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96-560: Work on what would become the Tunnan commenced in late 1945. The design, internally designated R 1001 , had a barrel-like fuselage, giving it a distinctive rotund appearance, from which its name is derived. A relatively thin swept wing configuration was adopted after wartime aerodynamic research from Germany indicated its favourable high speed qualities. It was powered by the recently-developed de Havilland Ghost turbojet engine. The Swedish Air Force placed an initial order for three prototypes under

192-583: A Saab 29 prototype was on 1 September 1948, was made by S/L 'Bob' Moore, who was later the first managing director of Saab GB, UK . A problem with the landing gear affected the expected top speed of the aircraft. Following the flight, Moore described the aircraft as "on the ground an ugly duckling – in the air, a swift." Because of the shape of its fuselage, the Saab J 29 quickly received the nickname Flygande Tunnan ("The Flying Barrel"), or Tunnan ("The Barrel") for short. While not appreciated by SAAB, its short form

288-461: A compressive force on neighboring atoms, and smaller atoms exert a tensile force on their neighbors, helping the alloy resist deformation. Sometimes alloys may exhibit marked differences in behavior even when small amounts of one element are present. For example, impurities in semiconducting ferromagnetic alloys lead to different properties, as first predicted by White, Hogan, Suhl, Tian Abrie and Nakamura. Unlike pure metals, most alloys do not have

384-466: A gaseous state, such as found in a blast furnace to make pig iron (liquid-gas), nitriding , carbonitriding or other forms of case hardening (solid-gas), or the cementation process used to make blister steel (solid-gas). It may also be done with one, more, or all of the constituents in the solid state, such as found in ancient methods of pattern welding (solid-solid), shear steel (solid-solid), or crucible steel production (solid-liquid), mixing

480-588: A hard bronze-head, but a softer bronze-tang, combining the alloys to prevent both dulling and breaking during use. Mercury has been smelted from cinnabar for thousands of years. Mercury dissolves many metals, such as gold, silver, and tin, to form amalgams (an alloy in a soft paste or liquid form at ambient temperature). Amalgams have been used since 200 BC in China for gilding objects such as armor and mirrors with precious metals. The ancient Romans often used mercury-tin amalgams for gilding their armor. The amalgam

576-551: A larger engine. The resulting design was known as the Venom , and shared many features with the earlier Vampire. The Ghost first flew in the Venom on 2 September 1949. By this point the engine had been running for some time and was already at the Mk.103 model of 4,850 lbf (21.6 kN). The Venom was used primarily as a fighter bomber , although some were also produced as night fighters . The Venom

672-446: A molten metal is mixed with another substance, there are two mechanisms that can cause an alloy to form, called atom exchange and the interstitial mechanism . The relative size of each element in the mix plays a primary role in determining which mechanism will occur. When the atoms are relatively similar in size, the atom exchange method usually happens, where some of the atoms composing the metallic crystals are substituted with atoms of

768-433: A molten metal may not always mix with another element. For example, pure iron is almost completely insoluble with copper. Even when the constituents are soluble, each will usually have a saturation point , beyond which no more of the constituent can be added. Iron, for example, can hold a maximum of 6.67% carbon. Although the elements of an alloy usually must be soluble in the liquid state, they may not always be soluble in

864-455: A more concentrated form of iron carbide (Fe 3 C) in the spaces between the pure iron crystals. The steel then becomes heterogeneous, as it is formed of two phases, the iron-carbon phase called cementite (or carbide ), and pure iron ferrite . Such a heat treatment produces a steel that is rather soft. If the steel is cooled quickly, however, the carbon atoms will not have time to diffuse and precipitate out as carbide, but will be trapped within

960-405: A pioneer in steel metallurgy, took an interest and produced a steel alloy containing around 12% manganese. Called mangalloy , it exhibited extreme hardness and toughness, becoming the first commercially viable alloy-steel. Afterward, he created silicon steel, launching the search for other possible alloys of steel. Robert Forester Mushet found that by adding tungsten to steel it could produce

1056-429: A single melting point , but a melting range during which the material is a mixture of solid and liquid phases (a slush). The temperature at which melting begins is called the solidus , and the temperature when melting is just complete is called the liquidus . For many alloys there is a particular alloy proportion (in some cases more than one), called either a eutectic mixture or a peritectic composition, which gives

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1152-420: A very hard edge that would resist losing its hardness at high temperatures. "R. Mushet's special steel" (RMS) became the first high-speed steel . Mushet's steel was quickly replaced by tungsten carbide steel, developed by Taylor and White in 1900, in which they doubled the tungsten content and added small amounts of chromium and vanadium, producing a superior steel for use in lathes and machining tools. In 1903,

