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I-400 class submarine

I-400 class submarine

Overview


The Imperial Japanese Navy submarines
Imperial Japanese Navy submarines
Imperial Japanese Navy submarines originated with the purchase of five Holland type submarines from the United States in 1904. Japanese submarine forces progressively built up strength and expertise, becoming by the beginning of World War II one of the world's most varied and powerful submarine...

 were the largest submarines of 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...

 and remained the largest ever built until the construction of nuclear ballistic missile submarine
Ballistic missile submarine
A ballistic missile submarine is a submarine equipped to launch ballistic missiles .-Description:Ballistic missile submarines are larger than any other type of submarine, in order to accommodate SLBMs such as the Russian R-29 or the American Trident...

s in the 1960s. They were submarine aircraft carrier
Submarine aircraft carrier
Submarine aircraft carriers are submarines equipped with fixed wing aircraft for observation or attack missions. These submarines saw their most extensive use during World War II, although their operational significance remained rather small...

s able to carry three Aichi M6A
Aichi M6A
The Aichi M6A Seiran was a submarine-launched attack floatplane designed for the Imperial Japanese Navy during World War II...

 Seiran aircraft underwater to their destinations. They were designed to surface, launch the planes then dive again quickly before they were discovered. They also carried torpedo
Torpedo
The modern torpedo is a self-propelled missile weapon with an explosive warhead, launched above or below the water surface, propelled underwater towards a target, and designed to detonate either on contact with it or in proximity to it.The term torpedo was originally employed for...

es for close-range combat.

The I-400-class was designed with the range to travel anywhere in the world and return.
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Encyclopedia


The Imperial Japanese Navy submarines
Imperial Japanese Navy submarines
Imperial Japanese Navy submarines originated with the purchase of five Holland type submarines from the United States in 1904. Japanese submarine forces progressively built up strength and expertise, becoming by the beginning of World War II one of the world's most varied and powerful submarine...

 were the largest submarines of 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...

 and remained the largest ever built until the construction of nuclear ballistic missile submarine
Ballistic missile submarine
A ballistic missile submarine is a submarine equipped to launch ballistic missiles .-Description:Ballistic missile submarines are larger than any other type of submarine, in order to accommodate SLBMs such as the Russian R-29 or the American Trident...

s in the 1960s. They were submarine aircraft carrier
Submarine aircraft carrier
Submarine aircraft carriers are submarines equipped with fixed wing aircraft for observation or attack missions. These submarines saw their most extensive use during World War II, although their operational significance remained rather small...

s able to carry three Aichi M6A
Aichi M6A
The Aichi M6A Seiran was a submarine-launched attack floatplane designed for the Imperial Japanese Navy during World War II...

 Seiran aircraft underwater to their destinations. They were designed to surface, launch the planes then dive again quickly before they were discovered. They also carried torpedo
Torpedo
The modern torpedo is a self-propelled missile weapon with an explosive warhead, launched above or below the water surface, propelled underwater towards a target, and designed to detonate either on contact with it or in proximity to it.The term torpedo was originally employed for...

es for close-range combat.

The I-400-class was designed with the range to travel anywhere in the world and return. A fleet of 18 boats was planned in 1942, and work started on the first in January 1943 at the Kure, Hiroshima
Kure, Hiroshima
is a city in Hiroshima prefecture, Japan.As of October 1, 2010, the city has an estimated population of 240,820 and a population density of 681 persons per km². The total area is 353.74 km².- History :...

 arsenal. Within a year the plan was scaled back to five, of which only three (I-400 at Kure, and I-401
Japanese submarine I-401
The Sen Toku-class I-401 was once the largest submarine in the world. It was commanded by Lieutenant Commander Nobukiyo Nambu of the Imperial Japanese Navy during World War II...

 and I-402 at Sasebo) were completed.

Origins


The I-400 class submarine was the brainchild of Admiral Isoroku Yamamoto
Isoroku Yamamoto
was a Japanese Naval Marshal General and the commander-in-chief of the Combined Fleet during World War II, a graduate of the Imperial Japanese Naval Academy and a student of Harvard University ....

