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V formation

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A V formation is a symmetric V - or chevron -shaped flight formation . In nature, it occurs among geese , swans , ducks , and other migratory birds , improving their energy efficiency , while in human aviation , it is used mostly in military aviation , air shows , and occasionally commercial aviation .

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74-417: Flying in the V formation improves energy efficiency. Usually, large birds fly in this formation since smaller birds create more complex wind currents that are hard for the back members to take advantage of. V formations also improve the fuel efficiency of aircraft . The V formation possibly improves the efficiency of flying birds, particularly over long migratory routes. This allows the birds after to take

148-403: A helicopter . The fuel economy of an automobile relates to the distance traveled by a vehicle and the amount of fuel consumed . Consumption can be expressed in terms of the volume of fuel to travel a distance, or the distance traveled per unit volume of fuel consumed. Since fuel consumption of vehicles is a significant factor in air pollution, and since the importation of motor fuel can be

222-409: A 1970 paper, in a V formation of 25 members, each bird can achieve a reduction of induced drag and as a result increase their range by 71%. In a 2001 Nature study, researchers used trackers on pelicans and yielded the results that pelicans flying alone have higher heart rate and flap their wings more frequently compare to those flying in V formation. In a V formation, some birds prefer to fly at

296-407: A V formation. Since large aircraft at high speed generate immense vortices at their wings, two aircraft will fly approximately 1.5 to 2 miles apart, near the smooth current of updraft. Thus, significant fuel can be saved without compromising passenger comfort. Test flights were done using two AS350 Écureuil helicopters , and the results showed that 5 percent to 10 percent of fuel can be reduced for

370-460: A V shape. However, over time, they started learning how to fly in this formation as if they were self-taught or they learned by observing other ibises. The "V", or "Vic" formation is a basic flight formation for military aircraft in many air forces. The Vic formation is also common in ceremonial flyovers and airshow flights. Similar aerodynamics advantage was attempted to be utilized by engineers and research pilots. The airflow from wingtips of

444-568: A blend with conventional jet fuel. As of the end of 2017, four other pathways to SPK are certified, with their designations and maximum blend percentage in brackets: Hydroprocessed Esters and Fatty Acids (HEFA SPK, 50%); synthesized iso-paraffins from hydroprocessed fermented sugars (SIP, 10%); synthesized paraffinic kerosene plus aromatics (SPK/A, 50%); alcohol-to-jet SPK (ATJ-SPK, 30%). Both FT and HEFA based SPKs blended with JP-8 are specified in MIL-DTL-83133H. Some synthetic jet fuels show

518-617: A car and the production, transmission and storage of electricity and hydrogen, the label "zero pollution" applies only to the car's conversion of stored energy into movement. In 2004, a consortium of major auto-makers — BMW , General Motors , Honda , Toyota and Volkswagen / Audi — came up with "Top Tier Detergent Gasoline Standard" to gasoline brands in the US and Canada that meet their minimum standards for detergent content and do not contain metallic additives. Top Tier gasoline contains higher levels of detergent additives in order to prevent

592-399: A change in buying habits with a propensity to heavier vehicles that are less fuel-efficient. Energy efficiency is similar to fuel efficiency but the input is usually in units of energy such as megajoules (MJ), kilowatt-hours (kW·h), kilocalories (kcal) or British thermal units (BTU). The inverse of "energy efficiency" is " energy intensity ", or the amount of input energy required for

666-486: A diesel engine. See Brake-specific fuel consumption for more information. The energy efficiency in transport is the useful travelled distance , of passengers, goods or any type of load; divided by the total energy put into the transport propulsion means. The energy input might be rendered in several different types depending on the type of propulsion, and normally such energy is presented in liquid fuels , electrical energy or food energy . The energy efficiency