1248-480: A way to harden aluminium alloys for use in machine-gun cartridge cases. Knowing that aluminium-copper alloys were heat-treatable to some degree, Wilm tried quenching a ternary alloy of aluminium, copper, and the addition of magnesium, but was initially disappointed with the results. However, when Wilm retested it the next day he discovered that the alloy increased in hardness when left to age at room temperature, and far exceeded his expectations. Although an explanation for

1344-576: Is a metal. This is usually called the primary metal or the base metal, and the name of this metal may also be the name of the alloy. The other constituents may or may not be metals but, when mixed with the molten base, they will be soluble and dissolve into the mixture. The mechanical properties of alloys will often be quite different from those of its individual constituents. A metal that is normally very soft ( malleable ), such as aluminium , can be altered by alloying it with another soft metal, such as copper . Although both metals are very soft and ductile ,

1440-761: Is extremely slow thus the penetration was not very deep, so the alloy was not homogeneous. In 1740, Benjamin Huntsman began melting blister steel in a crucible to even out the carbon content, creating the first process for the mass production of tool steel . Huntsman's process was used for manufacturing tool steel until the early 1900s. The introduction of the blast furnace to Europe in the Middle Ages meant that people could produce pig iron in much higher volumes than wrought iron. Because pig iron could be melted, people began to develop processes to reduce carbon in liquid pig iron to create steel. Puddling had been used in China since

1536-473: Is hydraulically operated, and was designed to be suitable for use from rough airstrips. To improve pilot survivability, the Tunnan used an ejection seat Saab developed in 1943, with an explosive jettisoning system for the canopy. The Tunnan is powered with a single 22.4 kN (5,000 lb f ) de Havilland Ghost turbojet which have a top speed in excess of 1,050 km/h (650 mph), better performance than Sweden's de Havilland Vampires . The engine

1632-400: Is performed by heating the base metal beyond its melting point and then dissolving the solutes into the molten liquid, which may be possible even if the melting point of the solute is far greater than that of the base. For example, in its liquid state, titanium is a very strong solvent capable of dissolving most metals and elements. In addition, it readily absorbs gases like oxygen and burns in

1728-471: Is prevented (forming martensite), most heat-treatable alloys are precipitation hardening alloys, that depend on the diffusion of alloying elements to achieve their strength. When heated to form a solution and then cooled quickly, these alloys become much softer than normal, during the diffusionless transformation, but then harden as they age. The solutes in these alloys will precipitate over time, forming intermetallic phases, which are difficult to discern from

1824-646: The Rolls-Royce Avon engine which was to be used in the Comet 2. Several versions of the Ghost 50 were produced, ending with the Ghost 50-Mk.4 installed in the Comet 1XB which was built to test new fuselage construction techniques introduced to address problems with the Comet 1. During development, the Royal Air Force also asked for an improved version of the de Havilland Vampire with greater load-carrying capacity and thus

1920-458: The Saab 21R , had been modified from the piston-engined Saab 21 . It is a small, chubby aircraft with a single round air intake in the nose, with the pilot under a bubble canopy directly above the air intake duct on the upper-forward section of the fuselage. It has a very thin mid-mounted moderately swept two-spar wing which is a single structure attached to the fuselage by four bolts. The undercarriage

2016-560: The Wright brothers used a chromium-nickel steel to make the crankshaft for their airplane engine, while in 1908 Henry Ford began using vanadium steels for parts like crankshafts and valves in his Model T Ford , due to their higher strength and resistance to high temperatures. In 1912, the Krupp Ironworks in Germany developed a rust-resistant steel by adding 21% chromium and 7% nickel, producing

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2112-611: The bloomery process , it produced very soft but ductile wrought iron . By 800 BC, iron-making technology had spread to Europe, arriving in Japan around 700 AD. Pig iron , a very hard but brittle alloy of iron and carbon, was being produced in China as early as 1200 BC, but did not arrive in Europe until the Middle Ages. Pig iron has a lower melting point than iron, and was used for making cast-iron . However, these metals found little practical use until

2208-906: The secessionist's Fouga Magisters since they were unarmed. The only aircraft lost was by a high-ranking officer who crashed during an aborted takeoff for a test flight. When ONUC ended in 1964, some of the Swedish aircraft were deliberately destroyed at their base, as they were no longer needed in Sweden, having been superseded by later variants, and the cost of returning them wasn't justified. Saab R 1001 Saab 29 A Saab 29 B Saab 29 C Saab 29 D Saab 29 E Saab 29 F Data from The Great Book of Fighters, The Saab J 29 J 29F pilots manual General characteristics Performance Armament Aircraft of comparable role, configuration, and era Related lists De Havilland Ghost The de Havilland Ghost (originally Halford H-2 )

