1.
Pittsburgh
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Pittsburgh is a city in the Commonwealth of Pennsylvania in the United States, and is the county seat of Allegheny County. The city proper has a population of 304,391. The metropolitan population of 2,353,045 is the largest in both the Ohio Valley and Appalachia, the second-largest in Pennsylvania, and the 26th-largest in the U. S. The city features 30 skyscrapers, two inclines, a fortification and the Point State Park at the confluence of the rivers. Aside from steel, Pittsburgh has led in manufacturing of aluminum, glass, shipbuilding, petroleum, foods, sports, transportation, computing, autos, and electronics. For part of the 20th century, Pittsburgh was behind only New York and Chicago in corporate headquarters employment, Americas 1980s deindustrialization laid off area blue-collar workers and thousands of downtown white-collar workers when the longtime Pittsburgh-based world headquarters moved out. The area has served also as the federal agency headquarters for cyber defense, software engineering, robotics, energy research. The area is home to 68 colleges and universities, including research and development leaders Carnegie Mellon University, the region is a hub for Leadership in Energy and Environmental Design, sustainable energy, and energy extraction. Pittsburgh was named in 1758 by General John Forbes, in honor of British statesman William Pitt, 1st Earl of Chatham. The current pronunciation, which is unusual in English speaking countries, is almost certainly a result of a printing error in some copies of the City Charter of March 18,1816. The error was repeated commonly enough throughout the rest of the 19th century that the pronunciation was lost. After a public campaign the original spelling was restored by the United States Board on Geographic Names in 1911. The area of the Ohio headwaters was long inhabited by the Shawnee, the first known European to enter the region was the French explorer/trader Robert de La Salle from Quebec during his 1669 expedition down the Ohio River. European pioneers, primarily Dutch, followed in the early 18th century, Michael Bezallion was the first to describe the forks of the Ohio in a 1717 manuscript, and later that year European fur traders established area posts and settlements. In 1749, French soldiers from Quebec launched an expedition to the forks to unite Canada with French Louisiana via the rivers, during 1753–54, the British hastily built Fort Prince George before a larger French force drove them off. The French built Fort Duquesne based on LaSalles 1669 claims, the French and Indian War, the North American front of the Seven Years War, began with the future Pittsburgh as its center. British General Edward Braddock was dispatched with Major George Washington as his aide to take Fort Duquesne, the British and colonial force were defeated at Braddocks Field. General John Forbes finally took the forks in 1758, Forbes began construction on Fort Pitt, named after William Pitt the Elder while the settlement was named Pittsborough
2.
Landing Ship, Tank
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This provided amphibious assaults to almost any beach. The bow of the LST had a door that would open with a ramp for unloading the vehicles. The LST had a flat keel that allowed the ship to be beached. The twin propellers and rudders had protection from grounding, the LSTs served across the globe during World War II including, Pacific War and European theatre. The first tank landing ships were built to British requirements by converting existing ships, then the British, over 1,000 LSTs were laid down in the United States during World War II for use by the Allies. Eighty more were built in the United Kingdom and Canada, as an interim measure, three 4, 000- to 4, 800-GRT tankers, built to pass over the restrictive bars of Lake Maracaibo, Venezuela, were selected for conversion because of their shallow draft. Bow doors and ramps were added to ships, which became the first tank landing ships, LST, HMS Misoa, Tasajera. They later proved their worth during the invasion of Algeria in 1942, the first purpose-built LST design was HMS Boxer. It was a design from ideas penned by Prime Minister Winston Churchill. In order that it could carry 13 Churchill infantry tanks,27 other vehicles and nearly 200 men at a speed of 18 knots, as a result, each of the three ordered in March 1941 had a very long ramp stowed behind the bow doors. The three ships were converted to Fighter Direction Ships for the invasion of Normandy, the U. S. were to build seven LST but in light of the problems with the design and progress with the LCT Mark II the plans were canceled. Construction of the LCTs took until 1943 and the first US LCT was launched before them, at their first meeting at the Atlantic conference in Argentia, Newfoundland, in August 1941, President Franklin D. Roosevelt and Prime Minister Winston Churchill confirmed the Admiraltys views. During this meeting, it was decided that the Bureau of Ships would design these vessels, as with the standing agreement, these ships would be built by the US so British shipyards could concentrate on building vessels for the Royal Navy. The specifications called for vessels capable of crossing the Atlantic, calling a vessel 300 ft long a craft was considered a misnomer and the type was re-christened Landing Ship, Tank, or LST. The LST design incorporated elements of the first British LCTs from their designer, Sir Rowland Baker, one of the elements provided for sufficient buoyancy in the ships sidewalls so that they would float the ship even when the tank deck was flooded. The LST gave up the speed of HMS Boxer, at only 10 knots, within a few days, John C. Niedermair of the Bureau of Ships sketched out an awkward looking ship that proved to be the design for the more than 1,000 LST that were built during World War II. An anchor and mechanical winch system also aided in the ability to pull itself off the beach
3.
