Torpedo: Wikis

  
  
  
  

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German torpedo, 1900
Launching a torpedo in 1915 during World War I

The modern torpedo (historically called an automotive, automobile, locomotive, or fish torpedo; colloquially called "fish") 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 with, or in proximity to, a target. The term torpedo was originally used for a variety of devices, most of which would today be called mines. From about 1900 "torpedo" has been used only for an underwater self-propelled missile.

While the battleship had evolved primarily around engagements between armoured ships with large guns, the torpedo allowed torpedo boats and other lighter surface ships, submersibles, and aircraft to destroy large armored ships without the use of large-caliber guns, though sometimes at the risk of being hit by longer-range shellfire.

Today's torpedoes can be divided into lightweight and heavyweight classes; and into straight-running, autonomous homers and wire-guided. They can be launched from a variety of platforms.

Contents

Etymology

The word torpedo comes from a genus of electric rays in the order Torpediniformes, which in turn comes from the Latin "torpere" (to be stiff or numb). 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 to demonstrate that it could sink warships.

History

Before 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 traps, land mines and naval mines.

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 Syrian 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.[1]

Early naval "torpedoes"

Confederates laying torpedoes in Charleston Harbor

Although the term "torpedo" was not coined until 1800, the early 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 attach its charge to the hull of HMS Eagle.

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 contact mine, floating on or below the water surface using an air-filled 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 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 too far from the batteries. Former United States Navy Commander Matthew Maury, who served as a commander in the 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, 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!"

CSS David with spar torpedo

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 30 feet (9.1 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 (and were successful in sinking the USS Housatonic), as well as by David-class torpedo boats, among others. However, these torpedoes were apt to cause as much harm to their users as to their targets.

Bombs and booby traps

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 boobytraps. Confederate General Gabriel J. Rains deployed "sub-terra shells" or "land torpedoes", artillery shells with pressure 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.[2] 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. The explosion caused more than 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

Nordenfelt-class Ottoman submarine Abdülhamid (1886) was the first submarine in history to fire a torpedo while submerged.

From the 1870s onwards, the word torpedo was increasingly used only to describe self-propelled projectiles that traveled under or on water. By the turn of the century, the term no longer included mines and booby-traps as the navies of the world added submarines, torpedo boats and torpedo boat destroyers to their fleets.

One of the torpedoes used by Abdülhamid and Abdulmecit.

The first working prototype of the modern self-propelled torpedo was created by a commission placed by Giovanni Luppis (Ivan Lupis), an Austrian naval officer from Rijeka/Fiume, a port city of the Austrian Empire, and Robert Whitehead, an 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, attached ropes, and 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 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 hydrostatic valve and pendulum that 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, he improved the devices to travel up to approximately 1,000 yd (910 m) at a speed of up to 6 kn (11 km/h), and by 1881 the factory was exporting torpedoes to ten other countries. The torpedo was powered by compressed air and had an explosive charge of gun-cotton[3]. Whitehead went on to develop more efficient devices, demonstrating torpedoes capable of 18 kn (33 km/h) in 1876, 24 kn (44 km/h) in 1886, and, finally, 30 kn (56 km/h) in 1890.

Royal Navy representatives visited Fiume for a demonstration in late 1869, and in 1870 a batch of torpedoes was ordered. In 1871, the British Admiralty paid Whitehead £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 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, with diameters from 14 in (36 cm) upward. The largest Whitehead torpedo was 18 in (46 cm) in diameter and 19 ft (5.8 m) long, made of polished steel or phosphor-bronze, with a 200-pound (91 kg) gun-cotton warhead. It was propelled by a three-cylinder Brotherhood engine, using compressed air at around 1,300 psi (9.0 MPa) and driving two propellers, and 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 A. Howell, whose own design, driven by flywheel, was simpler and cheaper. It was produced from 1885 to 1895, and it ran straight, leaving no wake. A Torpedo Test Station had been set up on Rhode Island in 1870, and an automobile torpedo produced in 1871 was unsuccessful. The Lay torpedoes were also largely unsuccessful as were various privately invented types. The Howell torpedo was the only USN model until Whitehead torpedoes produced by Bliss and Williams (later E W Bliss and Co) entered service in 1894. Five varieties were produced, all 18 in (46 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 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.

Torpedo boat attack on the Chilean battery ship Cochrane during the Chilean Civil War

On 16 January 1878, the Turkish steamer Intibah became the first vessel to be sunk by self-propelled torpedoes, launched from torpedo boats operating from the tender Velikiy Knyaz Konstantin under the command of Stepan Osipovich Makarov during the Russo-Turkish War of 1877-78. In another early use of the torpedo, Chilean frigate Blanco Encalada (1875) 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 Thornycroft in 1877, had gained recognition for its effectiveness, and the first torpedo boat destroyers (later simply destroyers) were built to counter it. Torpedoes were also used to equip gunboats of around 1,000 tons, these becoming torpedo gunboats.

Originally, torpedoes were designed to be straight running, though this was not always the case in practice. Around 1897, Nikola Tesla patented a remote controlled boat and later demonstrated the feasibility of radio-guided torpedoes to the United States military.

In 1915, Admiral Bradley A. Fiske imagined that an aerial torpedo attack would be carried out close to the water and at night.

The idea of dropping lightweight torpedoes from aircraft was conceived in the early 1910s by Bradley A. Fiske, an officer in the United States Navy.[4] Awarded a patent in 1912,[5] [6] Fiske worked out the mechanics of carrying and releasing the aerial torpedo from a bomber, and defined tactics that included a night-time approach so that the target ship would be less able to defend itself. Fiske determined that the notional torpedo bomber should descend rapidly in a sharp spiral to evade enemy guns, then when about 10 to 20 feet (3 to 6 m) above the water the aircraft would straighten its flight long enough to line up with the torpedo's intended path. The aircraft would release the torpedo at a distance of 1,500 to 2,000 yards (1,400 to 1,800 m) from the target.[4] Fiske reported in 1915 that, using this method, enemy fleets could be attacked within their own harbors if there were enough room for the torpedo track.[7]

World War I

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).[8] Britain and its allies also used torpedoes throughout the war. U-boats themselves were often targeted, twenty being sunk by torpedo.

Initially the Japanese Navy purchased Whitehead or Schwartzkopf torpedoes but by 1917 they were conducting experiments with pure oxygen instead of compressed air. 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.

World War II

The Naval Torpedo Station in Alexandria, Virginia was one of three United States Navy factories to manufacture torpedoes during World War II.