2304-408: The solid state. If the metals remain soluble when solid, the alloy forms a solid solution , becoming a homogeneous structure consisting of identical crystals, called a phase . If as the mixture cools the constituents become insoluble, they may separate to form two or more different types of crystals, creating a heterogeneous microstructure of different phases, some with more of one constituent than

2400-730: The 1970s. In August 1976, the last official military flight was performed at the Swedish Air Force's 50th anniversary air show. On 27 January 1961, the Swedish Government authorized the Air Board to sell 15 J 29F Tunnans to Saab for restoration and resale to the Austrian Air Force . Like the Swedish counterpart, the Saab 29 came to be colloquially called “flying barrel” ( Fliegende Tonne ) or just “barrel” ( Tonne ) in Austria. In 1962,

2496-453: The American 75S aluminium alloy , Svenska Metallverken was able to manufacture it, although significantly larger sections were used than typical for aircraft construction. The structure employed heavy frames and stressed skin to meet conflicting requirements on space, strength, rigidity and accessibility. The Swedish Air Force requested verification of the performance and a production plan for

2592-403: The Comet or Venom was ready for flight. By this point the Ghost had been selected for the Swedish "JxR" fighter project, which eventually turned into the Tunnan. During the design of the Tunnan, Sweden received German data on swept wing designs via Switzerland and redesigned the plane to incorporate this planform. The Tunnan first flew in this form in 1948. For production versions of the Tunnan,

2688-596: The F 22 Wing of the Swedish Air Force , were stationed in the Republic of Congo as Sweden's contribution to a UN peacekeeping mission ( ONUC ). They were subsequently reinforced by four more J 29Bs and two S 29C photo reconnaissance Tunnans in 1962. The Tunnans received UN identifying markings on their fuselages. Most missions involved attacking ground targets with cannons and unguided rockets but no aircraft were lost in action despite heavy ground fire . The consensus of

2784-550: The Ghost was built under licence by Svenska Flygmotor (later to become Volvo Aero) as the RM2 . The Ghost was also licence built in Italy by Fiat and in Switzerland by Sulzer Brothers . The Ghost would next be seen when the Comet I first took to the air on 27 July 1949. It was powered by the 5,000 lbf (22 kN) Ghost 50, which was the interim powerplant, pending the availability of

2880-495: The Goblin's sixteen smaller ones, using bifurcated "split intakes" which were fed by each diffuser duct to effectively make twenty inlets. While the prototype was being built, de Havilland bought Halford's firm and reformed it as the de Havilland Engine Company , renaming the H-1 and H-2 as the Goblin and Ghost respectively. The Ghost was running in 1944, and flew in 1945. This was long before

2976-400: The J 29 prototypes could exceed the maximum Mach number for which they had been designed and flight performance figures were typically in excess of predicted values. Quantity production commenced in 1948; during May 1951, Bråvalla Wing (F 13) received the first production aircraft. The Tunnan was produced in five main variants. The J 29A fighter was the first model to enter service, and

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3072-670: The Mediterranean, so it was often valued higher than gold. To make jewellery, cutlery, or other objects from tin, workers usually alloyed it with other metals to increase strength and hardness. These metals were typically lead , antimony , bismuth or copper. These solutes were sometimes added individually in varying amounts, or added together, making a wide variety of objects, ranging from practical items such as dishes, surgical tools, candlesticks or funnels, to decorative items like ear rings and hair clips. The earliest examples of pewter come from ancient Egypt, around 1450 BC. The use of pewter

3168-565: The Middle East, people began alloying copper with zinc to form brass. Ancient civilizations took into account the mixture and the various properties it produced, such as hardness , toughness and melting point, under various conditions of temperature and work hardening , developing much of the information contained in modern alloy phase diagrams . For example, arrowheads from the Chinese Qin dynasty (around 200 BC) were often constructed with

3264-533: The Saab design team, led by Lars Brising . The first of these, codenamed R 101 , nicknamed cigarren (the cigar) due to its shape, bore a strong resemblance to the American Lockheed P-80 Shooting Star . The second design, which was chosen, was the barrel -shaped design, codenamed R 1001 , which proved to be both faster and more agile. The R 1001 concept had a straight wing, but after the engineers obtained German swept wing research data, it

3360-516: The aerospace industry, to beryllium-copper alloys for non-sparking tools. An alloy is a mixture of chemical elements , which forms an impure substance (admixture) that retains the characteristics of a metal. An alloy is distinct from an impure metal in that, with an alloy, the added elements are well controlled to produce desirable properties, while impure metals such as wrought iron are less controlled, but are often considered useful. Alloys are made by mixing two or more elements, at least one of which