, Commander-in-Chief of the Japanese Combined Fleet. Shortly after the attack on Pearl Harbor in December 1941, he conceived the idea of taking the war to the United States mainland by making aerial attacks against cities along the US western and eastern seaboards using submarine-launched naval aircraft. He commissioned Captain Kameto Kuroshima to make a feasibility study.
Yamamoto submitted the resulting proposal to Fleet Headquarters on 13 January 1942. It called for a fleet of 18 large submarines capable of making three round-trips to the west coast of the United States without refueling or one round-trip to any point on the globe. They had also to be able to store and launch at least two attack aircraft armed with one torpedo or 800 kg (1,763.7 lb) bomb. By 17 March general design plans for the submarines were finalized. Construction of I-400 commenced at Kure Dock Yards on 18 January 1943, and four more boats followed: I-401 (April 1943) and I-402 (Oct 1943) at Sasebo; I-403 (Sept 1943) at Kobe and I-404 (February 1944) at Kure. Only three were completed.
Following Yamamoto's death during an inspection tour of the Solomon Islands in April 1943, the number of aircraft-carrying submarines to be built was reduced from eighteen to nine, then five and finally three. Only I-400 and I-401 actually entered service; I-402 was completed on 24 July 1945, three weeks before the end of the war, but never made it to sea.

Characteristics


Each submarine had four 1680 kW engines and carried enough fuel to go around the world one-and-a-half times—more than enough to reach the United States travelling east or west. Measuring more than 120 m (393.7 ft) long overall, they displaced 5900 tonne, more than double their typical American contemporaries. The cross-section of its pressure hull had a unique figure-of-eight shape which afforded the necessary strength and stability to handle the weight of a large on-deck aircraft hangar. To allow stowage of three aircraft along the vessel's centreline, the conning tower was offset to port.
Located approximately amidships on the top deck was a cylindrical watertight aircraft hangar, 31 m (101.7 ft) long and 3.5 m (11.5 ft) in diameter. The outer access door could be opened hydraulically from within or manually from the outside by turning a large hand-wheel connected to a rack and spur gear. The door was made waterproof with a 51 millimetre rubber gasket.
Sited atop the hangar were three water-proofed Type 96 triple-mount 25 mm (0.984251968503937 in) autocannon
Autocannon
An autocannon or automatic cannon is a rapid-fire projectile weapon firing a shell as opposed to the bullet fired by a machine gun. Autocannons often have a larger caliber than a machine gun . Usually, autocannons are smaller than a field gun or other artillery, and are mechanically loaded for a...

 for AA defence, two abaft and one forward the conning tower. A single 25 mm (0.984251968503937 in) autocannon on a pedestal mount was also located just abaft the bridge. One Type 11, 140 mm (5.5 in) deck gun was positioned aft of the hangar. It had a range of 15000 m (49,212.6 ft).
Eight torpedo tubes were mounted in the bow, four above and four below. There were no aft tubes.
Stowed in an open recessed compartment on the forward port side, just below top deck, was a collapsible crane used to retrieve the submarine's Seiran floatplanes. The crane had an electrically operated hoist and was capable of lifting approximately 4.5 tonne. It was raised mechanically to a height of 8 m (26.2 ft) via a motor inside the boat. The boom extended out to a length of 11.8 m (38.7 ft).
A special trim system was fitted to the boats, allowing them to loiter submerged and stationary while awaiting the return of their aircraft. However, operation of this system was noisy and its usefulness was in doubt.
Strung along the submarine's gunwales were two parallel sets of demagnetization cables, running from the stern to the bow planes. These were intended to dissipate the static charge that normally builds up when a boat's hull slices through the water, causing the steel in the hull to deteriorate over time.
Electronics on board the I-400s included a Mark 3 Model 1 air search radar equipped with two separate antennas. This unit was capable of detecting aircraft out to a range of 80 km (43.2 nmi), though Japanese operators later admitted that planes flying below the radar horizon could escape detection altogether. The boats were also equipped with Mark 2 Model 2 air/surface radar sets with distinctive horn-shaped antennas. Each boat carried an E27 radar warning receiver
Radar warning receiver
Radar warning receiver systems detect the radio emissions of radar systems. Their primary purpose is to issue a warning when a radar signal that might be a threat is detected. The warning can then be used, manually or automatically, to evade the detected threat...