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, nicknamed Long Lance postwar by historian Samuel E. Morison) at the start of World War II. The lack of reliability caused major problems for the American Submarine Force in the early 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 rules of war. (In the event, merchantmen were armed and acted as de facto naval auxiliaries, rendering the distinction irrelevant.) There was concern torpedoes would be ineffective against warships' heavy armor; an answer to this was to detonate torpedoes underneath a ship, badly damaging its keel and the other structural members in the hull, commonly called "breaking its back". This was demonstrated by magnetic influence mines in World War I. The torpedo would be set to run at a depth just beneath the ship, relying on a magnetic exploder to activate at the appropriate 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 pistols 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, and fully-functioning torpedoes only became available to the USN 21 months into the Pacific War.[9]

British submarines used torpedoes to interdict the Axis supply shipping to North Africa, while Fleet Air Arm Swordfish sank three Italian battleships at Taranto by torpedo and (after a mistaken, but abortive, attack on Sheffield) scored one crucial hit in the hunt for the German battleship Bismarck. Large tonnages of merchant shipping were sunk by submarines with torpedoes in both the Battle of the Atlantic and the Pacific War.

Torpedo boats such as the American PT boats enabled relatively small but fast boats to carry enough firepower, in theory, to destroy a larger ship, though this rarely occurred in practice. Destroyers of all navies were also usually armed with torpedoes to attack larger ships. In the Battle off Samar, destroyer-mounted torpedoes of the American task force "Taffy 3" showed effectiveness at defeating armor. Damage and confusion caused by torpedo attacks were instrumental in beating back a superior Japanese force of battleships and cruisers.[10]

Post-World War II

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.

In postwar times, only the navies of Pakistan and the United Kingdom have made torpedo hits against hostile navy ships. The sinkings of INS Khukri and ARA General Belgrano caused a combined death toll of approximately 500.

During the Korean War the United States Navy successfully attacked a dam with air-launched torpedoes.[11]

Energy sources

The USS Mustin (DDG-89) launches a dummy torpedo during exercises

Compressed air

This first successful self-propelled Whitehead torpedo of 1866 used compressed air as its energy source. The air was stored at pressures of up to 2.55 MPa (370 psi) and fed to a piston engine which turned a single propeller at about 100 rpm. It was able to travel about 180 metres (200 yd) at an average speed of 6.5 knots (12.0 km/h). The speed and range of later models was improved by increasing the pressure of the stored air. In 1906 Whitehead built torpedoes which could cover nearly 1,000 metres (1,100 yd) at an average speed of 35 knots (65 km/h).

At higher pressures the cooling experienced by the air as it expanded in the engine caused icing problems (see adiabatic cooling). This drawback 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 circa 1904 by Whitehead's company.

Wet-heater

A further improvement 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 21% oxygen, engineers in Japan developed the Type 93 "Long Lance" for destroyers and cruisers in the 1930s. It used pure compressed oxygen instead of compressed air and had unmatched performance in World War II. However, oxygen systems posed a serious danger to any ship that came under attack while still carrying such torpedoes; Japan lost several cruisers partly due to catastrophic secondary explosions of Type 93s. During the war, Germany experimented with hydrogen peroxide for the same purpose.

U.S. World War II torpedo belonging to PT-658 in Portland, Oregon.

Wire driven

The Brennan torpedo had two wires wound around drums inside it. Shore-based steam winches pulled the wires, which spun the drums and drove the propellers. An operator controlled the relative speeds of the winches, providing guidance. Such systems were used for coastal defence of the British homeland and colonies from 1887 to 1903 and were purchased by, and under the control of, the Army as opposed to the Navy. Speed was about 25 knots (46 km/h) 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 400 yards (370 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 Whitehead models.

Electric batteries

Electric batteries of a French Z13 torpedo.

Electric propulsion systems 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 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 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 cells.

The United States had an electric design, the Mark 18, largely copied from the German torpedo (although with improved batteries), as well as FIDO, an air-dropped acoustic homing torpedo for anti-submarine use.

Modern electric torpedoes such as the Mark 24 Tigerfish or DM2 series commonly use 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 but they were not successful. Rocket propulsion has recently been revived in Russian and German torpedoes (see below): it is especially suitable for supercavitating devices.

Modern drive systems

Modern torpedoes utilize a variety of drive mechanisms, including gas turbines (the British Spearfish), monopropellants, and sulphur hexafluoride gas sprayed over a block of solid lithium.

Propulsion

The first of Whitehead's torpedoes had a single propeller and needed a large vane to stop it turning in a circle. Not long afterward the idea of contra-rotating propellers was introduced (at Woolwich), to avoid the need for 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.

Some torpedoes, such as the Russian VA-111 Shkval, the Iranian Hoot and the proposed German Unterwasserlaufkörper / Barracuda,[12] use supercavitation to increase their speed to over 200 knots (370 km/h); the maximum speed of torpedoes which do not use supercavitation, such as the American Mark 48 and British Spearfish, is well under 100 kn (120 mph; 190 km/h), although figures are not always supplied.

Guidance

A torpedo dropped from a Sopwith Cuckoo during World War I.
Illustration of General Torpedo Fire Control Problem

Torpedoes may aimed at the target and fired unguided, similarly to an artillery shell, or they may be guided onto the target. They may be guided automatically towards the direction in which the target is detected by some procedure, e.g. sound it produces (homing), or by the operator, typically via commands sent over a signal-carrying cable (wire guidance).

Unguided

The Victorian era Brennan could be steered onto its target by varying the relative speeds of its propulsion cables. However, the Brennan required a substantial infrastructure and was not suitable for shipboard use. Therefore, for the first part of its history, the torpedo was guided only in the sense that its course could be regulated so as to achieve an intended impact depth (because of the sine wave running path of the Whitehead,[13] 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 small torpedo boats, Torpedo bombers and small submarines was to steer a predictable collision course abeam to the target and release the torpedo at the last minute, then peeling away, all the time subject to 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 rules (known in U.S. service as the "banjo" and "Is/Was"),[14] 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.[15] Submarine commanders were still expected to be able to calculate a firing solution by hand as a backup 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 calculations (simple trigonometry) mentally, from extensive training.[16]

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 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 depletes torpedo supplies and greatly reduces a submarine's combat endurance.[17] Endurance can be improved by ensuring a target can be effectively engaged by a single torpedo, which gave rise to the guided torpedo.

Wire guidance

Though Lupis' original design had been rope guided, torpedoes were not wire-guided until the 1960s. 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 pianos.

