Torpedo 31424 224604574 2008-07-09T16:51:51Z Ch1n4m4n 7298569 /* Warhead/fuzing */ {{this|the self-propelled weapon|torpedo (disambiguation)}} The modern '''torpedo''' (historically called an automotive, automobile, locomotive, or fish torpedo) is a self-propelled explosive [[projectile]] weapon, launched above or below the water surface, propelled underwater toward a target, and designed to detonate on contact or in proximity to a target. The original use of "torpedo" was for a variety of devices that would today be mostly called a "[[naval mine|mine]]". However, from the First World War onwards "torpedo" was only used for an underwater self-propelled missile, often called colloquially a "fish". Today's torpedoes can be divided into lightweight and heavyweight classes, and into straight running, autonomous homers and wire-guided ones. They can be launched from a variety of platforms. Originally, the torpedo was primarily used in an anti-shipping role. This has been largely superseded by the missile, so the torpedo's main contemporary use is against [[submarine]]s.{{Fact|date=May 2008}} == Launch platforms == [[Image:USN MK-46 Mod 5 lightweight torpedo.jpg|thumb|300px|A Mark 32 Mod 15 Surface Vessel [[Torpedo Tube]] (SVTT) fires a [[Mk 46 torpedo|Mark 46 Mod 5 lightweight torpedo]].]] Torpedoes may be launched from submarines, surface ships, [[helicopter]]s and fixed-wing [[aircraft]], unmanned [[naval mine]]s and naval [[fortress]]es. They are also used in conjunction with other weapons; for example the [[Mark 46]] torpedo used by the [[United States]] becomes the warhead section of the [[ASROC]] (Anti-Submarine [[rocket|ROCket]]) and the [[CAPTOR mine]] (CAPsulated TORpedo) is a submerged sensor platform which releases a torpedo when a hostile contact is detected. While the battleship had evolved primarily around engagements between armoured ships with large guns, the torpedo allowed [[torpedo boat]]s, other lighter surface ships, submersibles, and aircraft to destroy large ships without large-caliber guns, though sometimes at the risk of being hit by longer-range shellfire. In the [[Battle of Samar]], destroyer-mounted torpedoes were the only weapons available to the U.S. task force capable of damaging opposing Japanese cruisers and battleships. ==Etymology== The word ''torpedo'' comes from a genus of [[electric ray]]s in the order ''[[Torpediniformes]]'', which in turn comes from the [[Latin]] "torpere" (to stun). In naval usage, the torpedo was so named by [[Robert Fulton]], who used it to refer to a towed gunpowder charge used by his [[submarine]] [[Nautilus (1800 submarine)|''Nautilus'']] to demonstrate it could sink warships. ==History== Prior to the invention of the self-propelled torpedo, the term was applied to any number of different types of explosive devices, generally having the property of being secret or hidden, including devices which today would include [[booby trap]]s, [[land mine]]s, [[naval mine]]s, and others. Much like the invention of the helicopter, the earliest torpedo concepts existed many centuries before being developed as working devices. The earliest known description is found in the work of [[Syria]]n [[Inventions in the Muslim world|engineer]] Hassan al-Rammah in 1275. His works show illustrations of a rocket-propelled device that appears to have been designed to move on the surface of water.<ref name="al-rammah">{{cite web|url=http://muslimheritage.com/topics/default.cfm?ArticleID=284|title=Muslim Rocket Technology|author=Prof. Dr. Mohamed Mansour|publisher=MuslimHeritage.com|date=2002-03-22|accessdate=2007-07-18}}</ref> ===Early naval "torpedoes"=== [[Image:Sinking torpedoes.jpg|right|thumb|300px|Confederates laying torpedoes in Charleston Harbor]] Although the term "torpedo" was not coined until 1800, the early submarine [[Turtle (submarine)|''Turtle'']] attacked using an explosive very similar in intent and function. ''Turtle'' dived under a British vessel to attach a bomb by means of an auger. The bomb was to be detonated by a timed fuse, probably a type of clockwork mechanism. In its only recorded attack, ''Turtle'' failed to penetrate the hull of [[HMS Eagle (1774)|HMS ''Eagle'']], which had been copper-plated to resist [[shipworm]]s. The first usage of the term torpedo to refer to a naval explosive was by American inventor Robert Fulton. In 1800, Fulton launched his submarine, ''Nautilus'', and demonstrated its method of attack using a floating explosive charge Fulton called a torpedo. The submarine would tow the torpedo, submerging beneath an enemy vessel and dragging the torpedo into contact with it. Fulton successfully destroyed demonstration targets in both France and Britain, but neither government was interested in purchasing the vessel and Fulton's experiments ceased in 1805. During the [[American Civil War]], the term torpedo was used for what is today called a [[Naval mine#Contact mines|contact mine]], floating on or below the water surface using an air-filled [[Carboy|demijohn]] or similar flotation device. (As self-propelled torpedoes were developed the tethered variety became known as ''stationary torpedoes'' and later ''mines''.) Several types of naval "torpedo" were developed and deployed, most often by the Confederates, who faced a severe disadvantage in more traditional warfare methods. In this period, "torpedoes" floated freely on the surface or were bottom-moored just below the surface. They were detonated when struck by a ship, or after a set time, but were unreliable. These could be as much a danger to Confederate as to [[Union (American Civil War)|Union]] shipping, and were sometimes marked with flags that could be removed if Union attack was deemed