740-469: A heat value of a fuel, it would be trivial to convert from fuel units (such as litres of gasoline) to energy units (such as MJ) and conversely. But there are two problems with comparisons made using energy units: The specific energy content of a fuel is the heat energy obtained when a certain quantity is burned (such as a gallon, litre, kilogram). It is sometimes called the heat of combustion . There exists two different values of specific heat energy for

814-635: A high- octane gasoline known as avgas ) has a high volatility to improve its carburetion characteristics and high autoignition temperature to prevent preignition in high compression aircraft engines. Turbine engines (as with diesel engines ) can operate with a wide range of fuels because fuel is injected into the hot combustion chamber. Jet and gas turbine ( turboprop , helicopter ) aircraft engines typically use lower cost fuels with higher flash points , which are less flammable and therefore safer to transport and handle. The first axial compressor jet engine in widespread production and combat service,

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888-467: A large part of a nation's foreign trade , many countries impose requirements for fuel economy. Different methods are used to approximate the actual performance of the vehicle. The energy in fuel is required to overcome various losses ( wind resistance , tire drag , and others) encountered while propelling the vehicle, and in providing power to vehicle systems such as ignition or air conditioning. Various strategies can be employed to reduce losses at each of

962-423: A much slower rate and more efficiently than even a candle on Earth, and last much longer. Jet fuel Jet fuel or aviation turbine fuel ( ATF , also abbreviated avtur ) is a type of aviation fuel designed for use in aircraft powered by gas-turbine engines . It is colorless to straw-colored in appearance. The most commonly used fuels for commercial aviation are Jet A and Jet A-1, which are produced to

1036-502: A number of countries still using other systems, fuel economy is expressed in miles per gallon (mpg), for example in the US and usually also in the UK ( imperial gallon); there is sometimes confusion as the imperial gallon is 20% larger than the US gallon so that mpg values are not directly comparable. Traditionally, litres per mil were used in Norway and Sweden , but both have aligned to

1110-506: A process to make jet fuel from seawater. The technology requires an input of electrical energy to separate Oxygen (O 2 ) and Hydrogen (H 2 ) gas from seawater using an iron-based catalyst, followed by an oligomerization step wherein carbon monoxide (CO) and hydrogen are recombined into long-chain hydrocarbons, using zeolite as the catalyst. The technology is expected to be deployed in the 2020s by U.S. Navy warships, especially nuclear-powered aircraft carriers. On February 8, 2021,

1184-465: A reduction in pollutants such as SOx, NOx, particulate matter, and sometimes carbon emissions. It is envisaged that usage of synthetic jet fuels will increase air quality around airports which will be particularly advantageous at inner city airports. Qatar Airways became the first airline to operate a commercial flight on a 50:50 blend of synthetic Gas to Liquid (GTL) jet fuel and conventional jet fuel. The natural gas derived synthetic kerosene for

1258-669: A result, a few aircraft engine manufacturers, most notably Thielert and Austro Engine , have begun offering aircraft diesel engines which run on jet fuel which may simplify airport logistics by reducing the number of fuel types required. Jet fuel is available in most places in the world, whereas avgas is only widely available in a few countries which have a large number of general aviation aircraft. A diesel engine may be more fuel-efficient than an avgas engine. However, very few diesel aircraft engines have been certified by aviation authorities. Diesel aircraft engines are uncommon today, even though opposed-piston aviation diesel powerplants such as

1332-403: A series of hydrogen fueling stations has been established. Powered either through chemical reactions in a fuel cell that create electricity to drive very efficient electrical motors or by directly burning hydrogen in a combustion engine (near identically to a natural gas vehicle , and similarly compatible with both natural gas and gasoline); these vehicles promise to have near-zero pollution from

1406-459: A small combustion engine is combined with electric motors. Kinetic energy which would otherwise be lost to heat during braking is recaptured as electrical power to improve fuel efficiency. The larger batteries in these vehicles power the car's electronics , allowing the engine to shut off and avoid prolonged idling . Fleet efficiency describes the average efficiency of a population of vehicles. Technological advances in efficiency may be offset by