3456-414: The air, readily combines with most metals to form metal oxides ; especially at higher temperatures encountered during alloying. Great care is often taken during the alloying process to remove excess impurities, using fluxes , chemical additives, or other methods of extractive metallurgy . Alloying a metal is done by combining it with one or more other elements. The most common and oldest alloying process

3552-596: The aircraft approached the sound barrier." To make the wing as thin as possible, the undercarriage retracted into the fuselage, rather than the wings. Wind tunnel testing at the Swedish Royal University of Technology and by the National Aeronautical Research Institute also influenced its aerodynamics. These tests determined the required fuselage form to ensure it could attain the targeted critical Mach number , as well as supporting

3648-420: The alloy a unique and low melting point, and no liquid/solid slush transition. Alloying elements are added to a base metal, to induce hardness , toughness , ductility, or other desired properties. Most metals and alloys can be work hardened by creating defects in their crystal structure. These defects are created during plastic deformation by hammering, bending, extruding, et cetera, and are permanent unless

3744-429: The alloy. However, most alloys were not created until the 1900s, such as various aluminium, titanium , nickel , and magnesium alloys . Some modern superalloys , such as incoloy , inconel, and hastelloy , may consist of a multitude of different elements. An alloy is technically an impure metal, but when referring to alloys, the term impurities usually denotes undesirable elements. Such impurities are introduced from

3840-444: The atomic arrangement that forms the alloy. They can be further classified as homogeneous (consisting of a single phase), or heterogeneous (consisting of two or more phases) or intermetallic . An alloy may be a solid solution of metal elements (a single phase, where all metallic grains (crystals) are of the same composition) or a mixture of metallic phases (two or more solutions, forming a microstructure of different crystals within

3936-635: The base metal. Unlike steel, in which the solid solution separates into different crystal phases (carbide and ferrite), precipitation hardening alloys form different phases within the same crystal. These intermetallic alloys appear homogeneous in crystal structure, but tend to behave heterogeneously, becoming hard and somewhat brittle. In 1906, precipitation hardening alloys were discovered by Alfred Wilm . Precipitation hardening alloys, such as certain alloys of aluminium, titanium, and copper, are heat-treatable alloys that soften when quenched (cooled quickly), and then harden over time. Wilm had been searching for

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4032-554: The base metals and alloying elements, but are removed during processing. For instance, sulfur is a common impurity in steel. Sulfur combines readily with iron to form iron sulfide , which is very brittle, creating weak spots in the steel. Lithium , sodium and calcium are common impurities in aluminium alloys, which can have adverse effects on the structural integrity of castings. Conversely, otherwise pure-metals that contain unwanted impurities are often called "impure metals" and are not usually referred to as alloys. Oxygen, present in

4128-426: The carbon atoms are said to be in solution in the iron, forming a particular single, homogeneous, crystalline phase called austenite . If the steel is cooled slowly, the carbon can diffuse out of the iron and it will gradually revert to its low temperature allotrope. During slow cooling, the carbon atoms will no longer be as soluble with the iron, and will be forced to precipitate out of solution, nucleating into

4224-600: The civilian Prague-Ruzyně airport. One machine lost its landing gear on landing, the other overturned on a ditch, the pilot was trapped and had to be rescued by people working in the field. Both pilots were returned to their homeland after two days. The planes followed them later by rail. The Tunnan was the first Swedish jet aircraft to see combat. In response to an appeal by the United Nations (UN) for military support in September 1961, an initial force of five J 29Bs organized as

4320-414: The crews and foreign observers was that the Tunnan's capabilities were exceptional. Their secessionist adversaries used a few Fouga Magisters and other aircraft with no air combat capabilities. Swedish pilots refused some requests for close air support to ground troops, reasoning that the risk of civilian casualties was too high. In November 1962, the Swedish air commander refused a direct order to destroy

4416-502: The crystals internally. Some alloys, such as electrum —an alloy of silver and gold —occur naturally. Meteorites are sometimes made of naturally occurring alloys of iron and nickel , but are not native to the Earth. One of the first alloys made by humans was bronze, which is a mixture of the metals tin and copper. Bronze was an extremely useful alloy to the ancients, because it is much stronger and harder than either of its components. Steel

4512-427: The elements via solid-state diffusion . By adding another element to a metal, differences in the size of the atoms create internal stresses in the lattice of the metallic crystals; stresses that often enhance its properties. For example, the combination of carbon with iron produces steel, which is stronger than iron, its primary element. The electrical and thermal conductivity of alloys is usually lower than that of

4608-455: The emergency pair, who had to stay at the airport. The Austrian pilots thus got deep into the interior of the country and after finding that they had fuel for about the last 2 minutes of the flight, the pilots, believing that the field on which they landed was solid enough, landed in a field in the area of the village of Ořech in the Prague-West district. Coincidentally, just a few kilometres from

