Service history
November 1943–February 1944
Upon commissioning, I-43 was assigned to Submarine Squadron 11. [1] After she completed her work-ups, her 140-millimeter (5.5 in) deck gun was removed from her afterdeck and replaced by fittings that allowed her to carry a 46-foot (14 m) waterproofed Daihatsu-class landing craft abaft her conning tower. [1] On 15 November 1943, she was reassigned to Submarine Division 11 in the 6th Fleet along with the submarines I-42, I-45, I-52, I-183, I-184, Ro-40, Ro-41, Ro-43, Ro-113, Ro-114, and Ro-115. [1] In late November 1943, she took part in antisubmarine warfare exercises in the Iyo Nada in the Seto Inland Sea with I-42, I-184, Ro-40, Ro-113, and the submarine tender Chōgei. [2] She moved from Sasebo to Yokosuka during December 1943 [1] and from Yokosuka to Kure in January 1944. [1]
On 9 February 1944, I-43 got underway from Kure to perform a special mission in which she was to transport Special Naval Landing Forces (SNLF) personnel from Saipan in the Mariana Islands to Truk as part of a build-up of forces for a planned Japanese counterlanding on the Green Islands. [1] While at sea, she was reassigned to Submarine Division 15 in the 6th Fleet on 11 February 1944. [1] She arrived at Saipan on 13 February 1944 and embarked 59 SNLF personnel there. [1] On 14 February 1944, she received orders from the 6th Fleet to proceed to Truk, and she put to sea that day with an estimated date of arrival at Truk of 16 February 1944. [1]
Loss
On 15 February 1944, I-43 was 280 nautical miles (520 km; 320 mi) east-southeast of Guam when the United States Navy submarine USS Aspro — operating submerged in the area in support of the upcoming Operation Hailstone, a major U.S. Navy raid on Truk — detected her propeller noises at 11:06. [1] At 11:21, Aspro′s commanding officer sighted I-43 heading south-southeast on the surface, zigzagging and making 17 knots (31 km/h; 20 mph) on a heading of 155 degrees true. [1] He identified her as an "I-9-class" submarine, and noted the number "443" — probably the Japanese character for "I" followed by "43" — and a hinomaru flag painted on her conning tower, as well as a large structure abaft her conning tower — apparently her waterproof Daihatsu — which he thought might be a midget submarine. [1]
Out of position for a submerged attack, Aspro allowed I-43 to pass, surfaced at 12:07, and began a lengthy, radar-assisted maneuver known to American submariners as an "end-around" to get herself into a favorable firing position ahead of I-43. [1] Finally ahead of I-43 that evening, Aspro fired four Mark XIV-3A torpedoes at her at a range of 2,100 yards (1,900 m) at 22:23. [1] At 22:24, two of them hit I-43, which exploded and sank by the stern at 10°23′N150°23′E / 10.383°N 150.383°E / 10.383; 150.383 (I-43) . [1] Aspro′s crew heard several more explosions after I-43 sank, the last of them at 22:27. [1]
On 8 April 1944, the Imperial Japanese Navy declared I-43 to be presumed lost in the vicinity of Truk with the loss of all 166 men on board. [1] She was stricken from the Navy list on 30 April 1944. [1]
Ro-106 was an Imperial Japanese Navy Ro-100-class submarine. Completed and commissioned in December 1942, she served in World War II, operating in the Solomon Islands campaign, New Guinea campaign, and central Pacific Ocean. She was sunk in May 1944 during her eleventh war patrol.
Yamafuku Maru was an auxiliary transport ship of the Imperial Japanese Navy during World War II. She served primarily as a troop transport and cargo ship during the war.
Ro-68 was an Imperial Japanese Navy Type L submarine of the L4 subclass. First commissioned in 1925, she served in the waters of Japan prior to World War II. During World War II, she supported Japanese forces during the Battle of Wake Island and the invasion of Rabaul and took part in the Aleutian Islands campaign. She served as a training submarine from late 1942 to late 1944 before returning to a combat role in Japanese waters late in the war. She surrendered to the Allies in 1945 at the conclusion of the war and was scuttled in 1946.
Ro-63, originally named Submarine No. 84, was an Imperial Japanese Navy Type L submarine of the L4 subclass. First commissioned in 1924, she served in the waters of Japan prior to World War II. During World War II, she operated in the Central Pacific and took part in the Aleutian Islands campaign, then in late 1942 was relegated to a role as a training ship and tender for midget submarines. After the war ended in 1945, she surrendered to the Allies, who scuttled her in 1946.