, connected to both a trainable dipole antenna and a fixed non-directional antenna made up of a wire mesh basket and two metal rods.
The submarines were equipped with two periscopes of German manufacture, about 12.2 m (40 ft) long, one for use during daylight and the other at night.
A special anechoic coating made from a mixture of gum, asbestos, and adhesives, based on German technology, was applied to the hulls from the waterline to the bilge keel. This was intended to absorb or diffuse enemy sonar pulses and dampen reverberations from the boat's internal machinery, making detection while submerged more difficult.
In May 1945, I-401 was fitted with a German-supplied snorkel
Submarine snorkel
A submarine snorkel is a device which allows a submarine to operate submerged while still taking in air from above the surface. Navy personnel often refer to it as the snort.-History:...

, a hydraulically-raised air intake device allowing the boat to run its diesel engines and recharge its batteries while remaining at periscope depth. This retrofit occurred while the boat was laid up at Kure for repairs after being damaged by an American mine in April.
I-402 was completed immediately before the war ended, but had been converted during building to a tanker and was never equipped with aircraft.

The aircraft


The hangar of the I-400s was originally designed to hold two aircraft. In 1943, however, Commander Yasuo Fujimori, Submarine Staff Officer of the Naval General Staff, requested it be enlarged. This was deemed feasible and, as remodelled, I-400s could stow up to three Aichi M6A Seiran
Aichi M6A
The Aichi M6A Seiran was a submarine-launched attack floatplane designed for the Imperial Japanese Navy during World War II...

 aircraft
Aircraft
An aircraft is a vehicle that is able to fly by gaining support from the air, or, in general, the atmosphere of a planet. An aircraft counters the force of gravity by using either static lift or by using the dynamic lift of an airfoil, or in a few cases the downward thrust from jet engines.Although...

.
The Seiran was specifically designed for use aboard the submarines and could carry an 800 kg (1,763.7 lb) bomb 1000 km (621.4 mi) at 475 km/h (295.2 mph). To fit inside the narrow confines of the hangar, the wings rotated 90 degrees and folded backward hydraulically against the fuselage, the horizontal stabilizers folded down and the top of the vertical stabilizer folded over so the overall forward profile of the aircraft was within the diameter of its propeller. When deployed for flight, the aircraft had a wing span of 12 m (39.4 ft) and a length of 11.6 m (38.1 ft). A crew of four could prepare and launch all three in 45 minutes (or 15 minutes if the planes' pontoons were not attached). As the Seiran would normally be launched at night, parts and areas of the plane were coated with luminescent paint in order to ease assembly in the dark.
The Seirans were launched from a 26 m (85.3 ft) Type 4 No. 2 Model 10 compressed-air catapult
Aircraft catapult
An aircraft catapult is a device used to launch aircraft from ships—in particular aircraft carriers—as a form of assisted take off. It consists of a track built into the flight deck, below which is a large piston or shuttle that is attached through the track to the nose gear of the aircraft, or in...

 on the forward deck of the submarine. Underneath the catapult track were four high-pressure air flasks connected in parallel to a piston. The aircraft, mounted atop collapsible carriages via catapult attachment points along their fuselages, would be slung 70–75 feet along the track, though the piston itself only moved between eight and ten feet during operation.
Two sets of pontoons for the Seirans were stored in special watertight compartments located just below the main deck on either side of the catapult track. From there they could be quickly slid forward on ramps and attached to the plane's wings. A third set of pontoons and additional spares were kept inside the hangar.
The existence of the Seiran was not known to Allied intelligence during the war.

Operational history


As the war turned against the Japanese and their fleet no longer had free rein in the Pacific, the Commander-in-Chief of the Japanese Combined Fleet, Admiral Isoroku Yamamoto
Isoroku Yamamoto
was a Japanese Naval Marshal General and the commander-in-chief of the Combined Fleet during World War II, a graduate of the Imperial Japanese Naval Academy and a student of Harvard University ....

