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Posted on 12/21/2003 5:08:19 AM PST by snippy_about_it
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 are acknowledged, affirmed and commemorated.
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 The Early Days Ancient history tells us of the use of fire ships and powder ships against fleets of hostile vessels. It remained for Captain David Bushnell, U.S. Navy, to make use of this idea shortly before the American Revolution in the invention of a floating keg-mine. Captain Bushnell's "keg" was loaded with a small charge of gun powder, fired by the pulling of a lanyard led from the keg to the shore. The keg was floated down stream until it fouled the target, when the lanyard was pulled and the explosive charge set off. The Torpedo fish is an electric ray capable of delivering a stunning shock to its prey and in the eighteenth century an American, David Bushnell, first applied the name to a weapon of his invention. This first torpedo was simply a mine which was attached to the hull of a ship and exploded either by remote control or by a clockwork fuze. The name was also applied to floating mines and even blazing barrels of pitch carried into harbours by the tide. Within this general application of the name the history of the torpedo up to about 1860 is synonymous with the history of the mine. In order to give a continuous account of the torpedo's development we will go back to Roman days and note the use of fireships to destroy enemy fleets. The use of drifting weapons of destruction, powered by the ocean currents, is not so very far removed from destructive weapons powered by other means as in the present understanding of the name “torpedo”. The next stage in the sophistication of sea weapons appears in 1585 when the Italian Zambelli destroyed a bridge by means of a drifting boat loaded with explosives which were detonated by a clockwork delay fuze. We next find David Bushnell on the scene again with his submarine, Fig. 1. This remarkable one manpower vessel actually once sank a ship. The operation of the boat is quite obvious from the diagram. The operator used both hands and feet to control the forward and vertical motion by means of screws as well as operating a footpump and rudder.  FIG. 1. Bushnell's Boat (1775). The "torpedo" was a charge of explosive fixed to a ship's hull by means of the woodscrew illustrated and ignited by delayed action fuze. The operator then cranked himself furiously away from tile area before the "torpedo" exploded. The best documented attack by a Bushnell boat was made against the flagship of the British fleet sent to quell the unruly colonists towards the latter end of the eighteenth century. The submarine was successfully positioned under the ship but the woodscrew failed to penetrate the copper sheathing recently introduced onto the hulls of British warships.  Robert Fulton, another American, developed Bushnell's submarine into a more workable version named Nautilus. With this boat he sank several ships during demonstrations but was not very successful in selling his submarine to the American Navy. Working successively with the French against the British, with the British against the French and finally with the Americans against allcomers, he appears to have been a brilliant inventor and an opportunist. A very glamorised account of Fulton's machinations at the end of the eighteenth century appeared on B.B.C. television in the 1960's as a children's adventure series. Fulton must however be credited with the development of the submarine and its weapon, the mine, to a point where it could be used in wartime.  Soon after Fulton's work the name "Torpedo" became applied to a new class of weapons and the development of the mine continued on its own separate path. This new weapon was the Spar Torpedo Boat. Many forms of Spar Torpedo were used, particularly during the American Civil War. Nearly all types were basically the same and consisted of a steam launch having an explosive charge mounted at the end of a long pole projecting ahead of the boat. Fig. 2 shows a typical form as used by the Royal Navy around the 1880's. The launch carried a small crew one of whom viewed the external world through a steel conning tower. The launch approached an enemy ship under cover of darkness and placed the explosive charge against the ship's side and detonated it electrically.  FIG. 2. British Spar Torpedo Boat. The spar torpedo was quite successful and one of the most successful types was the "David" boat operated by the Southern States in the American Civil War. These carried a 60 lb charge on the end of a 25 ft long pole and the explosion was set off 6 ft below the waterline. A crew of eight was used and the boat ran awash. Indeed, it was fitted with hydroplanes for brief dives but these were often fatal. Although spar torpedoes were extensively used by the Americans, French, Russians and Chinese, the British considered them "unsporting" and were late introducing them. Indeed, the spar torpedo arrived in Britain just as the automobile torpedo as we think of it today was entering service and the spar torpedo then soon went into a decline in popularity. The spar boat was easily hit by gunfire and therefore became unpopular. As a result the automobile or "fish" weapon was invented and I shall now begin the story of the weapon known universally as the Torpedo. Whitehead's Flash of Genius  Robert Whitehead was born at Bolton in 1823, the son of the owner of a cotton-bleaching business. He was apprenticed at 14 to an engineer and there after travelled widely throughout Europe showing the way to improve silk-weaving machinery. In 1856 he became manager of an Austrian engineering company, Stabilimeno Technico Fiumano. The company was heavily engaged in providing engines for the Austrian Navy which was at war with Italy. It was through Whitehead's connections with the Navy that he was approached by a Captain Giovanni Luppis who had an idea for controlling a spar torpedo boat remotely by two ropes strung out from the tiller. Whitehead built a model but decided that the idea was not viable. He did however start to think about the problem of setting off explosive charges remotely below a ship's waterline-this being far more effective than above water bombardment. In 1866 his ideas took shape in the form of the first automobile torpedo. The weapon was built with the help of Whitehead's 12 year-old son and an old workman. The exact form of this first weapon is not known because Whitehead never revealed drawings even many years later and refused to describe the machine to inquirers. Eyewitness accounts describe it as blunt nosed "like a dolphin" with four long fins extending almost along the whole body length. The engine was driven by compressed air stored at 370 p.s.i. and regulated to approximately constant speed by a simple valve. The engine is generally described as a twin cylinder Vee but this probably refers to the later models of 1868. The original engine was based on two eccentric cylinders having a sliding vane to divide the volume into two parts. In this fashion the air pressure caused direct rotation of the outer cylinder which was coupled to the single propeller. The weapon was designed to be fired from an underwater tube and a constant depth was aimed at by means of a hydrostatic valve acting directly on the elevator controls. Azimuth control was simply by means of trim tabs set by trial and error over a 400 yards range at Fiume. The weapon achieved about