imminent. Rivers mined with Confederate torpedoes were often cleared by Unionists placing captured Confederate soldiers with knowledge of the torpedoes' location in small boats ahead of the main fleet. "Torpedoes" (mines) could also be detonated electrically by an operator on shore (as demonstrated also by Fulton), so friendly vessels or low-value enemy vessels could be ignored while waiting for the capital ships to sail over them. However, the Confederacy was plagued by a chronic shortage of materials including [[platinum]] and copper wire and acid for batteries, and the wires had a tendency to break. Electricity was a new technology, and the limitations of [[direct current]] for effective distance was poorly understood, so failures were also possible because of the decrease in voltage when the torpedoes were placed too far from the batteries. Former [[United States Navy]] Commander [[Matthew Fontaine Maury|Matthew Maury]], who served as a commander in the [[Confederate States Navy|Confederate Navy]], worked on the development of an underwater electrical mine. [[David Farragut]] encountered tethered and floating contact mines in 1864 at the American Civil War [[Battle of Mobile Bay]]. After his leading [[ironclad]], [[USS Tecumseh (1863)|USS ''Tecumseh'']], was sunk by a tethered contact mine (torpedo), his vessels halted, afraid of hitting additional torpedoes. Inspiring his men to push forward, Farragut famously ordered, "''Damn the torpedoes, full speed ahead!''" The first torpedo designed to attack a specific target was the [[spar torpedo]], an explosive device mounted at the end of a spar up to 40 feet (12 m) long projecting forward underwater from the bow of the attacking vessel. When driven up against the enemy and detonated, a hole would be caused below the water line. Spar torpedoes were employed by the Confederate submarine [[H. L. Hunley (submarine)|''H. L. Hunley'']], as well as by [[CSS David|''David'']]-class torpedo boats, among others. However, these torpedoes were liable to cause as much harm to their users as to their targets. ===Bombs and booby traps=== [[Image:Western torpedoes.jpg|right|thumb|Illustration of naval torpedoes moored to the river bottom (the predecessors of modern naval mines)]] During the US Civil War, the term "torpedo" was also used to refer to various types of bombs and [[boobytrap]]s. Confederate General [[Gabriel Rains]] deployed "sub-terra shells" or "land torpedoes", [[artillery]] [[Shell (projectile)|shells]] with [[pressure]] [[Fuse (explosives)|fuses]] buried in the road by retreating Confederate forces to delay their pursuers. These were the forerunners of modern land mines. Union generals publicly deplored this conduct. Confederate secret agent [[John Maxwell]] used a clockwork mechanism to detonate a large "horological torpedo" (time bomb) on [[August 9]], [[1864]]. The bomb was hidden in a box marked "candles" and placed aboard a barge containing Union ammunition (20,000–30,000 artillery shells and 75,000 [[small arms]] rounds) moored at [[City Point, Virginia]], on the [[James River (Virginia)|James River]]. The explosion caused more than [[United States dollar|US$]]2 million in damage and killed at least 43 people. The [[coal torpedo]] was a bomb shaped like a lump of coal, to be hidden in coal piles used for fueling Union naval vessels. The bomb would be shoveled into the firebox along with the real coal, causing an explosion. Although the North referred to the device as the coal torpedo in newspaper articles, the Confederates referred to it as a "coal shell". ===Self-propelled torpedoes=== [[Image:Ottoman submarine Abdulhamid 1886.jpg|thumb|left|[[Thorsten Nordenfelt|Nordenfelt]]-class Ottoman [[submarine]] ''Abdülhamid'' (1886) was the first submarine in history to fire a torpedo while submerged. Two submarines of this class, ''Abdülhamid'' (1886) and ''Abdülmecid'' (1887) joined the [[Ottoman Empire|Ottoman]] fleet. They were built in pieces by Des Vignes (Chertsey) and [[Vickers]] (Sheffield) in [[England]], and assembled at the Taşkızak Naval Shipyard in [[Istanbul]], [[Turkey]].]] [[Image:Argonaute FS S636 p1040842 boosted colors.jpg|thumb|left|The torpedo room of ''[[Argonaute (S636)|Argonaute]]'', a [[Cold War]]-era [[France|French]] [[Diesel]] [[submarine]].]] From [[World War I]] onwards, the word ''torpedo'' was used only for self-propelled projectiles that travelled under or on water. The first working prototype of the modern self-propelled torpedo was created by a commission placed by [[Giovanni Luppis]] (Ivan Lupis), an [[Austro-Hungarian Navy|Austrian naval officer]] from [[Fiume]] (today [[Rijeka]], [[Croatia]]), a port city of the [[Austrian Empire]], on [[Robert Whitehead]], an [[United Kingdom|English]] engineer who was the manager of a Fiume factory. In 1864, Luppis presented Whitehead with the plans of the ''salvacoste'' (coastsaver), a floating weapon, driven by ropes from the land, and made a contract with him in order to perfect the invention. Whitehead was unable to improve the machine substantially, since the clockwork motor, the attached ropes and the surface attack mode all contributed to a slow and cumbersome weapon. However, he kept considering the problem after the contract had finished, and eventually developed a tubular device, designed to run underwater on its own, and powered by compressed air. The result was a submarine weapon, the ''Minenschiff'' (mine ship), the first real self-propelled torpedo, officially presented to the Austrian Imperial Naval commission on [[December 21]], [[1866]]. Maintaining proper depth was a major problem in the early days but Whitehead introduced his "secret" in 1868 which overcame this. It