Metre
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The metre or meter, is the base unit of length in the International System of Units. The metre is defined as the length of the path travelled by light in a vacuum in 1/299792458 seconds, the metre was originally defined in 1793 as one ten-millionth of the distance from the equator to the North Pole. In 1799, it was redefined in terms of a metre bar. In 1960, the metre was redefined in terms of a number of wavelengths of a certain emission line of krypton-86. In 1983, the current definition was adopted, the imperial inch is defined as 0.0254 metres. One metre is about 3 3⁄8 inches longer than a yard, Metre is the standard spelling of the metric unit for length in nearly all English-speaking nations except the United States and the Philippines, which use meter. Measuring devices are spelled -meter in all variants of English, the suffix -meter has the same Greek origin as the unit of length. This range of uses is found in Latin, French, English. Thus calls for measurement and moderation. In 1668 the English cleric and philosopher John Wilkins proposed in an essay a decimal-based unit of length, as a result of the French Revolution, the French Academy of Sciences charged a commission with determining a single scale for all measures. In 1668, Wilkins proposed using Christopher Wrens suggestion of defining the metre using a pendulum with a length which produced a half-period of one second, christiaan Huygens had observed that length to be 38 Rijnland inches or 39.26 English inches. This is the equivalent of what is now known to be 997 mm, no official action was taken regarding this suggestion. In the 18th century, there were two approaches to the definition of the unit of length. One favoured Wilkins approach, to define the metre in terms of the length of a pendulum which produced a half-period of one second. The other approach was to define the metre as one ten-millionth of the length of a quadrant along the Earths meridian, that is, the distance from the Equator to the North Pole. This means that the quadrant would have defined as exactly 10000000 metres at that time. To establish a universally accepted foundation for the definition of the metre, more measurements of this meridian were needed. This portion of the meridian, assumed to be the length as the Paris meridian, was to serve as the basis for the length of the half meridian connecting the North Pole with the Equator
4.
Electro-Motive Diesel
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Electro-Motive Diesel is an American manufacturer of diesel-electric locomotives, locomotive products and diesel engines for the rail industry. The company is owned by Caterpillar through its subsidiary Progress Rail Services Corporation, in 1930, General Motors purchased Electro-Motive Company and the Winton Engine Co. combining the two to form its Electro-Motive Division in 1941. In 2005, GM sold EMD to Greenbriar Equity Group and Berkshire Partners, in 2010, Progress Rail Services completed the purchase of Electro-Motive Diesel from Greenbriar, Berkshire, and others. EMDs headquarters, engineering facilities and parts manufacturing operations are based in McCook, Illinois, while its final assembly line is located in Muncie. EMD also operates a traction motor maintenance, rebuild and overhaul facility in San Luis Potosí, as of 2008, EMD employed approximately 3,260 people, and in 2010 it held approximately 30 percent of the market for diesel-electric locomotives in North America. Harold L. Hamilton and Paul Turner founded the Electro-Motive Engineering Corporation in Cleveland, Ohio, in 1922, the company developed and marketed self-propelled railcars using General Electrics newly developed internal combustion-electric propulsion and control systems. Hamilton started his career as a fireman, then locomotive engineer, on the Southern Pacific Railroad. Financing himself, he quit his sales position and set up shop in a hotel with his partner. In 1923 EMC sold two gasoline-powered rail motor cars, one to the Chicago Great Western and the other to the Northern Pacific, EMC subcontracted the body construction to St. Louis Car Company, electrical components to General Electric, and the prime mover to Winton Engine Company. The motorcars were