six and a half knots to 200 yards and a further 100 yards at lower speed. The propeller speed on this first weapon was about 100 r.p.m. The depth keeping on this first weapon was very erratic. Within two years two new weapons had been produced which incorporated a device to be known for decades afterwards as "The Secret." This consisted of a hydrostat-pendulum combination after the fashion of Fig. 3. The simple hydrostat controlled depth according to the law d2D/dx2 is proportional to D0-D where D0 is the set depth and x is the distance run. Such a control law has no inherent damping and as a result the original weapon oscillated wildly. The introduction of the pendulum by means of the lever system illustrated introduced an additional term in the above equation proportional to pitch angle which is very nearly proportional to depth rate. Thus a damping term has been introduced. The depth errors were found to reduce from +/-40 ft to as little as +/-6 in. Such was the success of Whitehead's "Secret" that it remained in use virtually unchanged until the end of World War II, a remarkable tribute to a great Victorian engineer.  FIG. 3. Pendulum-Hydrostat depth gear of early torpedoes. In 1868 Whitehead demonstrated two new models before representatives of the Austrian Navy; a 14 in and a 16 in type. The weapons carried wet gun-cotton warheads and achieved speeds of about seven knots to about 700 yards. Fig. 4 shows the probable form of these early weapons. The propeller is shrouded to prevent damage and a large azimuth control vane is at the rear. These two features were soon to disappear however.  FIG. 4. Probable form of Whitehead Torpedo (1868). The Austrian Naval Officers attending the trials were impressed sufficiently to order weapons to be produced but were unable to buy the patent rights outright. British Torpedoes Enter Service In the autumn of 1869 Royal Navy representatives visited Fiume and reported favourably on the weapons being tested. As a result Whitehead was invited to England to demonstrate the ability of his weapons. He brought two types of torpedo with him, a 16 in. by 14 ft. carrying 67 lbs. of wet gun-cotton and a second weapon of 14 in. diameter and a little under 14 ft. in length. This latter weapon carried a warhead of dynamite weighing 18 lbs. The weapons were fired either from the surface or from a submerged tube built by Whitehead into Oberon. Over 100 firings were made during September and October of 1870, the average weapon performance being seven knots to a range of 600 yards. As a grand finale a wooden coal hulk was moored off Cockleshell Hard and surrounded with protective nets. A 16 in. weapon with its warhead charged by Professor F. A. Abel was fired from a range of 134 yards. The weapon, determined to demonstrate its potency, went around the net and blew a hole measuring 20 ft. by 10 ft. in the old corvette and it sank at once. Faced with such conclusive evidence of the weapon's capability the Royal Navy ordered a batch of Whitehead torpedoes which were received in 1870. It was most appropriate therefore that one century later a new torpedo trials ship should have been launched with the name E.T.V. Whitehead. Two types of weapon were received from Whitehead's works at Fiume; these being 14 in. and 16 in. diameter. In 1871 the Admiralty bought the manufacturing rights for £15,000 and production was started at the Royal Laboratories, Woolwich the following year. This sum of money seems very small for such an important weapon especially when only a decade later a certain Mr. Brennan was paid nearly 10 times as much for the rights of an inferior type of torpedo. The example of the Royal Navy was quickly followed by the French, Germans and Chinese and soon Whitehead was exporting his torpedoes around the world. Several countries started building their own pirated copies of the Whitehead but these were notably unsuccessful. The stringent specifications laid down by foreign navies caused Whitehead to give consideration to the improvement of performance. He appears to have regarded the weapon as primarily for use in harbours against moored ships. Under these circumstances a speed of only seven knots is acceptable and the main areas for improvements lie with the accuracy of steering and the reliable operation of the impact fuse. However, the Germans specified a weapon performance of 16 knots to 550 yards. Whitehead carried out various improvements including the replacement of the twin cylinder Vee engine by a three-cylinder engine built by Peter Brother-hood, Ltd., of Peterborough. Thus by 1875 a 14 in. weapon was produced having a performance of 18 knots to a range of 550 yards. In 1872 Whitehead bought the firm and re-named it Silurifico Whitehead. A remarkable feature of this story is the instant success of the novel weapon. The very first experimental torpedo worked well and was being mass produced for export within four years. With the introduction of the new engine and contrarotating propellers (this latter by a foreman mechanic at Woolwich) no significant improvements were then made until the introduction of the gyroscope for azimuthal steering in 1895. Fig. 5 shows the transitional form of the weapon in about 1875. The extended fins thereafter were not needed because of the lack of roll forces. Fig. 5 shows typical Fiume built torpedoes of the 1880s period with their pointed noses and small control fins with the control surfaces placed aft of the propellers. This latter feature distinguished Fiume weapons from the Woolwich types (Fig. 6) which carried the surfaces ahead of the screws. The latter practice persists (unfortunately) to the present time.  FIG. 5. A selection of Fiume weapons (c1874-1880).  FIG. 6. R.G.F. Weapons (c1894). Weapons of various types were produced during the first few decades of the life of the automobile torpedo. In particular, many obscure types of unorthodox propulsion were produced in the United States, as we shall see. The Whitehead type did not however undergo significant charge although many new Mark numbers were introduced. The Germans, in addition to ordering Whitehead torpedoes in 1873, began building their own on the Whitehead principle. The firm of L. Schwartzkopf-later the Berliner Maschinenbau A.G.-began making excellent torpedoes in phosphor-bronze. The firm was soon exporting weapons to Russia, Japan and Spain. In 1885 Britain ordered 50 of these weapons because the output at home and at Fiume could not satisfy the demand. These weapons cost £450 each which was £120 more than the corresponding Fiume type (the 14 in. Mk. II). The 14 in. by 11 ft. weapon was built originally to the specification of the Russians who wanted a minimum speed output of 20 knots. This was achieved and all Whitehead weapons exceeded this speed from this time. The speed improvements were made by increasing the inlet pressure to the engine (with consequent improvements to engine details) and a corresponding increase in air vessel pressure. By 1882 the vessels were being built to withstand at least 1,500 p.s.i. and Britain led the world in the construction of bronze pressure vessels. Figures for weapon range were not reliable up to this time because range was not an important parameter. Ranging at Fiume was carried out from an underwater tube aimed at a net 400 yards distant. The maximum running distance was only measured when requested by a customer. After all, the chance of hitting a ship decreases rapidly with range because of the errors inherent in the weapon and the aiming process