The was a class of submarine in the Imperial Japanese Navy (IJN) which served during World War II

World War II

World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...

. The Type-B submarines were similar to the Type-A apart from not having the headquarters installation.

Class variants

The Type-B submarines were divided into four classes:, the I-15 class, the I-40 class, the I-54 class. The 5115th vessel class submarines were not built and remained a design only.

Type-B (I-15 class)

Project number S37. Twenty boats were built between 1937 and 1944 under the Maru 3 Programme

3rd Naval Armaments Supplement Programme (Japan, 1937)

The otherwise known as the "Circle Three" Plan was the third of four expansion plans of the Imperial Japanese Navy between 1930 and the start of World War II.-Background:...

 (Boats 37 - 42) and Maru 4 Programme

4th Naval Armaments Supplement Programme (Japan, 1939)

The was one of the armaments expansion plan of the Imperial Japanese Navy .-Background:In 1939, the IJN started new naval armaments expansion plan...

 (Boats 139 - 152).

• Boats in class

  Boat No.	Boat	Builder	Laid down	Launched	Completed	Results	Fate
  37	I-15 Japanese submarine I-15 I-15 was a Japanese B1 type submarine. She was completed at Kure Navy Yard on September 30, 1940, whereupon she entered into service with the Imperial Japanese Navy. Her first and only commanding officer was Commander Nobuo Ishikawa. I-15 operated off the north coast of Oahu during the raid on...	Kure Naval Arsenal Kure Naval Arsenal was one of four principal naval shipyards owned and operated by the Imperial Japanese Navy. -History:The Kure Naval District was established at Kure, Hiroshima in 1889, as the second of the naval districts responsible for the defense of the Japanese home islands along with the establishment of the...	25-01-1938	07-03-1939	30-09-1940		Probably lost in an accident or sunk by enemy attack near Guadalcanal Guadalcanal Guadalcanal is a tropical island in the South-Western Pacific. The largest island in the Solomons, it was discovered by the Spanish expedition of Alvaro de Mendaña in 1568... , after 03-11-1942
  38	I-17 Japanese submarine I-17 I-17 was a Japanese B1 type submarine of the Imperial Japanese Navy which saw service during World War II. She was the first Axis ship to shell the United States mainland.-Pearl Harbor:...	Yokosuka Naval Arsenal Yokosuka Naval Arsenal was one of four principal naval shipyards owned and operated by the Imperial Japanese Navy, and was located at Yokosuka city, Kanagawa prefecture on Tokyo Bay, south of Yokohama...	25-08-1937	12-11-1938	31-01-1941	Sank SS Samoa on 18-12-1941 Sank on 21-12-1941 Damaged SS Larry Doheny on 23-12-1941 Sank Panamanian merchant ship Stanvac Manila on 23-05-1943	Sunk by HMNZS Tui HMNZS Tui (T234) HMNZS Tui was a Bird class minesweeper of the Royal New Zealand Navy. She was commissioned in 1941 for minesweeping and anti-submarine roles....  and maritime patrol aircraft at Nouméa Nouméa Nouméa is the capital city of the French territory of New Caledonia. It is situated on a peninsula in the south of New Caledonia's main island, Grande Terre, and is home to the majority of the island's European, Polynesian , Indonesian, and Vietnamese populations, as well as many Melanesians,...  23°26′S 166°54′E on 19-08-1943
  39	I-19	Mitsubishi, Kōbe Shipyard	15-03-1938	16-09-1939	28-04-1941	Sank SS H. M. Storey on 22-12-1941 Damaged SS Absoroka on 25-12-1941 Sank USS Wasp USS Wasp (CV-7) USS Wasp was a United States Navy aircraft carrier. The eighth Navy ship of that name, she was the sole ship of her class. Built to use up the remaining tonnage allowed to the U.S. for aircraft carriers under the treaties of the time, she was built on a reduced-size version of the Yorktown-class...  on 15-09-1942 Damaged USS North Carolina USS North Carolina (BB-55) USS North Carolina was the lead ship of her class of battleship and the fourth in the United States Navy to be named in honor of this U.S. state. She was the first new-construction U.S. battleship to enter service during World War II, participating in every major naval offensive in the Pacific...  on 15-09-1942 Damaged USS O'Brien USS O'Brien (DD-415) USS O'Brien was a World War II-era Sims-class destroyer in the service of the United States Navy, named in honor of Captain Jeremiah O'Brien and his five brothers, Gideon, John, William, Dennis and Joseph, who captured the HMS Margaretta on 12 June 1775 during the American revolution.The O’Brien...  