, devised a daring plan to attack the cities of New York
New York
New York is a state in the Northeastern region of the United States. It is the nation's third most populous state. New York is bordered by New Jersey and Pennsylvania to the south, and by Connecticut, Massachusetts and Vermont to the east...

, Washington D.C., and other large American cities.


Panama Canal strike


Following an inspection of Rabaul in August 1943, Capt. Chikao Yamamoto and Commander Yasuo Fujimori conceived the idea of using the sen toku (secret submarine attack) to destroy the locks of the Panama Canal
Panama Canal
The Panama Canal is a ship canal in Panama that joins the Atlantic Ocean and the Pacific Ocean and is a key conduit for international maritime trade. Built from 1904 to 1914, the canal has seen annual traffic rise from about 1,000 ships early on to 14,702 vessels measuring a total of 309.6...

 in an attempt to cut American supply lines to the Pacific Ocean
Pacific Ocean
The Pacific Ocean is the largest of the Earth's oceanic divisions. It extends from the Arctic in the north to the Southern Ocean in the south, bounded by Asia and Australia in the west, and the Americas in the east.At 165.2 million square kilometres in area, this largest division of the World...

 and hamper the transfer of U.S. ships. Intelligence gathering on this proposed target began later that year.

The Japanese were well aware that American fortifications existed on both sides of the Canal. On the Atlantic side the large coastal artillery batteries of Fort Sherman had a range of 30,000 yards (17 miles (27.4 km)), preventing enemy ships from getting near enough to shell the locks. In the months following the attack on Pearl Harbor, air and sea patrols had been strengthened around both entrances, and barrage balloons and anti-submarine nets erected. In August 1942 the 88th Coast (Anti-Aircraft) Artillery unit was added to help defend against aerial attacks.

However, as the war continued and Japan's fortunes declined, security around the Canal grew increasingly lax. In January 1944 Commander Fujimori personally interviewed an American POW who had done guard duty there. He told Fujimori that defensive air patrols had virtually ceased as it was considered increasingly unlikely the Axis powers would ever attempt an attack on the locks. This further convinced Fujimori of his plan's feasibility.

A Japanese engineer who had worked on the Canal during its construction handed over hundreds of documents to the Naval General Staff, including blueprints of the Canal structures and construction methods. A team of three shipping engineers studied these documents and concluded that, although the locks at Miraflores on the Pacific side were the most vulnerable to aerial bombing, the Gatun locks on the Atlantic side offered a chance of causing greater damage since it would be harder to halt any outflow of water. They estimated the Canal would be unusable for at least six months following a successful attack.

To increase the size of the airborne attack force, Commander Fujimori requested that two additional fleet submarines still under construction at Kobe, I-13 and I-14, be modified to house two Seirans each, bringing the total number of planes available to ten. It was originally planned that two of the Seirans would carry torpedoes and the other eight would carry 800 kg (1,763.7 lb) bombs. They were to make a combined torpedo and glide-bombing attack against the Gatun Locks. Eventually though, torpedo-bombing was dispensed with, as only one Seiran pilot had mastered the technique.

The Panama Canal strike plan called for four aircraft-carrying submarines (I-400, I-401, I-13 and I-14) to sail eastward across the Pacific to the Gulf of Panama, a journey expected to take two months. At a point 185 km (99.9 nmi) off the coast of Ecuador, the submarines would launch their Seiran aircraft at 0300hrs on a moonlit night. The Seirans, without floats, would fly at an altitude of 4000 m (13,123.4 ft) across the northern coast of Colombia to the vicinity of Colón. Now on the Caribbean side of the isthmus, they would turn westward on a heading of 270 degrees, then angle south-west and make their final approach to the Canal locks at dawn. After completing their bombing runs, the Seirans were to return to a designated rendezvous point and ditch alongside the waiting submarines where the aircrews would be picked up.