delivered in 1924 and worked well, fortunate for the fledgling company, in 1925, EMC entered full-scale production, selling 27 railcars. In 1930 General Motors was seeking to improve their Diesel technology and they purchased the Winton Engine Company who, in addition to their Diesel products, sold non-Diesel engines for EMC-developed rail motorcars. The combined resources of GM and their new Winton subsidiary were focused on developing Diesel engines with improved power-to-weight ratios, GM saw EMCs role in marketing and applications development as fitting their objectives and purchased the company shortly after the Winton acquisition, renaming it Electro-Motive Corporation. In 1933 EMC designed the power setups for the Zephyr and M-10000 streamliners, the Zephyr used the first major product of the new GM-Winton venture, the 600 hp Winton 201A 2-stroke Diesel engine. Encouraged by the success of the new streamliners, EMC invested in a new locomotive factory. The new headquarters on 55th Street in McCook, Illinois, west of Chicago, in 1938 EMC started production of locomotives using GMs new 567 engine, which upgraded the horsepower to 2000 per locomotive unit and increased reliability. The 567, named for its displacement-per-cylinder of 567.45 in³, was a two-cycle Roots-blown, Uniflow-scavenged, Unit-injected engine with overhead camshafts and it was built as a V-6, V-8, V-12 and V-16. Charles F. Kettering and the General Motors Research Corporation were in charge of its development and their nearest competitor was the American Locomotive Company, who started production of less-developed Diesel locomotives to compete with the E-units in 1939. Baldwins response to the challenge of the E-units was to develop a steam locomotive design that pushed beyond the limits of practicality, passenger trains made little money for the railroads, but replacement of steam engines with reliable Diesel units could provide railroads with a crucial difference for profitability
5.
EMD 567
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The EMD567 is a line of large medium-speed diesel engines built by General Motors Electro-Motive Division. This engine, which succeeded Wintons 201A, was used in EMDs locomotives from 1938 until its replacement in 1966 by the EMD645 and it has a bore of 8 1⁄2 in, a stroke of 10 in and a displacement of 567 cu in per cylinder. Like the 201A, the EMD645 and the EMD710 and it is a V engine with an angle of 45° between cylinder banks. The 710,645, and 567 are the only two-stroke engines commonly used today in locomotives, eugene W. Kettering, son of Charles F. Kettering, joined Winton Engine in 1930. He moved to Detroit in 1936, and was a figure in the development of the 567. He moved to EMD in 1938, became Chief Engineer at EMD in 1948, then Division Director in 1956, although this power increase is not recommended, horsepower-for-horsepower updates are quite successful and common. Because of their age,567 engines are exempt from emissions rules. EMD manufactures a series of 645 power assemblies which are particularly useful in updating these exempt 567 engines. EMDs chief competitor, GE, now makes EMD-compatible replacement parts, all 567 engines are two-stroke 45 degree V-engines. The engine is a design with four poppet-type exhaust valves in the cylinder head. For maintenance, an assembly, consisting of a cylinder head, cylinder liner, piston, piston carrier. The block is made flat, formed and rolled structural steel members. Blocks may, therefore, be repaired, if required. Each bank of cylinders has a camshaft which operates the exhaust valves. The 567 is laid out with engine accessories at the forward end, the blowers and camshafts are at the rear end of the engine, with the blowers mounted above the power take off. All engines have mechanically-controlled unit injectors, see EMD645 for general specifications common to all 567-645-710 engines. All 567 engines utilize forced induction, with either a Roots blower or a turbocharger, at higher engine speeds, increased exhaust gas temperature is sufficient to drive the turbine and the clutch disengages, turning the turbo-compressor system into a true turbocharger. The turbo-compressor can revert to compressor mode momentarily during demands for large increases in output power
6.