on 15-09-1942 Sank SS Phoebe A. Hearst on 30-04-1943 Damaged on 02-05-1943 Sank SS William K. Vanderbilt on 16-05-1943 Sank SS M. H. DeYoung on 14-08-1943	Sunk by USS Radford USS Radford (DD-446) USS Radford , named for Rear Admiral William Radford, was a Fletcher-class destroyer in the United States Navy during World War II, the Korean War and the Vietnam War....  in the Gilbert Islands Gilbert Islands The Gilbert Islands are a chain of sixteen atolls and coral islands in the Pacific Ocean. They are the main part of Republic of Kiribati and include Tarawa, the site of the country's capital and residence of almost half of the population.-Geography:The atolls and islands of the Gilbert Islands...  on 25-11-1943
  40	I-21 Japanese submarine I-21 was a Japanese Type B1 submarine which saw service during World War II in the Imperial Japanese Navy. She displaced 1,950 tons and had a speed of . I-21 was the most successful Japanese submarine to operate in Australian waters, participating in the attack on Sydney Harbour in 1942 and sinking...	Kawasaki, Kōbe Shipyard	07-01-1939	24-02-1940	15-07-1941	Damaged SS Montebello on 23-12-1941 Damaged SS Idaho on 23-12-1941 Sank SS John Adams on 05-05-1942 Sank Greek merchant vessel Chloe on 04-05-1942 Sank Panamanian merchantman Guatemala on 11-06-1942 Sank USS Porter USS Porter (DD-356) USS Porter was the lead ship in her class of destroyers in the United States Navy. She was the third Navy ship named for Commodore David Porter and his son, Admiral David Dixon Porter....  on 26-10-1942 Damaged SS Edgar Allan Poe on 08-11-1942 Sank Australian merchant ship Kalingo on 17-01-1943 Sank SS Peter H. Burnett on 22-01-1943 Sank RMS Iron Knight on 08-02-1943 Sank SS Star King on 10-02-1943 Sank SS Cape San Juan on 21-11-1943	Probably lost in an accident or sunk by enemy attack near Tarawa, after 27-11-1943
  41	I-23	Yokosuka Naval Arsenal	08-12-1938	24-11-1939	27-09-1941	Damaged SS Agwiworld on 21-12-1941 Damaged SS Dorothy Philips on 24-12-1941	Probably lost in an accident or sunk by enemy attack near the Hawaiian Islands Hawaiian Islands The Hawaiian Islands are an archipelago of eight major islands, several atolls, numerous smaller islets, and undersea seamounts in the North Pacific Ocean, extending some 1,500 miles from the island of Hawaii in the south to northernmost Kure Atoll... , after 14-02-1942
  42	I-25 Japanese submarine I-25 was a B1-Type submarine of the Imperial Japanese Navy that served in World War II, took part in the Attack on Pearl Harbor, and carried out the only aerial bombing on the continental United States during wartime; during the so-called Lookout Air Raid; and the Bombardment of Fort Stevens, both...	Mitsubishi, Kōbe Shipyard	03-02-1939	08-06-1940	15-10-1941	Sank USS Emidio on 20-12-1941 Damaged SS Absaroka on 24-12-1941 Damaged SS Connecticut on 27-12-1941 Sank RMS Fort Camosun on 21-06-1942 Sank Camden on 04-10-1942 Sank Larry Doheny on 07-10-1942 Sank Soviet submarine L16 on 12-10-1942 Sank SS H. M. Storey on 18-05-1943	Probably lost in an accident or sunk by enemy attack near Espiritu Santo Espiritu Santo Espiritu Santo is the largest island in the nation of Vanuatu, with an area of . It belongs to the archipelago of the New Hebrides in the Pacific region of Melanesia. It is in the Sanma Province of Vanuatu.... , after 23-08-1943
  43							The dummy for the naval budget of the Yamato class battleships Yamato class battleship The were battleships of the Imperial Japanese Navy constructed and operated during World War II. Displacing at full load, the vessels were the heaviest and most powerfully armed battleships ever constructed. The class carried the largest naval artillery ever fitted to a warship, nine naval... .
  139	I-26 Japanese submarine I-26 I-26 was a Japanese B1 type submarine which saw service in the Imperial Japanese Navy during World War II. She was completed and commissioned at the Kure Dockyard on 6 November 1941, under the command of Commander Yokota Minoru....	Kure Naval Arsenal	07-06-1939	10-04-1940	06-11-1941	Sank USS Cynthia Olson on 08-12-1941 Sank SS Coast Trader on 08-06-1942 Damaged USS Saratoga USS Saratoga (CV-3) USS Saratoga was the second aircraft carrier of the United States Navy and the fifth ship to bear her name. She was commissioned one month earlier than her sister and class leader, , which is the third actually commissioned after and Saratoga...  on 31-08-1942 Sank USS Juneau USS Juneau (CL-52) The first USS Juneau was a United States Navy Atlanta-class light cruiser sunk at the Naval Battle of Guadalcanal in November 1942. In total 687 men, including the five Sullivan brothers, were killed in action as a result of its sinking....  