was a mechanism consisting of a [[Pendulum and Hydrostat Control|hydrostatic valve and pendulum]] which caused the torpedo's hydroplanes to be adjusted so as to maintain a preset depth. After the Austrian government decided to invest in the invention, Whitehead started the first torpedo factory in Fiume. In 1870, they improved the devices to travel up to approximately 1000 yards (914 m) at a speed of up to six [[knot (nautical)|knot]]s, and by 1881 the factory was exporting its torpedoes to ten other countries. The torpedo was powered by compressed air and had an explosive charge of [[gloxyline]] ([[gun-cotton]]). Whitehead went on to develop more efficient devices, demonstrating torpedoes capable of 18 knots (1876), 24 knots (1886), and finally 30 knots (1890). [[Royal Navy]] representatives visited Fiume to see a demonstration in late 1869 and in 1870 a batch of torpedoes was ordered. In 1871, the British [[Admiralty]] paid him [[Pound sterling|£]]15,000 for certain of his developments and production started at the Royal Laboratories in Woolwich the following year. In 1893, RN torpedo production was transferred to the Royal Gun Factory. The British later established a Torpedo Experimental Establishment at [[HMS Vernon|HMS ''Vernon'']] and a production facility at the Royal Naval Torpedo Factory, Greenock in 1910. These are now closed. Whitehead opened a new factory near [[Portland harbour]], [[England]] in 1890, which continued making torpedoes until the end of the Second World War. Because orders from the RN were not as large as expected, torpedoes were mostly exported. A series of devices was produced at Fiume, from 14" upward. The largest Whitehead torpedo was 18 inches (457 mm) in diameter and 19 feet (5.8 m) long, made of polished steel or phosphor-bronze, with a 200 lb (90 kg) gun-cotton warhead. It was propelled by two propellers driven by a three-cylinder Brotherhood engine, using compressed air at around 1300 lbf/in² (9 MPa). The torpedo was designed to self-regulate its course and depth as far as possible. By 1881, nearly 1500 torpedoes had been produced. Whitehead also opened a factory at St Tropez in 1890 which exported torpedoes to Brazil, Holland, Turkey and Greece. Whitehead faced competition from the American [[Lieutenant Commander]] [[John Adams Howell|John A. Howell]], whose [[Howell torpedo|own design]], driven by [[flywheel]], was simpler and cheaper. It was produced from 1885 to 1895, and left no wake and ran straight. A Torpedo Test Station had been set up on Rhode Island in 1870, and an automobile torpedo produced in 1871 but this was unsuccessful. The Lay torpedoes were also largely unsuccessful as were various privately invented ones. The Howell torpedo was the only USN one until Whitehead torpedoes produced by Bliss and Williams (later E W Bliss and Co) came into service in 1894. Five varieties were produced, all 45 cm diameter. An improved version, the [[Bliss-Leavitt]],with a turbine engine was later produced, some with a larger diameter. Various versions were used in both World War I and World War II. Whitehead purchased rights to the [[gyroscope]] of Ludwig Obry in 1888 but it was not sufficiently accurate, so in 1890 he purchased a better design (ironically from Howell) to improve control of his designs, which came to be called the "Devil's Device". The firm of [[Schwartzkopf (torpedo)|L. Schwartzkopf]] in Germany also produced torpedoes and exported them to Russia, Japan, and Spain. In 1885, Britain ordered a batch of 50 as torpedo production at home and at Fiume could not meet demand. On [[16 January]] [[1878]], the [[Turkey|Turkish]] steamer ''Intibah'' became the first vessel to be sunk by self-propelled torpedoes, launched from torpedo boats operating from the tender [[Russian tender Velikiy Knyaz Konstantin|''Velikiy Knyaz Konstantin'']] under the command of [[Stepan Osipovich Makarov]] during the [[Russo-Turkish War, 1877-78|Russo-Turkish War of 1877-78]]. In another early use of the torpedo, ''[[Blanco Encalada]]'' was sunk on [[April 23]] [[1891]] by a torpedo from the gunboat ''[[Almirante Lynch]]'', during the [[Chilean Civil War]]. By this time the [[torpedo boat]], the first of which had been built at the shipyards of Sir [[John Isaac Thornycroft|John Thornycroft]] in 1877, had gained recognition for its effectiveness, and the first [[destroyer|torpedo boat destroyer]]s (later simply destroyers) were built to counter it. Torpedoes were also used to equip [[gunboat]]s of around 1,000 tons, thus becoming [[torpedo gunboat]]s. Originally, torpedoes were designed to be straight running, though this was not always the case in practice. Around 1897, [[Nikola Tesla]] patented a [[remote control]]led boat and later demonstrated the feasibility of radio-guided torpedoes to the [[United States]] military. Torpedoes were widely used in the First World War, both against shipping and against submarines. Germany and its allies disrupted the supply lines to Britain largely by use of submarine torpedoes (though submarines also extensively used guns).<ref>The war's top ace used them exclusively, and stuck religiously to the "cruiser rules".