Modern torpedoes use an umbilical wire, which nowadays allows the computer processing power of the submarine or ship to be used. Torpedoes such as the U.S. Mark 48 can operate in a variety of modes, increasing tactical flexibility.

Homing

Homing "fire and forget" torpedoes can use passive or active guidance, or a combination of both. Passive acoustic torpedoes 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.

Later in the Second World War torpedoes were given acoustic (homing) guidance systems, originally by the Germans in the G7es torpedo. Pattern-following and wake homing torpedoes were also developed. Acoustic homing formed the basis for torpedo guidance after the Second World War.

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 wake-homing torpedo.

Warhead and fuzing

The warhead is generally some form of 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 PBX compositions. Nuclear warheads 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 can 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.

Launch platforms and launchers

A Mark 32 Mod 15 Surface Vessel Torpedo Tube (SVTT) fires a Mark 46 Mod 5 lightweight torpedo.

Torpedoes may be launched from submarines, surface ships, helicopters and fixed-wing aircraft, unmanned naval mines and naval fortresses. 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) and the CAPTOR mine (CAPsulated TORpedo) is a submerged sensor platform which releases a torpedo when a hostile contact is detected.

Ship

Amidships quintuple mounting for 21" torpedoes aboard the WW II era destroyer 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 that dropped the torpedo into the sea. Royal Navy Coastal Motor Boats of World War I used a rear-facing trough and a cordite ram to push the torpedoes into the water tail-first; they then had to move rapidly out of the way to avoid being hit by their own torpedo.

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),[18] making them true turrets and increasing the broadside without adding tubes and top hamper (as the quadruple and quintuple mounts did). Considering their Type 93s very effective weapons, the IJN equipped their cruisers with torpedoes. The Germans also equipped their capital ships with torpedoes.

Smaller vessels such as PT boats carried their torpedoes in fixed deck mounted tubes using compressed air. These were either aligned to fire forward or at an offset angle from the centerline.

Later, 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 1960 Mk 32 torpedo launcher in the USA and part of STWS (Shipborne Torpedo Weapon System) in the UK. Later a below-decks launcher was used by the RN. This basic launch system continues to be used today 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 collars. These were cheaper than launch tubes but unreliable.

Late in World War II, the U.S. adopted a 16" (40 cm) homing torpedo for use against escorts.[19]

Air launch

Aerial torpedoes may be carried by fixed-wing aircraft, helicopters or missiles. They are launched from the first two at prescribed speeds and altitudes, dropped from bomb-bays or underwing hardpoints.

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.

Torpedo classes and diameters

Torpedo tube aboard the French submarine Argonaute

Torpedoes are launched several ways:

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.

Test firing of the Mark 48 torpedo by the Australian Navy to scuttle 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. 16-inch (406 mm) torpedo tubes were fitted to Soviet Hotel, Echo and early Delta class submarines, often in addition to 21-inch (530 mm) 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 18 inches (460 mm).
  • 483 mm (19 inch) was the size for the first U.S. homing torpedo, the Mark 24, also known as Fido.
  • 533 mm (21 inch) is the most common size for heavy torpedoes, including:
  • 550 mm (approximately 21.7 inches) was the standard size for French Navy torpedoes until France joined NATO and switched to 533 mm
  • 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. 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 missiles, as well as the standard 21 inch heavy torpedo.

Torpedoes used by various navies

A French Lynx helicopter carrying a mk46 torpedo.
MU90 Impact triple launcher onboard F221 Hessen, a Sachsen class frigate of the German Navy.
A Malafon torpedo-carrying missile of the 1960s

German Navy

Modern German Navy:

The torpedoes used by the World War II Kriegsmarine included:

Imperial Japanese Navy

The torpedoes used by the Imperial Japanese Navy (World War II) included:

Indian Navy

PLA Navy (China)

Royal Navy

The torpedoes used by the Royal Navy include:

Russian Navy

Torpedoes used by the Russian Navy include:

U.S. Navy

The four major torpedoes in the United States Navy inventory are:

See also

Notes

  1. ^ Prof. Dr. Mohamed Mansour (2002-03-22). "Muslim Rocket Technology". MuslimHeritage.com. http://muslimheritage.com/topics/default.cfm?ArticleID=284. Retrieved 2007-07-18. 
  2. ^ The City Point Explosion (MilitaryHistoryOnline.com)
  3. ^ The Whitehead Torpedo, notes on handling etc., U. S. N., 1890
  4. ^ a b Hopkins, Albert Allis. The Scientific American War Book: The Mechanism and Technique of War, Chapter XLV: Aerial Torpedoes and Torpedo Mines. Munn & Company, Incorporated, 1915
  5. ^ US1,032,394 (PDF version) (1912-07-16) Bradley A. Fiske, Method of and apparatus for delivering submarine torpedoes from airships. 
  6. ^ Hart, Albert Bushnell. Harper's pictorial library of the world war, Volume 4. Harper, 1920, p. 335.
  7. ^ The New York Times, July 23, 1915. "Torpedo Boat That Flies. Admiral Fiske Invents a Craft to Attack Fleets in Harbors" Retrieved on September 29, 2009.
  8. ^ The war's top ace used them exclusively, and stuck religiously to the "cruiser rules"
  9. ^ Blair, p.20
  10. ^ Battle Off Samar
  11. ^ Faltum, Andrew (1996). The Essex Aircraft Carriers. Baltimore, Maryland: The Nautical & Aviation Publishing Company of America. pp. 125–126. ISBN 1-877853-26-7. 
  12. ^ Diehl BGT: Unterwasserlaufkörper
  13. ^ Fitzsimons, Bernard, ed. "Bliss-Leavitt", in The Illustrated Encyclopedia of 20th Century Weapons and Warfare (London: Phoebus, 1978), Volume 4, p.386.
  14. ^ Beach, Edward L., Jr., Captain, USN (rtd). Run Silent, Run Deep.
  15. ^ The British called theirs the "fruit machine".
  16. ^ Beach describes it well in Run Silent, Run Deep.
  17. ^ The Attack Submarine suggests shorter patrols actually improve effectiveness.
  18. ^ Fitzsimons, Bernard, ed. Illustrated Encyclopedia of Weapons and Warfare (London: Phoebus, 1978), Volume 10, p.1040, "Fubuki"; Preston, Antony. Destroyers.
  19. ^ Blair, Clay, Jr. Silent Victory (Lippencott, 1975); Lockwood, Charles A., Admiral. Hellcats of the Sea.
  20. ^ NSTL achievements

References

  • Blair, Clay. Silent Victory. Philadelphia: Lippincott, 1975.
  • The Columbia Encyclopedia, Sixth Edition, online.
  • Crowley, R.O. "Confederate Torpedo Service". The Century, Volume 56, Issue 2, The Century Company, New York, June 1898.
  • 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)
  • Milford, Frederick J. "U.S. Navy Torpedoes: Part Two—The Great Torpedo Scandal, 1941-43". The Submarine Review, October 1996.
  • Milford, Frederick J. "U.S. Navy Torpedoes: Part Three—WW II development of conventional torpedoes 1940–1946". The Submarine Review, January 1997.
  • 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. Baton Rouge: Louisiana State University Press, 1985. ISBN 0807112852.