4704-466: The first airplane engine in 1903. During the time between 1865 and 1910, processes for extracting many other metals were discovered, such as chromium, vanadium, tungsten, iridium , cobalt , and molybdenum, and various alloys were developed. Prior to 1910, research mainly consisted of private individuals tinkering in their own laboratories. However, as the aircraft and automotive industries began growing, research into alloys became an industrial effort in

4800-416: The first century, and was introduced in Europe during the 1700s, where molten pig iron was stirred while exposed to the air, to remove the carbon by oxidation . In 1858, Henry Bessemer developed a process of steel-making by blowing hot air through liquid pig iron to reduce the carbon content. The Bessemer process led to the first large scale manufacture of steel. Steel is an alloy of iron and carbon, but

4896-499: The first stainless steel. Due to their high reactivity, most metals were not discovered until the 19th century. A method for extracting aluminium from bauxite was proposed by Humphry Davy in 1807, using an electric arc . Although his attempts were unsuccessful, by 1855 the first sales of pure aluminium reached the market. However, as extractive metallurgy was still in its infancy, most aluminium extraction-processes produced unintended alloys contaminated with other elements found in

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4992-400: The form of a high-manganese pig-iron called spiegeleisen ), which helped remove impurities such as phosphorus and oxygen; a process adopted by Bessemer and still used in modern steels (albeit in concentrations low enough to still be considered carbon steel). Afterward, many people began experimenting with various alloys of steel without much success. However, in 1882, Robert Hadfield , being

5088-474: The interstices, but some of the iron atoms are substituted by nickel and chromium atoms. The use of alloys by humans started with the use of meteoric iron , a naturally occurring alloy of nickel and iron. It is the main constituent of iron meteorites . As no metallurgic processes were used to separate iron from nickel, the alloy was used as it was. Meteoric iron could be forged from a red heat to make objects such as tools, weapons, and nails. In many cultures it

5184-551: The introduction of crucible steel around 300 BC. These steels were of poor quality, and the introduction of pattern welding , around the 1st century AD, sought to balance the extreme properties of the alloys by laminating them, to create a tougher metal. Around 700 AD, the Japanese began folding bloomery-steel and cast-iron in alternating layers to increase the strength of their swords, using clay fluxes to remove slag and impurities. This method of Japanese swordsmithing produced one of

5280-405: The iron crystals. When rapidly cooled, a diffusionless (martensite) transformation occurs, in which the carbon atoms become trapped in solution. This causes the iron crystals to deform as the crystal structure tries to change to its low temperature state, leaving those crystals very hard but much less ductile (more brittle). While the high strength of steel results when diffusion and precipitation

5376-518: The lack of a two-seat, dual control Tunnan trainer variant: this meant that Swedish fighter pilots could only be trained using two seat variants of the de Havilland Vampire (a straight-winged jet), before going solo in a Tunnan. 99 pilots were killed during military practice flights in Sweden. In May 1967, the fighter versions of the Tunnan was retired from combat service; however, a number of aircraft were retained and reconfigured for use as countermeasures trainers and for target towing duties into

5472-450: The metal is recrystallized . Otherwise, some alloys can also have their properties altered by heat treatment . Nearly all metals can be softened by annealing , which recrystallizes the alloy and repairs the defects, but not as many can be hardened by controlled heating and cooling. Many alloys of aluminium, copper, magnesium , titanium, and nickel can be strengthened to some degree by some method of heat treatment, but few respond to this to

5568-485: The metal). Examples of alloys include red gold ( gold and copper ), white gold (gold and silver ), sterling silver (silver and copper), steel or silicon steel ( iron with non-metallic carbon or silicon respectively), solder , brass , pewter , duralumin , bronze , and amalgams . Alloys are used in a wide variety of applications, from the steel alloys, used in everything from buildings to automobiles to surgical tools, to exotic titanium alloys used in

5664-416: The more capable J 29B and J 29E fighters, and finally the afterburner -equipped J 29F fighter, which was the final fighter variant to be built. A dedicated aerial reconnaissance model, the S 29C , was also operated. During the 1960s, several J 29Bs saw combat while stationed in the Republic of Congo as Sweden's contribution to a UN peacekeeping mission ( ONUC ). The Austrian Air Force also operated

5760-455: The ore; the most abundant of which was copper. These aluminium-copper alloys (at the time termed "aluminum bronze") preceded pure aluminium, offering greater strength and hardness over the soft, pure metal, and to a slight degree were found to be heat treatable. However, due to their softness and limited hardenability these alloys found little practical use, and were more of a novelty, until the Wright brothers used an aluminium alloy to construct

