An aircraft engine is a component of the propulsion system for an aircraft that generates mechanical power. Aircraft engines are always either lightweight piston engines or gas turbines, except for small multicopter UAVs which are always electric aircraft. In commercial aviation, the major players in the manufacturing of turbofan engines are Pratt & Whitney, General Electric, Rolls-Royce, CFM International. A major entrant into the market launched in 2016 when Aeroengine Corporation of China was formed by organizing smaller companies engaged in designing and manufacturing aircraft engines into a new state owned behemoth of 96,000 employees. In general aviation, the dominant manufacturer of turboprop engines has been Whitney. General Electric announced in 2015 entrance into the market. 1848: John Stringfellow made a steam engine for a 10-foot wingspan model aircraft which achieved the first powered flight, albeit with negligible payload. 1903: Charlie Taylor built an inline aeroengine for the Wright Flyer.
1903: Manly-Balzer engine sets standards for radial engines. 1906: Léon Levavasseur produces a successful water-cooled V8 engine for aircraft use. 1908: René Lorin patents a design for the ramjet engine. 1908: Louis Seguin designed the Gnome Omega, the world's first rotary engine to be produced in quantity. In 1909 a Gnome powered Farman III aircraft won the prize for the greatest non-stop distance flown at the Reims Grande Semaine d'Aviation setting a world record for endurance of 180 kilometres. 1910: Coandă-1910, an unsuccessful ducted fan aircraft exhibited at Paris Aero Salon, powered by a piston engine. The aircraft never flew, but a patent was filed for routing exhaust gases into the duct to augment thrust. 1914: Auguste Rateau suggests using exhaust-powered compressor – a turbocharger – to improve high-altitude performance. VI heavy bomber becomes the earliest known supercharger-equipped aircraft to fly, with a Mercedes D. II straight-six engine in the central fuselage driving a Brown-Boveri mechanical supercharger for the R.30/16's four Mercedes D.
IVa engines. 1918: Sanford Alexander Moss picks up Rateau's idea and creates the first successful turbocharger 1926: Armstrong Siddeley Jaguar IV, the first series-produced supercharged engine for aircraft use. 1930: Frank Whittle submitted his first patent for a turbojet engine. June 1939: Heinkel He 176 is the first successful aircraft to fly powered by a liquid-fueled rocket engine. August 1939: Heinkel HeS 3 turbojet propels the pioneering German Heinkel He 178 aircraft. 1940: Jendrassik Cs-1, the world's first run of a turboprop engine. It is not put into service. 1943 Daimler-Benz DB 670, first turbofan runs 1944: Messerschmitt Me 163B Komet, the world's first rocket-propelled combat aircraft deployed. 1945: First turboprop-powered aircraft flies, a modified Gloster Meteor with two Rolls-Royce Trent engines. 1947: Bell X-1 rocket-propelled aircraft exceeds the speed of sound. 1948: 100 shp 782, the first turboshaft engine to be applied to aircraft use. 1949: Leduc 010, the world's first ramjet-powered aircraft flight.
1950: Rolls-Royce Conway, the world's first production turbofan, enters service. 1968: General Electric TF39 high bypass turbofan enters service delivering greater thrust and much better efficiency. 2002: HyShot scramjet flew in dive. 2004: NASA X-43, the first scramjet to maintain altitude. In this entry, for clarity, the term "inline engine" refers only to engines with a single row of cylinders, as used in automotive language, but in aviation terms, the phrase "inline engine" covers V-type and opposed engines, is not limited to engines with a single row of cylinders; this is to differentiate them from radial engines. A straight engine has an number of cylinders, but there are instances of three- and five-cylinder engines; the greatest advantage of an inline engine is that it allows the aircraft to be designed with a low frontal area to minimize drag. If the engine crankshaft is located above the cylinders, it is called an inverted inline engine: this allows the propeller to be mounted high up to increase ground clearance, enabling shorter landing gear.
The disadvantages of an inline engine include a poor power-to-weight ratio, because the crankcase and crankshaft are long and thus heavy. An in-line engine may be either air-cooled or liquid-cooled, but liquid-cooling is more common because it is difficult to get enough air-flow to cool the rear cylinders directly. Inline engines were common in early aircraft. However, the inherent disadvantages of the design soon became apparent, the inline design was abandoned, becoming a rarity in modern aviation. For other configurations of aviation inline engine, such as U-engines, H-engines, etc.. See Inline engine. Cylinders in this engine are arranged in two in-line banks tilted 60–90 degrees apart from each other and driving a common crankshaft; the vast majority of V engines are water-cooled. The V design provides a higher power-to-weight ratio than an inline engine, while still providing a small frontal area; the most famous example of this design is the legendary Rolls-Royce Merlin engine, a 27-litre 60° V12 engine used in, among others, the Spitfires that played a major role in the Battle of Britain.