Around April 1945 Captain Ariizumi, the man appointed to carry out the attack, decided the Seiran pilots would make kamikaze ramming attacks against the gates, rather than conventional bombing runs, a tactic becoming increasingly common as the war went against the Japanese. The Seiran squadron leader had already suggested as much to Ariizumi earlier that month, though for a time this was kept secret from the other pilots. At the end of May, however, one pilot happened to observe a Seiran having its bomb-release mechanism removed and replaced with a fixed mount. Realizing the implications of this change, he angrily confronted the executive officer of the squadron, who explained the decision to withhold this intention from the other men was made to "avoid mental pressures on the aircrews."

By 5 June 1945 all four aircraft-carrying submarines had arrived at Nanao Wan where a full-scale wooden model of the Gatun Locks gate had been built by the Maizuru Naval Arsenal, placed on a raft and towed into the bay. The following night, formal training commenced with the Seiran flight crews practising rapid assembly, catapult launch and recovery of their aircraft. There was also rudimentary formation flying. From 15 June the Seiran pilots made practice daylight bombing runs against the wooden gate mock-up. By 20 June all training ended and the operation was set to proceed.

Ulithi atoll


Before the attack could commence from the Japanese naval base at Maizuru, Okinawa fell, and word reached Japan that the Allies were preparing an assault on the Japanese home islands; the Japanese Naval General Staff concluded that the Panama Canal attack would have little impact on the war's outcome, and more direct and immediate action was necessary to stem the American advance.

Fifteen American aircraft carriers had assembled at Ulithi
Ulithi
Ulithi is an atoll in the Caroline Islands of the western Pacific Ocean, about 191 km east of Yap. It consists of 40 islets totalling , surrounding a lagoon about long and up to wide—at one of the largest in the world. It is administered by the state of Yap in the Federated States of...

 atoll, preparatory to making a series of raids against the home islands; the Japanese mission was changed to attack the Ulithi
Ulithi
Ulithi is an atoll in the Caroline Islands of the western Pacific Ocean, about 191 km east of Yap. It consists of 40 islets totalling , surrounding a lagoon about long and up to wide—at one of the largest in the world. It is administered by the state of Yap in the Federated States of...

 base.

The attack on Ulithi Atoll was to take place in two phases. The first, codenamed Hikari (light), involved transporting four C6N Saiun (Myrt)
Nakajima C6N
-See also:-References:NotesBibliography* Francillon, Ph.D., René J. Japanese Aircraft of the Pacific War. London: Putnam & Company Ltd., 1970. ISBN 0-370-00033-1 ....

 single-engined high-speed reconnaissance planes to Truk Island. They were to be disassembled, crated and loaded into the water-tight hangars of submarines I-13 and I-14. Upon reaching Truk, the Saiuns would be unloaded, reassembled and then flown over Ulithi to confirm the presence of American carriers anchored there. Following this delivery, I-13 and I-14 were to sail for Hong Kong where they would embark four Seiran attack planes. They would then head to Singapore and join I-400 and I-401 for further operations.

The second phase of the Ulithi attack was codenamed Arashi (storm). I-400 and I-401 were to rendezvous at a predetermined point on the night of 14/15 August. On 17 August they would launch their six Seirans before daybreak on a one-way kamikaze mission against the American carriers. The Seirans, each with a 800 kg (1,763.7 lb) bomb bolted to its fuselage, were to fly less than 50 m (164 ft) above the water in order to avoid radar detection and the American fighters expected to be patrolling 4000 m (13,123.4 ft) above.

In addition, just before departing Maizuru Naval Station, the Seirans were completely over-painted in silver with American stars and bars insignias covering up the red Hinomarus
Flag of Japan
The national flag of Japan is a white rectangular flag with a large red disk in the center. This flag is officially called in Japanese, but is more commonly known as ....

. This was an attempt to further confuse recognition should the aircraft be prematurely spotted but it was not a popular decision with the aircrew. Some felt it was not only unnecessary but also a personal insult to fly under American naval markings and dishonourable to the Imperial Navy.