so that there was little point in firing a torpedo at a range greater than about 400 yards even if the weapon was capable of greater range. At about this time the Italians built their own version of a Fiume torpedo but it ran at only 7 knots. Whitehead rebuilt it and it achieved 20 knots. As a result the Italians gave up building their own weapons and bought from Whitehead. In external appearance the various weapons were very similar. The torpedoes were often built up with standard tail and nose sections but with different middle sections. These composite torpedoes each carried different mark numbers but were in fact very similar in performance. In 1883 a committee, set up to examine various aspects of torpedo design, carried out trials to test whether the nose shape had any effect on weapon speed. The pointed nose was assumed to cleave the water best but the great hydrodynamicist Dr. Froude advised that blunt head should show no disadvantage in speed performance and would allow much larger warheads to be carried. Comparative trials were carried out using the Mk W Fiume and R.L. Mk XI torpedoes each fitted with blunt and pointed noses. The tests showed that the blunt-nosed torpedoes had a full knot advantage over the pointed nosed version. This meant that heavier warheads could be carried without loss of propulsive performance and the ultimate in blunt nose designs during this period appeared in 1909 with the American hemispherical heads. Fig. 7 shows the development of the torpedo shape to the form (in 1912) from which few departures took place in the following four decades.  FIG. 7. Evolution of the Blunt Nose Torpedo. The United States had not taken advantage of the offers in 1869 and 1874 to manufacture Whitehead torpedoes under license and followed an independent and generally unsuccessful development programme of her own. Last Cold Compressed Air Whitehead Weapons Whitehead torpedoes were being manufactured at a considerable rate during the last 15 years of the 19th century. From Fiume the Silurifico Whitehead was sending hundreds of weapons around the world and many more were being manufactured under license in foreign countries or being simply pirated. The German Schwartzkopf firm were manufacturing about 400 weapons annually which were sent to Spain, Italy, China and Britain. It was soon after the mid-1880s that torpedo performance began to improve. This was largely as a result of competition from improved gunnery. Indeed, in 1904 the battle of Tsushima was settled by gunfire at a range of 6,000 yards and no torpedo could at that time compete with such performance. The torpedo's saving grace was its ability to deliver with stealth an explosive charge to the most vulnerable part of a ship. Torpedo range was increased by the introduction of the l8in. Whitehead weapon in 1888 but not by a very great amount; the advantage being taken rather to increase the size of warhead. Meanwhile at Woolwich torpedo performance improvements made the specially constructed canal too short and a new range was set up at Horsea Island in 1888 and 10 years later the Bincleaves range was set up near Weymouth. In 1890 Whitehead opened his factory at Weymouth which survived until recently under the ownership of Vickers, Armstrong Ltd. In 1893 the Royal Navy decided to transfer the torpedo works at the Royal Laboratories to the Royal Gun Factory (thus weapons became known as R.G.F. types) and as a result the Weymouth works did not get the British orders that were expected. Henceforth the Whitehead torpedoes produced at Weymouth were mostly sent for export to countries not able to manufacture their own. Similarly, Whitehead had opened a factory at St. Tropez at the same time as the Weymouth venture and this also exported to countries such as Brazil, Holland, Turkey and Greece. Some torpedoes from the Weymouth works did enter service with the Royal Navy especially during the 1914-18 war period. The last association of the works with the Royal Navy appears to have been in the early stages of the Mark 23 torpedo in the mid-1950s. Whitehead always regarded his torpedoes as primarily for launching from underwater tubes. The Royal Navy however 'seems to have favoured above-water firing devices. Under water tubes can be placed either in the bow where the ramming effectiveness of the ship is weakened (ramming was a most popular means of naval warfare in the 1 870s) or they can be placed across the ship for broadside shots. In the latter position the torpedo experiences a strong twisting force as it emerges due to the water flow along the ship. A device for overcoming this effect was invented by Capt. A. K. Wilson, V.C. and consisted of a guide bar projecting from the ship along which the emerging weapon slid until free of the disturbing effect of the ship's motion. Another device ejected a tube with the torpedo for a distance of several feet such that the water flow forces were taken by the tube and not the weapon. These devices were adopted by the British but were not generally popular. The first above water launching was made by sliding a l4in. weapon off a mess table out through a porthole and, having thus proved the feasibility of the scheme, several methods were evolved for launching weapons from a ship's deck. Most of the early methods consisted of a simple frame for holding the torpedo over the water and releasing it in approximately the right direction. Light torpedo boats used a frame which was lowered about 2ft. into the water for launching. The tube working on the pea shooter principle was invented in about 1880. The weapons were ejected by compressed air but within a few years the propelling gas was generated by slowburning gunpowder in granular form. This remained the method of tube launch for many decades; indeed the present deck-mounted tubes work on exactly the same scheme but with different propelling cartridges. The British method of discharging torpedoes from above the waterline was viewed with some concern by Whitehead. His son-in-law and partner, Count George Hoyo's, reported after a visit to Britain that "such delicate weapons are not meant to be fired like shot from a gun" but the weapons 'seemed to tolerate their rough treatment for in 1879 there were already 33 British warships fitted with launching equipment. Introduction of the Gyroscope In 1895 came the first significant improvement to the torpedo since its invention. Whitehead introduced the gyroscope for azimuth control using the type invented by an Austrian, Ludwig Obry. In this device a 1.75 lb. wheel some 3in. in diameter was held in gimbals with its axis along that of the torpedo. The wheel was spun up to maximum speed 2,400 r.p.m. by means of a pretensioned spring. The wheel reached this speed before the weapon left the tube so that the torpedo followed the aimed-for track in the water irrespective of the impulsive forces acting on hitting the water. This greatly improved the overall accuracy of firing and with the new device fitted it was possible to fire to an accuracy of ~ thus enabling a beam-on target to be hit at a range of about 7,000 yards-except that torpedoes at that time had ranges not exceeding 1,000 yards. This clearly provided a considerable impetus for torpedo designers to increase performance. The original Obry gyroscope wheel only contained a maximum of 20ft. - lbs. of energy. This had the effect of allowing the gyro to topple after an inconveniently short time of running. The toppling was induced by the fact that the gyroscope gimbals were required to