A horizontally opposed engine called a flat or boxer engine, ha
Douglas C-47 Skytrain
The Douglas C-47 Skytrain or Dakota is a military transport aircraft developed from the civilian Douglas DC-3 airliner. It was used extensively by the Allies during World War II and remains in front line service with various military operators; the C-47 differed from the civilian DC-3 in numerous modifications, including being fitted with a cargo door, hoist attachment, strengthened floor, along with a shortened tail cone for glider-towing shackles, an astrodome in the cabin roof. During World War II, the armed forces of many countries used the C-47 and modified DC-3s for the transport of troops and wounded; the U. S. Naval designation was R4D. More than 10,000 aircraft were produced in Long Beach and Santa Monica and Oklahoma City, Oklahoma. Between March 1943 and August 1945 the Oklahoma City plant produced 5,354 C-47s; the specialized C-53 Skytrooper troop transport started production in October 1941 at Douglas Aircraft's Santa Monica, California plant. It lacked the cargo door, hoist attachment, reinforced floor of the C-47.
Only a total of 380 aircraft were produced in all. The C-47 was vital to the success of many Allied campaigns, in particular those at Guadalcanal and in the jungles of New Guinea and Burma, where the C-47 made it possible for Allied troops to counter the mobility of the light-travelling Japanese Army. Additionally, C-47s were used to airlift supplies to the embattled American forces during the Battle of Bastogne, its most influential role in military aviation, was flying "The Hump" from India into China. The expertise gained flying "The Hump" was be used in the Berlin Airlift, in which the C-47 played a major role, until the aircraft were replaced by Douglas C-54 Skymasters. In Europe, the C-47 and a specialized paratroop variant, the C-53 Skytrooper, were used in vast numbers in the stages of the war to tow gliders and drop paratroops. During the invasion of Sicily in July 1943, C-47s dropped 4,381 Allied paratroops. More than 50,000 paratroops were dropped by C-47s during the first few days of the invasion of Normandy, France, in June 1944.
In the Pacific War, with careful use of the island landing strips of the Pacific Ocean, C-47s were used for ferrying soldiers serving in the Pacific theater back to the United States. About 2,000 C-47s in British and Commonwealth service took the name "Dakota" inspired by the acronym "DACoTA" for Douglas Aircraft Company Transport Aircraft; the C-47 earned the informal nickname "gooney bird" in the European theatre of operations. Other sources attribute this name to the first aircraft, a USMC R2D—the military version of the DC-2—being the first aircraft to land on Midway Island home to the long-winged albatross known as the gooney bird, native to Midway; the United States Air Force's Strategic Air Command had Skytrains in service from 1946 through 1967. The US Air Force's 6th Special Operations Squadron was flying the C-47 until 2008. With all of the aircraft and pilots having been part of the Indian Air Force prior to independence, both the Indian Air Force and Pakistan Air Force used C-47s to transport supplies to their soldiers fighting in the Indo-Pakistan War of 1947.
After World War II, thousands of surplus C-47s were converted to civil airline use, some remaining in operation in 2012, as well as being used as private aircraft. Several C-47 variations were used in the Vietnam War by the United States Air Force, including three advanced electronic warfare variations, which sometimes were called "electric gooneys" designated EC-47N, EC-47P, or EC-47Q depending on the engine used. Air International, Miami International Airport was a USAF military depot used to convert the commercial DC-3s/C-47s into military use, they came in as commercial aircraft purchased from third world airlines and were stripped and reconditioned. Long range fuel tanks were installed with upgraded avionics and gun mounts, they left as first rate military aircraft headed for combat in Vietnam in a variety of missions. EC-47s were operated by the Vietnamese and Cambodian Air Forces. A gunship variation, using three 7.62 mm miniguns, designated AC-47 "Spooky" nicknamed "Puff the magic dragon" was deployed.