5856-418: The other constituent. This is called a substitutional alloy . Examples of substitutional alloys include bronze and brass, in which some of the copper atoms are substituted with either tin or zinc atoms respectively. In the case of the interstitial mechanism, one atom is usually much smaller than the other and can not successfully substitute for the other type of atom in the crystals of the base metal. Instead,

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5952-416: The other. However, in other alloys, the insoluble elements may not separate until after crystallization occurs. If cooled very quickly, they first crystallize as a homogeneous phase, but they are supersaturated with the secondary constituents. As time passes, the atoms of these supersaturated alloys can separate from the crystal lattice, becoming more stable, and forming a second phase that serves to reinforce

6048-400: The phenomenon was not provided until 1919, duralumin was one of the first "age hardening" alloys used, becoming the primary building material for the first Zeppelins , and was soon followed by many others. Because they often exhibit a combination of high strength and low weight, these alloys became widely used in many forms of industry, including the construction of modern aircraft . When

6144-441: The presence of nitrogen. This increases the chance of contamination from any contacting surface, and so must be melted in vacuum induction-heating and special, water-cooled, copper crucibles . However, some metals and solutes, such as iron and carbon, have very high melting-points and were impossible for ancient people to melt. Thus, alloying (in particular, interstitial alloying) may also be performed with one or more constituents in

6240-495: The project in February 1946. In Autumn 1946, the Swedish Air Force formally ordered three prototypes, with the type designation J 29 . Static testing of the full-scale mock-up revealed problems with pressure cabin leaks, and concerning aileron behavior. A hydraulic system was installed to solve the latter issue. However, these modifications delayed the first flight until after the hoped for date of 1 August 1948. The first flight by

6336-636: The pure elements such as increased strength or hardness. In some cases, an alloy may reduce the overall cost of the material while preserving important properties. In other cases, the mixture imparts synergistic properties such as corrosion resistance or mechanical strength. In an alloy, the atoms are joined by metallic bonding rather than by covalent bonds typically found in chemical compounds. The alloy constituents are usually measured by mass percentage for practical applications, and in atomic fraction for basic science studies. Alloys are usually classified as substitutional or interstitial alloys , depending on

6432-415: The pure metals. The physical properties, such as density , reactivity , Young's modulus of an alloy may not differ greatly from those of its base element, but engineering properties such as tensile strength , ductility, and shear strength may be substantially different from those of the constituent materials. This is sometimes a result of the sizes of the atoms in the alloy, because larger atoms exert

6528-443: The purest steel-alloys of the ancient world. While the use of iron started to become more widespread around 1200 BC, mainly because of interruptions in the trade routes for tin, the metal was much softer than bronze. However, very small amounts of steel, (an alloy of iron and around 1% carbon), was always a byproduct of the bloomery process. The ability to modify the hardness of steel by heat treatment had been known since 1100 BC, and

6624-415: The rare material was valued for the manufacture of tools and weapons. Because the ancients could not produce temperatures high enough to melt iron fully, the production of steel in decent quantities did not occur until the introduction of blister steel during the Middle Ages. This method introduced carbon by heating wrought iron in charcoal for long periods of time, but the absorption of carbon in this manner

6720-612: The resulting aluminium alloy will have much greater strength . Adding a small amount of non-metallic carbon to iron trades its great ductility for the greater strength of an alloy called steel. Due to its very-high strength, but still substantial toughness , and its ability to be greatly altered by heat treatment , steel is one of the most useful and common alloys in modern use. By adding chromium to steel, its resistance to corrosion can be enhanced, creating stainless steel , while adding silicon will alter its electrical characteristics, producing silicon steel . Like oil and water,

6816-657: The sale of a further 15 J 29F aircraft to Austria was authorized. This second batch was modified so a camera pod could be installed in the port side of the nose of each aircraft, which required the removal of two cannons. The interchangeable camera pod could be exchanged in roughly 30 minutes, and the cameras could be redirected in flight from the cockpit. Due to the limitations of the 1955 Austrian State Treaty , these were never armed with air-to-air missiles . The Tunnan remained in Austrian Air Force service until 1972. On 20 October 1964 at 9:48 a.m., two Austrian J 29Fs, of

6912-428: The same degree as does steel. The base metal iron of the iron-carbon alloy known as steel, undergoes a change in the arrangement ( allotropy ) of the atoms of its crystal matrix at a certain temperature (usually between 820 °C (1,500 °F) and 870 °C (1,600 °F), depending on carbon content). This allows the smaller carbon atoms to enter the interstices of the iron crystal. When this diffusion happens,