</ref>) Britain and its allies also used torpedoes throughout the war. U-boats themselves were often targeted, twenty being sunk by torpedo. Originally the Japanese Navy purchased Whitehead or Schwartzkopf torpedoes but by 1917 they were conducting experiments with oxygen as a fuel. Because of explosions they abandoned the experiments but resumed them in 1926 and by 1933 had a working torpedo. They also used conventional wet-heater torpedoes. In the inter-war years, tight budgets caused nearly all navies to skimp on testing their torpedoes. As a result, only the Japanese had fully-tested torpedoes (in particular the [[Type 93 torpedo|Type 93]]) at the start of [[World War II]]. The lack of reliability caused major problems for the American Submarine Force in the initial years of the American involvement in [[World War II]], primarily in the [[Pacific War]]. All classes of ship, including submarines, and aircraft were armed with torpedoes. Naval strategy at the time was to use torpedoes, launched from submarines or warships, against enemy warships in a fleet action on the high seas. Targeting unarmed enemy merchant shipping was prohibited by [[Laws of war|rules of war]]. (In the event, merchantmen were armed and acted as ''de facto'' naval auxiliaries, rendering the distinction moot.) There was concern torpedoes would be ineffective against warships' heavy armor; an answer to this was to detonate torpedoes underneath a ship, breaking its back. This was demonstrated by [[magnetic influence mine]]s in [[World War I]]. The torpedo is set to run beneath the ship, and the magnetic exploder to activate at the correct time. Germany, Britain, and the U.S. independently devised ways to do this; German and American torpedoes, however, suffered problems with their depth-keeping mechanisms, coupled with faults in [[magnetic pistol]]s shared by all designs. Inadequate testing had failed to reveal the effect of the earth's magnetic field on ships and exploder mechanisms, which resulted in premature detonation. The ''[[Kriegsmarine]]'' and [[Royal Navy]] promptly identified and eliminated the problems. In the [[United States Navy]], there was an extended wrangle over the problems plaguing the [[Mark 14 torpedo]] (and its [[Mark 6 exploder]]). Cursory trials had allowed bad designs to enter service. Both the Navy [[Bureau of Ordnance]] and the [[United States Congress]] were too busy protecting their own interests to correct the errors; fully-functioning torpedoes only became available to the USN twenty-one months into the Pacific War.<ref>Blair, p.20</ref> British submarines used torpedoes to interdict the Axis supply shipping to North Africa and the [[Fleet Air Arm]] [[Fairey Swordfish|Swordfish]] sank three Italian battleships at Taranto by torpedo. Torpedoes were used by British surface vessels to help finish off the German battleship [[German battleship Bismarck|Bismarck]]. Large tonnages of merchant shipping were sunk by U-boats with torpedoes; as in World War One, the Germans also made extensive use of deck guns. Later in the Second World War, torpedoes were given acoustic (homing) [[guidance system]]s, originally by the Germans in the [[G7es torpedo]], and they were a significant factor in the Allied victory in the [[Battle of the Atlantic]]{{Fact|date=March 2008}}. Pattern-following and wake homing torpedoes were also developed. Acoustic homing formed the basis for torpedo guidance after the Second World War. Though Lupis' original design had been rope guided, torpedoes were not wireguided until the 1960s. Because of improved submarine strength and speed, torpedoes had to be given improved warheads and better motors. During the Cold War, torpedoes were an important asset with the advent of nuclear powered submarines, which did not have to surface often, particularly those carrying strategic nuclear missiles. ==Energy sources== [[Image:USS Mustin (DDG-89) torpedo.jpg|thumb|right|220px|The [[USS Mustin (DDG-89)]] launches a dud torpedo during exercises]] ===Compressed air=== This first successful self-propelled Whitehead torpedo of 1866 used [[Pneumatics|compressed air]] as its energy source. The air was stored at pressures of up to 2.55 [[Pascal (unit)|MPa]] and fed to a [[piston engine]] which turned a single [[propeller]] at about 100 [[Revolutions per minute|rpm]]. It was able to travel about 180 m (200yd) at an average speed of 6.5 [[knot (speed)|knots]] (12 km/h). The speed and range of later models was enhanced by increasing the pressure of the stored air. In 1906 Whitehead built torpedoes which were able to travel nearly 1000 m (1100yd) at an average speed of 35kt (64 km/h). At higher pressures the cooling experienced by the air as it expanded in the engine caused icing problems (see [[Adiabatic process#Adiabatic heating and cooling|adiabatic cooling]]). This was remedied by heating the air with seawater before it was fed to the engine, which increased engine performance further, because the air expanded even more after heating. This was the principle used by the Brotherhood engine. ===Heated torpedoes=== This led to the idea of injecting a liquid fuel, like [[kerosene]], into the air and igniting it. In this manner the air is heated up more and expands even further, and the burned propellant adds more gas to drive the engine. Construction of such ''heated'' torpedoes started around 1904 by Whitehead's company. ===Wet-heater=== A further enhancement was the use of water to cool the [[combustion chamber]]. This not only solved heating problems so more fuel could be burnt, but also allowed additional power to be generated by feeding the resulting steam into the engine together with the [[combustion]] products. Torpedoes with such a propulsion system became known as ''wet heaters'', while heated torpedoes without steam generation were, retrospectively, called ''dry heaters''. A simpler system was introduced by the British Royal Gun factory in 1908. Most torpedoes used in World War I and World War II were wet-heaters. ===Compressed oxygen=== The amount of fuel that can be burnt by a torpedo engine is limited by the amount of [[oxygen]] it can carry. Since compressed air contains only about [[Earth's atmosphere|21%]] of oxygen, engineers in [[Japan]] developed the [[Type 93 torpedo|Type 93]] (nicknamed ''Long Lance'' postwar by historian [[Samuel E. Morison]]) for destroyers in the 1930s. The Type 93 used pure oxygen instead of compressed air and had unmatched performance in World War II. During the war, Germany experimented with hydrogen peroxide for the same purpose. === Steam === [[Image:TorpedoMotor.JPG|right|thumb|US World War II Torpedo belonging to PT-658 in Portland, OR]] A derivative of the compressed-air torpedo was the steam torpedo. Developed by [[Vickers Ltd]], it mixed [[alcohol]] (first [[ethanol]], later [[methanol]]) with compressed air in the combustion chamber, producing steam. This increased speed, but produced a visible [[wake]].