External links


1911 encyclopedia

Up to date as of January 14, 2010

From LoveToKnow 1911

TORPEDO. In 1805 Robert Fulton demonstrated a new method of destroying ships by exploding a large charge of gunpowder against the hull under water. No doubt then remained as to the effectiveness of this form of attack when successfully applied; it was the difficulty of getting the torpedo, as it was called, to the required position which for many years retarded its progress as a practical weapon of naval warfare. Attempts were first made to bring the explosive in contact with the vessel by allowing it to drift down to her by the action of tide or current, and afterwards to fix it against her from some form of diving boat, but successive failures led to its restriction for a considerable period to the submarine mine (q.v.) in which the explosive is stationary and takes effect only when the ship itself moves over or strikes the charge. Used in this way, it is an excellent deterrent to hostile warships forcing a harbour.

Table of contents

Spar or Outrigger Torpedo

The limitations attached to the employment of submarine mines, except for coast defence, revived the idea of taking the torpedo to the ship instead of waiting for the latter to gain some exact point which she might very possibly avoid. This first took practical shape in the spar or outrigger torpedo. This consisted of a charge of explosive at the end of a long pole projecting from the bow of a boat, the pole being run out and immersed on arriving near the object. Directly the charge came in contact with the hull of the ship it was exploded by an electric battery in the boat. If the boat was not discovered and disabled while approaching, the chances were favourable to success and escape afterwards. Against a vigilant enemy it was doubtless a forlorn hope, but to brave men the venture offered considerable attractions.

Frequent use of this spar or outrigger torpedo was made during the American Civil War. A notable instance was the destruction of the Confederate ironclad "Albemarle" at the end of October 1864. On this mission Lieut. Cushing took a steam launch equipped with an outrigger torpedo up the Roanoke River, in which lay the "Albemarle." On arriving near the ship Cushing found her surrounded by logs, but pushing his boat over them, he immersed the spar and exploded his charge in contact with the "Albemarle" under a heavy fire. Ship and launch sank together, but the gallant officer jumped overboard, swam away and escaped. Submerged boats were also used for similar service, but usually went to the bottom with their crews. During the war between France and China in 1884 the "Yang Woo" was attacked and destroyed by an outrigger torpedo.

Locomotive Torpedoes

Though the spar torpedo had scored some successes, it was mainly because the means of defence against it at that time were inefficient. The ship trusted solely to her heavy gun and rifle fire to repel the attack. The noise, smoke, and difficulty of hitting a small object at night with a piece that could probably be discharged but once before the boat arrived, while rifle bullets would not stop its advance, favoured the attack. When a number of small guns and electric lights were added to a ship's equipment, success with an outrigger torpedo became nearly, if not entirely, impossible. Attention was then turned in the direction of giving motion to the torpedo and steering it to the required point by electric wires worked from the shore or from another vessel; or, dispensing with any such connection, of devising a torpedo which would travel under water in a given direction by means of self-contained motive power and machinery. Of the former type are the Lay, SimsEdison and Brennan torpedoes. The first two - electrically steered by a wire which trails behind the torpedo - have insufficient speed to be of practical value, and are no longer used. The Brennan torpedo, carrying a charge of explosive, travels under water and is propelled by unwinding two drums or reels of fine steel wire within the torpedo. The rotation of these reels is communicated to the propellers, causing the torpedo to advance. The ends of the wires are connected to an engine on shore to give rapid unwinding and increased speed to the torpedo. It is steered by varying the speed of unwinding the two wires. This torpedo was adopted by the British war office for harbour defence and the protection of narrow channels.

Uncontrolled Torpedoes

The objection of naval officers to have any form of torpedo connected by wire to their ship during an action, impeding her free movement, liable to get entangled in her propellers and perhaps exploding where not desired - disadvantages which led them to discard the Harvey towing torpedo many years ago - has hitherto prevented any navy from adopting a controlled torpedo for its sea-going fleet. The last quarter of the 19th century saw, however, great advances in the equipment of ships with locomotive torpedoes of the uncontrolled type. The Howell may be briefly described, as it has a special feature of some interest. Motive power is provided by causing a heavy steel fly-wheel inside the torpedo to revolve with great velocity. This is effected by a small special engine outside operating on the axle. When sufficiently spun up, the axle of the flywheel is connected with the propeller shafts and screws which drive the torpedo, so that on entering the water it is driven ahead and continues its course until the power stored up in the flywheel is exhausted. Now when a torpedo is discharged into the sea from a ship in motion, it has a tendency to deflect owing to the action of the passing water. The angle of deflexion will vary according to the speed of the ship, and is also affected by other causes, such as the position in the ship from which the torpedo is discharged, and its own angle with the line of keel. Hence arise inaccuracies of shooting; but these do not occur with this torpedo, for the motion of the flywheel, acting as a gyroscope - the principle of which applied to the Whitehead torpedo is described later - keeps this torpedo on a straight course. This advantage, combined with simplicity in construction, induced the American naval authorities at one time to contemplate equipping their fleet with this torpedo, for they had not, up to within a few years ago, adopted any locomotive torpedo. A great improvement in the torpedo devised by Mr Whitehead led them, however, definitely to prefer the latter and to discontinue the further development of the Howell system.

The Whitehead torpedo is a steel fish-shaped body which travels under water at a high rate of speed, being propelled by two screws driven by compressed air. It carries a large charge of explosive which is ignited on the torpedo striking any hard substance, such as the hull of a ship. The body is divided into three parts. The foremost portion or head contains the explosive - usually wet gun-cotton - with dry primer and mechanical igniting arrangement; the centre portion is the air chamber or reservoir, while the remaining part or tail carries the engines, rudders, and propellers besides the apparatus for controlling depth and direction. This portion also gives buoyancy to the torpedo.