directly operate a rudder servo control. Whitehead soon introduced an intermediate servo however which greatly reduced the forces acting on the gimbals and the way was then opened up for long range weapons. The version of the Obry gyroscope supplied to the United States was provided with an angling gear which enabled the weapon to change course after firing, thus giving greater flexibility in the firing procedure. This refinement was introduced into the Royal Navy in 1900. The turn of the century saw a radical change in torpedo design with the introduction of the heated, or steam torpedo. This is therefore an opportune time to study the torpedo development of nations, such as the United States, who did not adopt the Whitehead compressed air method of propulsion. Departures from Whitehead Principles The Torpedo Test Station was set up in 1870 at Rhode Island, U.S.A. to work on spar torpedoes but in 1871 an automobile torpedo was built, Fig. 8. This was built on the supposed lines of the Whitehead weapons and indeed the propulsive performance was similar, i.e. 7 knots to a range of 300 yards. The warhead was 70 to 90 lbs. of dynamite or guncotton. Here the similarity to the White-head torpedo ends for the American version refused to run a straight course. This is not surprising in view of the minimal control surface area provided. Another weapon was built in 1874 but this was no more successful. The air vessel was made of bronze in the latter case because no American firm would undertake to make a steel vessel of sufficient strength. The British were masters of the forging and rolling art for pressure vessels at this time. The Japanese had many failures in this respect and eventually bought their pressure vessels from England.  FIG. 8. First United States Automobile Torpedo. Having failed to produce a working automobile torpedo and having turned down two offers of the Whitehead plans the Torpedo Test Station set about building under the inventive eye of J. L. Lay, an officer in the U.S. Navy, a series of strange and generally unsuccessful weapons. Most of the weapons floated and thus did not have the ability to vary the striking depth at the enemy ship. The Lay torpedoes floated with only a few inches of hull showing and were controlled by an operator by means of electrical impulses sent down a wire. The power unit was a gas engine driven by compressed carbon dioxide and the steering impulses transmitted down the wire operated electromagnetic relays on the rudder. The position of the weapon was indicated by two flags or discs. Fig. 9 shows an early form of the Lay Torpedo as built in the 1870s. A later form used liquefied C02 as the power source with the liquid warmed in pipes external to the weapon. Still later we find the Lay-Haight weapon driven by gas generated by the action of sulphuric acid on lime. The later weapons had their propeller near the forward end of the hull partially recessed to avoid damage. It also avoided efficient propulsion!  FIG. 9. Lay Dirigible Weapon. These weapons were never really successful on account of their unreliability and vulnerability to gunfire. In a trial carried out off the British coast for the Royal Navy the Lay weapon heeled over badly so that the propeller was only half under the surface. Two Lay torpedoes were sold to the Peruvian Government for use in the war against Chile. In 1879 a Lay weapon was fired from the Peruvian ironclad Huascar at a Chilean ship. Half-way to the target the weapon turned around and "hurtled" at 15 knots back at the mother ship despite the frantic knob twiddling of the operator. The ship was saved by the heroic action of a ship's officer who swam out to intercept the weapon and deflect it. The relieved captain promptly took the two weapons to a local graveyard where they were buried only to be later exhumed by the Chilean rebels! The vulnerability of these weapons was overcome in the 'Patrick ' and 'Wood-Haight' 'torpedoes by suspending them beneath unsinkable floats. These floats were either wood or thin copper sheet cylinders containing water-proofed cotton waste. The floats could be shot again and again without sufficient buoyancy being lost to sink the weapon. The propulsion was by compressed carbon dioxide gas expanded through a gas engine-usually a three-cylinder Brotherhood type, similar to the version used extensively by Whitehead. The electric torpedo made its appearance in about 1873 with the Ericsson which was propelled by sending power down a cable unreeled from the weapon. A direct development of the Ericsson torpedo was the Sims-Edison which was similarly powered down a trailing wire. A speed of 10 knots was attained using a Siemens motor drawing 30 amps at 600 volts. Several versions of this weapon appeared, all carried under a large float and very similar in external appearance to the weapon of Fig. 10, and the last version built in 1889 carried a 4001b. warhead to a range of over two miles.  FIG. 10. Nordenfelt Wire-Guided Electric Torpedo. The Nordenfelt torpedo, illustrated in Fig. 10, was invented by the great Swedish engineer who also produced the first really successful submarine. Motive power was from a vast stack of batteries, the early version having 108 storage cells which produced 18 S.H.P. Guidance was by means of electrical impulses transmitted down a wire paid out from the weapon. A British intelligence report of the period described the early weapon as being supported by a wooden float and carrying one mile of guidance wire. The weapon described by Sleeman and illustrated in Fig. 10 was said to have been buoyant and held down by the heavy fins. It is difficult to see how this weapon could have remained upright. The sloping edge to the fin was supposed to assist the weapon to pass under torpedo nets. This weapon, the forerunner of the present generation of wire-guided electric torpedoes, achieved 16 knots to a range (for the later version) of two and a half miles. Superheated steam was a popular means of propulsion in the 1880s and the American 'Hall' torpedo was typical. Water at 5500F and under high pressure was fed directly from the boiler of the torpedoboat. Evaporation of the water under reduced pressure provided a propulsive performance comparable with con-temporary Whitehead models. None of these steam torpedoes reached the production stage. largely because of the lengthy preparation time required. Hall's weapon had a strange roll control system based on a transverse mercury-filled U-tube. Any rolling action of the weapon caused wings to be pushed in and out under the action of the mercury. The wings were angled to provide lift in such a fashion that the weapon maintained, in theory at least, an even keel. Another superheated water weapon, the Paulson, was kept on a straight heading by a mariner's compass in the nose. Electrical contacts on the compass could be set just before launch and the weapon followed that setting after launch.  