Keelung, Taiwan, and waited for the arrival of Kagu Maru, after repaired at the Pescadores. From Keelung, Kibitsu Maru and Kagu Maru organized a convoy, escorted by three CDVs, departed there at noon on 25 September, and headed for Moji. At midnight on 27 September, one of the CDVs was torpedoed by the USS Plaice and instantly sank. Kibitsu Maru and Kagu Maru sped off independently, and both of them arrived at Moji on the morning of 28 September, at about the same time.
Note 1: After the war, Medical Officer Richards became well known as industrial and sports physician in Australia. He wanted to express his gratitude to the skipper of the CDV and/or his family, who had stopped his ship exposing himself to danger of being torpedoed in the hostile waters infested by US submarines, and saved the lives of Dr. Richards and his comrades. At his request, this Network made researches and confirmed that the ship was CDV No. 10, and the name of the commanding officer was Lt. Commander Shiro Ichinose, a graduate of the Kobe Higher Mercantile Marine School. This Network asked the Yomiuri Shimbun to carry an article that we were searching for Mr. Ichinose on behalf of Dr. Richards. However, no clue was found. Dr. Richards is considering about establishing some sorts of a memorial stone for Mr. Ichinose.
Note 2: The exact limits of unrestricted warfare remained ambiguous for submariners throughout the war. Such a state of affairs (destroying small wooden fishing vessels, etc.) left individual submarine commanders as the arbiters of the limits of unrestricted warfare. p171, Execute against Japan by Joel Holwitt