When the torpedo is projected from a ship or boat into the water a lever is thrown back, admitting air into the engines causing the propellers to revolve and drive the torpedo ahead. It is desirable that a certain depth under water should be maintained. An explosion on the surface would be deprived of the greater part of its effect, for most of the gas generated would escape into the air. Immersed, the water above confines the liberated gas and compels it to exert all its energy against the bottom of the ship. It is also necessary to correct the tendency to rise that is due to the torpedo getting lighter as the air is used up, for compressed air has an appreciable weight. This is effected by an ingenious apparatus long maintained secret. The general principle is to utilize the pressures due to different depths of water to actuate horizontal rudders, so that the torpedo is automatically directed upwards or downwards as its tendency is to sink or rise.

The efficiency of such a torpedo compared with all previous types was clearly manifest when it was brought before the maritime states by the inventor, Whitehead, and it was almost universally adopted. The principal defect was want of speed - which at first 7'011 - __----- ------- FIG. 1. - Diagrams of 14and 18-in. Torpedoes.

did not exceed 10 knots an hour - but by the application of Brotherhood's 3-cylinder engine the speed was increased to 18 knots - a great advance. From that time continuous improvements have resulted in speeds of 30 knots and upwards for a short range being obtained. For some years a torpedo 14 ft. long and 14 in. in diameter was considered large enough, though it had a very limited effective range. For a longer range a larger weapon must be employed capable of carrying a greater supply of air. To obtain this, torpedoes of 18 in. diameter, involving increased length and weight, have for some time been constructed, and have taken the place of the smaller torpedo in the equipment of warships. This advance in dimensions has not only given a faster and steadier torpedo, but enabled such a heavy charge of gun-cotton to be carried that its explosion against any portion of a ship would inevitably either sink or disable her. The dimensions, shape, &c., of the 14and 18-in. torpedoes are shown in fig. 1. A limited range was still imposed by the uncertainty of its course under water. The speed of the ship from which it was discharged, the angle with her keel at which it entered the water, and the varying velocity of impulse, tended to error of flight, such error being magnified the farther the path of the torpedo was prolonged. Hence 800 yards. was formerly considered the limit of distance within which the torpedo should be lol discharged at sea against an object from a ship in motion.

In these circumstances, though improvements in the manufacture of steel and engines allowed of torpedoes of far longer range being, 18-[[Inch Torpedo - 14-Inch Torpedo]].

made (the fastest torpedo up to 1898 having a speed of 29 knots for 800 yds.), it was of no advantage to make them, as they could not be depended upon to run in a straight line from a stationary point for more than 800 yds., while from a ship in motion good practice could only be ensured at a reduced range. It was obvious, therefore, that to increase the effective range of the torpedo, these errors of direction must be overcome by some automatic steering arrangement. Several inventors turned their attention to the subject, nearly all of whom proposed to utilize the principle of the gyroscope for the purpose. The first which gave any satisfactory results was an apparatus devised by Ludwig Obry - an engineer in Austria - and tried by the Italian government about 1896. These trials demonstrated the feasibility of accurately and automatically steering a torpedo in a direct line by this means. Messrs Whitehead & Co., of Fiume, then acquired the invention, and after exhaustive experiments produced the apparatus which is now fitted to every torpedo made. It is based on the principle that a body revolving on a free axis tends to preserve its plane of rotation. A gyroscope with plane of rotation parallel to the vertical axis of the torpedo will have an angular motion if the torpedo is diverted from its original course. This angular motion is employed to actuate the steering mechanism by operating an air motor connected with the rudders, and keeping the torpedo in the line of discharge. The apparatus consists of a flywheel caused to rotate by a spring, the barrel on which the latter is wound having a segmental wheel which gears into a toothed pinion spindle of the flywheel. Owing to the diameter of the segment being much greater than the pinion, a rapid rotatory motion is imparted. The spring is wound up by a key from outside the torpedo, and kept in tension until the projectile is discharged, when the spring is released by the air lever being thrown back, which admits air to the engine; the gyroscope is then freed and set in motion with its plane in the plane of the vertical axis of the torpedo as it was in the launching tube.

Assuming now that the course of the torpedo is diverted by any cause, its axis will move or perform a certain angular motion with regard to the plane of the flywheel, which will have the same result as if we consider the conditions reversed, i.e. as if the plane of rotation of the flywheel were altered and that of the axis of the torpedo remained the same. The axis of the flywheel performs a relative angular motion which it imparts to a crank actuating a servo-motor worked by compressed air, and connected with the rudders of the torpedo, moving them in the opposite direction to that in which the torpedo was diverted from its original course. Thus all inaccuracies of flight due to errors of adjustment, miscalculation of deflexion, or even damage to some part, are eliminated. As long as the gyroscope is in good order the torpedo is bound to run in the line it was pointing when the flywheel was started. It is placed in the after-body of the torpedo, as indicated in fig.

limited by the strength of the engines and other parts. Improvements in steel manufacture have permitted the use of much higher pressures of air and the construction of air-chambers able to withstand the pressure of 2000 lb to the sq. in. with the same weight of air-chamber. This has enabled increased range without reduction in speed to be attained, or conversely, increased speed at shorter ranges. By improvement in the engines which are now of the Brotherhood 4-cylinder central crank type further gains have been effected.

Having reached the limit of pressure and endurance of airchambers with present materials without undue increase of weight, the designer had to seek additional energy in another direction. Now the energy obtainable from a given weight of compressed air is dependent upon the volume of air available at the working pressure of the engines. At a constant pressure this volume of air is proportionate to its absolute temperature. If then the air be stored cold and highly heated before delivery to the engine the available energy from a given weight will be greatly increased. By this means we obtain the equivalent of a larger and heavier air-chamber without the increased weight such would involve.

As originally used a quantity of hydrocarbon fuel was placed in the air-vessel. Upon discharging the torpedo this fuel was automatically ignited and the contents of the air-chamber were heated. Unless, however, the combustion could be regulated there were serious risks of abnormal pressures, of overheating and weakening the air-vessel. Devices have been applied to overcome this liability, and other methods devised to obtain the same result.

By the use of heating and thereby increasing the volume of air in proportion to the rise of temperature the extra volume will allow of an increased speed for a given range or a greater range without increase of speed. The limit to the development of this system seems to be the temperature the materials will stand, but even at this early stage it has added several knots to the speed of this wonderful weapon.