7008-466: The second fighter bomber wing ( 2. Staffel/JaBo-Geschwader ), took off from the base in Linz; the first, Bu. No. 29559 "E", was piloted by Sergeant Johan Kemetinger, the second, Bu. No. 29627 "L", was piloted by Staff Sergeant Alfred Erdler. In bad weather and a radio beacon mix-up, the pilots "smoked" and crossed the airspace of the then Czechoslovakia. Due to the bad weather, they could not even be intercepted by

7104-404: The service designation J 29 during Autumn 1946. On 1 September 1948, the first prototype performed its maiden flight ; flight testing proved the aircraft to exceed performance estimates in several aspects. During May 1951, Bråvalla Wing (F 13) received the first production aircraft. Five principal variants of the Tunnan were produced; the first model to enter service being the J 29A fighter,

7200-400: The smaller atoms become trapped in the interstitial sites between the atoms of the crystal matrix. This is referred to as an interstitial alloy . Steel is an example of an interstitial alloy, because the very small carbon atoms fit into interstices of the iron matrix. Stainless steel is an example of a combination of interstitial and substitutional alloys, because the carbon atoms fit into

7296-456: The term alloy steel usually only refers to steels that contain other elements— like vanadium , molybdenum , or cobalt —in amounts sufficient to alter the properties of the base steel. Since ancient times, when steel was used primarily for tools and weapons, the methods of producing and working the metal were often closely guarded secrets. Even long after the Age of Enlightenment , the steel industry

7392-512: The type. In service, the J 29 proved to be relatively fast and agile. The Swedish Air Force operated the type in both fighter and fighter-bomber roles into the 1970s. Sweden had fallen behind the rapid technical progress being made elsewhere, and Saab needed to catch up in terms of aerodynamics and jet propulsion. Accordingly, project "JxR" was initiated in late 1945 and requirements were drawn up in October 1945. A pair of proposals were presented by

7488-478: The use of a straight-through airflow to maximize thrust. Automatically locking leading edge slots , interconnected with the flaps , were also deemed necessary for lateral stability during take-off and landing. To further verify the swept wing, a Saab Safir was modified with a full-scale wing as the Saab 201 . The finalized design, incorporating the new information was drawn up in January 1946. The original powerplant

7584-824: Was another common alloy. However, in ancient times, it could only be created as an accidental byproduct from the heating of iron ore in fires ( smelting ) during the manufacture of iron. Other ancient alloys include pewter , brass and pig iron . In the modern age, steel can be created in many forms. Carbon steel can be made by varying only the carbon content, producing soft alloys like mild steel or hard alloys like spring steel . Alloy steels can be made by adding other elements, such as chromium , molybdenum , vanadium or nickel , resulting in alloys such as high-speed steel or tool steel . Small amounts of manganese are usually alloyed with most modern steels because of its ability to remove unwanted impurities, like phosphorus , sulfur and oxygen , which can have detrimental effects on

7680-422: Was applied as a paste and then heated until the mercury vaporized, leaving the gold, silver, or tin behind. Mercury was often used in mining, to extract precious metals like gold and silver from their ores. Many ancient civilizations alloyed metals for purely aesthetic purposes. In ancient Egypt and Mycenae , gold was often alloyed with copper to produce red-gold, or iron to produce a bright burgundy-gold. Gold

7776-455: Was bolted to the fuselage at three points and a special trolley was used to remove the engine for maintenance. The final version had an afterburner , the first successful one used with a British jet engine. Improvements were made to the wing to incorporate a dog-tooth leading edge, raising the critical Mach number . From 1963 onwards, all frontline J 29Fs were equipped with AIM-9 Sidewinder infrared -seeking air-to-air missiles . The J 29

7872-535: Was commissioned by the King of Syracuse to find a way to check the purity of the gold in a crown, leading to the famous bath-house shouting of "Eureka!" upon the discovery of Archimedes' principle . The term pewter covers a variety of alloys consisting primarily of tin. As a pure metal, tin is much too soft to use for most practical purposes. However, during the Bronze Age , tin was a rare metal in many parts of Europe and

7968-407: Was eventually adopted officially. Four prototypes were built for the test program. The first two lacked armament, carrying heavy test equipment in their place instead. The third was armed with four 20 mm (0.79 in) cannons. Air brakes on the fuselage and on the wings behind the rear spar and both conventional and combined aileron / flap arrangements were tested. Flight tests revealed that

8064-432: Was fast and agile, and set the world speed record on a 500 km (310 mi) closed circuit in 1954 at 977 km/h (607.05 mph). Two S 29C (reconnaissance variant) additionally set an international speed record of 900.6 km/h (559.4 mph) over a 1,000 km (620 mi) closed-circuit course in 1955. The crash record in early service was poor, mainly due to the inexperience with swept-winged aircraft and