Diesel engine
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Diesel engines work by compressing only the air. This increases the air temperature inside the cylinder to such a degree that it ignites atomised diesel fuel that is injected into the combustion chamber. This contrasts with spark-ignition engines such as an engine or gas engine. In diesel engines, glow plugs may be used to aid starting in cold weather, or when the engine uses a lower compression-ratio, the original diesel engine operates on the constant pressure cycle of gradual combustion and produces no audible knock. Low-speed diesel engines can have an efficiency that exceeds 50%. Diesel engines may be designed as either two-stroke or four-stroke cycles and they were originally used as a more efficient replacement for stationary steam engines. Since the 1910s they have used in submarines and ships. Use in locomotives, trucks, heavy equipment and electricity generation plants followed later, in the 1930s, they slowly began to be used in a few automobiles. Since the 1970s, the use of engines in larger on-road and off-road vehicles in the US increased. According to the British Society of Motor Manufacturing and Traders, the EU average for diesel cars accounts for 50% of the total sold, including 70% in France and 38% in the UK. The worlds largest diesel engine is currently a Wärtsilä-Sulzer RTA96-C Common Rail marine diesel, the definition of a Diesel engine to many has become an engine that uses compression ignition. To some it may be an engine that uses heavy fuel oil, to others an engine that does not use spark ignition. However the original cycle proposed by Rudolf Diesel in 1892 was a constant temperature cycle which would require higher compression than what is needed for compression ignition. Diesels idea was to compress the air so tightly that the temperature of the air would exceed that of combustion, to make this more clear, let it be assumed that the subsequent combustion shall take place at a temperature of 700°. Then in that case the pressure must be sixty-four atmospheres, or for 800° centigrade the pressure must be ninety atmospheres. In later years Diesel realized his original cycle would not work, Diesel describes the cycle in his 1895 patent application. Notice that there is no longer a mention of compression temperatures exceeding the temperature of combustion, now all that is mentioned is the compression must be high enough for ignition. In 1806 Claude and Nicéphore Niépce developed the first known internal combustion engine, the Pyréolophore fuel system used a blast of air provided by a bellows to atomize Lycopodium
7.
Gear train
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A transmission is a machine in a power transmission system, which provides controlled application of the power. Often the term refers simply to the gearbox that uses gears and gear trains to provide speed. In British English, the term refers to the whole drivetrain, including clutch, gearbox, prop shaft, differential. In American English, however, the term more specifically to the gearbox alone. The most common use is in vehicles, where the transmission adapts the output of the internal combustion engine to the drive wheels. Such engines need to operate at a high rotational speed, which is inappropriate for starting, stopping. The transmission reduces the engine speed to the slower wheel speed. Transmissions are also used on bicycles, fixed machines. Often, a transmission has multiple gear ratios with the ability to switch between them as speed varies and this switching may be done manually or automatically. Directional control may also be provided, single-ratio transmissions also exist, which simply change the speed and torque of motor output. The output of the transmission is transmitted via the driveshaft to one or more differentials, while a differential may also provide gear reduction, its primary purpose is to permit the wheels at either end of an axle to rotate at different speeds as it changes the direction of rotation. Conventional gear/belt transmissions are not the mechanism for speed/torque adaptation. Alternative mechanisms include torque converters and power transformation, automatic transmissions use a valve body to shift gears using fluid pressures in conjunction with an ecm. Early transmissions included the right-angle drives and other gearing in windmills, horse-powered devices, and steam engines, in support of pumping, milling, most modern gearboxes are used to increase torque while reducing the speed of a prime mover output shaft. This means that the shaft of a gearbox rotates at a slower rate than the input shaft. A gearbox can be set up to do the opposite and provide an increase in speed with a reduction of torque. Some of the simplest gearboxes merely change the rotational direction of power transmission. Many typical automobile transmissions include the ability to select one of several gear ratios, in this case, most of the gear ratios are used to slow down the output speed of the engine and increase torque
8.
Propeller
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A propeller is a type of fan that transmits power by converting rotational motion into thrust. A pressure difference is produced between the forward and rear surfaces of the blade, and a fluid is accelerated behind the blade. Their disadvantages are higher mechanical complexity and higher cost, the principle employed in using a screw propeller is used in sculling. It is part of the skill of propelling a Venetian gondola but was used in a less refined way in parts of Europe. For example, propelling a canoe with a paddle using a pitch stroke or side slipping a canoe with a scull involves a similar technique. In China, sculling, called lu, was used by the 3rd century AD. In sculling, a blade is moved through an arc. The innovation introduced with the propeller was the extension of that arc through more than 360° by attaching the blade to a rotating shaft. Propellers can have a blade, but in practice there are nearly always more than one so as to balance the forces involved. The origin of the screw propeller starts with Archimedes, who used a screw to lift water for irrigation and bailing boats and it was probably an application of spiral movement in space to a hollow segmented water-wheel used for irrigation by Egyptians for centuries. Leonardo da Vinci adopted the principle to drive his theoretical helicopter, in 1784, J. P. Paucton proposed a gyrocopter-like aircraft using similar screws for both lift and propulsion. At about the time, James Watt proposed using screws to propel boats. This was not his own invention, though, Toogood and Hays had patented it a century earlier, by 1827, Czech-Austrian inventor Josef Ressel had invented a screw propeller which had multiple blades fastened around a conical base. He had tested his propeller in February 1826 on a ship that was manually driven. He was successful in using his bronze screw propeller on an adapted steamboat and his ship Civetta with 48 gross register tons, reached a speed of about six knots. This was the first ship successfully driven by an Archimedes screw-type propeller, after a new steam engine had an accident his experiments were banned by the Austro-Hungarian police as dangerous. Josef Ressel was at the time a forestry inspector for the Austrian Empire, but before this he received an Austro-Hungarian patent for his propeller. This new method of propulsion was an improvement over the paddlewheel as it was not so affected by either ship motions or changes in draft as the burned coal
9.