on 13-11-1942 Sank Yugoslav merchant ship Recina on 11-04-1943 Sank Australian merchant vessel Kowarra on 24-04-1943 Damaged SS General Robert F. Hoke on 28-12-1943 Sank RMS Tornus on 31-12-1943 Sank SS Albert Gallatin on 01-01-1944 Sank SS H. D. Collier on 13-03-1944 Sank Norwegian merchant ship Grena on 21-03-1944 Damaged USS Santee USS Santee (CVE-29) The second USS Santee was launched on 4 March 1939 as Esso Seakay under a Maritime Commission contract by the Sun Shipbuilding and Dry Dock Company at Chester, Pennsylvania, sponsored by Mrs...  on 25-10-1944 (probably wrong since she was sunk the day before) Sank SS Richard Hovey on 29-03-1944	Probably lost in an accident or sunk by enemy attack east of the Philippines Philippines The Philippines , officially known as the Republic of the Philippines , is a country in Southeast Asia in the western Pacific Ocean. To its north across the Luzon Strait lies Taiwan. West across the South China Sea sits Vietnam... , after 27-10-1944
  140	I-27 Japanese submarine I-27 I-27 was a submarine of the Imperial Japanese Navy which saw service during the Pacific Campaign of World War II. I-27 was commissioned at Sasebo, Japan on February 24, 1942. The sub's commander, Commander Fukumura, had a history of machine-gunning survivors of ships she had sunk, including the...	Sasebo Naval Arsenal Sasebo Naval Arsenal was one of four principal naval shipyards owned and operated by the Imperial Japanese Navy. -History:The Sasebo Naval District was established at Sasebo, Nagasaki in 1886, as the third of the naval districts responsible for the defense of the Japanese home islands. After the establishment of the...	05-07-1939	06-06-1940	24-02-1942	Sank Australian merchant ship Iron Crown on 04-05-1942 Sank RMS Ocean Vintage on 10-22-1942 Sank RMS Fort Mumford on 21-03-1943 Sank Dutch merchantman Berakit on 07-05-1943 Sank SS Montanan on 03-06-1943 Sank RMS British Venture on 24-06-1943 Sank Norwegian merchant ship Dah Pu on 28-06-1943 Sank SS Alcoa Prospector on 05-07-1943 Damaged SS Lyman Stewart on 07-09-1943 Sank RMS Larchbank on 10-09-1943 Sank RMS Sambo on 10-11-1943 Sank RMS Sambridge on 18-11-1943 Sank Greek merchant ship Athina Livanos on 29-11-1943 Sank Greek merchant vessel Nitsa on 02-12-1943 Damaged RMS Fort Camosun on 03-12-1943 Sank HMS Khedive Ismail on 12-02-1944	Sunk by HMS Paladin HMS Paladin (G69) HMS Paladin was a P-class destroyer of the British Royal Navy that saw service during the Second World War. She was built by John Brown and Co. Ltd., Clydebank...  and HMS Petard HMS Petard (G56) HMS Petard was a "P"-class destroyer of the British Royal Navy that saw service during World War II. She was one of the three "P" class ships, out of the original eight, to survive the war in a serviceable condition....  in the Maldives Maldives The Maldives , , officially Republic of Maldives , also referred to as the Maldive Islands, is an island nation in the Indian Ocean formed by a double chain of twenty-six atolls oriented north-south off India's Lakshadweep islands, between Minicoy Island and...  at 00°57′N 72°16′E on 12-02-1944
  141	I-28 Japanese submarine I-28 I-28 was a submarine of the Imperial Japanese Navy which saw service during the Pacific Campaign of World War II. I-28 was commissioned at Kobe, Japan on February 6, 1942. The submarine participated in the Battle of the Coral Sea in May 1942...	Mitsubishi, Kōbe Shipyard	25-09-1939	17-12-1940	06-02-1942		Sunk by USS Tautog USS Tautog (SS-199) ', a Tambor-class submarine, was the first ship of the United States Navy to be named for the tautog, a small edible sport fish, which is also called a blackfish....  north of Rabaul Rabaul Rabaul is a township in East New Britain province, Papua New Guinea. The town was the provincial capital and most important settlement in the province until it was destroyed in 1994 by falling ash of a volcanic eruption. During the eruption, ash was sent thousands of metres into the air and the...  at 06°30′N 152°00′E on 17-05-1942