<ref>Blair, p.30-1.</ref> ===Wire driven=== The [[Brennan torpedo]] had two wires wound around drums inside the torpedo. A shore based steam [[winch]] pulled the wires, which spun the drums and drove the propeller. Such systems were used for [[coastal defence]] of the British homeland and colonies from 1887 to 1903. Speed was about {{convert|25|kn|km/h|0}} for over 2,400 m. ===Flywheel=== The [[Howell torpedo]] used by the [[US Navy]] in the late 1800s featured a heavy [[flywheel]] which had to be spun up before launch. It was able to travel about 400yd (365 m) at 25 knots (46 km/h). The Howell had the advantage of not leaving a trail of bubbles behind it, unlike compressed air torpedoes. This gave the target vessel less chance to detect and evade the torpedo, and avoided giving away the attacker's position. Additionally, it ran at a constant depth, unlike the very early Whitehead models. ===Electric batteries=== Electric propulsion systems also avoided tell-tale bubbles. [[John Ericsson]] invented an electrically propelled torpedo in 1873; it was powered by a cable from an external power source, as [[Battery (electricity)|batteries]] of the time had insufficient capacity. The Sims-Edison torpedo was similarly powered. The Nordfelt torpedo was also electrically powered and was steered by impulses down a trailing wire. Germany introduced its first battery-powered torpedo shortly before World War II, the [[G7e]]. It was slower and had shorter range than the conventional [[G7a]], but was wakeless and much cheaper. Its [[lead-acid battery|lead-acid]] [[rechargeable battery]] was sensitive to shock, required frequent maintenance before use, and required preheating for best performance. The experimental [[G7ep]], an enhancement of the G7e, used [[primary cell]]s. Modern electric torpedoes such as the [[Mark 24 Tigerfish]] or DM2 series commonly use [[Silver-oxide battery|silver oxide batteries]] which need no maintenance, allowing torpedoes to be stored for years without losing performance. ===Rockets=== A number of experimental rocket propelled torpedoes were tried soon after Whitehead's invention. They were not successful. However rocket propulsion has again recently been used in Russian and German torpedoes (see below). ===Modern drive systems=== Modern torpedoes utilize a variety of drive mechanisms, including gas turbines (the British [[Spearfish torpedo|Spearfish]]), [[monopropellant]]s, and [[sulphur hexafluoride]] gas sprayed over a block of solid [[lithium]]. Some torpedoes, such as the Russian [[VA-111 Shkval]], the Iranian [[Hoot (missile)|Hoot]] or the proposed German Unterwasserlaufkörper / Barracuda <ref name="diehl">[http://www.diehl-bgt-defence.de/index.php?id=550 Diehl BGT: Unterwasserlaufkörper]</ref>, use [[supercavitation]] to increase their speed to over 200 knots (370 km/h); compare the speed of the [[Mark 48 torpedo]], which does not use supercavitation, of about 55 knots (63 mi/h, 101 km/h). ==Propulsion== The first of Whitehead's torpedoes had a single propeller and so needed a large vane to stop it turning in a circle. Not long afterwards the idea of contra-rotating propellers was introduced (at Woolwich), so not requiring the vane. The three bladed propellor came in 1893 and the four bladed one in 1897. To minimise noise, today's torpedoes often use pump jets. == Guidance and tactics == [[Image:Sopwith Cuckoo.jpg|thumb|A torpedo dropped from a [[Sopwith Cuckoo]] during World War I.]] The first guided torpedo was the Victorian era Brennan, which could be steered onto its target by varying the relative speeds of its contra-rotating propellers. However the Brennan required a substantial infrastructure and was not suitable for ship-board use. Therefore, for the first part of its history, the torpedo was guided only in the sense its course could be regulated so as to achieve an intended impact depth (due to the sine wave running path of the Whitehead,<ref>Fitzsimons, Bernard, ed. "Bliss-Leavitt", in ''The Illustrated Encyclopedia of 20th Century Weapons and Warfare'' (London: Phoebus, 1978), Volume 4, p.386.</ref> this was a hit or miss proposition, even when everything worked correctly) and, through gyroscopes, a straight course. With such torpedoes the method of attack in [[Torpedo boats#Small Torpedo Craft|small torpedo boats]], [[Torpedo bomber]]s and small submarines, was to set on a collision course abeam to the target and to release the torpedo at the last minute, before peeling away; all the time running a gauntlet of defensive fire. In larger ships and submarines, fire control calculators gave a wider engagement envelope. Originally, plotting tables (in large ships), combined with specialised [[slide rule]]s (known in U.S. service as the "banjo" and "Is/Was"),<ref>Beach, Edward L., Jr., Captain, USN (rtd). ''Run Silent, Run Deep''.