Large numbers of DC-3s and surplus C-47s were in commercial use in the United States in the 1940s. In response to proposed changes to the Civil Air Regulations airworthiness requirements that would limit the continuing use of these aircraft, Douglas offered a late 1940s DC-3 conversion to improve takeoff and single-engine performance; this new model, the DC-3S or "Super DC-3", was 39 in longer. It allowed 30 passengers to be carried, with increased speed to compete with newer airliners; the rearward shift in the center of gravity led to larger tail surfaces and new outer, swept-back wings. More powerful engines were installed along with shorter, jet ejection-type exhaust stacks; these were either 1,475 hp Wright R-1820 Cyclones or 1,450 hp Pratt & Whitney R-2000 Twin Wasps in larger engine nacelles. Minor changes included wheel well doors, a retractable tailwheel, flush rivets, low drag antenna; these all contributed to an increased top speed of 250 mph. With greater than 75% of the original DC-3/C-47 configuration changed, the modified design was a new aircraft.
The first DC-3S made its maiden flight on 23 June 1949. The changes met the new FAR 4B airworthiness requirements, with improved performance. However, little interest was expressed by commercial operators in the DC-3S, it was too expensive for the smaller operators which were its main target: only three were sold to
Central business district
A central business district is the commercial and business center of a city. In larger cities, it is synonymous with the city's "financial district". Geographically, it coincides with the "city centre" or "downtown", but the two concepts are separate: many cities have a central business district located away from its commercial or cultural city centre or downtown; the CBD is also the "city centre" or "downtown", but this is often not the case. Midtown Manhattan is the largest central business district in the world. For example, London's "city centre" is regarded as encompassing the historic City of London and the mediaeval City of Westminster, whereas the City of London and the transformed Docklands area are regarded as its two CBDs. Mexico City has a historic city centre, the colonial-era Centro Histórico, along with two CBDs: the mid-late 20th century Paseo de la Reforma - Polanco, the new Santa Fe; the shape and type of a CBD always reflect the city's history. Cities with strong preservation laws and maximum building height restrictions to retain the character of the historic and cultural core will have a CBD quite a distance from the centre of the city.
This is quite common for European cities such as Vienna. In cities in the New World that grew after the invention of mechanised modes such as road or rail transport, a single central area or downtown will contain most of the region's tallest buildings and act both as the CBD and the commercial and cultural city center. Increasing urbanisation in the 21st century have developed megacities in Asia, that will have multiple CBDs scattered across the urban area, it has been said. No two CBDs look alike in terms of their spatial shape, however certain geometric patterns in these areas are recurring throughout many cities due to the nature of centralised commercial and industrial activities. In Australia the acronym CBD is used commonly to refer to major city "centres", it is used in particular to refer to the skyscraper districts in state capital cities such as Melbourne, Perth and Sydney. Melbourne is Australia's largest CBD with Sydney second and Brisbane third when judged by area size; the iTowers of Masa Square CBD were built for doing business tasks only.
It is located within Gaborone. In China terms "city centre" are used but a different commercial district outside of the historic core called a "CBD" or "Financial District" may exist. Large Chinese cities have multiple CBDs spread throughout the urban area. Cities traditionally being major cultural centres with many historic structures in the core such as Beijing, Suzhou or Xi'an will have the greenfield CBDs built adjacent to the urban core, similar to European cities. While other cities such as Guangzhou, Shanghai and Wuhan the city centre will house a number of CBDs in addition to greenfield CBDs built in the periphery. In France, the term « quartier d’affaires » may be used to describe the central business district; the main ones business districts in the country are as following: La Défense in Paris, which with 3,300,000 square metres of office space is Europe's leading business district in terms of area. La Part-Dieu in Lyon, is the 2nd largest business district in France and has nearly 1,600,000 square metres.
Euralille in Lille, is the 3rd business district of France with 1,120,000 square metres of offices. Euroméditerranée in Marseille, is the 4th business district in France with 650,000 square metres of offices. In Germany, the terms Innenstadt and Stadtzentrum may be used to describe the central business district. Both terms can be translated to mean "inner city" and "city centre"; some of the larger cities have more than one central business district, like Berlin, which has three. Due to Berlin's history of division during the Cold War, the city contains central business districts both in West and East Berlin, as well as a newly-built business centre near Potsdamer Platz; the city's historic centre — the location of the Reichstag building, as well as the Brandenburg gate and most federal ministries — was abandoned when the Berlin Wall cut through the area. Only after the reunification with the redevelopment of Potsdamer Platz, the construction of numerous shopping centers, government ministries, office buildings and entertainment venues, was the area revived.