  142	I-29 Japanese submarine I-29 I-29, code-named Matsu , was a B1 type submarine of the Imperial Japanese Navy used during World War II on two secret missions with Germany, during one of which she was sunk.-Type B Submarines:...	Yokosuka Naval Arsenal	20-09-1939	29-09-1940	27-02-1942	Sank RMS Gazcon on 02-09-1942 Damaged RMS British Genius on 03-09-1942 Sank RMS Haresfield on 10-09-1942 Sank RMS Ocean Honour on 16-09-1942 Sank USS Paul Luckenbach on 23-09-1942 Sank RMS Tilawa on 23-11-1942 Sank Norwegian merchant ship Belita on 03-12-1942 Sank RMS Rahmani on 12-07-1943	Sunk by USS Sawfish USS Sawfish (SS-276) USS Sawfish , a Gato-class submarine, was a ship of the United States Navy named for the sawfish, a viviparous ray which has a long flat snout with a row of toothlike structures along each edge...  south of Sabtang Island Sabtang Island Sabtang is an inactive volcanic island, one of the Batanes Islands of the Philippines. Together with some other islands it forms the municipality of Sabtang in Batanes Province.-External links:*...   at 20°10′N 121°50′E on 26-07-1944
  143	I-30 Japanese submarine I-30 I-30 was a Type B1 submarine of the Imperial Japanese Navy during World War II. After operating in the Indian Ocean she participated in a Yanagi mission, aimed at connecting Japan and Nazi Germany by submarine. She was the first Japanese submarine to reach Europe, arriving at Lorient, France in...	Kure Naval Arsenal	07-06-1939	17-09-1940	28-02-1942		Sunk by a mine at Singapore Singapore Singapore , officially the Republic of Singapore, is a Southeast Asian city-state off the southern tip of the Malay Peninsula, north of the equator. An island country made up of 63 islands, it is separated from Malaysia by the Straits of Johor to its north and from Indonesia's Riau Islands by the...  on 13-10-1942
  144	I-31 Japanese submarine I-31 I-31 was a Type B1 submarine operated during World War II. She was sunk by American destroyers near Attu.-References:...	Yokosuka Naval Arsenal	06-12-1939	13-03-1941	30-05-1942		Sunk by USS Farragut USS Farragut (DD-348) The third USS Farragut , named for Admiral David Glasgow Farragut USN , was the lead ship of her class of destroyers in the United States Navy.-History:...  and USS Edwards USS Edwards (DD-619) USS Edwards was a Gleaves-class destroyer of the United States Navy. She was the second Navy ship named "Edwards", and the first named for Lieutenant Commander Walter A. Edwards , who as commander of in 1922 rescued nearly five hundred people from the burning French transport Vinh-Long. For his...  at Attu Island Attu Island Attu is the westernmost and largest island in the Near Islands group of the Aleutian Islands of Alaska, making it the westernmost point of land relative to Alaska and the United States. It was the site of the only World War II land battle fought on the incorporated territory of the United States ,...  on 14-05-1943
  145	I-32	Sasebo Naval Arsenal	20-01-1940	17-12-1940	26-04-1942		Sunk by USS Manlove USS Manlove (DE-36) USS Manlove was an of the United States Navy during World War II. She was promptly sent off into the Pacific Ocean to protect convoys and other ships from Japanese submarines and fighter aircraft...  and USS PT-1135 northeast of Wotje Atoll Wotje Atoll Wotje Atoll is a coral atoll of 75 islands in the Pacific Ocean, and forms a legislative district of the Ratak Chain of the Marshall Islands. Wotje's land area of , is one the largest in the Marshall Islands, and encloses a lagoon of . The atoll is oriented east and west and is at its longest...  on 24-03-1943
  146	I-33	Mitsubishi, Kōbe Shipyard	01-02-1940	01-05-1941	10-06-1942		Lost in an accident at Truk Chuuk Chuuk — formerly Truk, Ruk, Hogoleu, Torres, Ugulat, and Lugulus — is an island group in the south western part of the Pacific Ocean. It comprises one of the four states of the Federated States of Micronesia , along with Kosrae, Pohnpei, and Yap. Chuuk is the most populous of the FSM's...  on 26-09-1942. Salvaged and repaired starting 29-12-1942. Later, lost in another accident at Iyo Nada on 13-06-1944. Salvaged and scrapped starting 28-06-1953
  147	I-34 Japanese submarine I-34 I-34 was a Kaidai Junsen Type B1 class submarine of the Imperial Japanese Navy. During World War II, while on a Yanagi mission between Japan and Germany carrying strategic raw material and information, she was sunk by the British submarine HMS Taurus using Ultra intelligence.-Commissioning:Her keel...	Sasebo Naval Arsenal	09-01-1941	24-09-1941	31-08-1942		Sunk by HMS Taurus HMS Taurus (P399) HMS Taurus was a Second World War British T class submarine, built by Vickers Armstrong, Barrow.-As HMS Taurus:The submarine was laid down on the 30th of September 1941, and launched on 27 June 1942. She served in the Mediterranean and the Pacific Far East during the Second World War...  at Penang Island Penang Island Penang Island is part of the state of Penang, on the west coat of Peninsular Malaysia. It was named Prince of Wales Island when it was occupied by the British East India Company on 12 August 1786, in honour of the birthday of the Prince of Wales, later King George IV...  on 13-11-1943