1480-413: A standardized international specification. The only other jet fuel commonly used in civilian turbine-engine powered aviation is Jet B, which is used for its enhanced cold-weather performance. Jet fuel is a mixture of a variety of hydrocarbons . Because the exact composition of jet fuel varies widely based on petroleum source, it is impossible to define jet fuel as a ratio of specific hydrocarbons. Jet fuel

1554-472: A unit of output such as MJ/passenger-km (of passenger transport), BTU/ton-mile or kJ/t-km (of freight transport), GJ/t (for production of steel and other materials), BTU/(kW·h) (for electricity generation), or litres/100 km (of vehicle travel). Litres per 100 km is also a measure of "energy intensity" where the input is measured by the amount of fuel and the output is measured by the distance travelled. For example: Fuel economy in automobiles . Given

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1628-572: Is a form of thermal efficiency , meaning the ratio of effort to result of a process that converts chemical potential energy contained in a carrier ( fuel ) into kinetic energy or work . Overall fuel efficiency may vary per device, which in turn may vary per application, and this spectrum of variance is often illustrated as a continuous energy profile . Non-transportation applications, such as industry , benefit from increased fuel efficiency, especially fossil fuel power plants or industries dealing with combustion , such as ammonia production during

1702-406: Is a naphtha-kerosene fuel that is used for its enhanced cold-weather performance. However, Jet B's lighter composition makes it more dangerous to handle. For this reason, it is rarely used, except in very cold climates. A blend of approximately 30% kerosene and 70% gasoline, it is known as wide-cut fuel. It has a very low freezing point of −60 °C (−76 °F), and a low flash point as well. It

1776-517: Is a popular topic in the field of artificial intelligence (AI) and machine learning (ML). The main factors representing and influencing driving behavior include velocity, acceleration, gear, road parameters, weather, etc. Simple things such as keeping tires properly inflated, having a vehicle well-maintained and avoiding idling can dramatically improve fuel efficiency. Careful use of acceleration and deceleration and especially limiting use of high speeds helps efficiency. The use of multiple such techniques

1850-401: Is also occasionally known as energy intensity . The inverse of the energy efficiency in transport is the energy consumption in transport. Energy efficiency in transport is often described in terms of fuel consumption , fuel consumption being the reciprocal of fuel economy. Nonetheless, fuel consumption is linked with a means of propulsion which uses liquid fuels , whilst energy efficiency

1924-548: Is applicable to any sort of propulsion. To avoid said confusion, and to be able to compare the energy efficiency in any type of vehicle, experts tend to measure the energy in the International System of Units , i.e., joules . Therefore, in the International System of Units, the energy efficiency in transport is measured in terms of metre per joule, or m/J, while the energy consumption in transport

1998-485: Is called " hypermiling ". The most efficient machines for converting energy to rotary motion are electric motors, as used in electric vehicles . However, electricity is not a primary energy source so the efficiency of the electricity production has also to be taken into account. Railway trains can be powered using electricity, delivered through an additional running rail, overhead catenary system or by on-board generators used in diesel-electric locomotives as common on

2072-476: Is considered one of the few customers of biofuels large enough to potentially bring biofuels up to the volume production needed to reduce costs. The U.S. Navy has also flown a Boeing F/A-18E/F Super Hornet dubbed the "Green Hornet" at 1.7 times the speed of sound using a biofuel blend. The Defense Advanced Research Projects Agency (DARPA) funded a $ 6.7 million project with Honeywell UOP to develop technologies to create jet fuels from biofeedstocks for use by

2146-400: Is dependent on many parameters of a vehicle, including its engine parameters, aerodynamic drag , weight, AC usage, fuel and rolling resistance . There have been advances in all areas of vehicle design in recent decades. Fuel efficiency of vehicles can also be improved by careful maintenance and driving habits. Hybrid vehicles use two or more power sources for propulsion. In many designs,