</ref> reconciled the speed, distance, and course of a target with the firing ship's speed and course, together with the performance of its torpedoes, to provide a firing solution. By the Second World War, all sides had developed automatic electro-mechanical calculators, exemplified by the U.S. Navy's [[Torpedo Data Computer]].<ref>The British called theirs the "fruit machine".</ref> Submarine commanders were still expected to be able to calculate a firing solution by hand as a back up against mechanical failure, and because many submarines existing at the start of the war were not equipped with a TDC; most could keep the "picture" in their heads and do much of the math (which was simple trigonometry) without recourse to paper calculations, from extensive training.<ref>Beach describes it well in ''Run Silent, Run Deep''.</ref> Against high value targets and multiple targets, submarines would launch a spread of torpedoes, to increase the probability of success. Similarly, squadrons of torpedo boats and torpedo bombers would attack together creating a "fan" of torpedoes across the target's course. Faced with such an attack, the prudent thing for a target to do was to turn 90 degrees to its original course and steam away from the torpedoes and the firer, allowing the relatively short range torpedoes to use up their fuel. An alternative was to "comb the tracks", turning 90 degrees towards the torpedoes. The intention of such a tactic was still to minimise the size of target offered to the torpedoes, but at the same time be able to aggressively engage the firer. This was the tactic advocated by critics of Jellicoe's actions at [[Battle of jutland#Controversy|Jutland]], his caution at turning away from the torpedoes being seen as the reason the Germans escaped. The use of multiple torpedoes to engage single targets greatly reduces a submarine's combat endurance and its ability to stay on patrol.<ref>''The Attack Submarine'' suggests ''shorter'' patrols actually improve effectiveness.</ref> This can be improved by ensuring a target can be effectively engaged by a single torpedo, which gave rise to the guided torpedo. Guided torpedoes can use passive or active guidance, or a mix of the two. Passive [[acoustic torpedo]]es home in on emissions from a target. Active acoustic torpedoes home in on the reflection of a signal, or "ping", from the torpedo or its parent vehicle; this has the disadvantage of giving away the presence of the torpedo. In semi-active mode, a torpedo can be fired to the last known position or calculated position of a target, which is then acoustically illuminated ("pinged") once the torpedo is in attack range. Torpedoes can operate on a [[fire and forget]] principle or be controlled by its firing vessel. During the Second World War, the U.S. experimented with [[frequency hopping]] [[radio controlled]] torpedoes using matching pairs of [[punched card]] rolls based on those of [[player piano]]s. Modern torpedoes use an umbilical wire; the advantage of the umbilical is the vastly greater computer processing power of the submarine or ship can be used. Torpedoes such as the U.S. [[Mark 48 torpedo|Mark 48]] can operate in a variety of modes increasing tactical flexibility. ==Homing== The homing systems for torpedoes are generally acoustic, though there have been other target sensor types used. A ship's [[acoustic signature]] is not the only emission a torpedo can home in on. To engage U.S. supercarriers, the Soviet Union developed the [[53-65 torpedo|53-65]] [[wake]]-homing torpedo. ==Warhead/fuzing== The [[warhead]] is generally some form of [[aluminium|aluminised]] explosive, because the sustained explosive pulse produced by the powdered aluminium is particularly destructive against underwater targets. [[Torpex]] was popular until the 1950s, but has been superseded by [[polymer bonded explosive|PBX]] compositions. [[Nuclear warhead]]s for torpedoes have also been developed e.g. the [[Mark 45 torpedo]]. In lightweight antisubmarine torpedoes designed to penetrate submarine hulls, a [[shaped charge]] can be used. [[Detonation]] may be triggered by direct contact with the target, or by a [[proximity fuze]] incorporating sonar and/or magnetic sensors. ==Control surfaces and hydrodynamics== Control surfaces are essential for a torpedo to maintain its course and depth. A homing torpedo also needs to be able to out-manoeuvre a target. Good hydrodynamics are needed for it to attain high speed efficiently and also to give long range since the torpedo has limited stored energy. ==Torpedo classes and diameters== [[Image:Argonaute FS S636 p1040844.jpg|thumb|Torpedo tube aboard the French submarine ''Argonaute'']] Torpedoes are launched several ways: *From a [[torpedo tube]] mounted either in a trainable deck mount (common in [[destroyer]]s), or fixed above or below the waterline of a surface vessel (as in [[cruiser]]s, [[battleship]]s, and [[Auxiliary cruiser|armed merchant cruiser]]s) or [[submarine]]. *Early submarines, and some [[torpedo boat]]s (such as the U.S. WW2 [[PT boat]]s, which used tht [[Mark 13 torpedo|Mark 13]] aircraft torpedo) used deck-mounted "drop collars", which simply relied on gravity. *From shackles aboard low-flying [[torpedo bomber|aircraft]] or [[helicopter]]s. *As the final stage of a compound [[rocket]] or [[ramjet]] powered munition (sometimes called an '''assisted''' torpedo). Many navies have two weights of torpedoes: *A light torpedo used primarily as a close attack weapon, particularly by aircraft. *A heavy torpedo used primarily as a standoff weapon, particularly by submerged submarines. In the case of deck or tube launched torpedoes, the diameter of the torpedo is obviously a key factor in determining the suitability of a particular torpedo to a tube or launcher, similar to the [[caliber]] of the gun. The size is not quite as critical