  148	I-35	Mitsubishi, Kōbe Shipyard	02-09-1940	24-09-1941	31-08-1942		Sunk by USS Meade USS Meade (DD-602) USS Meade was a in the United States Navy during World War II. She was the second ship named for Richard Worsam Meade and Robert Leamy Meade....  and USS Frazier USS Frazier (DD-607) USS Frazier was a Benson-class destroyer in the United States Navy during World War II. She was named for Daniel Frazier.Frazier was launched 17 March 1942 by Bethlehem Steel Corporation, San Francisco, California; sponsored by Mrs...   south of Tarawa on 22-11-1943
  149	I-36	Yokosuka Naval Arsenal	04-12-1940	01-11-1941	30-09-1942	Damaged USS Mazama USS Mazama (AE-9) USS Mazama was laid down 14 April 1942 by the Tampa Shipbuilding Co., Tampa, Fla.; launched 15 August 1943; sponsored by Mrs. Edward V. Rickenbacker; and commissioned 10 March 1944, Comdr: P. V. R. Harris, USNR, in command...  on 09-01-1945 by Kaiten Damaged USS LCI(L)-600 on 09-01-1945 by Kaiten Damaged USS Endymion USS Endymion (ARL-9) USS Endymion was one of 39 Achelous-class landing craft repair ships built for the United States Navy during World War II. Named for Endymion , she was the only U.S...  on 22-06-1945 Damaged USS LST-513 on 22-06-1945 (?)	Converted to the Kaiten Kaiten The Kaiten were manned torpedos and suicide craft, they were used by the Imperial Japanese Navy in the final stages of World War II.-History:...  mother ship on 01-09-1944. Decommissioned on 30-11-1945, sunk as a target off Gotō Islands Goto Islands The are Japanese islands in the East China Sea, off the western coast of Kyūshū. The islands are a part of Nagasaki Prefecture.- Geography :There are 140 islands in total, including five main islands:,,,, and....  on 01-04-1946
  150	I-37	Kure Naval Arsenal	07-12-1940	22-10-1941	10-03-1943	Sank RMS San Ernesto on 16-03-1943 Sank SS Henry Knox on 19-03-1943 Sank Greek merchant ship Faneromeni on 23-10-1943 Sank Norwegian merchant vessl Scotia on 27-11-1943 Sank RMS British Chivalry on 22-02-1944 Sank RMS Sutlej on 26-02-1944 Sank RMS Ascot on 29-02-1944	Converted to the Kaiten mother ship on 09-09-1944. Sunk by USS Conklin USS Conklin (DE-439) USS Conklin was a John C. Butler-class destroyer escort acquired by the U.S. Navy during World War II. The primary purpose of the destroyer escort was to escort and protect ships in convoy, in addition to other tasks as assigned, such as patrol or radar picket...  and USS McCoy Reynolds USS McCoy Reynolds (DE-440) USS McCoy Reynolds was a acquired by the U.S. Navy during World War II. The primary purpose of the destroyer escort was to escort and protect ships in convoy, in addition to other tasks as assigned, such as patrol or radar picket...  north of Palau Palau Palau , officially the Republic of Palau , is an island nation in the Pacific Ocean, east of the Philippines and south of Tokyo. In 1978, after three decades as being part of the United Nations trusteeship, Palau chose independence instead of becoming part of the Federated States of Micronesia, a... , on 19-11-1944
  151	I-38	Sasebo Naval Arsenal	19-06-1941	15-04-1942	31-01-1943		Sunk by USS Nicholas USS Nicholas (DD-449) USS Nicholas was a Fletcher-class destroyer of the United States Navy, which served through most of World War II, and for 27 years and two more wars after. She was the second Navy ship to be named for Major Samuel Nicholas....  east of Luzon Luzon Luzon is the largest island in the Philippines. It is located in the northernmost region of the archipelago, and is also the name for one of the three primary island groups in the country centered on the Island of Luzon...  on 12-11-1944
  152	I-39	Sasebo Naval Arsenal	19-06-1941	15-04-1942	22-04-1943	Sank USS Navajo USS Navajo (AT-64) USS Navajo was an oceangoing tugboat in the United States Navy, and the lead ship of her class. She was named for the Navajo people....  on 12-09-1943	Sunk by USS Boyd USS Boyd (DD-544) USS Boyd was a of the United States Navy, named for Joseph Boyd, who took part in Stephen Decatur's expedition into Tripoli harbor during the First Barbary War....  west of Makin Makin (islands) Makin is the name of a chain of islands located in the Pacific Ocean island nation of Kiribati, specifically in the Gilbert Islands.-Geography:...  at 03°10′N 171°55′E on 16-11-1943
  153							The dummy for the naval budget of the Yamato class battleships

