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65-855: The Nab Tower is a tower originally planned for anti- submarine protection in the English Channel in World War I . It was sunk over the Nab rocks east of the Isle of Wight to replace a lightship after the war, and is a well-known landmark for sailors as it marks the deep-water eastern entry into the Solent. During the First World War , the British Admiralty designed eight towers codenamed M-N that were to be built and positioned in

130-420: A cruise missile ); and covert insertion of frogmen or special forces . Their civilian uses include: marine science ; salvage ; exploration; and facility inspection and maintenance. Submarines can be modified for specialized functions such as search-and-rescue missions and undersea cable repair. They are also used in the tourism industry and in undersea archaeology . Modern deep-diving submarines derive from

195-401: A helicopter pad was constructed on the tower and a new pre-fabricated lantern-tower was installed containing an automated acetylene lamp ; as well as powering the lamp, acetylene gas drove the revolving mechanism for the lightweight GRP optic in which the lamp was set. In 1995 the light was converted to solar power operation and a new Orga rotating beacon was installed in the lantern (later

260-493: A Vega VRB-25 rotating beacon was used). In November 1999, the merchant freighter Dole America , carrying a cargo of bananas and pineapples , hit the Nab. The ship was badly damaged and only avoided sinking by being run aground. The base of the tower suffered superficial and internal damage. The damage was repaired in 2001. The tower was featured as the main setting of the 1951 Hammer thriller The Dark Light . In 2013, Trinity House commissioned BAM Nuttall to undertake

325-407: A carrying capacity of 50 to 100 passengers. In a typical operation a surface vessel carries passengers to an offshore operating area and loads them into the submarine. The submarine then visits underwater points of interest such as natural or artificial reef structures. To surface safely without danger of collision the location of the submarine is marked with an air release and movement to the surface

390-475: A hand-powered acorn-shaped device designed by the American David Bushnell to accommodate a single person. It was the first verified submarine capable of independent underwater operation and movement, and the first to use screws for propulsion. In 1800, France built Nautilus , a human-powered submarine designed by American Robert Fulton . They gave up on the experiment in 1804, as did

455-428: A major refurbishment programme due to extensive corrosion of the upper levels, meaning it was unsafe to land helicopters upon the helipad. Partial dismantling of the structure followed, undertaken with the help of a tower crane , which was installed within a former ammunition shaft. The height of the tower was reduced from 27 metres to 17, all external steel and cladding were removed and the existing concrete sub-structure

520-636: A noun it generally refers to a vessel that can travel underwater. The term is a contraction of submarine boat . and occurs as such in several languages, e.g. French ( sous-marin ), and Spanish ( submarino ), although others retain the original term, such as Dutch ( Onderzeeboot ), German ( Unterseeboot ), Swedish ( Undervattensbåt ), and Russian ( подводная лодка : podvodnaya lodka ), all of which mean 'submarine boat'. By naval tradition , submarines are usually referred to as boats rather than as ships , regardless of their size. Although referred to informally as boats , U.S. submarines employ

585-451: A pivotal time in submarine development, and several important technologies appeared. A number of nations built and used submarines. Diesel electric propulsion became the dominant power system and equipment such as the periscope became standardized. Countries conducted many experiments on effective tactics and weapons for submarines, which led to their large impact in World War I . The first submarine not relying on human power for propulsion

650-415: A separate shed on the tower top. Later, the single light was replaced by a pair of small ( fifth-order ) revolving dioptric optics, each of which produced a single flash every 10 seconds; they were mounted in small turrets on opposite sides of the tower: one shone red towards the north-west, the other shone white towards the south-east (their arcs overlapped, so that vessels approaching from seaward would see

715-847: A single torpedo , in 1885. A reliable means of propulsion for the submerged vessel was only made possible in the 1880s with the advent of the necessary electric battery technology. The first electrically powered boats were built by Isaac Peral y Caballero in Spain (who built Peral ), Dupuy de Lôme (who built Gymnote ) and Gustave Zédé (who built Sirène ) in France, and James Franklin Waddington (who built Porpoise ) in England. Peral's design featured torpedoes and other systems that later became standard in submarines. Commissioned in June 1900,