Miles per hour
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Miles per hour is an imperial and United States customary unit of speed expressing the number of statute miles covered in one hour. Miles per hour is the also used in the Canadian rail system. In some countries mph may be used to express the speed of delivery of a ball in sporting events such as cricket, tennis, road traffic speeds in other countries are indicated in kilometres per hour, while occasionally both systems are used. For example, in Ireland, a considered a speeding case by examining speeds in both kilometres per hour and miles per hour. The judge was quoted as saying the speed seemed very excessive at 180 km/h but did not look as bad at 112 mph, nautical and aeronautical applications, however, favour the knot as a common unit of speed. 1 Mph =0.000277778 Mps Example, Apollo 11 attained speeds of 25,000 Mph, if Apollo 11 were to travel at 25,000 Mph from New York to Los Angeles it would reach Los Angeles in under 6 minutes
10.
LCVP (United States)
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The landing craft, vehicle, personnel or Higgins boat was a landing craft used extensively in amphibious landings in World War II. The craft was designed by Andrew Higgins based on boats made for operating in swamps, more than 20,000 were built, by Higgins Industries and licensees. Typically constructed from plywood, this shallow-draft, barge-like boat could ferry a platoon-sized complement of 36 men to shore at 9 knots. Men generally entered the boat by climbing down a cargo net hung from the side of their troop transport, they exited by charging down the boats bow ramp. Satisfactory in most respects, the major drawback appeared to be that equipment had to be unloaded. However, it was put into production and service as the craft, personnel. The LCP had two gun positions at the bow. The LCP, commonly called the U-boat or the Higgins boat, was supplied to the British, to whom it was known as the R-boat. Within one month, tests of the ramp-bow Eureka boat in Lake Pontchartrain showed conclusively that successful operation of such a boat was feasible and this boat became the Landing Craft, Personnel or LCP. The machine gun positions were still at the front of the boat, the design was still not ideal, because the ramp was a bottleneck for the troops, as was the case with the British Landing Craft Assault of the year before. The next step was to fit a full-width ramp, now troops could leave en masse and a small vehicle such as a Jeep could be carried, this new version became the LCVP, or simply, the Higgins boat. The machine gun positions were moved to the rear of the boat, at just over 36 ft long and just under 11 ft wide, the LCVP was not a large craft. Powered by a 225-horsepower Diesel engine at 12 knots, it would sway in choppy seas, since its sides and rear were made of plywood, it offered limited protection from enemy fire. The Higgins boat could hold either a 36-man platoon, a jeep and its shallow draft enabled it to run up onto the shoreline, and a semi-tunnel built into its hull protected the propeller from sand and other debris. The steel ramp at the front could be lowered quickly and it was possible for the Higgins boat to swiftly disembark men and supplies, reverse itself off the beach, and head back out to the supply ship for another load within three to four minutes. If Higgins had not designed and built those LCVPs, we never could have landed over an open beach, the whole strategy of the war would have been different. Only a few Higgins boats have survived, often with modifications for post-War use. A remarkably preserved Higgins boat, with the original Higgins motor, was discovered in a yard in Valdez, Alaska
11.