Torpedo Carriages and Discharge

As no gun which is inefficiently mounted can give good results, so the best torpedo is valueless without a good carriage or system of discharge. In the early days of the Whitehead, discredit came upon it because the importance of this was not sufficiently realized; and an erratic course under water was in nine cases out of ten due to a crude method of discharge. A delicate piece of mechanism was dropped into the water from a height of several feet, and naturally suffered internal derangement. Gun-ports were then used for the purpose, but now a special orifice is made, to which the torpedo carriage is fitted with a balland-socket joint - forming a water-tight aperture - so that this carriage or tube may be only 2 or 3 ft. above the water-line. The ball-and-socket joint enables it also to have a considerable angle of training. Originally the torpedo was pushed out by a rod acted upon by compressed air, in which case the carriage was a Engine Room After Body Fig. 2. - Arrangement of Gyroscope in Torpedo.

The efficiency of the Whitehead torpedo has thus been enormously increased, and more accurate practice can now be made at 2000 yds. than was formerly possible at 800 yds. This adds considerably to the chances of torpedo-boats attacking ships, even in day-time, at sea or at anchor, and will render further protection necessary against this weapon. Against a ship in motion there is still, however, the calculation as to her speed and the distance she will travel before the to y pedo reaches her. Should this be miscalculated, an increased range for torpedoes will magnify the error. For instance, a 30-knot torpedo will travel loon yds. in a minute. If aimed at a ship on the beam assumed to be steaming 15 knots an hour, to reach her when loon yds. distant the torpedo must be discharged at a point 500 yds. ahead of her. But if the ship is actually steaming 12 knots, she will have travelled only 400 yds. in the minute, and the torpedo will be 100 yds. in advance of her. If discharged at a range of 500 yds., such a miscalculation causes an error of only 50 yds. or 150 ft. But if the object is 300 tt. long, and her centre was taken as the target, her bow would be just at the spot the torpedo would reach in thirty seconds. It would seem, therefore, that increased velocity of torpedo is necessary before the full advantages of the gyroscope can be realized. Now the range of the torpedo is entirely dependent upon the store of energy which can be carried; upon, therefore, the capacity of the air reservoir, the maximum pressure it can stand, and on the efficiency of the propelling engines. The speed over a given range is also dependent upon these factors; the maximum speed being simple frame. The rod, pressing against the tail with some force, was apt to damage or disarrange the rudders, so the air-gun took the place of rod impulse. Here the torpedo fits closely in a tube or cylinder with an opening at the rear made air-tight when closed. At the desired moment compressed air is admitted to the rear part of the cylinder and blows the torpedo out. Gunpowder then superseded air for this operation; and now this has given place to a small charge of cordite, which does not leave any deposit on the inside of the cylinder. There is a double risk in the use of locomotive torpedoes from above water. (1) The charge may be exploded by hostile fire. Though mainly consisting of damp gun-cotton, which is not readily ignited, the dry primer and detonator may be struck, which would lead to a disastrous explosion. (2) The airchamber is also a source of danger. As it contains air compressed to a high degree of tension, experiments have shown that if struck by a small shell it may burst with great violence; and as it offers a considerable mark, this is not an improbable event in an action. An instance of the danger of above-water torpedo tubes occurred in the Spanish-American War at the battle of Santiago. A shell entered the "Almirante Oquendo" and struck a 14-in. torpedo in the tube. The charge detonated, causing a fearful explosion and practically wrecking that part of the vessel. The development of moderate-sized quick-firing guns has increased this risk. Hence we find the use of above-water torpedo tubes now mainly confined to torpedo and other craft too small for submerged discharge.

Submerged Discharge

The risk attached to having loaded torpedoes above the water-line - independently of the fact that to get the best result they should start in the element to which they belong - has given great impetus to the system of submerged and tube into the ship again, so that practically the whole operation is one motion.

Fig. 3 will further explain this apparatus. A is the outer tube; B the inner tube; C the shield; D torpedo; E explosion chamber for cordite charge placed at K; F pipe for gas to pass into outer tu'3e; G and Y doors of inner and outer tube; J the valve which opens automatically when inner tube arrives at position shown in fig. 2; T and P appliance for running the tube in and out by hand when desired; 0 arrangement for bringing whole apparatus back for repair, &c.; M and N sluice-valve and handle; R, r', r 2 'r' 3, for draining tubes before torpedo is put in; X indicator showing position of inner tube.

Torpedoes have been discharged from this apparatus with successful result from a ship steaming at 172 knots.

Missing image
Torpedo-3.jpg

The advantage of cordite over compressed air for impulse is that it requires no attention: when a charge Gun FIG. 3. - Broadside Submerged 18-in. Torpedo Tube.

discharge. From the earliest days of the weapon this has been employed to some extent. But it was principally in the direction of right-ahead fire, by having an orifice in the stem of the ship under water, to which a torpedo tube was connected. The tactical idea was thus to supplement attack with the ram, so that if the vessel endeavouring to ram saw that the object would evade this attack, she could project a torpedo ahead, which, travelling faster than the vessel, might as effectually accomplish the required service. The stem orifice had a water-tight cover, which was removed on the torpedo being placed in the tube and the inner door closed; then, sufficient impulse being imparted to eject the torpedo, and its machinery being set in motion at the same time, it darted forward towards the enemy. There is, however, some risk of the ship using a torpedo in this manner striking it before the missile has gathered the necessary impetus from its propellers to take it clear of the vessel. The system, moreover, has the disadvantage of weakening the ram, the construction of which should be of immense strength. There is the further liability of ramming with a torpedo in the bow tube, which would be as disastrous to friend as foe. This method of submerged discharge has therefore given place to ejecting the torpedo from the broadside. Considerable difficulty attached to getting the torpedo clear of the ship from this position without injury, especially when the vessel was proceeding at speed. The natural tendency of the passing water acting on the head of the torpedo as it emerged was to give a violent wrench and crush the rear end before that portion could clear the aperture. To prevent this the torpedo must be hel-1 rigid in the line of projection until the tail is clear of the ship. This is thus effected. Besides the tube with the aperture in side of the ship under water, fitted with sluice-valve, all broadside submerged discharge apparatus possess the following features: A shield is pushed out from the ship's side. In this shield there are grooves of some form. Guides on the torpedoes fit and run in these grooves. When discharged the torpedo is thus supported against the streams of passing water, and guided so that its axis continues in the line of projection until the tail is clear of the side, the shield being of such length that this occurs at the same time that the guides on the torpedo leave the grooves in the shield. An apparatus on this principle has been fitted to a number of ships of the British navy, and gives good results at high rates of speed. It has the defect that the shield must be run out previous to the torpedo being discharged, and brought back afterwards, thus involving three separate operations, each performed by compressed air.