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780-531: A spar as a torpedo charge. The Hunley also sank. The explosion's shock waves may have killed its crew instantly, preventing them from pumping the bilge or propelling the submarine. In 1866, Sub Marine Explorer was the first submarine to successfully dive, cruise underwater, and resurface under the crew's control. The design by German American Julius H. Kroehl (in German, Kröhl ) incorporated elements that are still used in modern submarines. In 1866, Flach

845-447: A submarine lies in its ability to remain concealed in the depths of the ocean. Early submarines could be detected by the sound they made. Water is an excellent conductor of sound (much better than air), and submarines can detect and track comparatively noisy surface ships from long distances. Modern submarines are built with an emphasis on stealth . Advanced propeller designs, extensive sound-reducing insulation, and special machinery help

910-422: A submarine remain as quiet as ambient ocean noise, making them difficult to detect. It takes specialized technology to find and attack modern submarines. Active sonar uses the reflection of sound emitted from the search equipment to detect submarines. It has been used since WWII by surface ships, submarines and aircraft (via dropped buoys and helicopter "dipping" arrays), but it reveals the emitter's position, and

975-550: A successful firing solution against a three-dimensionally maneuvering target using techniques which became the basis of modern torpedo computer targeting systems. Seventy-four British submarines were lost, the majority, forty-two, in the Mediterranean. The first launch of a cruise missile ( SSM-N-8 Regulus ) from a submarine occurred in July 1953, from the deck of USS  Tunny , a World War II fleet boat modified to carry

1040-691: A test dive while at its operational limit, and USS  Scorpion due to unknown causes. During the Indo-Pakistani War of 1971 , the Pakistan Navy 's Hangor sank the Indian frigate INS  Khukri . This was the first sinking by a submarine since World War II. During the same war, Ghazi , a Tench -class submarine on loan to Pakistan from the US, was sunk by the Indian Navy . It

1105-535: A total of 74 submarines, though of mixed effectiveness. In August 1914, a flotilla of ten U-boats sailed from their base in Heligoland to attack Royal Navy warships in the North Sea in the first submarine war patrol in history. The U-boats' ability to function as practical war machines relied on new tactics, their numbers, and submarine technologies such as combination diesel–electric power system developed in

1170-567: A wide range of types and capabilities. They range from small, autonomous examples, such as one- or two-person subs that operate for a few hours, to vessels that can remain submerged for six months, such as the Russian Typhoon class , (the biggest submarines ever built). Submarines can work at depths that are greater than what is practicable (or even survivable) for human divers . The word submarine means 'underwater' or 'under-sea' (as in submarine canyon , submarine pipeline ) though as

1235-910: Is also sometimes used historically or informally to refer to remotely operated vehicles and robots , or to medium-sized or smaller vessels (such as the midget submarine and the wet sub ). Submarines are referred to as boats rather than ships regardless of their size. Although experimental submarines had been built earlier, submarine design took off during the 19th century, and submarines were adopted by several navies. They were first used widely during World War I (1914–1918), and are now used in many navies , large and small. Their military uses include: attacking enemy surface ships (merchant and military) or other submarines; aircraft carrier protection; blockade running ; nuclear deterrence ; stealth operations in denied areas when gathering intelligence and doing reconnaissance ; denying or influencing enemy movements; conventional land attacks (for example, launching

1300-437: Is now on display at Hurst Castle , together with the old rotating beacon. In addition, a pair of rotating 4th-order dioptric optics, which were in use on the tower prior to automation, are also displayed at the castle. Submarine A submarine (or sub ) is a watercraft capable of independent operation underwater. (It differs from a submersible , which has more limited underwater capability.) The term “submarine”

1365-528: Is susceptible to counter-measures. A concealed military submarine is a real threat, and because of its stealth, can force an enemy navy to waste resources searching large areas of ocean and protecting ships against attack. This advantage was vividly demonstrated in the 1982 Falklands War when the British nuclear-powered submarine HMS  Conqueror sank the Argentine cruiser General Belgrano . After

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1430-475: The Gato , Balao , and Tench classes were commissioned during the war. During the war, 52 US submarines were lost to all causes, with 48 directly due to hostilities. US submarines sank 1,560 enemy vessels, a total tonnage of 5.3 million tons (55% of the total sunk). The Royal Navy Submarine Service was used primarily in the classic Axis blockade . Its major operating areas were around Norway, in