Type-B Mod.1 (I-40 class)

Project number S37B. Six boats were planned under the Maru Kyū Programme (Boats 370 - 375), all boats were completed. On the outside this class looked the same as the I-15 class; however, they were built from high-tensile strength steel and equipped with diesel engines of a simpler design.

• Boats in class

  Boat No.	Boat	Builder	Laid down	Launched	Completed	Results	Fate
  370	I-40	Kure Naval Arsenal	18-03-1942	10-11-1942	31-07-1943		Probably lost in an accident, after 22-11-1943
  371	I-41	Kure Naval Arsenal	18-03-1942	10-11-1942	18-09-1943	Damaged by USS Reno USS Reno (CL-96) USS Reno was an updated Atlanta-class light cruiser - sometimes referred to as the "Oakland-class" - designed and built to specialize in antiaircraft warfare. She was the first warship to be named for the city of Reno, Nevada. The one other USS Reno was a destroyer named for Lt. Commander Walter E...  on 03-11-1944	Sunk by USS Lawrence C. Taylor USS Lawrence C. Taylor (DE-415) USS Lawrence C. Taylor was a acquired by the U.S. Navy during World War II. The primary purpose of the destroyer escort was to escort and protect ships in convoy, in addition to other tasks as assigned, such as patrol or radar picket...  east of the Philippines at 12°44′N 130°42′E on 12-11-1944
  372	I-42	Kure Naval Arsenal	18-03-1942	10-11-1942	03-11-1943		Sunk by USS Tunny USS Tunny (SS-282) The USS Tunny was a Gato-class submarine which saw service in World War II and in the Vietnam War. Tunny received nine battle stars and two Presidential Unit Citations for her World War II service and five battle stars for her operations during the Vietnam War.Tunny was the first submarine of the...  southwest of Palau at 06°40′N 134°03′E on 23-03-1944
  373	I-43	Sasebo Naval Arsenal	27-04-1942	10-25-1942	05-11-1943		Sunk by USS Aspro USS Aspro (SS-309) USS Aspro , a Balao-class submarine, was the first ship of the United States Navy to be named for the aspro, a fish found abundantly in the upper Rhône River. According to legend, the aspro comes to the surface only in bad weather, when other fishes take refuge near the bottom...  north of Truk at 12°42′N 149°17′E on 15-02-1944
  374	I-44	Yokosuka Naval Arsenal	11-06-1942	05-03-1943	31-01-1944	Possibly sank USS Snook USS Snook (SS-279) USS Snook , a Gato-class submarine, was the first ship of the United States Navy to be named for the common snook, an Atlantic marine fish that is bluish-gray above and silvery below a black lateral line....  on 17-04-1945 (?)	Converted to the Kaiten mother ship on 22-10-1944. Sunk by USS Heermann USS Heermann (DD-532) USS Heermann was a World War II-era Fletcher-class destroyer in the service of the United States Navy, named after Fleet Surgeon Lewis Heermann .... , USS Uhlmann USS Uhlmann (DD-687) USS Uhlmann was a World War II-era Fletcher-class destroyer in the service of the United States Navy, named after Ensign Robert W. Uhlmann.-World War II:... , USS Mertz USS Mertz (DD-691) USS Mertz was a World War II-era Fletcher-class destroyer in the service of the United States Navy, named after Rear Admiral Albert Mertz.... , USS Collett USS Collett (DD-730) USS Collett was a World War II-era Allen M. Sumner-class destroyer in the service of the U.S. Navy, named after Lieutenant Commander John A. Collett , a Naval Aviator and commanding officer of Torpedo Squadron TEN, who was killed during the Battle of the Santa Cruz Islands in October 1942...  and aircraft from USS Bataan USS Bataan (CVL-29) USS Bataan , originally planned as USS Buffalo and also classified as CV-29, was an 11,000 ton Independence class light aircraft carrier which was commissioned in the United States Navy during World War II....  north-northwest of Minami Daitō at 12°42′N 149°17′E on 18-04-1945
  375	I-45	Sasebo Naval Arsenal	15-07-1942	06-03-1943	28-12-1943	Damaged USS Santee USS Santee (CVE-29) The second USS Santee was launched on 4 March 1939 as Esso Seakay under a Maritime Commission contract by the Sun Shipbuilding and Dry Dock Company at Chester, Pennsylvania, sponsored by Mrs...  on 25-10-1944 (?) Sank USS Eversole USS Eversole (DE-404) The USS Eversole was a John C. Butler-class destroyer escort built for the United States Navy during World War II. Named for Lieutenant John Thomas Eversole, , she was the first of two U.S...  on 28-10-1944	(1). Sunk by USS Gridley USS Gridley (DD-380) The second USS Gridley was the lead ship of her class of destroyers in the United States Navy. She was named for Charles Vernon Gridley.-History:...  and USS Helm USS Helm (DD-388) USS Helm was a Bagley-class destroyer in the United States Navy during World War II. She was named for Rear Admiral James Meredith Helm. Helm received 11 battle stars for her World War II service in the Pacific.-Pre-war:...   east of the Philippines at 10°10′N 127°28′E on 28-10-1944. (2). Sunk by USS Whitehurst USS Whitehurst (DE-634) USS Whitehurst , a of the United States Navy, was named in honor of Henry Purefoy Whitehurst, Jr. Ensign Whitehurst was a crew member of the when he was killed while his ship participated in the Battle of Savo Island off Guadalcanal in August 1942.-Initial operations:Whitehurst was laid down on...  east of the Philippines on 28-10-1944

Type-B Mod.2 (I-54 class)

Project number S37C. Twenty-one boats were planned under the Maru Kyū Programme

Additional Naval Armaments Supplement Programme (Japan, 1941)

The was one of the naval expansion plans of the Imperial Japanese Navy .-Background:In November 1941, the IJN required many additional submarines for the Pacific War, as a pressing matter. To meet this need, the IJN negotiated with the Ministry of Finance and received approval for 32 submarines...