FIG 11 Cunningham's Rocket Torpedo. Rocket propulsion has been often considered even up to the present time. One of the first automobile torpedoes built after the Whitehead model made its appearance was rocket propelled. Both the Weeks and the Ericsson rocket achieved about 40 to 60 knots to a range of 100 yards. Lt. F. M. Barber of the Naval Torpedo Station, Rhode Island, produced an underwater rocket in 1873. This was 7 ft. long by 1 ft. diameter and weighed 287 lbs. The warhead was 48 lbs. of gunpowder and the 51 lbs. of rocket fuel were stored inside a cast iron tube wrapped in asbestos and having an outer casing of oak! Mr. Cunningham, an American shoemaker, built rocket torpedoes and once celebrated the 4th July by setting off one of his torpedoes up the town's main street. It shot off at high speed scaring old ladies and horses and finally came to rest in the butcher's shop where it set fire to the icebox. The Berdan (sometimes called the Borden) was a rocket propelled floating torpedo which towed another small weapon. Fig. 12 shows how the rocket ower was converted to rotary power by means of a turbine acting on a set of propellers. When the Berdan struck the torpedo nets surrounding a ship the slackening of the towline caused the small weapon to go into a programmed dive under the nets and strike the ship under the keel in theory that is ! British intelligence reports of trials carried out before the Turkish Navy indicate that this weapon was not a success.  FIG. 12. Berdan Torpedo. Rockets were not the only alternative propulsion systems to challenge the conventional propeller drive. One torpedo invented during this period was propelled by an umbrella like contraption at the rear. This was operated by an oscillating shaft which opened and shut the "umbrella" and so propelled the vehicle rather in the fashion of a frog's foot! During WWII the Germans devised a torpedo propelled by a flapping wing. This was claimed to be at least as efficient as a conventional propeller and much quieter. The advantages of blunt noses on torpedoes might also have been realised earlier if the first torpedoists had studied the salmon. Only two torpedoes, apart from the White-head patterns, went into successful quantity production before the turn of the century. (The Lay weapon was exported to Russia for harbour defence work but only in small quantities). The Brennan torpedo was invented by an Australian watchmaker and was driven by pulling two 18 gauge piano wires out of the weapon. This was achieved by a steam winch mounted on the shore. The use of this torpedo from ships was ruled out by the need for a stable winch platform. The wires were unreeled from two drums inside the weapon and these directly drove the contrarotating propellers. Steering was achieved by varying the relative tension of the wires. This caused the weapon to heel over and a compensating pendulum applied steering control. Fig. 13 shows a later version of this weapon where the drums were on a common longitudinal axis. A depth control similar to that used by Whitehead was installed. The performance of the Brennan was 20 knots to a range of 3,000 yards-this being considerably better than the contemporary Whitehead weapon-and the range was only limited by the length of wire carried. The weapon was used exclusively for coastal defence by the Royal Engineers over a 20 years period around the turn of the century. The huge Brotherhood winches were installed in concrete blockhouses and the 'torpedoes were run down to the water on rails. The derelict remains of a Brennan torpedo station have been discovered on the Thames estuary.  FIG. 13. The Brennan Torpedo. A scandal blew up over the adoption of this torpedo when the Government paid Brennan no less than £110,000 for his invention and paid him a vast salary to act as production chief. Compare this sum with the miserable £15,000 paid for the manufacturing rights of the much more worthy Whitehead weapon only 15 years previous. Maxim, brother of the famous gun manufacturer, produced in the United States a wire-powered torpedo suspiciously similar to the Brennan except in the detail of depth keeping. The Maxim torpedo actually pumped water into or out of a ballast tank. Such fanciful devices are not confined to the last century. In 1944 a torpedo was built in Britain that varied its depth by pushing the main battery to and fro to alter the position of the centre of gravity. Finally we will consider the Howell torpedo which was the mainstay of the United States Navy for 20 years up to about 1895 and was a serious contender to the supremacy of the Whitehead torpedo outside the United States. Fig. 14 shows the appearance of the weapon and Fig. 15 shows the internal construction. The propulsive power was derived from a heavy flywheel and transmitted to twin propellers. The weapon was ship-launched from a tube and the flywheel was spun just prior to launching by a steam winch external to the launching tube.  FIG. 14. The Howell Flywheel Torpedo (1892).  FIG. 15. Howell Torpedo. A wheel speed of 12,000 r.p.m. was obtained in the later versions of the weapon and with a wheel weighing 130 lbs. this gave a weapon performance of 30 knots to 800 yards with a decreasing speed for a further 400 yards. This was comparable with the Whitehead weapons of the same period. This relatively good performance combined with simplicity of construction and operation resulted in the Whitehead torpedo not making its appearance in the United States until 1892. The Howell torpedo had three advantages over the Whitehead apart from simplicity. The weapon left no track, it did not vary its trim and. more important, it kept to a straight course. This latter was achieved by using the gyroscopic action of flywheel. Because the wheel axis was transverse any departure of the weapon from a straight line caused the weapon to heel over. This was detected by a transverse mounted pendulum which was directly connected to rudders which produced a correction to the course and hence a righting torque. This was in fact the first application of the gyroscope to torpedoes. When the Obry gyroscope was used in Whitehead torpedoes in 1895 Howell started a legal battle over patent rights. The above weapons were departures from the Whitehead compressed air principle but one weapon, again the brainchild of Ericsson, eliminated the heavy air vessel by supplying compressed air through an 800 ft. hose. The drag on the hose greatly slowed down the weapon however. Having taken the technical development of the torpedo up to the turn of the century we will finish this section with a look at the aggressive use of the weapon. The first sinking by a torpedo was during the Chilean revolutionary war. Two Birkenhead-built torpedo boats attacked the Blanco Encalada on the night of April 23rd, 1891. The first boat, Almirante Conte fired three Whiteheads at the ironclad but these all missed. The second torpedo boat, the Almirante Lynch fired another salvo of three weapons and one hit. The effect of the 58 lb. of guncotton in the 14 in. weapon was to blow a hole 15 ft. by 7 ft. below the waterline. The ship sank immediately with the loss of 180 officers and men. The ship had left her torpedo nets at port and the water-tight doors were not closed. One consequence of the explosion was the ejection of the Captain, Don Luis Goni, up a ventilation shaft and into the sea where he was later seen swimming ashore with one arm around the ship's mascot, a tame llama. The animal was then taken as mascot onboard H.M.S. Warspite until it was sent to the London Zoo in disgrace for eating the epaulettes off an Admiral's dress uniform! The Chinese had little success with their Schwartzkopf weapons in the war of 1894 largely because theirs were fired at very long ranges. Local fishermen recovered them from the beaches and sold them back to the Chinese for 100 dollars each. Such inefficiency is only to be expected from officers who pawned their ship's guns in the ports!      |
Here is my latest article in the chat section.
A Freeper's Observation: Our State Representatives At Their Dumbest And Most Idiotic.