as for a gun, but diameter has become the most common way of classifying torpedoes. [[Image:Mark 48 Torpedo testing.jpg|thumb|Test firing of the [[Mark 48 torpedo]] by the Australian Navy aboard [[HMAS Torrens (DE-53)|HMAS ''Torrens'']].]] Length, weight, and other factors also contribute to compatibility. In the case of aircraft launched torpedoes, the key factors are weight, provision of suitable attachment points, and launch speed. Assisted torpedoes are the most recent development in torpedo design, and are normally engineered as an integrated package. Versions for aircraft and assisted launching have sometimes been based on deck or tube launched versions, and there has been at least one case of a submarine torpedo tube being designed to fire an aircraft torpedo. As in all [[munition]] design, there is a compromise between standardisation, which simplifies manufacture and [[logistics]], and specialisation, which may make the weapon significantly more effective. Small improvements in either logistics or effectiveness can translate into enormous operational advantages. Some common torpedo diameters (using the most common designation, metric or inch, and listed in increasing order of size): *'''12.75 inch''' (approximately 324 mm) is the most common size for light torpedoes. *'''406 mm''' (16 inch) was the size of the earliest specialised Soviet [[ASW]] torpedoes. {{convert|16|in|mm|0|sing=on}} torpedo tubes were fitted to Soviet [[Hotel class submarine|Hotel]], [[Echo class submarine|Echo]] and early [[Delta class submarine|Delta]] class submarines, often in addition to {{convert|21|in|mm|sing=on}} tubes. *'''450 mm''' (17.7 inch) was the standard size for light torpedoes of the [[Imperial Japanese Navy]]. It was also widely used by Italian Navy (Regia Marina) during World War II; it was the common size of the torpedo used by torpedo bomber. This size is sometimes referred to as {{convert|18|in|mm}}. *'''483 mm''' (19 inch) was the size for the first U.S. homing torpedo, the [[Mark 24 FIDO Torpedo|Mark 24]], also known as Fido. *'''533 mm''' (21 inch) is the most common size for heavy torpedoes, including: **Allied torpedoes of [[World War II]] **Imperial Japanese Navy submarines **Torpedoes of the ''[[Kriegsmarine]]'' **[[NATO]] torpedoes **Some [[Soviet]] and [[Russia]]n torpedoes, including the current ASW models *'''610 mm''' (24 inch) torpedoes, most famously the Type 93 ('Long Lance'), were used by Imperial Japanese Navy destroyers and cruisers, and as the basis for some ''[[Kaiten]]''. *'''650 mm''' (approximately 25.6 inches) is the largest torpedo diameter used by the Russian navy, such as the [[Type 65 torpedo|Type 65]]. Adaptors are used to fire 533 mm (21 inch) models from 650 mm tubes. Even larger sizes of [[torpedo tube]], including '''660 mm''' (26 inches), '''762 mm''' (30 inches), and '''916 mm''' (about 36 inches), have been installed on some nuclear submarines. These tubes are designed to be capable of firing large diameter munitions such as [[cruise missile]]s, as well as the standard 21 inch heavy torpedo. ==Torpedoes used by various navies== [[Image:Lynx mk46.jpg|thumb|A French ''[[Lynx (helicopter)|Lynx]]'' helicopter carrying a [[Mark 46 torpedo|mk46]] torpedo.]] [[Image:MU90.jpg|thumb|right|[[MU90 Impact]] triple launcher onboard F221 ''Hessen'' of the [[German Navy]].]] [[Image:Maille-Braize-14.jpg|thumb|A ''[[Malafon]]'' torpedo-carrying missile of the 1960s]] See also [[List of torpedoes]] ===German Navy=== Modern [[German Navy]]: *[[DM2A4|DM2A4 heavyweight torpedo]] *DM2A3 heavyweight torpedo *[[MU90 Impact|MU 90 lightweight impact torpedo]] *[[Mark 46 torpedo]] *Barracuda (supercaviating torpedo) The torpedoes used by the World War II [[Kriegsmarine]] included: * [[G7a torpedo|G7a]] (T1) * [[G7e torpedo|G7e]] (T2) * [[G7e_torpedo#G7e.2FT4_Falke|G7e/T4]] (Falke) * [[G7es torpedo|G7es]] (Zaunkönig) * [[T11 torpedo|T11]] ===Imperial Japanese Navy=== The torpedoes used by the [[Imperial Japanese Navy]] (World War II) included: * [[Type 91 torpedo]] * [[Type 92 torpedo]] * [[Type 93 torpedo]] * [[Type 95 torpedo]] * [[Type 97 torpedo]] * [[Kaiten]] ===Indian Navy=== * Advanced Experimental Torpedo (lightweight torpedo) * Varunastra (heavyweight torpedo) * Takshak (heavy weight torpedo) <ref>[http://www.drdo.org/labs/nr&d/nstl/achieve.shtml NSTL achievements]</ref> ===Royal Navy=== The torpedoes used by the [[Royal Navy]] include: * [[Spearfish torpedo]] * [[Stingray torpedo]] * [[Mark 24 Tigerfish|Tigerfish]] ===Russian Navy=== Torpedoes used by the [[Russian Navy]] include: * [[Type 53 torpedo]] * [[Type 65 torpedo]] * [[APR-3E torpedo]] * [[VA-111 Shkval torpedo]] ===U.S. Navy=== The four major torpedoes in the [[United States Navy]] inventory are: * the [[Mark 46 torpedo|Mark 46 lightweight]]; * the [[Mark 48 torpedo|Mark 48 heavyweight torpedo]]; * the [[Mark 50 torpedo|Mark 50 advanced lightweight]]; and * the [[Mark 54 LHT|Mark 54 Lightweight Hybrid Torpedo]]. ==Launchers== ===Ship=== [[Image:Velos D16 amidships.JPG|thumb|Amidships quintiple mounting for 21" torpedoes aboard the WW II era destroyer [[USS Charrette (DD-581)|USS Charrette]].]] Originally, Whitehead torpedoes were intended for launch underwater and the firm was upset when they found out the British were launching them above water, as they considered their torpedoes too delicate for this. However, the torpedoes survived. The launch tubes could be fitted in a ship's bow, which weakened it for ramming, or on the broadside; this introduced problems because of water flow twisting the torpedo, so guide rails and sleeves were used to prevent it. The torpedoes were originally ejected from the tubes by compressed air but later slow burning gunpowder was used. Torpedo boats originally used a frame which dropped the torpedo into the sea. Royal Navy [[Coastal Motor Boats]] of WW1 used a rear-facing trough and a [[cordite]] ram to push the torpedoes into the water tail-first. Developed in the run up to Second World War, multiple-tube mounts (up to quintuple in some ships) for 21" to 24" torpedoes in rotating turntable mounts appeared. Destroyers could be found with two or three of these mounts with between five and twelve tubes in total. The Japanese went one better, covering their tube mounts with splinter protection and adding reloading gear (both unlike any other navy in the world),<ref>Fitzsimons, Bernard, ed. ''Illustrated Encyclopedia of Weapons and Warfare'' (London: Phoebus, 1978), Volume 10, p.1040, "''Fubuki''"; Preston, Antony. ''Destroyers''.