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Coffman Starter
The Coffman engine starter (also known as a "shotgun starter") was a starting system used on many piston engines in aircraft and armored vehicles of the 1930s and 1940s. It used a cordite cartridge to move a piston, which cranked the engine. The Coffman system was one of the most common brands; another was the Breeze cartridge system, which was produced under Coffman patents. Most American military aircraft and tanks which used radial engines were equipped with this system. Some versions of the Rolls-Royce Merlin engine used in the UK, British Supermarine Spitfire used the Coffman system as a starter. The Hawker Typhoon and Hawker Tempest also used the Coffman system to start their Napier Sabre engines. Cartridge starters used on a number of jet engines, including such engines as the Rolls-Royce Avon, which were used in the English Electric Canberra and Hawker Hunter aircraft, used a high gas volume cartridge driving a turbine instead of a piston. Some Snowcat and similar vehicles ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Piston
A piston is a component of reciprocating engines, reciprocating pumps, gas compressors, hydraulic cylinders and pneumatic cylinders, among other similar mechanisms. It is the moving component that is contained by a cylinder and is made gas-tight by piston rings. In an engine, its purpose is to transfer force from expanding gas in the cylinder to the crankshaft via a piston rod and/or connecting rod. In a pump, the function is reversed and force is transferred from the crankshaft to the piston for the purpose of compressing or ejecting the fluid in the cylinder. In some engines, the piston also acts as a valve by covering and uncovering ports in the cylinder. __TOC__ Piston engines Internal combustion engines An internal combustion engine is acted upon by the pressure of the expanding combustion gases in the combustion chamber space at the top of the cylinder. This force then acts downwards through the connecting rod and onto the crankshaft. The connecting rod is att ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cordite
Cordite is a family of smokeless propellants developed and produced in the United Kingdom since 1889 to replace black powder as a military propellant. Like modern gunpowder, cordite is classified as a low explosive because of its slow burning rates and consequently low brisance. These produce a subsonic deflagration wave rather than the supersonic detonation wave produced by brisants, or high explosives. The hot gases produced by burning gunpowder or cordite generate sufficient pressure to propel a bullet or shell to its target, but not so quickly as to routinely destroy the barrel of the gun. Cordite was used initially in the .303 British, Mark I and II, standard rifle cartridge between 1891 and 1915; shortages of cordite in World War I led to the creation of the "Devil's Porridge" munitions factory (HM Factory, Gretna) on the English-Scottish border, which produced 800 tonnes of cordite per annum. The UK also imported some United States–developed smokeless powders for us ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hearst Magazines
Hearst Communications, Inc., often referred to simply as Hearst, is an American multinational mass media and business information conglomerate based in Hearst Tower in Midtown Manhattan, New York City. Hearst owns newspapers, magazines, television channels, and television stations, including the ''San Francisco Chronicle'', the ''Houston Chronicle'', ''Cosmopolitan'' and ''Esquire''. It owns 50% of the A&E Networks cable network group and 20% of the sports cable network group ESPN, both in partnership with The Walt Disney Company. The conglomerate also owns several business-information companies, including Fitch Ratings and First Databank. The company was founded by William Randolph Hearst as an owner of newspapers, and the Hearst family remains involved in its ownership and management. History The formative years In 1880, George Hearst, mining entrepreneur and U.S. senator, bought the '' San Francisco Daily Examiner.'' In 1887, he turned the ''Examiner'' over to his son, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Popular Mechanics
''Popular Mechanics'' (sometimes PM or PopMech) is a magazine of popular science and technology, featuring automotive, home, outdoor, electronics, science, do-it-yourself, and technology topics. Military topics, aviation and transportation of all types, space, tools and gadgets are commonly featured. It was founded in 1902 by Henry Haven Windsor, who was the editor and—as owner of the Popular Mechanics Company—the publisher. For decades, the tagline of the monthly magazine was "Written so you can understand it." In 1958, PM was purchased by the Hearst Corporation, now Hearst Communications. In 2013, the US edition changed from twelve to ten issues per year, and in 2014 the tagline was changed to "How your world works." The magazine added a podcast in recent years, including regular features ''Most Useful Podcast Ever'' and ''How Your World Works''. History ''Popular Mechanics'' was founded in Chicago by Henry Haven Windsor, with the first issue dated January 11, 1902. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flame Holder
A flame holder is a component of a jet engine designed to help maintain continual combustion. In a scramjet engine the residence time of the fuel is very low and complete penetration of the fuel into the flow will not occur. To avoid these conditions flame holders are used. All continuous-combustion jet engines require a flame holder. A flame holder creates a low-speed eddy in the engine to prevent the flame from being blown out. The design of the flame holder is an issue of balance between a stable eddy and drag. The simplest design, often used in amateur projects, is the can-type flame holder, which consists of a can covered in small holes. Much more effective is the H-gutter flame holder, which is shaped like a letter H with a curve facing and opposing the flow of air. Even more effective, however, is the V-gutter flame holder, which is shaped like a V with the point in the direction facing the flow of air. Some studies have suggested that adding a small amount of base bleed ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Air-start System