Kilogram
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The kilogram or kilogramme is the base unit of mass in the International System of Units and is defined as being equal to the mass of the International Prototype of the Kilogram. The avoirdupois pound, used in both the imperial and US customary systems, is defined as exactly 0.45359237 kg, making one kilogram approximately equal to 2.2046 avoirdupois pounds. Other traditional units of weight and mass around the world are also defined in terms of the kilogram, the gram, 1/1000 of a kilogram, was provisionally defined in 1795 as the mass of one cubic centimeter of water at the melting point of ice. The final kilogram, manufactured as a prototype in 1799 and from which the IPK was derived in 1875, had an equal to the mass of 1 dm3 of water at its maximum density. The kilogram is the only SI base unit with an SI prefix as part of its name and it is also the only SI unit that is still directly defined by an artifact rather than a fundamental physical property that can be reproduced in different laboratories. Three other base units and 17 derived units in the SI system are defined relative to the kilogram, only 8 other units do not require the kilogram in their definition, temperature, time and frequency, length, and angle. At its 2011 meeting, the CGPM agreed in principle that the kilogram should be redefined in terms of the Planck constant, the decision was originally deferred until 2014, in 2014 it was deferred again until the next meeting. There are currently several different proposals for the redefinition, these are described in the Proposed Future Definitions section below, the International Prototype Kilogram is rarely used or handled. In the decree of 1795, the term gramme thus replaced gravet, the French spelling was adopted in the United Kingdom when the word was used for the first time in English in 1797, with the spelling kilogram being adopted in the United States. In the United Kingdom both spellings are used, with kilogram having become by far the more common, UK law regulating the units to be used when trading by weight or measure does not prevent the use of either spelling. In the 19th century the French word kilo, a shortening of kilogramme, was imported into the English language where it has used to mean both kilogram and kilometer. In 1935 this was adopted by the IEC as the Giorgi system, now known as MKS system. In 1948 the CGPM commissioned the CIPM to make recommendations for a practical system of units of measurement. This led to the launch of SI in 1960 and the subsequent publication of the SI Brochure, the kilogram is a unit of mass, a property which corresponds to the common perception of how heavy an object is. Mass is a property, that is, it is related to the tendency of an object at rest to remain at rest, or if in motion to remain in motion at a constant velocity. Accordingly, for astronauts in microgravity, no effort is required to hold objects off the cabin floor, they are weightless. However, since objects in microgravity still retain their mass and inertia, the ratio of the force of gravity on the two objects, measured by the scale, is equal to the ratio of their masses. On April 7,1795, the gram was decreed in France to be the weight of a volume of pure water equal to the cube of the hundredth part of the metre
12.
Cargo
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Multi-modal container units, designed as reusable carriers to facilitate unit load handling of the goods contained, are also referred to as cargo, specially by shipping lines and logistics operators. Similarly, aircraft ULD boxes are also documented as cargo, with associated packing list of the contained within. When empty containers are shipped each unit is documented as a cargo and when goods are stored within, seaport terminals handle a wide range of maritime cargo. Automobiles are handled at many ports and are carried on specialized roll-on/roll-off ships. Break bulk cargo is typically stacked on pallets and lifted into. The volume of bulk cargo has declined dramatically worldwide as containerization has grown. One way to secure break bulk and freight in intermodal containers is by using Dunnage Bags, bulk cargo, such as salt, oil, tallow, and scrap metal, is usually defined as commodities that are neither on pallets nor in containers. Bulk cargoes are not handled as individual pieces, the way heavy-lift, alumina, grain, gypsum, logs, and wood chips, for instance, are bulk cargoes. Neo-bulk cargo comprises individual units that are counted as they are loaded and unloaded, in contrast to bulk cargo that is not counted, containers are the largest and fastest growing cargo category at most ports worldwide. Containerized cargo includes everything from auto parts, machinery and manufacturing components to shoes and toys to frozen meat, air cargo, commonly known as air freight, is collected by firms from shippers and delivered to customers. Aircraft were first used for carrying mail as cargo in 1911, eventually manufacturers started designing aircraft for other types of freight as well. There are many commercial aircraft suitable for carrying cargo such as the Boeing 747 and the bigger An‑124, such large aircraft employ quick-loading containers known as unit load devices, much like containerized cargo ships. The ULDs are located in the front section of the aircraft, most nations own and utilize large numbers of military cargo aircraft such as the C‑17 Globemaster III for logistical needs. Popular commercial aircraft transformed to an aircraft such as Saab 340A is designed for high revenue. Trains are capable of transporting a number of containers that come from shipping ports. Trains are also used for the transportation of water, cement, grain, steel, wood and they are used because they can carry a large amount and generally have a direct route to the destination. Under the right circumstances, freight transport by rail is more economic and energy efficient than by road, the main disadvantage of rail freight is its lack of flexibility. For this reason, rail has lost much of the business to road transport
United States
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United States Navy