Following the attack on Ulithi, I-400 and I-401 would head for Hong Kong where they would embark six new Seirans. From there they were to sail for Singapore, where fuel oil was more readily available. They would then join up with I-13 and I-14 and stage further attacks with a combined force of ten Seiran aircraft.

On 22 June, I-13 and I-14 arrived at Maizuru Harbor to take on fuel. They reached Ominato on 4 July to pick up their Saiun reconnaissance aircraft. I-13 departed for Truk on 11 July but never reached her destination. She was detected running on the surface, attacked and damaged by radar-equipped TBM Avengers on 16 July. An American destroyer escort later arrived and sank the sub with depth-charges.

Ultimately, Japan surrendered before the Ulithi attack was launched, and on August 22, 1945 the crews of the submarines were ordered to destroy all their weapons. The torpedoes were fired without arming and the aircraft were launched without unfolding the wings and stabilizers. When I-400 surrendered to an American destroyer, the U.S. crew was astounded at its size.

American inspections


The U.S. Navy boarded and recovered 24 submarines including the three I-400 submarines, taking them to Sasebo Bay
Sasebo, Nagasaki
is a city located in Nagasaki Prefecture, Japan. As of 2011, the city has an estimated population of 259,800 and the density of 609 persons per km². The total area is 426.47 km². The locality is famed for its scenic beauty. The city includes a part of Saikai National Park...

 to study them. While there, they received a message that the Soviets were sending an inspection team to examine the submarines. To prevent this Operation Road's End was instituted: most of the submarines were taken to a position designated as Point Deep Six, about 60 km (32.4 nmi) west of Nagasaki and off the 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....

, packed with charges of C-2 explosive
Composition C
The Composition C family is a family of related US-specified plastic explosives consisting primarily of RDX. All can be moulded by hand for use in demolition work and packed by hand into shaped charge devices. Variants have different proportions and plasticisers and include C-2, C-3, and C-4.The...

 and destroyed; they sank to a depth of 200 m (656.2 ft).

Four remaining submarines, I-400, I-401, I-201
I-200 class submarine
The were submarines of the Imperial Japanese Navy during World War II. These submarines were of advanced design, built for high underwater speed, and were known as or...

 and I-203
I-200 class submarine
The were submarines of the Imperial Japanese Navy during World War II. These submarines were of advanced design, built for high underwater speed, and were known as or...

, were sailed to Hawaii by U.S. Navy technicians for further inspection. Upon completion of the inspections, the submarines were scuttled
Scuttling
Scuttling is the act of deliberately sinking a ship by allowing water to flow into the hull.This can be achieved in several ways—valves or hatches can be opened to the sea, or holes may be ripped into the hull with brute force or with explosives...

 in the waters off Kalaeloa near Oahu
Oahu
Oahu or Oahu , known as "The Gathering Place", is the third largest of the Hawaiian Islands and most populous of the islands in the U.S. state of Hawaii. The state capital Honolulu is located on the southeast coast...

 in Hawaii
Hawaii
Hawaii is the newest of the 50 U.S. states , and is the only U.S. state made up entirely of islands. It is the northernmost island group in Polynesia, occupying most of an archipelago in the central Pacific Ocean, southwest of the continental United States, southeast of Japan, and northeast of...

 by torpedoes from US submarine on June 4, 1946, apparently because Soviet scientists were again demanding access to them.

Artifacts


The wreckage of I-401 was discovered by the Pisces deep-sea submarines of the Hawaii Undersea Research Laboratory in March 2005 at a depth of 820 meters.

A restored Seiran airplane is displayed at the National Air and Space Museum
National Air and Space Museum
The National Air and Space Museum of the Smithsonian Institution holds the largest collection of historic aircraft and spacecraft in the world. It was established in 1976. Located in Washington, D.C., United States, it is a center for research into the history and science of aviation and...

 in Washington, D.C.
Washington, D.C.
Washington, D.C., formally the District of Columbia and commonly referred to as Washington, "the District", or simply D.C., is the capital of the United States. On July 16, 1790, the United States Congress approved the creation of a permanent national capital as permitted by the U.S. Constitution....