In Frankfurt, there is a business district, in the geographical centre of the city and it is called the Bankenviertel. In Düsseldorf, there is a business district, located around the famous High-Street Königsallee with banks and offices. In Hong Kong, Sheung Wan and Causeway Bay are considered as the central business districts of Victoria City; the Yau Tsim Mong District has been considered the city centre of Kowloon before another core emerged in Cheung Sha Wan. As part of the Airport Core Programme, the Union Square project launched by the MTR Corporation has brought it another CBD in West Kowloon. With the latest implementation of "Energising Kowloon East" Scheme by the Hong Kong Government, Kowloon Bay and Kwun Tong Business Area have been redeveloped and transformed into CBDs; the CBDs of new towns and satellite cities such as Tuen Mun, Sha Tin and Tung Chung have been characterised by sky-scraping residential blocks on top of large shopping centres that provide services to local resi
According to the International Civil Aviation Organization, a runway is a "defined rectangular area on a land aerodrome prepared for the landing and takeoff of aircraft". Runways may be a natural surface. In January 1919, aviation pioneer Orville Wright underlined the need for "distinctly marked and prepared landing places, the preparing of the surface of reasonably flat ground an expensive undertaking there would be a continuous expense for the upkeep." Runways are named by a number between 01 and 36, the magnetic azimuth of the runway's heading in decadegrees. This heading differs from true north by the local magnetic declination. A runway numbered 09 points east, runway 18 is south, runway 27 points west and runway 36 points to the north; when taking off from or landing on runway 09, a plane is heading around 90°. A runway can be used in both directions, is named for each direction separately: e.g. "runway 15" in one direction is "runway 33" when used in the other. The two numbers differ by 18.
For clarity in radio communications, each digit in the runway name is pronounced individually: runway one-five, runway three-three, etc.. A leading zero, for example in "runway zero-six" or "runway zero-one-left", is included for all ICAO and some U. S. military airports. However, most U. S. civil aviation airports drop the leading zero. This includes some military airfields such as Cairns Army Airfield; this American anomaly may lead to inconsistencies in conversations between American pilots and controllers in other countries. It is common in a country such as Canada for a controller to clear an incoming American aircraft to, for example, runway 04, the pilot read back the clearance as runway 4. In flight simulation programs those of American origin might apply U. S. usage to airports around the world. For example, runway 05 at Halifax will appear on the program as the single digit 5 rather than 05. If there is more than one runway pointing in the same direction, each runway is identified by appending left and right to the number to identify its position — for example, runways one-five-left, one-five-center, one-five-right.
Runway zero-three-left becomes runway two-one-right. In some countries, regulations mandate that where parallel runways are too close to each other, only one may be used at a time under certain conditions. At large airports with four or more parallel runways some runway identifiers are shifted by 1 to avoid the ambiguity that would result with more than three parallel runways. For example, in Los Angeles, this system results in runways 6L, 6R, 7L, 7R though all four runways are parallel at 69°. At Dallas/Fort Worth International Airport, there are five parallel runways, named 17L, 17C, 17R, 18L, 18R, all oriented at a heading of 175.4°. An airport with only three parallel runways may use different runway identifiers, such as when a third parallel runway was opened at Phoenix Sky Harbor International Airport in 2000 to the south of existing 8R/26L — rather than confusingly becoming the "new" 8R/26L it was instead designated 7R/25L, with the former 8R/26L becoming 7L/25R and 8L/26R becoming 8/26.
Runway designations may change over time because Earth's magnetic lines drift on the surface and the magnetic direction changes. Depending on the airport location and how much drift occurs, it may be necessary to change the runway designation; as runways are designated with headings rounded to the nearest 10°, this affects some runways sooner than others. For example, if the magnetic heading of a runway is 233°, it is designated Runway 23. If the magnetic heading changes downwards by 5 degrees to 228°, the runway remains Runway 23. If on the other hand the original magnetic heading was 226°, the heading decreased by only 2 degrees to 224°, the runway becomes Runway 22; because magnetic drift itself is slow, runway designation changes are uncommon, not welcomed, as they require an accompanying change in aeronautical charts and descriptive documents. When runway designations do change at major airports, it is changed at night as taxiway signs need to be changed and the huge numbers at each end of the runway need to be repainted to the new runway designators.