 (Boats 627 - 636) and Kai-Maru 5 Programme

Modified 5th Naval Armaments Supplement Programme (Japan, 1942)

The was one of the wartime armaments expansion plans of the Imperial Japanese Navy .-Background:In September 1942, after being defeated in the Battle of Midway, the IJN drew up a new armaments expansion plan. This plan was combined by the 5th Naval Armaments Supplement Programme and the 6th Naval...

 (Boats 5101 - 5114). Eighteen boats were cancelled in late 1943, because the IJN was setting the as 1945's main submarines

• Boats in class

  Boat No.	Boat	Builder	Laid down	Launched	Completed	Results	Fate
  627	I-54	Yokosuka Naval Arsenal	01-07-1942	04-05-1943	31-03-1944	Damaged USS Santee USS Santee (CVE-29) The second USS Santee was launched on 4 March 1939 as Esso Seakay under a Maritime Commission contract by the Sun Shipbuilding and Dry Dock Company at Chester, Pennsylvania, sponsored by Mrs...  on 25-10-1944 (?)	(1). Sunk by USS Gridley USS Gridley (DD-380) The second USS Gridley was the lead ship of her class of destroyers in the United States Navy. She was named for Charles Vernon Gridley.-History:...  and USS Helm USS Helm (DD-388) USS Helm was a Bagley-class destroyer in the United States Navy during World War II. She was named for Rear Admiral James Meredith Helm. Helm received 11 battle stars for her World War II service in the Pacific.-Pre-war:...  east of the Philippines at 10°10′N 127°28′E on 28-10-1944 (2). Sunk by USS Whitehurst USS Whitehurst (DE-634) USS Whitehurst , a of the United States Navy, was named in honor of Henry Purefoy Whitehurst, Jr. Ensign Whitehurst was a crew member of the when he was killed while his ship participated in the Battle of Savo Island off Guadalcanal in August 1942.-Initial operations:Whitehurst was laid down on...  east of the Philippines on 28-10-1944
  629	I-56	Yokosuka Naval Arsenal	29-09-1942	30-06-1943	08-06-1944	Damaged USS LST-695 on 24-10-1944 Damaged USS Santee USS Santee (CVE-29) The second USS Santee was launched on 4 March 1939 as Esso Seakay under a Maritime Commission contract by the Sun Shipbuilding and Dry Dock Company at Chester, Pennsylvania, sponsored by Mrs...  on 25-10-1944 (?)	Converted to the Kaiten mother ship on 14-11-1944. Sunk by USS Hudson USS Hudson (DD-475) USS Hudson , a Fletcher-class destroyer, was the second ship of the United States Navy to be named for Captain William L. Hudson ....  at Kumejima Island Kumejima Island is an island, part of the Okinawa Islands and administratively in the Okinawa Prefecture, Japan. It has an area of 59.11 km². It belongs to the Ryukyu Islands . The main town Kumejima has a population of 8,713 .... , at 26°22′N 126°30′E on 05-04-1945
  631	I-58 Japanese submarine I-58 I-58 was a Japanese B3 type cruiser submarine that served in the final year of World War II. Modified to carry Kaiten manned torpedoes, she damaged two enemy destroyers with them, but her most significant success was the , sunk with conventional torpedoes on 30 July 1945...	Yokosuka Naval Arsenal	26-12-1942	09-10-1943	07-09-1944	Damaged USS Lowry USS Lowry (DD-770) USS Lowry , an , is the only ship of the United States Navy to be named for Reigart Bolivar Lowry, who served in the Mexican-American War and was a member of Commodore Matthew C. Perry's expedition to Japan in 1855...  on 28-07-1945 by Kaiten Sank USS Indianapolis USS Indianapolis (CA-35) USS Indianapolis was a of the United States Navy. She holds a place in history due to the circumstances of her sinking, which led to the greatest single loss of life at sea in the history of the U.S. Navy...  on 30-07-1945 Damaged USS Thomas F. Nickel USS Thomas F. Nickel (DE-587) USS Thomas F. Nickel was a of the United States Navy named in honor of Private Thomas F. Nickel, United States Marine Corps, who was killed in the Pacific War in 1942 and posthumously awarded a Silver Star....  on 12-08-1945 by Kaiten (?)	Converted to the Kaiten mother ship, before completion. Decommissioned on 30-11-1945, sunk as a target off the Gotō Islands on 01-04-1946
  633 - 636							Cancelled in 1943
  5101 - 5114

V22A Type

Project number S49A. Eighteen boats were planned under the Kai-Maru 5 Programme

Modified 5th Naval Armaments Supplement Programme (Japan, 1942)

The was one of the wartime armaments expansion plans of the Imperial Japanese Navy .-Background:In September 1942, after being defeated in the Battle of Midway, the IJN drew up a new armaments expansion plan. This plan was combined by the 5th Naval Armaments Supplement Programme and the 6th Naval...