8160-496: Was flying a Vampire Mk I modified by replacement of the Goblin engine with a Ghost engine, and installation of extended wing tips. The Ghost originated when de Havilland started work on what was to become the Comet in 1943. Frank Halford 's first design, the H-1, was just entering production and he was able to meet the power requirements of the Comet by scaling up the H-1. The resulting H-2 used ten larger combustion chambers in place of

8256-436: Was followed by the J 29B and J 29E fighters, and finally the afterburner -equipped J 29F fighter, which was the final variant built. There was also a dedicated reconnaissance variant, the S 29C . Between 1950 and 1956, 661 Tunnans were completed, the largest production run for any Saab aircraft. The Saab 29 Tunnan was the first Swedish aircraft to be specifically designed to use jet propulsion. Sweden's first jet fighter,

8352-609: Was given a 25 degree sweep. Information on swept wings came through Switzerland and included drawings for the Messerschmitt P.1101 , P.1110 , P.1111 and P.1112 . SAAB's project manager, Frid Wänström , collected these documents in 1945 from Messerschmitt engineers who escaped to Switzerland at the end of the War. Among them were engineer and aerodynamicist Hermann Behrbohm , who joined Saab's J 29 team. These documents clearly indicated delta and swept-wing designs "reduc[e] drag dramatically as

8448-777: Was later selected by the Fleet Air Arm for their interceptor needs, and was widely used as the Sea Venom . Data from Aircraft engines of the World 1957. Related development Comparable engines Related lists Alloy An alloy is a mixture of chemical elements of which in most cases at least one is a metallic element, although it is also sometimes used for mixtures of elements; herein only metallic alloys are described. Most alloys are metallic and show good electrical conductivity , ductility , opacity , and luster , and may have properties that differ from those of

8544-416: Was not generally considered an alloy until the decades between 1930 and 1970 (primarily due to the work of scientists like William Chandler Roberts-Austen , Adolf Martens , and Edgar Bain ), so "alloy steel" became the popular term for ternary and quaternary steel-alloys. After Benjamin Huntsman developed his crucible steel in 1740, he began experimenting with the addition of elements like manganese (in

8640-450: Was often found alloyed with silver or other metals to produce various types of colored gold . These metals were also used to strengthen each other, for more practical purposes. Copper was often added to silver to make sterling silver , increasing its strength for use in dishes, silverware, and other practical items. Quite often, precious metals were alloyed with less valuable substances as a means to deceive buyers. Around 250 BC, Archimedes

8736-588: Was shaped by cold hammering into knives and arrowheads. They were often used as anvils. Meteoric iron was very rare and valuable, and difficult for ancient people to work . Iron is usually found as iron ore on Earth, except for one deposit of native iron in Greenland , which was used by the Inuit . Native copper, however, was found worldwide, along with silver, gold, and platinum , which were also used to make tools, jewelry, and other objects since Neolithic times. Copper

8832-476: Was the de Havilland Engine Company 's second design of a turbojet engine to enter production and the world's first gas turbine engine to enter airline service (with BOAC ). The Ghost powered the de Havilland Venom , de Havilland Comet and SAAB 29 Tunnan . It was a scaled-up development of the Goblin . On 23 March 1948, John Cunningham achieved a new world altitude record of 59,446 ft (18,119 m). He

8928-492: Was the hardest of these metals, and the most widely distributed. It became one of the most important metals to the ancients. Around 10,000 years ago in the highlands of Anatolia (Turkey), humans learned to smelt metals such as copper and tin from ore . Around 2500 BC, people began alloying the two metals to form bronze, which was much harder than its ingredients. Tin was rare, however, being found mostly in Great Britain. In

9024-477: Was to have been the de Havilland Goblin turbojet , however, in December 1945, the more powerful de Havilland Ghost became available. This was ideal as not only was the Ghost set up for a circular air intake, its diameter would fit within the planned fuselage. Following negotiations between de Havilland and Saab, the Ghost engine was selected to power the type. Despite early doubts for the supply of an equivalent to

9120-557: Was very competitive and manufacturers went through great lengths to keep their processes confidential, resisting any attempts to scientifically analyze the material for fear it would reveal their methods. For example, the people of Sheffield , a center of steel production in England, were known to routinely bar visitors and tourists from entering town to deter industrial espionage . Thus, almost no metallurgical information existed about steel until 1860. Because of this lack of understanding, steel

9216-556: Was widespread across Europe, from France to Norway and Britain (where most of the ancient tin was mined) to the Near East. The alloy was also used in China and the Far East, arriving in Japan around 800 AD, where it was used for making objects like ceremonial vessels, tea canisters, or chalices used in shinto shrines. The first known smelting of iron began in Anatolia , around 1800 BC. Called

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