In July 2009 for example, London Stansted Airport in the United Kingdom changed its runway designations from 05/23 to 04/22 during the night. For fixed-wing aircraft it is advantageous to perform takeoffs and landings into the wind to reduce takeoff or landing roll and reduce the ground speed needed to attain flying speed. Larger airports have several runways in different directions, so that one can be selected, most nearly aligned with the wind. Airports with one runway are constructed to be aligned with the prevailing wind. Compiling a wind rose is in fact one of the preliminary steps taken in constructing airport runways. Note that wind direction is given as the direction the wind is coming from: a plane taking off from runway 09 faces east, into an "east wind" blowing from 090°. Runway dimensions vary from as small as 245 m long and 8 m wide in s
Military aviation is the use of military aircraft and other flying machines for the purposes of conducting or enabling aerial warfare, including national airlift capacity to provide logistical supply to forces stationed in a theater or along a front. Airpower includes the national means of conducting such warfare, including the intersection of transport and war craft. Military aircraft include bombers, transports, trainer aircraft, reconnaissance aircraft; the first military uses of aviation involved lighter-than-air balloons. During the Battle of Fleurus in 1794, the French observation balloon l'Entreprenant was used to monitor Austrian troop movements; the use of lighter-than-air aircraft in warfare became prevalent in the 19th century, including regular use in the American Civil War. Lighter-than-air military aviation persisted until shortly after World War II being withdrawn from various roles as heavier-than-air aircraft improved. Heavier-than-air aircraft were recognized as having military applications early on, despite resistance from traditionalists and the severe limitations of early aircraft.
The U. S. Army Signal Corps purchased a Wright Model A on 2 August 1909 which became the first military aircraft in history. In 1911, the Italians used a variety of aircraft types in reconnaissance, photo-reconnaissance, bombing roles during the Italo-Turkish War. On October 23, 1911, an Italian pilot, Captain Carlo Piazza, flew over Turkish lines on the world's first aerial reconnaissance mission, on November 1, the first aerial bomb was dropped by Sottotenente Giulio Gavotti, on Turkish troops in Libya, from an early model of Etrich Taube aircraft; the Turks, lacking anti-aircraft weapons, were the first to shoot down an airplane by rifle fire. The earliest military role filled by aircraft was reconnaissance, however, by the end of World War I, military aviation had embraced many specialized roles, such as artillery spotting, air superiority, ground attack, anti-submarine patrols. Technological improvements were made at a frenzied pace, the first all-metal cantilevered airplanes were going into service as the war ended.
Between the major world wars incremental improvements made in many areas powerplants, aerodynamics and weapons, led to an more rapid advance in aircraft technology during World War II, with large performance increases and the introduction of aircraft into new roles, including Airborne Early Warning, electronic warfare, weather reconnaissance, flying lifeboats. Great Britain used aircraft to suppress revolts throughout the Empire during the interwar period and introduced the first military transports, which revolutionized logistics, allowing troops and supplies to be delivered over vastly greater distances. While they first appeared during World War I, ground attack aircraft didn't provide a decisive contribution until the Germans introduced Blitzkrieg during the Invasion of Poland and Battle of France, where aircraft functioned as mobile flying artillery to disrupt defensive formations; the Allies would use rocket-equipped fighters in the same role, immobilizing German armored divisions during the Battle of Normandy and afterwards.
World War I saw the creation of the first strategic bomber units, they wouldn't be tested until the Spanish Civil War where the perceived effects of mass bombardment would encourage their widespread use during World War II. Carrier aviation first appeared during World War I, came to play a major role during World War II, with most major navies recognizing the aircraft carrier's advantages over the battleship and devoting massive resources to the building of new carriers. During World War II, U-boats threatened the ability of the Allies to transport troops and war materiel to Europe, spurring the development of long range Maritime patrol aircraft, whose capability of independently detecting and destroying submerged submarines was increased with new detection systems, including sonobuoys, Leigh Lights, radar, along with better weapons including homing torpedoes and improved depth charges; this played a major role in winning the Battle of the Atlantic. Aircraft played a much expanded role, with many notable engagements being decided through the use of military aircraft, such as the Battle of Britain or the attack on Pearl Harbor, the conclusion of the Pacific War against Japan was marked by two lone aircraft dropping the atomic bombs, devastating the cities of Hiroshima and Nagasaki.