. It is the only surviving example of this aircraft, and was found at the Aichi Aircraft Factory following the end of the war in August 1945. Shipped to the Naval Air Station at Alameda California
Naval Air Station Alameda
Naval Air Station Alameda was a United States Navy Naval Air Station in Alameda, California, on San Francisco Bay.NAS Alameda had two runways: 07-25 and 13-31...

, it was left on outdoor display until 1962 when it was transferred to the Paul E. Garber Facility in Silver Hill, Maryland. There it remained in storage until 1989 when a comprehensive restoration effort was mounted. Though the plane had been ravaged by weather and souvenir collectors, and original factory drawings were lacking, the restoration team was able to reconstruct it accurately, and by February 2000 it was ready for display.

Boats in class

Boat # Boat Builder Laid down Launched Completed Fate
5231 I-400 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...

18 January 1943 18 January 1944 30 December 1944 Captured by USS Blue
USS Blue (DD-744)
USS Blue , an Allen M. Sumner-class destroyer, was the second United States Navy ship of that name, for Lieutenant Commander John S. Blue ....

 on 19 August 1945, decommissioned on 15 September 1945, sunk as a target off the Hawaiian Islands by USS Trumpetfish
USS Trumpetfish (SS-425)
USS Trumpetfish , a Balao-class submarine, was the only ship of the United States Navy to be named for trumpetfish, any of several fishes so-called for their deep, compressed body and long, tubular snout. Her keel was laid down on 23 August 1943 at Philadelphia, Pennsylvania, by the Cramp...

 on 4 June 1946.
5232 I-401 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...

26 April 1943 11 March 1944 8 January 1945 Captured by USS Segundo
USS Segundo (SS-398)
USS Segundo , a Balao-class submarine, was a ship of the United States Navy named for the segundo, a cavalla fish of Caribbean waters....

 on 29 (or 30) August 1945, decommissioned on 15 September 1945, sunk as a target off the Hawaiian Islands on 31 May 1946.
5233 I-402
Japanese Submarine I-402
Imperial Japanese Navy submarine I-402, was one of three completed Sen Toku I-400 class submarine aircraft carriers, which proved to be the largest prior to nuclear submarine development. Each were able to carry three Aichi M6A Seiran floatplanes...

Sasebo Naval Arsenal 20 October 1943 5 September 1944 24 July 1945 Converted to the tanker submarine in June 1945, decommissioned on 15 November 1945, sunk as a target off the 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 1 April 1946.
5234 I-403 Cancelled in October 1943.
5235 I-404 Kure Naval Arsenal 8 November 1943 7 July 1944 Construction stopped on 4 June 1945 (95 % complete). Heavy damaged by air raid
Bombing of Kure (July 1945)
The bombing of Kure and surrounding areas by United States and British naval aircraft in late July 1945 led to the sinking of most of the surviving large warships of the Imperial Japanese Navy . The United States Third Fleet's attacks on Kure Naval Arsenal and nearby ports on 24, 25, and 28 July...

 on 28 July 1945, later scuttled. Salvaged and scrapped in 1952.
5236 I-405 Kawasaki
Kawasaki Shipbuilding Corporation
-External links:*...

, Senshū
Izumi Province
was a province of Japan. It is also referred to as . It lay in Kinai, and its area today composes the south-western part of Osaka Prefecture . The Ōshōji in Sakai was the border with Settsu Province, until the beginning of the Meiji period, when the boundary was changed to be at the Yamato River...

 Shipyard
27 September 1943 Construction stopped and scrapped.
5237
5238
5239
5240
I-406
I-407
I-408
I-409
Cancelled in October 1943.
5241-5248 Cancelled in July 1943.

See also

  • AM type submarine IJN two-aircraft submarine seaplane tender
  • Submarine aircraft carrier
    Submarine aircraft carrier
    Submarine aircraft carriers are submarines equipped with fixed wing aircraft for observation or attack missions. These submarines saw their most extensive use during World War II, although their operational significance remained rather small...

  • French submarine Surcouf

External links