1495-519: The Holland Torpedo Boat Company from 1901 to 1903. Construction of the boats took longer than anticipated, with the first only ready for a diving trial at sea on 6 April 1902. Although the design had been purchased entirely from the US company, the actual design used was an untested improvement to the original Holland design using a new 180 horsepower (130 kW) petrol engine. These types of submarines were first used during

1560-655: The Mediterranean (against the Axis supply routes to North Africa), and in the Far East. In that war, British submarines sank 2 million tons of enemy shipping and 57 major warships, the latter including 35 submarines. Among these is the only documented instance of a submarine sinking another submarine while both were submerged. This occurred when HMS  Venturer engaged U-864 ; the Venturer crew manually computed

1625-538: The Russo-Japanese War of 1904–05. Due to the blockade at Port Arthur , the Russians sent their submarines to Vladivostok , where by 1 January 1905 there were seven boats, enough to create the world's first "operational submarine fleet". The new submarine fleet began patrols on 14 February, usually lasting for about 24 hours each. The first confrontation with Japanese warships occurred on 29 April 1905 when

1690-587: The Straits of Dover to protect allied merchant shipping from German U-boats . Designed by civilian Guy Maunsell , the towers were to be linked together with steel nets and armed with two 4-inch guns with the idea of closing the English Channel to enemy ships. However, by the end of the war in 1918 only one such tower had been completed, at the then-cost of one million pounds, and was located at Shoreham Harbour, awaiting deployment. While another part-built tower would eventually be dismantled in 1924, there remained

1755-521: The bathyscaphe , which evolved from the diving bell . Most large submarines consist of a cylindrical body with hemispherical (or conical) ends and a vertical structure, usually located amidships, which houses communications and sensing devices as well as periscopes . In modern submarines, this structure is called the " sail " in American usage and "fin" in European usage. A feature of earlier designs

1820-658: The British, when they reconsidered Fulton's submarine design. In 1850, Wilhelm Bauer 's Brandtaucher was built in Germany. It remains the oldest known surviving submarine in the world. In 1864, late in the American Civil War , the Confederate navy 's H. L. Hunley became the first military submarine to sink an enemy vessel, the Union sloop-of-war USS  Housatonic , using a gun-powder-filled keg on

1885-511: The English clergyman and inventor George Garrett and the Swedish industrialist Thorsten Nordenfelt led to the first practical steam-powered submarines, armed with torpedoes and ready for military use. The first was Nordenfelt I , a 56-tonne, 19.5-metre (64 ft) vessel similar to Garrett's ill-fated Resurgam (1879), with a range of 240 kilometres (130 nmi; 150 mi), armed with

1950-603: The French steam and electric Narval employed the now typical double-hull design, with a pressure hull inside the outer shell. These 200-ton ships had a range of over 160 km (100 mi) underwater. The French submarine Aigrette in 1904 further improved the concept by using a diesel rather than a gasoline engine for surface power. Large numbers of these submarines were built, with seventy-six completed before 1914. The Royal Navy commissioned five Holland-class submarines from Vickers , Barrow-in-Furness , under licence from

2015-750: The German developments in submarine technology with the creation of the K-class submarines . However, these submarines were notoriously dangerous to operate due to their various design flaws and poor maneuverability. During World War II , Germany used submarines to devastating effect in the Battle of the Atlantic , where it attempted to cut Britain's supply routes by sinking more merchant ships than Britain could replace. These merchant ships were vital to supply Britain's population with food, industry with raw material, and armed forces with fuel and armaments. Although

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2080-798: The Pacific War destroyed more Japanese shipping than all other weapons combined. This feat was considerably aided by the Imperial Japanese Navy's failure to provide adequate escort forces for the nation's merchant fleet. During World War II, 314 submarines served in the US Navy, of which nearly 260 were deployed to the Pacific. When the Japanese attacked Hawaii in December 1941, 111 boats were in commission; 203 submarines from

2145-468: The Pacific in World War II. Mine -laying submarines were developed in the early part of the 20th century. The facility was used in both World Wars. Submarines were also used for inserting and removing covert agents and military forces in special operations , for intelligence gathering, and to rescue aircrew during air attacks on islands, where the airmen would be told of safe places to crash-land so