The introduction of the jet engine, early missiles and computers are World War II advancements which are felt to the present day. Post World War II, the development of military aviation was spurred by the Cold War stand-off between the super-powers; the helicopter appeared late in World War II and matured into an indispensable part of military aviation, transporting troops and providing expanded anti-submarine capabilities to smaller warships, negating the need for large numbers of small carriers. The need to out-perform opponents pushed new technology and aircraft developments in the U. S. S. R. and the United States, among others, the Korean War and the Vietnam War tested the resulting designs. Incredible advances in electronics were made, starting with the first electronic computers during World War II and expanding from its original role of cryptography into communications, data processing, remotely piloted aircraft, many other roles until it has become an integral aspect of modern warfare.
In the early 1960s, missiles were expected to replace manned interceptors and the guns in other manned aircraft. They failed to live up to expectations as surface-to-air missiles lacked flexibility and were not as effective as manned
The kilometre, or kilometer is a unit of length in the metric system, equal to one thousand metres. It is now the measurement unit used for expressing distances between geographical places on land in most of the world. K is used in some English-speaking countries as an alternative for the word kilometre in colloquial writing and speech. A slang term for the kilometre in the US and UK military is klick. There are two common pronunciations for the word; the former follows a pattern in English whereby metric units are pronounced with the stress on the first syllable and the pronunciation of the actual base unit does not change irrespective of the prefix. It is preferred by the British Broadcasting Corporation and the Australian Broadcasting Corporation. Many scientists and other users in countries where the metric system is not used, use the pronunciation with stress on the second syllable; the latter pronunciation follows the stress pattern used for the names of measuring instruments. The problem with this reasoning, however, is that the word meter in those usages refers to a measuring device, not a unit of length.
The contrast is more obvious in countries using the British rather than American spelling of the word metre. When Australia introduced the metric system in 1975, the first pronunciation was declared official by the government's Metric Conversion Board. However, the Australian prime minister at the time, Gough Whitlam, insisted that the second pronunciation was the correct one because of the Greek origins of the two parts of the word. By the 8 May 1790 decree, the Constituent assembly ordered the French Academy of Sciences to develop a new measurement system. In August 1793, the French National Convention decreed the metre as the sole length measurement system in the French Republic; the first name of the kilometre was "Millaire". Although the metre was formally defined in 1799, the myriametre was preferred to the "kilometre" for everyday use; the term "myriamètre" appeared a number of times in the text of Develey's book Physique d'Emile: ou, Principes de la science de la nature, while the term kilometre only appeared in an appendix.
French maps published in 1835 had scales showing myriametres and "lieues de Poste". The Dutch gave it the local name of the mijl, it was only in 1867 that the term "kilometer" became the only official unit of measure in the Netherlands to represent 1000 metres. Two German textbooks dated 1842 and 1848 give a snapshot of the use of the kilometre across Europe - the kilometre was in use in the Netherlands and in Italy and the myriametre was in use in France. In 1935, the International Committee for Weights and Measures abolished the prefix "myria-" and with it the "myriametre", leaving the kilometre as the recognised unit of length for measurements of that magnitude. In the United Kingdom, road signs show distances in miles and location marker posts that are used for reference purposes by road engineers and emergency services show distance references in unspecified units which are kilometre-based; the advent of the mobile phone has been instrumental in the British Department for Transport authorising the use of driver location signs to convey the distance reference information of location marker posts to road users should they need to contact the emergency services.
In the US, the National Highway System Designation Act of 1995 prohibits the use of federal-aid highway funds to convert existing signs or purchase new signs with metric units. The Executive Director of the US Federal Highway Administration, Jeffrey Paniati, wrote in a 2008 memo: "Section 205 of the National Highway System Designation Act of 1995 prohibited us from requiring any State DOT to use the metric system during project development activities. Although the State DOT's had the option of using metric measurements or dual units, all of them abandoned metric measurements and reverted to sole use of inch-pound values." The Manual on Uniform Traffic Control Devices since 2000 is published in both metric and American Customary Units. Some sporting disciplines feature 1000 m races in major events, but in other disciplines though world records are catalogued, the one kilometre event remains a minority event; the world records for various sporting disciplines are: Conversion of units, for comparison with other units of length Cubic metre Metric prefix Mileage Odometer Orders of magnitude Square kilometre Media related to Distance indicators at Wikimedia Commons
Foreign-trade zones of the United States
In the United States, a foreign-trade zone is a geographical area, in a United States Port of Entry, where commercial merchandise, both domestic and foreign receives the same Customs treatment it would if it were outside the commerce of the United States. Another definition of an FTZ states that it is an isolated and policed area operated as a public utility, furnished with facilities for loading, handling, manipulating and exhibiting goods and for reshipping them by land, water or air. Merchandise of every description may be held in the zone without being subject to tariffs and other ad valorem taxes; this tariff and tax relief is designed to lower the costs of U. S.-based operations engaged in international trade and thereby create and retain the employment and capital investment opportunities that result from those operations. These special geographic areas – foreign-trade zones – are established "in or adjacent to" U. S. Ports of Entry and are under the supervision of the U. S. Customs and Border Protection under the United States Homeland Security Council.