 (Boats 5115 - 5132). However, all boats were cancelled in late 1943, because the IJN concentrated on production of from 1945 onwards

• Boats in class

  Boat No.	Boat	Builder	Laid down	Launched	Completed	Fate
  5115 - 5132						Cancelled in 1943

Characteristics

Type		Type-B (I-15)	Type-B Mod. 1 (I-40)	Type-B Mod. 2 (I-54)	V22A Type
Displacement	Surfaced	2198 long tons (2,233 t)	2230 long tons (2,266 t)	2140 long tons (2,174 t)	2330 long tons (2,367 t)
	Submerged	3654 long tons (3,713 t)	3700 long tons (3,759 t)	3688 long tons (3,747 t)	No data
Length (overall)		108.7 metre	108.7 metre	108.7 metre	106.5 metre (waterline)
Beam		9.3 metre	9.3 metre	9.3 metre	9.64 metre
Draft		5.14 metre	5.2 metre	5.19 metre	5.32 metre
Depth		7.9 metre	7.9 metre	7.9 metre	No data
Power plant and shaft		2 × Kampon Imperial Japanese Navy Technical Department The was the externally operating division of the Ministry of the Navy of Japan responsible for the administration of naval vessel construction. From 1923 onward, it took on the role of a research institution for the research and development of naval technologies and engineering...  Mk. 2 Model 10 diesels 2 shafts	2 × Kampon Mk. 1A Model 10 diesels 2 shafts	2 × Kampon Mk. 22 Model 10 diesels 2 shafts	2 × Kampon Mk. 2 Model 10 diesels 2 shafts
Power	Surfaced	12,400 bhp	11,000 bhp	4,700 bhp	11,000 bhp
	Submerged	2,000 shp	2,000 shp	1,200 shp	2,400 shp
Speed	Surfaced	23.6 knots (46.3 km/h)	23.5 knots (46.1 km/h)	17.7 knots (34.7 km/h)	22.4 knots (43.9 km/h)
	Submerged	8 knots (15.7 km/h)	8 knots (15.7 km/h)	6.5 knots (12.7 km/h)	8 knots (15.7 km/h)
Range	Surfaced	14000 nmi (25,928 km) at 16 knots (31.4 km/h)	14000 nmi (25,928 km) at 16 knots (31.4 km/h)	21000 nmi (38,892 km) at 16 knots (31.4 km/h)	14000 nmi (25,928 km) at 16 knots (31.4 km/h)
	Submerged	96 nmi (177.8 km) at 3 knots (5.9 km/h)	96 nmi (177.8 km) at 3 knots (5.9 km/h)	105 nmi (194.5 km) at 3 knots (5.9 km/h)	80 nmi (148.2 km) at 3 knots (5.9 km/h)
Test depth		100 m (328.1 ft)	100 m (328.1 ft)	100 m (328.1 ft)	100 m (328.1 ft)
Fuel		774 tons	814 tons	842.8 tons	735 tons
Complement		94	94	94	No data
Armament (initial)		• 6 × 533 mm (21 in) Torpedo tube Torpedo tube A torpedo tube is a device for launching torpedoes. There are two main types of torpedo tube: underwater tubes fitted to submarines and some surface ships, and deck-mounted units installed aboard surface vessels... s (6 × front) • 17 × Type 95 torpedo Type 95 torpedo The Type 95 torpedo was a torpedo of the Imperial Japanese Navy.It was based on the formidable Type 93 torpedo but had a smaller warhead, shorter range and a smaller diameter... es • 1 × 140 mm (5.5 in) L/40 11th Year Type Naval gun • 2 × Type 96 25mm AA guns	• 6 × 533 mm (21 in) TTs (6 × front) • 17 × Type 95 torpedoes • 1 × 140 mm (5.5 in) L/40 11th Year Type Naval gun • 2 × Type 96 25mm AA guns	• 6 × 533 mm (21 in) TTs (6 × front) • 19 × Type 95 torpedoes • 1 × 140 mm (5.5 in) L/40 11th Year Type Naval gun • 2 × Type 96 25mm AA guns	• 8 × 533 mm (21 in) TTs (8 × front) • 16 × torpedoes • 1 × 140 mm Naval gun • 4 × 25mm AA guns • 8 × naval mine Naval mine A naval mine is a self-contained explosive device placed in water to destroy surface ships or submarines. Unlike depth charges, mines are deposited and left to wait until they are triggered by the approach of, or contact with, an enemy vessel... s
Aircraft and facilities		• Catapult and hangar • 1 × Watanabe E9W1 Slim Watanabe E9W |-See also:-Bibliography:...  seaplane	• Catapult and hangar • 1 × Yokosuka E14Y2 Glen Yokosuka E14Y |-See also:-References:NotesBibliography* Francillon, Ph.D., René J. Japanese Aircraft of the Pacific War. London: Putnam & Company Ltd., 1979. ISBN 0-370-30251-6.... seaplane	• Catapult and hangar • 1 × Yokosuka E14Y2 Glen seaplane	• Catapult and hangar • 1 × floatplane