2210-583: The Russian submarine Som was fired upon by Japanese torpedo boats, but then withdrew. Military submarines first made a significant impact in World War I . Forces such as the U-boats of Germany saw action in the First Battle of the Atlantic , and were responsible for sinking RMS  Lusitania , which was sunk as a result of unrestricted submarine warfare and is often cited among the reasons for

2275-502: The Solent approach, and actually shot down several aircraft. The Royal Navy withdrew its personnel from the tower some time after the war, but the tower remained under Ministry of Defence ownership until 1984, when Trinity House acquired the freehold (they had previously taken over responsibility for the light itself from the Admiralty in 1929). The Nab Tower still functions as a lighthouse, but since 1983 it has been unmanned. That year,

2340-621: The U-boats had been updated in the interwar years, the major innovation was improved communications, encrypted using the Enigma cipher machine . This allowed for mass-attack naval tactics ( Rudeltaktik , commonly known as " wolfpack "), which ultimately ceased to be effective when the U-boat's Enigma was cracked . By the end of the war, almost 3,000 Allied ships (175 warships, 2,825 merchantmen) had been sunk by U-boats. Although successful early in

2405-806: The US, the Soviet Union (now Russia), the UK, and France have been powered by a nuclear reactor . In 1959–1960, the first ballistic missile submarines were put into service by both the United States ( George Washington class ) and the Soviet Union ( Golf class ) as part of the Cold War nuclear deterrent strategy. During the Cold War, the US and the Soviet Union maintained large submarine fleets that engaged in cat-and-mouse games. The Soviet Union lost at least four submarines during this period: K-129

2470-659: The belief that the vessel was evacuating anti-Israeli militias. The ship was hit by two torpedoes, managed to run aground but eventually sank. There were 25 dead, including her captain. The Israeli Navy disclosed the incident in November 2018. Before and during World War II , the primary role of the submarine was anti-surface ship warfare. Submarines would attack either on the surface using deck guns, or submerged using torpedoes . They were particularly effective in sinking Allied transatlantic shipping in both World Wars, and in disrupting Japanese supply routes and naval operations in

2535-402: The completed 92-foot-tall (28 m) metal cylinder sitting on a raft of concrete. In 1920 the completed tower was towed by two paddle-wheel tugs to the Nab rock, a rock in the deep-water approach to the eastern Solent and previously marked by a lightship . Buoyancy was provided by the honeycomb construction of the concrete base, creating 18 watertight compartments. When these were flooded,

2600-463: The craft. A mechanism was used to twist the water out of the bags and cause the boat to resurface. In 1749, the Gentlemen's Magazine reported that a similar design had initially been proposed by Giovanni Borelli in 1680. Further design improvement stagnated for over a century, until application of new technologies for propulsion and stability. The first military submersible was Turtle (1775),

2665-437: The delay between receiving the radio signal and the audible signal, vessels were able to calculate their distance from the tower. The tower was equipped with a fog bell , as well as the diaphone, which sounded one stroke every 7.5 seconds. The Nab Tower was manned as a lighthouse, but also functioned as a Royal Navy signal station ; and during World War II it was equipped with a pair of Bofors guns to provide some defence to

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2730-571: The designation USS ( United States Ship ) at the beginning of their names, such as USS  Alabama . In the Royal Navy, the designation HMS can refer to "His Majesty's Ship" or "His Majesty's Submarine", though the latter is sometimes rendered "HMS/m" and submarines are generally referred to as boats rather than ships . According to a report in Opusculum Taisnieri published in 1562: Two Greeks submerged and surfaced in

2795-441: The development of the homing torpedo, better sonar systems, and nuclear propulsion , submarines also became able to hunt each other effectively. The development of submarine-launched ballistic missile and submarine-launched cruise missiles gave submarines a substantial and long-ranged ability to attack both land and sea targets with a variety of weapons ranging from cluster bombs to nuclear weapons . The primary defense of

2860-677: The enemyes by the Grace of God and worke of expert Craftsmen I hope to perform." It is unclear whether he carried out his idea. Jerónimo de Ayanz y Beaumont (1553–1613) created detailed designs for two types of air-renovated submersible vehicles. They were equipped with oars, autonomous floating snorkels worked by inner pumps, portholes and gloves used for the crew to manipulate underwater objects. Ayanaz planned to use them for warfare, using them to approach enemy ships undetected and set up timed gunpowder charges on their hulls. The first submersible of whose construction there exists reliable information