The Harvard Underwater Sound Laboratory, HUSL, was a scientific base for the development of active and passive homing systems for torpedoes during WWII. The scientists at Harvard and other Labs researched and developed concepts for potential applications in the defense of our country. As reported in the January 1996 issue of the Navy Submarine Review, NSR, by this author and in the April 1996 issue of the NSR by Dr. Fred Milford, the passive acoustic homing concepts were developed and engineered at HUSL and at Bell Labs. The resulting product was produced by Western Electric, with assistance from General Electric, and became the first U.S. passive homing torpedo, MK24 (FIDO). There was an independent but cooperative effort between HUSL and Bell Labs. This passive homing system concept was then carried into many other passive homing torpedoes. HUSL also worked with General Electric, GE, in the development of the first active homing system for torpedoes.HISTORICAL BACKGROUND
DR Vanevar Bush suggested to President Roosevelt prior to US involvement in WWII that scientists and engineers be utilized to assist in advanced technology applications for the military. In June 1940, President Roosevelt appointed a group of eminent scientists to become part of the National Defense Research Council, NDRC with Dr. Bush as the chairman. In 1941, NRDC became part of the newly formed Office of Scientific Research and Development, OSRD. When Dr. Bush became director of the OSRD, Dr. Conant, President of Harvard, became the chairman of NRDC. Research laboratories were established at Universities, such as Harvard, Columbia, and Cal Tech at Pasadena. Top scientists, engineers, and technicians were hired to perform the needed research and development for military applications.
RESEARCH AND DEVELOPMENT
The role of a scientific laboratory to develop concepts, followed by engineering development by other Navy sponsored labs, and finally production by industry is still carried on today. The U. S. Navy has four University Laboratories: The Applied Physics laboratory at Johns Hopkins, founded in 1943; the Applied Research Laboratory at Penn State, founded in 1945 as the Ordnance Research Laboratory , ORL, with the transfer of HUSL personnel; the Applied Research Laboratories at University of Texas founded in 1945 as the Defense Research Laboratory with the transfer of HUSL personnel; and the Applied Physics Laboratory at the University of Washington founded in 1943. After HUSL closed its doors following the end of WWII, many of the HUSL torpedo scientists, engineers, and torpedo men transferred to Penn State to work at the formed Ordnance Research Lab and to the University of Texas to work at the Defense Research Lab. Dr. Eric Walker, Assistant Director at HUSL, moved to Penn State to become the head of the Electrical Engineering Department and at the Navy’s urging, formed the Ordnance Research Lab. Dr. Paul Boner, another Assistant Director at HUSL, returned to Texas and formed the Defense Research Lab. Each of the University labs have a different mission but maintain a cooperative effort since there may be over-lapping tasks.
The Navy provides funding to these laboratories to do ongoing research. This is performed as a preventative measure for future application of this accumulated scientific knowledge to answer potential threats posed by unfriendly countries. When there is a threat, the Navy puts out an Operational Requirement to meet the threat. The University Laboratories respond with their accumulated knowledge base coupled with assistance from other Navy Laboratories to provide an answer to the threat. After the conceptual system is formulated and prototype tested by the University Laboratories, it is then available for contractual bidding by Industry. The Laboratories assigned to carry on the supervision of developmental engineering are largely the Navy Laboratories, such as the Naval Underwater Weapons Centers, NUWC, at Newport, R.I. and at Keyport, WA. However, the University laboratories and the Navy labs will generally have some degree of involvement until after production and Follow-on Test and Evaluation. There is a variable degree of overlap. Navy funding categories for fundamental research and initial development are 6.0, 6.1, and 6.2. Prototypes were initially funded by 6.2 money , but today, prototype development is funded by 6.3 money. Developmental work today is by category 6.3 and production is funded by category 6.4. However, as in the mission assignments, there is some overlap.
The feasibility of these concepts is tested in prototype torpedoes as Harvard and Bell Labs had done with the Mk 24 torpedo tests. Torpedo development is one of the missions of the Applied Research Laboratory at Penn State. ARL has been involved in the research and development of most torpedoes in the Fleet today with the exception of the Mk 46 torpedo homing system which was developed by the Naval Torpedo Station at Pasadena, CA (later NOSC, San Diego),
ACTIVE HOMING STUDIES
In addition to the passive homing studies at HUSL and Bell Labs under Navy Project NO-94 during WWII, active homing studies were being performed at HUSL and at General Electric, GE under Navy Project N0-181F. The active homing objective under Navy Project N0-181F was to obtain greater detection range through the use of higher directivity and a reduction of self-noise. Self-noise reduction was a challenging task and required comprehensive and experiments. The Mk 18 with electric propulsion was an initial test platform for several homing systems. Other self noise reduction came about through solving ground loop problems, crosstalk between wires, and harmonics.
HUSL scientists and GE engineers each worked on an active homing system, called echo ranging. They encountered much difficulty until they learned more about the of the environment and were able to cope with the resulting acoustic problems. It was difficult for the early active homing systems to distinguish among echoes from the target and the echoes from the bottom, surface, and sealife. In addition , the vertical direction of the echo is confused by refractive properties resulting from thermal differences in the water and by reflections from the boundaries, surface and bottom. Also, horizontal steering at close-in terminal homing ranges is confused since multiple echoes were received from different sections of the target, such as the bow, stern and sail. At long ranges, the entire target is acoustically ensonified and appears as a point source. However, as the range gets very short, multiple echoes appear from several sections of the target and this confuses the active homing system’s horizontal steering. Today’s’ torpedoes are still faced with this problem but have more complex circuitry to provide more accurate horizontal steering.
The Mk 18 with its electric propulsion was one of the torpedoes being fitted with the active homing systems. The major problem, addition to learning the environmental effects, was the internal noise level of the torpedo.
These active acoustic homing torpedoes may be categorized into first generation consisting of the Mk32, Mk 35, Mk 37, Mk 43, and the Mk44 torpedoes. The second generation may include the Mk 46 and Mk 48 torpedoes. The third generation would consist of the Mk 48 ADCAP and the Mk 50 torpedoes. Research work at the laboratories leads to improvements in existing torpedoes with advancements in computers and other technologies. For example, some of the transistors used in the Mk 48 are no fleet longer available so new electronic parts replace them as needed.