An air-start system is a power source used to provide the initial rotation to start large diesel and gas turbine engines. Diesel engines Direct starting Compared to a gasoline (petrol) engine, a diesel engine has a very high compression ratio, an essential design feature, as it is the heat of compression that ignites the fuel. An electric starter with sufficient power to "crank" a large diesel engine would itself be so large as to be impractical, thus the need for an alternative system. When starting the engine, compressed air is admitted to whichever cylinder has a piston just over top dead center, forcing it downward. As the engine starts to turn, the air-start valve on the next cylinder in line opens to continue the rotation. After several rotations, fuel is injected into the cylinders, the engine starts running and the air is cut off. To further complicate matters, a large engine is usually "blown over" first with zero fuel settings and the indicator cocks open, to prove t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Steel
Steel is an alloy made up of iron with added carbon to improve its strength and fracture resistance compared to other forms of iron. Many other elements may be present or added. Stainless steels that are corrosion- and oxidation-resistant typically need an additional 11% chromium. Because of its high tensile strength and low cost, steel is used in buildings, infrastructure, tools, ships, trains, cars, machines, electrical appliances, weapons, and rockets. Iron is the base metal of steel. Depending on the temperature, it can take two crystalline forms (allotropic forms): body-centred cubic and face-centred cubic. The interaction of the allotropes of iron with the alloying elements, primarily carbon, gives steel and cast iron their range of unique properties. In pure iron, the crystal structure has relatively little resistance to the iron atoms slipping past one another, and so pure iron is quite ductile, or soft and easily formed. In steel, small amounts of carbon, other ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Air Start System
An air-start system is a power source used to provide the initial rotation to start large diesel and gas turbine engines. Diesel engines Direct starting Compared to a gasoline (petrol) engine, a diesel engine has a very high compression ratio, an essential design feature, as it is the heat of compression that ignites the fuel. An electric starter with sufficient power to "crank" a large diesel engine would itself be so large as to be impractical, thus the need for an alternative system. When starting the engine, compressed air is admitted to whichever cylinder has a piston just over top dead center, forcing it downward. As the engine starts to turn, the air-start valve on the next cylinder in line opens to continue the rotation. After several rotations, fuel is injected into the cylinders, the engine starts running and the air is cut off. To further complicate matters, a large engine is usually "blown over" first with zero fuel settings and the indicator cocks open, to prove that ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Starter (engine)
A starter (also self-starter, cranking motor, or starter motor) is a device used to rotate (crank) an internal-combustion engine so as to initiate the engine's operation under its own power. Starters can be electric, pneumatic, or hydraulic. The starter can also be another internal-combustion engine in the case, for instance, of very large engines, or diesel engines in agricultural or excavation applications. Internal combustion engines are feedback systems, which, once started, rely on the inertia from each cycle to initiate the next cycle. In a four-stroke engine, the third stroke releases energy from the fuel, powering the fourth (exhaust) stroke and also the first two (intake, compression) strokes of the next cycle, as well as powering the engine's external load. To start the first cycle at the beginning of any particular session, the first two strokes must be powered in some other way than from the engine itself. The starter motor is used for this purpose and it is not re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Field-Marshall
Field-Marshall was a brand of farm tractor which was manufactured by Marshall, Sons & Co. of Gainsborough, Lincolnshire in the United Kingdom. Field-Marshalls were in production from 1945 to 1957. However, the first single-cylinder Marshall came into production in 1930. Earlier Marshall tractor line The first single-cylinder Marshall tractor to be introduced was the Marshall 15/30 in 1930. It had a bore with a stroke (= 8.237 litres) and the maximum speed was 550 r.p.m., or 9.1666 revolutions per second. In 1932 the 15/30 was upgraded to become the Marshall 18/30. This model featured the same bore and stroke dimensions but the maximum r.p.m. was increased and the tractor's transmission was heavily modified. The next single-cylinder Marshall to be introduced was the Marshall 12/20 in 1935. This tractor was of a completely new design, with a -inch bore and a stroke (= 4.17 litres). There were many smaller modifications such as a redesigned injection pump and cylinder head. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flight International
''Flight International'' is a monthly magazine focused on aerospace. Published in the United Kingdom and founded in 1909 as "A Journal devoted to the Interests, Practice, and Progress of Aerial Locomotion and Transport", it is the world's oldest continuously published aviation news magazine. ''Flight International'' is published by DVV Media Group. Competitors include Jane's Information Group and ''Aviation Week''. Former editors of, and contributors include H. F. King, Bill Gunston, John W. R. Taylor and David Learmount. History The founder and first editor of ''Flight'' was Stanley Spooner. He was also the creator and editor of ''The Automotor Journal'', originally titled ''The Automotor Journal and Horseless Vehicle''.Guide To British Industrial History: Biographies: ''Stan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Blank Cartridge
A blank is a firearm cartridge that, when fired, does not shoot a projectile like a bullet or pellet, but generates a muzzle flash and an explosive sound ( muzzle report) like a normal gunshot would. Firearms may need to be modified to allow a blank to cycle the action, and the shooter experiences less recoil with a blank than with a live round. Blanks are often used in prop guns for shooting simulations that have no need for ballistic results, but still demand light and sound effects, such as in historical reenactments, special effects for theatre, movie and television productions, combat training, for signaling (see starting pistol), and cowboy mounted shooting. Specialised blank cartridges are also used for their propellant force in fields as varied as construction, shooting sports, and fishing and general recreation. While blanks are less dangerous than live ammunition, they are dangerous and can still cause fatal injuries. Beside the explosive gases, any objects in the cartri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