Since 1986, U. S. Customs' oversight of FTZ operations has been conducted on an audit-inspection basis known as Compliance Reviews, whereby compliance is assured through audits and spot checks under a surety bond, rather than through on-site supervision by Customs personnel. There are over nearly 400 subzones in the United States; the U. S. foreign-trade zones program was created by the Foreign-Trade Zones Act of 1934. The Foreign-Trade Zones Act was one of two key pieces of legislation passed in 1934 in an attempt to mitigate some of the destructive effects of the Smoot-Hawley Tariffs, imposed in 1930; the Foreign-Trade Zones Act was created to "expedite and encourage foreign commerce" in the United States. Through World War II, manufacturing activity was allowed only on a limited basis. In 1950, the original act was amended to open up FTZs to manufacturing, but it had little impact until 1980. In that year, Congress again amended the act so that products manufactured in the zones would not be assessed on U.
S. value-added. This ensured that the only tariffs a producer inside the zone selling to U. S. customers would pay, would be on the raw materials imported into the zone. This "integrated" model, which replaced the previous "island" model, spurred growth in the U. S. foreign-trade zones program. U. S. FTZs pose multiple benefits, other than duty deferred and inverted tariff, which companies can use to benefit their bottom line. However, a majority of companies are not utilizing FTZs to their full potential because sometimes the unknown creates uncertainty; some of the benefits of operating a FTZ include: Improved inventory management Automated recordkeeping and document storage Increased visibility of the supply chain Improved cash flow Improved company compliance Lessened U. S. regulatory agency requirements for re-export Inverted tariff benefits exist when the duty rate for the overall finished good is lower than the duty rate of the component parts. Therefore, by manufacturing finished goods within an FTZ, US importers can take advantage of the inverted tariff duty rate, all while keeping manufacturing operations within the US.
Inverted tariff works when an importer with manufacturing authority within an FTZ is allowed to admit their components into the zone duty-free, manufacture the finished good, pay CBP duties on the foreign content in the finished good at the lower duty rate of the finished goods at the time of entry. The importer avoids paying the higher duty rate on the component parts and defers the lower duty payment on the value of the foreign content until the time of consumption in the commerce of the US. Inverted tariff is seen predominantly in the manufacturing industry, benefiting automotive, pharmaceutical, electronics, textile companies and many more. Any company in any industry can apply to be a part of an FTZ. Companies importing to the U. S. on a regular basis and in high volume are the main participants. It is a way to reduce importing costs and save money by participating in special Customs procedures and simplifies processes to run more efficient inventory control systems; the process to register into one used to be lengthy — 9 to 12 months, depending on the industry and if a FTZ is being created or if you are participating in one that exists.
This changed in 2011. Alternative Site Framework provides a streamlined process for foreign-trade zone grantees to expand operations within their given service area. Grantees that have transitioned over to ASF are granted 2,000 "virtual" acres to designate sites within their service area, sometimes as as thirty days; as opposed to the Traditional Site Framework, this ASF option doesn't require a grantee to go through a traditional boundary modification for expansion purposes. Companies now have the option to select between establishing their business in a Usage Driven Site or a Magnet Site. Usage-driven sites are sites within a grantee's service area, that must go through a designation and activation process with the grantee and the Foreign-Trade Zone Board prior to initiating operations. Under ASF, usage-driven sites replace the role that subzones once held – allowing companies to operate under FTZ status while being located outside of what used to be called "general purpose zones" or now known as magnet sites under ASF.
Magnet sites are industrial parks or multi-tenant sites within a grantee's service area, which have been designated by the Foreign-Trade Zone Board. Once a company that's established in said industrial park wants to operate as an FTZ, it must only go through the designation process with the