MK 32 TORPEDO
The first active homing torpedo in the Fleet was the Mk 32 torpedo. It was an antisubmarine torpedo launched from aircraft and surface ships. It was developed by GE with some combined and competitive effort between HUSL and GE. The Mk 32 torpedo’s homing system was only active and did not have a passive homing capability. The Mk 32 torpedo was about the size of the Mk 24 (FIDO) passive homing torpedo. It was 83 inches long, 19 inch diameter, 700 pound weight, electric propulsion, warhead of 107 pounds HBX, 12 knot speed, and a range 9600 yards(24 minutes). GE had discarded its crystal transducers in favor of the HUSL magnetostrictive transducers.
Eventually, successful demonstrations of active homing were made by GE during June 1943 in the azimuth plane with the Mk 32 prototype. It would be in early February 1944, before the Mk 32 prototype demonstrated a successful homing attack on a target in three dimensions. Since GE did not have available facilities for production, Leeds and Northrup of Philadelphia was awarded the production contract. However, ten torpedoes were produced during WWII and none saw action.
There was some limited active homing work in a developmental torpedo designated the Mk 22. Bell Labs and Westinghouse experimented with active acoustics in the azimuth plane for terminal homing. This work was discontinued in favor of the planned Universal Torpedo to be designated as the Mk 35.
The Ordnance Research Lab in a combined effort with GE continued post war development of the Mk 32 Mod 2 torpedo. About 3300 torpedoes were produced by the Philco Corp. in Philadelphia and the Naval Ordnance Plant in Forest Park, IL. This torpedo saw service from 1950 to 1955, when it was replaced by the Mk 43 torpedo.
The evolution of active homing systems continued at ORL and at GE. ORL pursued the concepts of the Navy Project NO-181 F, designating the work as ORL Project 4 while GE pursued a different approach. These two lines of effort resulted in two distinct types of active homing systems.
MK 35 TORPEDO
As noted earlier in this article, the Navy requested that work begin on a Universal type torpedo with an active homing system. GE was given the contract. The Navy wanted an active homing torpedo capable of being launched from aircraft, surface ship, or submarine. The Mk 35 was the first generation deep diving, long range, acoustic torpedo designed to attack submerged submarines.
The Mk 35 torpedo was based on the acoustic homing system performances of the homing torpedoes Mk 24 and Mk 32. It was originally designed as the Universal Torpedo capable of being launched from any type of platform. During development, the torpedo grew to 162 inches and 1770 pounds eliminating it from aircraft use. It had a 21 inch diameter with a electric propulsion system featuring a seawater battery. It was planned to have an active capability, passive capability, and used a spiral search pattern. It had a speed of 27 knots and a range of 15 kyds. The Mod 1 version reportedly failed OPEVAL. A Mk 35 Mod 2 torpedo was built with a re-designed homing system based on work at GE and ORL.
Between 1949 and 1952, GE at Pittsfield, MA built 400 units which saw limited service. It was withdrawn from further development and production in favor of the Mk 37 torpedo. The research, development, and testing of this torpedo had cost between 14 and 15 million dollars.
HOMING SYSTEM DESIGNS
The evolution of the active homing systems from HUSL continued in 1945 at ORL (now ARL) and GE resulted in two distinct active homing systems. Both homing systems measured the target echo in terms of the leading edge rise time, amplitude, and echo length relative to the transmitted pulse. However, the HUSL/ORL design had a Doppler Gate which separated the echoes based on Doppler of greater than 1.2 knots allowing a greater sensitivity to the amplitude detection of echoes from targets. The Doppler gate provided the first viable Doppler classification method of distinguishing targets from false alarms. This had the adverse effect of not detecting very Low Doppler targets, but had the positive effect of significantly reducing the amount of false alarms from reverberation.One of the designers remembers using a capacitor to slope the front edge of the transmitted pulse to obtain a narrower reverberation spectrum. It was the beginning of what we call today ‘Pulse Weighting or Waveform Shaping’. A square pulse would have a wider reverberation spectrum whereas an amplitude modulated pulse would have a much narrower reverberation spectrum. Also, the reverberation spectrum was also dependent on the length of the transmitted pulse. The narrower the pulse, the wider the reverberation spectrum. The wider reverberation spectrum made it difficult to detect Doppler targets. The GE system, without the Doppler gate, could detect the lower Doppler targets, but was subject to a high false alarm rate.
The ORL transducer design provided a transformer for impedance coupling between the transmitter and transducer which resulted in a greater efficiency, whereas the GE design dumped the power directly into the mis-matched transducer impedance resulting in a loss of transmit power.
In addition, during transmit, the HUSL/ORL design provided the simultaneous driving of all four sectors of the transducer array. During the receive mode, the transducer produced outputs from four quadrants with different phase centers. The phase differences among these signals indicated the three dimensional direction of the arrival of the echo. The input circuit converted these voltages to four in-phase voltages of varying amplitude. The amplitude differences between corresponding pairs gave target angle information simultaneously in the horizontal and vertical planes. This allowed the torpedo to boresight on the target during attack. The GE system used a similar transducer with upper and lower halves rather than the four quadrants. Therefore, GE’s system would provide directional steering in the vertical plane, but the horizontal steering was a “steeraway” technique. The torpedo searched by circling until it received a target detection , then in it reversed the turn until the target was lost . This meant that the steering on the target was held at the side of the horizontal beam rather on boresight.
The processing of signals was a problem with receivers using an amplifier to process each signal from the transducer sectors. It was difficult to maintain the same gain in each amplifier. The HUSL/ORL receiver design addressed this problem by using a single amplifier. The four voltages produced by the input circuit were used to amplitude modulate a 1 khz carrier. This signal was passed through a single channel amplifier. The average amplitude of the modulated signal was a measure of the received echo amplitude, the phase of the modulation envelope was an indication of target angle information, and the amplitude of the modulation envelope was a function # of both the echo amplitude and the angle between the direction of echo arrival and the transducer axis.
MK 37 TORPEDO
The ORL/HUSL active homing system design was selected for the Mk 37 torpedo and the contractor was Westinghouse at Sharon, PA. ORL’s Nick Abouresk was the Liaison and Project Manager for the technical direction of ORL’s active homing system implementation into the Mk 37 torpedo. The earlier HUSL design was modified by replacing the larger vacuum tubes with miniature vacuum tubes and much attention was given to packaging, stability, and electronic noise reduction. The operating frequency was 60 KHZ and the propulsion was a two speed electric motor. This torpedo was the first fleet torpedo to have active and passive homing capabilities throughout the run. It was 135 inches in length, 19 inch diameter, 1430 pounds, warhead of 330 # HBX-3, and used a contact exploder. It had a nominal detection and homing range of about 700 yards. This torpedo which was produced in quantities of over 3300 units at the Naval Ordnance Park at Forest Park, IL served as the U.S. Navy’s primary submarine acoustic torpedo from the mid-1950’s until the Mk 48 torpedo replaced it in the early 1970’s.