I-16 was one of five Type C cruiser submarines of the C1 sub-class built for the Imperial Japanese Navy, Commissioned in 1940, she deployed a midget submarine for the attack on Pearl Harbor and for an attack on ships at Diego-Suarez in Madagascar, conducted an anti-shipping patrol in the Indian Ocean, and took part in the Guadalcanal campaign, New Guinea campaign, and Bougainville campaign before she was sunk in May 1944.
I-39 was an Imperial Japanese Navy B1 type submarine. Completed and commissioned in 1943, she served in World War II, operating in support of Japanese forces in the Battle of Tarawa before she was sunk in November 1943.
I-40 was an Imperial Japanese Navy Type B2 submarine. Completed and commissioned in 1943, she served in World War II and disappeared after departing for her first war patrol in November 1943.
I-32 was an Imperial Japanese Navy B1 type submarine. Completed and commissioned in 1942, she served in World War II, operating in the Pacific Ocean and Indian Ocean and supporting Japanese forces in the New Guinea campaign and the Guadalcanal campaign before she was sunk in March 1944.
I-42 was an Imperial Japanese Navy Type B2 submarine. Completed and commissioned in 1943, she served in World War II and was sunk during her first war patrol in March 1944.
I-368 was an Imperial Japanese Navy Type D1 transport submarine. Completed and commissioned in August 1944, she served in World War II and was converted into a kaiten suicide attack torpedo carrier in January 1945. She was sunk in February 1945 while operating during the Battle of Iwo Jima.
I-363 was an Imperial Japanese Navy Type D1 transport submarine. Completed and commissioned in July 1944, she served in World War II and conducted transport missions between Japan and outlying islands until she was converted into a kaiten suicide attack torpedo carrier. She survived the war, but sank after striking a mine in the weeks immediately following its conclusion.
I-366 was an Imperial Japanese Navy Type D1 transport submarine. Completed and commissioned in August 1944, she served in World War II and conducted transport missions between Japan and outlying islands until she was converted into a kaiten suicide attack torpedo carrier. She survived the war, surrendered to Allied forces in 1945, and was scuttled in 1946.
I-367 was an Imperial Japanese Navy Type D1 transport submarine. Completed and commissioned in August 1944, she served in World War II and conducted transport missions between Japan and outlying islands until she was converted into a kaiten suicide attack torpedo carrier. She survived the war, surrendered to Allied forces in 1945, and was scuttled in 1946.
Ro-41 was an Imperial Japanese Navy Kaichū type submarine of the K6 sub-class. Completed and commissioned in November 1943, she served in World War II and conducted six war patrols, sinking a destroyer escort USS Shelton (DE-407) on one of them, before she was sunk in March 1945.
Ro-43 was an Imperial Japanese Navy Kaichū type submarine of the K6 sub-class. Completed and commissioned in December 1943, she served in World War II and was sunk in February 1945 during her fifth war patrol.
Ro-104 was an Imperial Japanese Navy Ro-100-class submarine. Completed and commissioned in February 1943, she served in World War II, operating in the Aleutian Islands campaign, New Guinea campaign, and Solomon Islands campaign before she was sunk in May 1944 during her tenth war patrol.
Ro-105 was an Imperial Japanese Navy Ro-100-class submarine. Completed and commissioned in March 1943, she served in World War II, operating in the Aleutian Islands campaign, New Guinea campaign, and Solomon Islands campaign and in the vicinity of Truk, Rabaul, and the Admiralty Islands before she was sunk in May 1944 during her fourth war patrol.
Ro-108 was an Imperial Japanese Navy Ro-100-class submarine. Completed and commissioned in April 1943, she served in World War II, operating in the Solomon Islands campaign, the New Guinea campaign — during which she sank the United States Navy destroyer USS Henley (DD-391) — and off the Admiralty Islands. She was sunk in May 1944 during her fifth war patrol.
Ro-113 was an Imperial Japanese Navy Ro-100-class submarine. Completed and commissioned in October 1943, she served in World War II, operating off the Admiralty Islands, in the Indian Ocean — where she sank the last Allied ship torpedoed by a Japanese submarine during World War II — and off the Philippine Islands. She was sunk in February 1945.
Ro-116 was an Imperial Japanese Navy Ro-100-class submarine. Completed and commissioned in January 1944, she served in World War II and was sunk in May 1944 during her second war patrol.
Japan