</ref> making them true turrets and increasing the broadside without adding tubes and [[top hamper]] (as the quadruple and quintuple mounts did). Considering their [[Type 93 torpedo|Type 93]]s possible war winners, IJN equipped their cruisers with torpedoes. The Germans also equipped their capital ships with torpedoes. Smaller vessels such as PT boats would carry their torpedoes in fixed deck mounted tubes using compressed air. These were either aligned to fire forward or at an angle to the centerline. Late in the war{{Fact|date=April 2008}} lightweight mounts for 12.75" homing torpedoes were developed for anti-submarine use consisting of triple launch tubes used on the decks of ships. These were the Mark 32 launcher in the USA and part of STWS (Shipborne Torpedo Weapon System) in the UK. Later a below-decks launcher has been used by the RN. This basic launch system continues to be used to this day with improved torpedoes and fire control systems. ===Submarines=== Submarine launched weapons now use compressed air, or the torpedoes swim out, or are pushed out by hydraulic ram. Both bow and stern tubes are usually fitted. The first French and Russian submarines carried their torpedoes externally in [[Drzewiecki]] [[drop collar]]s. These were cheaper than launch tubes but unreliable. Late in World War Two, the U.S. adopted a 16" (40cm) homing torpedo for use against escorts.<ref>Blair, Clay, Jr. ''Silent Victory'' (Lippencott, 1975); Lockwood, Charles A., Admiral. ''Hellcats of the Sea''.</ref> ===Air launch=== Torpedoes may be carried by fixed-wing aircraft, helicopters or missile. They are launched from the first two at prescribed speeds and altitudes, dropped from bomb-bays or underwing [[hardpoint]]s. ==Torpedo handling equipment== Although lightweight torpedoes are fairly easily handled, the transport and handling of heavyweight ones is difficult, especially in the small space of a submarine. After the Second World War, some Type XXI submarines were obtained from Germany by the United States and Britain. One of the main novel developments seen was a mechanical handling system for torpedoes. Such systems were widely adopted as a result of this discovery. ==See also== * [[List of torpedoes]] * [[Acoustic torpedo]] * [[Torpedo boat]] * [[Torpedo bomber]] * [[Submarine]] * [[Missile guidance]] * [[Human torpedo]] * [[Bangalore Torpedo]] * [[Autonomous Underwater Vehicle]] ==References== {{reflist}} ==Sources== *Blair, Clay. ''Silent Victory''. Philadelphia: Lippincott, 1975. *Milford, Frederick J. "U.S. Navy Torpedoes: Part One--Torpedoes through the Thirties". ''The Submarine Review'', April 1996. {quarterly publication of the Naval Submarine League, P.O. Box 1146, Annandale, VA, 22003) *_______. "U.S. Navy Torpedoes: Part Two--The Great Torpedo Scandal, 1941-43". ''The Submarine Review'', October 1996. *_______. "U.S. Navy Torpedoes: Part Three--WW II development of conventional torpedoes 1940-1946". ''The Submarine Review'', January 1997. *The Columbia Encyclopedia, Sixth Edition, online. *O'Kane, Richard H. (1987). "Seventh Patrol", ''Wahoo: The Patrols of America's Most Famous World War II Submarine''. Novato, California: Presidio Press. *Perry, Milton F. "Infernal Machines: The story of Confederate submarine and mine warfare." Louisiana State University Press, 1985. *Crowley, R.O. "Confederate Torpedo Service" in [[The Century Magazine|The Century]] / Volume 56, Issue 2, [[The Century Company]], New York, June 1898. ==External links== * Modern Torpedoes And Countermeasures [http://www.bharat-rakshak.com/MONITOR/ISSUE3-4/joseph.html] * US Navy torpedo data cut and pasted from a [http://www.chinfo.navy.mil/navpalib/factfile/weapons/wep-torp.html Navy Fact File] * A slightly more recent writeup on the Mk-48 is available at a [http://www.welshcoast.net/clwyd/ssbn624/torpedo.htm SSBN 624 web site by Clwyd] * Early History of the Torpedo [http://www.btinternet.com/~philipr/torps.htm Torpedo History] * US Naval Undersea Museum [https://www.keyportmuseum.cnrnw.navy.mil/torpedotech.htm Torpedo Display] * US Naval Undersea Museum [https://www.keyportmuseum.cnrnw.navy.mil/torpedoes.htm Torpedo Collection] * Super Cavitation Torpedo 'Barracuda' [http://www.diehl-bgt.de/index.php?id=550&L=1] [[Category:Torpedoes| ]] [[Category:unmanned vehicles]] <!-- interwiki --> [[ar:طوربيد]] [[cs:Torpédo]] [[da:Torpedo]] [[de:Torpedo]] [[et:Torpeedo]] [[el:Τορπίλη]] [[es:Torpedo]] [[eo:Torpedo]] [[fa:اژدر]] [[fr:Torpille]] [[ko:어뢰]] [[hr:Torpedo]] [[id:Torpedo]] [[it:Siluro]] [[he:טורפדו]] [[ka:ტორპედო (ჭურვი)]] [[hu:Torpedó]] [[ms:Torpedo]] [[nl:Torpedo (wapen)]] [[ja:魚雷]] [[no:Torpedo]] [[pl:Torpeda]] [[pt:Torpedo]] [[ru:Торпеда]] [[sl:Torpedo]] [[sr:Торпедо]] [[sh:Torpedo]] [[fi:Torpedo]] [[sv:Torped]] [[ta:நீர்மூழ்கிக் குண்டு]] [[vi:Ngư lôi]] [[uk:Торпеда]] [[ur:آبیگولہ]] [[zh:魚雷]] [[tr:torpil]]