Since the Mk 37 torpedo had electric propulsion, it would swim out of the torpedo tube instead of being impulsed thereby reducing the launch transients and the detectability of the launching submarine. Wire guide was later added to the torpedo making it 26 inches longer and 230 pounds heavier. The submarine fire control was also modified to take advantage of the wire guide capabilities.
After replacement of the Mk 37 in the U.S. Fleet by the Mk 48, the Mk 37 torpedo was sold to several countries. Today, the Mk 37 torpedo is being used by many countries, including Israel. However, the vacuum tubes in the homing systems of the original versions have been replaced by solid state electronics. U.S. firms, such as Alliant Tech and Westinghouse, have contracts to modify and service these torpedoes.
MK 43 TORPEDO
As stated earlier, the Mk 32 torpedo was discontinued in favor of the Mk 43 torpedo. The Mk 43 Mod 0 was developed and produced by GE at Pittsfield, MA. It was an inexpensive lightweight air-drop torpedo. After 500 of these units were built, they were discontinued in favor of the Mk 43 Mod 1 and Mk 43 Mod 3 torpedoes.
The Naval Ordnance Test Station, NOTS, Pasadena, CA and the Brush Development Co., Cleveland, OH developed the Mk 43 Mod 1 with a 10 inch diameter, 91.5 inch length , 260 # weight, warhead of 54HBX, active homing with a helical search pattern, and a 15 knot speed and a range endurance of about 4500 yards. Brush Electronics, Cleveland, OH and the Naval Ordnance Park, Forest Park, IL produced 5000 of these torpedoes until they were replaced by the Mk 44 torpedo. It was the first lightweight torpedo capable of being launched from helicopters, fixed wing aircraft, and surface ships. The Mk 43 torpedo was in the Fleet from 1951 to 1957 and was replaced by the Mk 44 torpedo. The Mk 43 torpedoes were sold to the British and perhaps other countries.
MK 44 TORPEDO
The Mk 44 Mod 0 torpedo was a replacement for the Mk 43 torpedo with improvements in speed, warhead size, acoustic homing changes, and pre-launch programmable search modes. It was developed by NOTS, Pasadena, CA and GE, Pittsfield, MA. It was the first air launched fleet torpedo with a seawater-activited battery to provide power. It was produced at GE and later at the Naval Ordnance Plant, Forest Park, IL. It was in service from 1957 through 1967 on destroyers and aircraft as an ASW weapon until it was replaced by the torpedo Mk 46. The Mk 44 torpedo was sold to foreign governments and also produced in Europe by NATO countries.
MK 46 TORPEDO
The Mk 46 was developed by Aerojet General, Azusa, CA and NOTS, Pasadena. It was the first air launched deep diving, high speed ASW torpedo with active/passive homing and represents the second generation in airborne ASW weaponry. It entered the fleet in 1965 and went through several modifications, from Mod 0 through Mod 5. The Mod 1 version was 102 inches long, a diameter of 12.75 inches, weight of 508 pounds, speed of 40 knots, range of 12,000 yards. The Mod 4 version is also capable for use in mine systems, such as Captor.
The Mk 46 Mod 5 torpedo was built based on the studies Near-Term Improvement Program, NEARTIP, and resulted in improvements in acoustic performance in deep and shallow water, counter measure resistance, guidance and control, and the fire control system. A driving force for this NEARTIP torpedo was to respond to the anechoic coatings on Soviet submarines. The MK 46 Mod 5 is primarily an ASW weapon and can be launched from surface ships, fixed-wing aircraft, helicopters, ASROC, and mine systems. According to Jane’s book, about 20,000 Mk 46 torpedoes were built for US and foreign use. funded It is estimated that the US fleet may have at least 13,000 Mk 46 torpedoes in its inventory. More current torpedo modifications will provide significant improvements as the advances in computer and electronic technologies continue. It has not been replaced despite the new advanced Mk 50 torpedo primarily due to cost and reduction of the threat. Jack Slaton , (who worked at ORL, NOSC, Alliant Tech, and is now retired) was one of the chief designers of the Mk 46 homing system and was a major contributor to the Mk 50 homing system.
MK 48 TORPEDO & ADVANCED TORPEDOES
As torpedo technology improves because of research at University and Navy laboratories, these weapons are greatly improved and this in turn provides the submariner with a higher probability of success. The Mk 48 torpedo , which replaced the Mk 37 torpedo in submarines will be discussed in a future issue of the Navy Submarine Review. Also slated for future publication will be the Mk 48 ADCAP and the Mk 50 torpedoes. There is not sufficient article space to discuss these weapons in this article.
INFORMATION COLLECTION AND REVIEW
I would like to thank all those who have provided information which helped me to assemble this article on the early active homing systems in torpedoes and the events leading to the development of these torpedoes. Re-construction of history and publication of events can be very rewarding, leading to many favorable comments as well as a few dissenting opinions. All these are appreciated unless written in a hostile tone. It takes a considerable time and dedication to research and write this article for your enjoyment .
I would appreciate any information you might have on the development of the Mk 48 torpedo that may be included in my next article.ADDRESS: Tom Pelick
609 Berkshire Drive
State College, PA 16803tpelick@psu.edu
Not a bad day. My Vikings won yesterday and my family is on the way to bring in some of what Santa brought them.
And....Mr. Cunningham, an American shoemaker, built rocket torpedoes and once celebrated the 4th July by setting off one of his torpedoes up the town's main street. It shot off at high speed scaring old ladies and horses and finally came to rest in the butcher's shop where it set fire to the icebox. Those were exciting days!
The advantages of blunt noses on torpedoes might also have been realised earlier if the first torpedoists had studied the salmon. But WHY is the blunt nose more effiecient and faster than the pointy-ends?
'Morning, Snippy! Fascinating history lesson today!
Can you imagine? It's like being shot out of a cannon. LOL.
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