In the broadside submerged discharge, designed, constructed and supplied to many foreign navies by Messrs Armstrong of the Elswick works, the three operations are combined in one. There is an outer tube as before, but it contains an inner tube carrying the torpedo. Fized to this tube, and prolonging it, is the shield fitted with grooves. Both tubes have a door at the rear - made airtight when closed - by which the torpedo is entered. A charge of cordite is used for ejection instead of compressed air, the gas from which entering the outer cylinder first forces the inner tube out, and then by means of a valve in the door of the inner tube passes in and blows out water and torpedo together, the shield supporting the latter until the tail is clear of the ship. By this time the cordite gas has expanded and cooled so as to relieve the pressure in rear; this causes the pressure of the water outside to push the shield is placed in the explosion chamber, and a torpedo is in the tube, all is in readiness for firing when desired, without further attention in the torpedo-room. The cordite is fired by electricity from the conning-tower; the officer, therefore, having ascertained that all is ready below, has only to press a button when the object is in the required position. Automatic indications are given in the conningtower when the sluice-valve is opened and when all is in readiness for firing.

This method of discharging torpedoes from the broadside under water eliminates the principal danger of the system, which required the shield to be put into position beforehand. It was then liable to be struck and distorted by passing wreckage without the fact being apparent to those in the ship. On the discharge of a torpedo its course might thus be arrested, or possibly the charge be prematurely exploded in dangerous proximity to its own ship. There was a risk of getting the shield out too soon, and thereby exposing it unduly to injury, or leaving the operation until too late. The tendency of naval equipment being towards complication, any readjustment which makes for simplicity cannot be otherwise than beneficial, and this feature is especially desirable in all matters connected with the use of torpedoes.

The compartment containing the broadside submerged apparatus usually extends across the ship, so as to contain a tube for each side.

Use in War. - This has been mainly confined to attacks upon squadrons and single ships by torpedo craft of various types. At the battle of Yalu, between the Chinese and Japanese fleets, torpedoes were discharged by the former, but none took effect. The Japanese trusted solely to gun-fire. After the defeat of the Chinese at sea, their remaining ships took refuge in the harbour of Wei-hai-Wei. Here they were blockaded by the Japanese fleet, which, having a number of torpedo-boats, made several determined attacks upon the ships inside. After one or two attempts, foiled by the obstructions placed by the Chinese to bar the passage, the Japanese boats succeeded in torpedoing several ships, and thus expedited the reduction of the place. In the war between Spain and the United States the inferiority of Admiral Cervera's squadron to that under Admiral Sampson might at the battle of Santiago have been to some extent counterbalanced by a skilful and vigorous use of torpedoes. If, instead of striving only to escape, a bold dash had been made for the American ships, the Spanish cruisers rapidly approaching end on to the foe, enveloped in the smoke of their own guns, should - some at least - have got within torpedo range without fatal injury. Closing each other at a speed of ro knots only they would cover an interval of 6000 yds. in 9 minutes - a short time in which to disable a ship by gun-fire under such conditions. But Cervera elected to offer a passive resistance only, and while suffering destruction wrought no material injury upon his opponents. On the other hand, there have been several instances of large warships being sunk by locomotive torpedoes discharged from small craft. During the Chilean revolutionary war of 1891, a battleship, the "Blanco Encalada," of 3 500 tons, was attacked in Caldera Bay by two torpedo vessels - the "Lynch" and "Condell" - of 750 tons. They entered the bay at dawn, the "Condell" leading. This vessel fired three torpedoes which missed the ironclad; then the "Lynch," after one ineffective shot, discharged a second torpedo, which struck the "Blanco" on the side nearly amidships. The latter had opened fire with little result, and sank soon afterwards. A similar incident occurred in 1894, when the Brazilian ironclad "Aquidaban" was sunk in Catherina Bay by the "Sampaio"- a torpedo vessel of 500 tons. She entered the bay at night, and first discharged her bow torpedo at the ironclad, which missed; she then fired a broadside torpedo, which struck and exploded against the bow of the "Aquidaban." It caused a great shock on board, throwing an officer on the bridge into the water. The vessel sank soon afterwards, and the "Sampaio" escaped uninjured.

In the war (1904-5) between Russia and Japan the Whitehead torpedo did not exercise an important influence upon the naval operations. It scored a success at the beginning of the struggle when a Japanese torpedo-flotilla made an attack upon the Russian fleet lying at anchor outside Port Arthur. For some unaccountable reason, though war was imminent, little or no precautions seemed to have been taken for effectually guarding the vessels. They had no nets in position nor boats patrolling outside them. Thus taken by surprise when the Japanese torpedo-boats suddenly appeared about midnight on the 8th of February 1904, several Russian ships were struck by torpedoes before they could offer any resistance. The most damaged were the "Retvisan" and "Tsarevitch" (battleships) and "Pallada" (cruiser), but all managed to get into Port Arthur and were eventually repaired. With three ships hors de combat the Russian fleet was considerably weakened at an early stage. The loss of the "Petropavlovsk" in April from a mine explosion was a further discouragement, especially as with this ship went down the gallant and energetic Admiral Makarov. In these circumstances the Russian fleet could not assume the offensive nor prevent the Japanese troops being sent by sea to invest Port Arthur. In June when the injured vessels were fit for service again the fleet put to sea but returned the same evening. The incident is noteworthy only because it led to an attack by the Japanese torpedo craft on the retiring squadron after sunset. As illustrating the uncertainty of hitting a moving object at sea with the Whitehead torpedo, already mentioned, no vessels were struck on this occasion and they reached the anchorage uninjured. In the battle of Tsushima the Japanese torpedo-boats attacked the Russian fleet after its disablement by gun-fire and gave the coup de grace to some of the ships, which had little power of resistance owing to the destruction of their light armament. This war, therefore, did not increase to any extent our knowledge of the actual capability of this weapon.