2925-402: The entry of the United States into the war. At the outbreak of the war, Germany had only twenty submarines available for combat, although these included vessels of the diesel-engined U-19 class, which had a sufficient range of 5,000 miles (8,000 km) and speed of 8 knots (15 km/h) to allow them to operate effectively around the entire British coast., By contrast, the Royal Navy had

2990-550: The first practical self-propelled or "locomotive" torpedo. The spar torpedo that had been developed earlier by the Confederate States Navy was considered to be impracticable, as it was believed to have sunk both its intended target, and H. L. Hunley , the submarine that deployed it. The Irish inventor John Philip Holland built a model submarine in 1876 and in 1878 demonstrated the Holland I prototype. This

3055-521: The highest submerged speeds during World War II ( I-201 -class submarines) and submarines that could carry multiple aircraft ( I-400 -class submarines). They were also equipped with one of the most advanced torpedoes of the conflict, the oxygen-propelled Type 95 . Nevertheless, despite their technical prowess, Japan chose to use its submarines for fleet warfare, and consequently were relatively unsuccessful, as warships were fast, maneuverable and well-defended compared to merchant ships. The submarine force

3120-435: The missile with a nuclear warhead . Tunny and its sister boat, Barbero , were the United States' first nuclear deterrent patrol submarines. In the 1950s, nuclear power partially replaced diesel–electric propulsion. Equipment was also developed to extract oxygen from sea water. These two innovations gave submarines the ability to remain submerged for weeks or months. Most of the naval submarines built since that time in

3185-405: The preceding years. More submersibles than true submarines, U-boats operated primarily on the surface using regular engines, submerging occasionally to attack under battery power. They were roughly triangular in cross-section, with a distinct keel to control rolling while surfaced, and a distinct bow. During World War I more than 5,000 Allied ships were sunk by U-boats. The British responded to

3250-408: The red light as well as the white if their course took them too close to St Catherine's Point , approaching from the west, or Selsey Bill , approaching from the east). In December 1935 a radio beacon was added. In 1938 a more powerful diaphone fog signal was installed (in place of the old fog horn), which gave one 2.5-second blast every minute. It was synchronised with the radio beacon; by timing

3315-694: The river Tagus near the City of Toledo several times in the presence of The Holy Roman Emperor Charles V , without getting wet and with the flame they carried in their hands still alight. In 1578, the English mathematician William Bourne recorded in his book Inventions or Devises one of the first plans for an underwater navigation vehicle. A few years later the Scottish mathematician and theologian John Napier wrote in his Secret Inventions (1596) that "These inventions besides devises of sayling under water with divers, other devises and strategems for harming of

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3380-631: The sinking the Argentine Navy recognized that they had no effective defense against submarine attack, and the Argentine surface fleet withdrew to port for the remainder of the war. An Argentine submarine remained at sea, however. Although the majority of the world's submarines are military, there are some civilian submarines, which are used for tourism, exploration, oil and gas platform inspections, and pipeline surveys. Some are also used in illegal activities. The Submarine Voyage ride opened at Disneyland in 1959, but although it ran under water it

3445-399: The structure sank and settled to rest at an angle of 3 degrees from vertical towards the northeast – a characteristic tilt which is obvious to this day. Initially, the tower had a single centrally-placed lamp containing an Osram gas-filled incandescent light bulb , which gave a single white flash every ten seconds, with a visible range of 16 nautical miles. A fog horn was also installed, in

3510-476: The submarines could rescue them. Submarines could carry cargo through hostile waters or act as supply vessels for other submarines. Submarines could usually locate and attack other submarines only on the surface, although HMS  Venturer managed to sink U-864 with a four torpedo spread while both were submerged. The British developed a specialized anti-submarine submarine in WWI, the R class . After WWII, with

3575-466: The war, Germany's U-boat fleet suffered heavy casualties, losing 793 U-boats and about 28,000 submariners out of 41,000, a casualty rate of about 70%. The Imperial Japanese Navy operated the most varied fleet of submarines of any navy, including Kaiten crewed torpedoes, midget submarines ( Type A Ko-hyoteki and Kairyu classes ), medium-range submarines, purpose-built supply submarines and long-range fleet submarines . They also had submarines with

