|Empire of Japan|
|Laid down:||11 October 1934|
|Launched:||20 July 1936|
|Completed:||5 December 1938|
|Fate:||Sunk off Okinawa, 31 March 1945|
|Class and type:||Junsen-class J3 Type submarine|
|Length:||358.5 ft 6 in (109.42 m)|
|Beam:||29 ft 8 in (9.04 m)|
|Draft:||17 ft 3 in (5.26 m)|
|Range:||14,000 nmi (26,000 km) at 16 knots (30 km/h; 18 mph)|
|Test depth:||100 m (330 ft)|
|Complement:||100 officers and men|
|Aircraft carried:||1 × Yokosuka E14Y seaplane|
The Japanese submarine I-8 was a World War II Junsen Type J-3 Imperial Japanese Navy submarine. The vessel, along with I-7, were the largest Japanese submarines to be completed before the outbreak of the Pacific War. It was based on the KD (Kaidai) type. Both submarines participated in the attack on Pearl Harbor, they also conducted patrol missions with Yokosuka E14Y seaplanes.
In 1943 I-8 completed a technology exchange mission by sailing to German occupied France and back to Japan. Under a new commander later in her career, the submarine's crew committed several war crimes in the latter period of the second world war.
The Yanagi missions took place under the Axis powers' Tripartite Pact to provide for an exchange of strategic materials and manufactured goods between Germany, Italy, and Japan. Initially, cargo ships made the exchanges, but when that was no longer possible, submarines were used. Only seven submarines attempted the trans-oceanic voyage: I-30 (April 1942), I-8 (June 1943), I-34 (October 1943), I-29 (November 1943), I-52 (March 1944) and the German submarines U-180 and U-511 (August 1943).
Commanded by Shinji Uchino, I-8 departed Kure harbor on 1 June 1943, accompanied by I-10 and the submarine tender Hie Maru. Their cargo included two of the famed Type 95 oxygen-propelled torpedoes, torpedo tubes, drawings of an automatic trim system and a new naval reconnaissance plane, the Yokosuka E14Y. A supplementary crew of 48 men, commanded by Sadatoshi Norita, was also packed into the submarine, intended to man the German submarine U-1224, a Type IXC/40 U-boat and bring her back to Japan for reverse engineering.
On 20 August, I-8 rendezvoused with the German submarine U-161, commanded by Captain Albrecht Achilles. Two German radio technicians were transferred to I-8, as well as an FuMB 1 "Metox" 600A radar detector, which was installed on I-8's bridge. As I-8 entered the Bay of Biscay on 29 August, the Luftwaffe sent Ju 88 aircraft of KG 40 to provide air cover, she arrived in Brest safely two days later.
The Japanese submarine was warmly welcomed. Parties and visits to Paris and Berlin were organized for the crew for over a month, and German news agencies announced that "now even Japanese submarines are operating in the Atlantic."
I-8 left Brest on 5 October, with a cargo of German equipment, such as: machine guns, bomb sights, a Daimler-Benz torpedo boat engine, marine chronometers, radars, sonar equipment, anti-aircraft gunsights, electric torpedoes, and penicillin. The submarine also transported Rear Admiral Yokoi, naval attaché to Berlin since 1940; Captain Hosoya, naval attaché to France since December 1939; three German officers and four radar and hydrophone technicians.
I-8 hit rough seas in the South Atlantic off the Cape of Good Hope, which delayed her arrival in Singapore. She radioed her position to Germany, but the message was intercepted by the Allies, prompting an attack by anti-submarine aircraft, which failed. I-8 arrived in Singapore on 5 December, and finally returned to Kure, Japan on 21 December, after a voyage of 30,000 nautical miles (56,000 km).
Despite her distinction as the only wartime submarine to make a successful round trip voyage between Japan and Germany, I-8 later gained infamy under a new crew and commander, Tatsunosuke Ariizumi, because of the crew's treatment of Allied prisoners of war.
On 26 March 1944, during a cruise into the Indian Ocean, I-8 torpedoed the 5,787-ton Dutch freighter SS Tjisalak. The submarine surfaced amid the debris field and after a brief exchange of gunfire with the ship's defensive armament, collected the survivors on the submarine's deck. Shortly after the freighter had sunk, the merchantman's crew and passengers, totalling 97, were tied in pairs of two and then attacked by Japanese sailors, during which they were slashed with swords and beaten with monkey wrenches and sledgehammers before being shot, then kicked into the water. Six men managed to survive and found a life raft. They were later rescued by the Liberty ship SS James O. Wilder.
Two months later, I-8 was involved in another atrocity when she struck the 7,176-ton American Liberty ship SS Jean Nicolet with two torpedoes. The 100 crewmen abandoned their burning ship and took to the life-rafts. Again, the survivors were gathered on the submarine's deck. The massacre took several hours, as they were made to walk one at a time past the conning tower, where they were murdered. When an aircraft approached, the submarine dived, plunging the remaining bound prisoners into the ocean, where most drowned. Sources differ, but it is believed 23 men made it to a life raft, from which they were picked up by the armed trawler HMS Hoxa 30 hours later. Five prisoners were taken to Japan by the submarine; one of them, Francis J. O'Gara, was found alive in a prison camp after the war. A new Liberty ship, SS Francis J. O'Gara, had been named after him, making O'Gara the only living person to have a Liberty ship named after him.
I-8 also sank many other merchant ships, often with a high or even total loss of life, suggesting that additional war crimes were committed. Commander Ariizumi, who had encouraged and participated in the murders, committed suicide after the Japanese surrender. Few of the crew had survived the war, but three were located and prosecuted. One was granted immunity in return for testifying against his former comrades and was then allowed to return to the United States. The others were convicted and served prison terms, which were commuted by the Japanese government in 1955.
Bridgland, Tony (2002). Waves of Hate. Pen & Sword. ISBN 0-85052-822-4.