Effect upon Naval Tactics: Blockade

It has often been assumed that steam and the torpedo will in future render blockade impossible as it was carried out in the old wars; that, no longer dependent upon the wind to allow egress from the blockaded port, a vessel using steam can emerge when she chooses, while the fear of torpedo attack will deter a blockading squadron from keeping such watch as to foil the attempt. As regards the power conferred by steam, it will be no less advantageous to a blockading squadron, enabling it to maintain its position, whereas sailing ships were often driven by gales to leave their station and seek a port. This gave opportunities for the blockaded vessels to escape. As regards torpedo-boats, they would no doubt be a danger to a blockading squadron unprovided with a means of defence against these craft. Such defence consists in an adequate number of small vessels interposing an in-shore squadron between the port and the main body outside. Thus they perform the twofold service of watching the enemy's movements within and frustrating a torpedo attack. As an instance of blockade under modern conditions, we have that of Admiral Sampson upon Santiago - a guard more rigidly maintained than any in the old wars. So little was he deterred by the knowledge that Admiral Cervera had two torpedo vessels in his force, that he drew his squadron closer in at night when an attack might be expected, actually illuminating the, entrance of the harbour with his electric searchlights, so that no craft could come out unperceived. No attempt was made to dislodge him from that position, and we may assume that blockade, if required in any scheme of naval strategy, will be carried out, whatever the weapons of warfare.

As regards the effect of torpedoes upon tactics at sea, and in general, as well as single ship, actions, they must operate against close range and employment of the ram. If it is recognized that a vessel within 1000 yds. is liable to a fatal blow, she will endeavour in ordinary circumstances to keep outside that distance and rely upon gun-fire. The exception would be where she is overmatched in that respect, and hence might endeavour to restore the balance by the use of torpedoes. In a fleet action the danger of missing a foe and hitting a friend would restrict the discharge of torpedoes; and this risk increases as formations disappear. But the torpedo must be conceded a tactical superiority over the ram for the following reasons: A vessel to use the latter must come within torpedo range, while her adversary may successfully apply torpedoes without placing herself in any danger of being rammed. The ram can only be used in one direction, and a small miscalculation may cause disaster. If a vessel has more than one position from which torpedoes can be discharged, she is not confined as regards attack to a single bearing or direction.

In action we may consider the speed of the torpedo as double that of the ship, and since against a moving object allowance must be made for the space traversed while ram or torpedo is travelling towards it, the faster weapon is less affected in its chance of successful impact by change of direction and speed of the object at the last moment. Lastly, with machinery disabled a ship is powerless to use the ram, but can avert a ram attack with her torpedoes. The movements of squadrons or single ships on entering an action are not likely to be influenced by any contemplated immediate use of torpedoes, for the gun must remain the primary weapon, at any rate at the first onset. Commanders would hardly risk being crushed by gun-fire before getting within torpedo range. Having faith in the efficiency of their ordnance and the gunnery skill of their crew, they would first manoeuvre to bring these into play. Tactics for torpedo attack in such circumstances have not therefore been laid down, and it is only necessary to consider the positions which are advantageous for the use of this weapon, and, conversely, what should be avoided when a vessel, finding herself overmatched in gunnery, seeks to redress the balance with torpedoes.

Size of Target

This, with a ship, varies in length as the torpedo approaches end on to the vessel, or at angle to the line of keel; the greatest being when the path of both forms a right angle. Hence the object is to pace your ship where it presents the former condition to the enemy, while he affords the larger target. It must be remembered that, owing to the comparatively slow velocity of the torpedo, it must be aimed not directly at a ship in motion - like a shot from a gun - but at a point ahead which the ship will reach after the torpedo has traversed the intervening distance. Thus speed of object has to be estimated, and hence the importance of adding to the velocity of the torpedo and getting a broadside shot so as to reduce as much as possible errors of calculation. The great increase of the dimensions of warships, especially in length, which now has reached 500 ft., adds to the chances of a successful hit with torpedoes, and will doubtless tend to diminish a desire in future naval tactics to close inside torpedo range for the purpose of ramming.

Range

Though the effective range of a torpedo discharged from a ship or torpedo vessel against a single object moving at high speed may be considered as approximately within woo yds. this limit of distance is considerably augmented where the target consists of several vessels at sea in close order, or is that afforded by a fleet at anchor. In the first case it may be worth while to discharge torpedoes from a distance of two or three thousand yards at the centre of the line for the chance of hitting one of the vessels composing it. As regards a mass of ships at anchor, unless protected by an impenetrable guard such as a breakwater or some invulnerable defence carried by the ships themselves, the increased range and accuracy of the torpedo imparted by recent developments would give it a chance of success if discharged against such a target at even greater distance.

Finally, by improvements in construction and methods of charge the torpedo has recovered the place it was rapidly losing a few years ago. As armour receives increased resisting power to above-water projectiles, and gets on a level again with the gun, more attention will be given to under-water attack, against which no adequate protection has yet been devised. Thus we shall probably find the torpedo taking a very prominent place in any future war between the great maritime powers. (S. M E.-W.)


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Wiktionary

Up to date as of January 15, 2010

Definition from Wiktionary, a free dictionary

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German Wikipedia has an article on:
Torpedo

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See also torpedo

German

Noun

Torpedo m. (genitive Torpedos, plural Torpedos)

  1. torpedo

Wikispecies

Up to date as of January 23, 2010

From Wikispecies

Taxonavigation

Main Page
Cladus: Eukaryota
Supergroup: Unikonta
Cladus: Opisthokonta
Regnum: Animalia
Subregnum: Eumetazoa
Cladus: Bilateria
Cladus: Nephrozoa
Cladus: Deuterostomia
Phylum: Chordata
Subphylum: Vertebrata
Infraphylum: Gnathostomata
Classis: Chondrichthyes
Subclassis: Elasmobranchii
Superordo: Rajomorphii
Ordo: Torpediniformes
Familia: Torpedinidae
Genus: Torpedo
Species: †T. acarinata - T. adenensis - T. alexandrinsis - T. andersoni - T. bauchotae - T. californica - T. fairchildi - T. formosa - T. fuscomaculata - T. mackayana - T. macneilli - T. marmorata - T. microdiscus - T. nobiliana - T. panthera - T. peruana - †T. pessanti - T. puelcha - T. semipelagica - T. sinuspersici - T. suessii - T. tokionis - T. torpedo - T. tremens

Name

Torpedo Duméril, 1806

References

Vernaculer names

Ελληνικά: Μάργα, Μαργωτήρα, Μουδιάστρα
English: Electric rays, Torpedoes

Simple English

The torpedo, is an explosive projectile weapon that moves by itself (using a propeller), launched above or below the water surface, that goes underwater toward a target, and made to explode when it hits a target or is near to it. Torpedoes may be launched from submarines, surface ships, helicopters, aircraft, etc.

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