3640-633: Was built at the Chilean government's request by Karl Flach , a German engineer and immigrant. It was the fifth submarine built in the world and, along with a second submarine, was intended to defend the port of Valparaiso against attack by the Spanish Navy during the Chincha Islands War . Submarines could not be put into widespread or routine service use by navies until suitable engines were developed. The era from 1863 to 1904 marked

3705-461: Was coated in a new layer of gun-applied concrete. On completion, new AIS and RACON beacons were fitted, along with a fixed main LED light (and identical standby light) with a 12 nautical mile range; a new fog signal was also installed, sounding two blasts every 30 seconds (altered to one blast in 2022). All are solar powered. The distinctive red lantern structure, removed as part of the refurbishment,

3770-440: Was designed and built in 1620 by Cornelis Drebbel , a Dutchman in the service of James I of England . It was propelled by means of oars. By the mid-18th century, over a dozen patents for submarines/submersible boats had been granted in England. In 1747, Nathaniel Symons patented and built the first known working example of the use of a ballast tank for submersion. His design used leather bags that could fill with water to submerge

3835-720: Was followed by a number of unsuccessful designs. In 1896, he designed the Holland Type VI submarine, which used internal combustion engine power on the surface and electric battery power underwater. Launched on 17 May 1897 at Navy Lt. Lewis Nixon 's Crescent Shipyard in Elizabeth, New Jersey , Holland VI was purchased by the United States Navy on 11 April 1900, becoming the Navy's first commissioned submarine, christened USS  Holland . Discussions between

3900-734: Was lost in 1968 (a part of which the CIA retrieved from the ocean floor with the Howard Hughes -designed ship Glomar Explorer ), K-8 in 1970, K-219 in 1986, and Komsomolets in 1989 (which held a depth record among military submarines—1,000 m (3,300 ft)). Many other Soviet subs, such as K-19 (the first Soviet nuclear submarine, and the first Soviet sub to reach the North Pole) were badly damaged by fire or radiation leaks. The US lost two nuclear submarines during this time: USS  Thresher due to equipment failure during

3965-443: Was not a true submarine, as it ran on tracks and was open to the atmosphere. The first tourist submarine was Auguste Piccard , which went into service in 1964 at Expo64 . By 1997, there were 45 tourist submarines operating around the world. Submarines with a crush depth in the range of 400–500 feet (120–150 m) are operated in several areas worldwide, typically with bottom depths around 100 to 120 feet (30 to 37 m), with

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4030-488: Was the " conning tower ": a separate pressure hull above the main body of the boat that enabled the use of shorter periscopes. There is a propeller (or pump jet) at the rear, and various hydrodynamic control fins. Smaller, deep-diving, and specialty submarines may deviate significantly from this traditional design. Submarines dive and resurface by using diving planes and by changing the amount of water and air in ballast tanks to affect their buoyancy . Submarines encompass

4095-614: Was the French Plongeur ( Diver ), launched in 1863, which used compressed air at 1,200  kPa (180  psi ). Narcís Monturiol designed the first air-independent and combustion -powered submarine, Ictíneo II , which was launched in Barcelona , Spain in 1864. The submarine became feasible as potential weapon with the development of the Whitehead torpedo , designed in 1866 by British engineer Robert Whitehead ,

4160-626: Was the first submarine combat loss since World War II. In 1982 during the Falklands War , the Argentine cruiser General Belgrano was sunk by the British submarine HMS  Conqueror , the first sinking by a nuclear-powered submarine in war. Some weeks later, on 16 June, during the Lebanon War , an unnamed Israeli submarine torpedoed and sank the Lebanese coaster Transit , which was carrying 56 Palestinian refugees to Cyprus , in

4225-476: Was the most effective anti-ship weapon in the American arsenal. Submarines, though only about 2 percent of the U.S. Navy, destroyed over 30 percent of the Japanese Navy, including 8 aircraft carriers, 1 battleship and 11 cruisers. US submarines also destroyed over 60 percent of the Japanese merchant fleet, crippling Japan's ability to supply its military forces and industrial war effort. Allied submarines in

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