2220-443: Is measured in terms of joules per metre, or J/m. The more efficient the vehicle, the more metres it covers with one joule (more efficiency), or the fewer joules it uses to travel over one metre (less consumption). The energy efficiency in transport largely varies by means of transport. Different types of transport range from some hundred kilojoules per kilometre (kJ/km) for a bicycle to tens of megajoules per kilometre (MJ/km) for

2294-533: Is not formed and complete combustion occurs., National Aeronautics and Space Administration, April 2005. Experiments by NASA in microgravity reveal that diffusion flames in microgravity allow more soot to be completely oxidised after they are produced than diffusion flames on Earth, because of a series of mechanisms that behaved differently in microgravity when compared to normal gravity conditions. LSP-1 experiment results , National Aeronautics and Space Administration, April 2005. Premixed flames in microgravity burn at

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2368-584: Is primarily used in northern Canada and Alaska , where the extreme cold makes its low freezing point necessary, and which helps mitigate the danger of its lower flash point. TS-1 is a jet fuel made to Russian standard GOST 10227 for enhanced cold-weather performance. It has somewhat higher volatility than Jet A-1 (flash point is 28 °C (82 °F) minimum). It has a very low freezing point, below −50 °C (−58 °F). The DEF STAN 91-091 (UK) and ASTM D1655 (international) specifications allow for certain additives to be added to jet fuel, including: As

2442-399: Is the mandatory addition of an antistatic additive to Jet A-1 fuel. Jet A and Jet A-1 fuel trucks and storage tanks, as well as plumbing that carries them, are all marked "Jet A" or "Jet A-1" in white italicized text within a black rectangle background, adjacent to one or two diagonal black stripes. Jet A-1 fuel must meet: Jet A fuel must reach ASTM specification D1655 (Jet A). Jet B

2516-569: Is therefore defined as a performance specification rather than a chemical compound. Furthermore, the range of molecular mass between hydrocarbons (or different carbon numbers) is defined by the requirements for the product, such as the freezing point or smoke point. Kerosene -type jet fuel (including Jet A and Jet A-1, JP-5, and JP-8) has a carbon number distribution between about 8 and 16 (carbon atoms per molecule); wide-cut or naphtha -type jet fuel (including Jet B and JP-4), between about 5 and 15. Fuel for piston-engine powered aircraft (usually

2590-434: Is very low. This was reflected in a study by AEA Technology between a Eurostar train and airline journeys between London and Paris, which showed the trains on average emitting 10 times less CO 2 , per passenger, than planes, helped in part by French nuclear generation. In the future, hydrogen cars may be commercially available. Toyota is test-marketing vehicles powered by hydrogen fuel cells in southern California, where

2664-499: Is very similar to diesel fuel , and in some cases, may be used in diesel engines . The possibility of environmental legislation banning the use of leaded avgas (fuel in spark-ignited internal combustion engine, which usually contains tetraethyllead (TEL), a toxic substance added to prevent engine knocking ), and the lack of a replacement fuel with similar performance, has left aircraft designers and pilot's organizations searching for alternative engines for use in small aircraft. As

2738-531: The Haber process . In the context of transport , fuel economy is the energy efficiency of a particular vehicle, given as a ratio of distance traveled per unit of fuel consumed. It is dependent on several factors including engine efficiency , transmission design, and tire design. In most countries, using the metric system , fuel economy is stated as "fuel consumption" in liters per 100 kilometers (L/100 km) or kilometers per liter (km/L or kmpl). In

2812-641: The Junkers Jumo 004 used on the Messerschmitt Me 262A fighter and the Arado Ar 234B jet recon-bomber, burned either a special synthetic "J2" fuel or diesel fuel. Gasoline was a third option but unattractive due to high fuel consumption. Other fuels used were kerosene or kerosene and gasoline mixtures. Most jet fuels in use since the end of World War II are kerosene-based. Both British and American standards for jet fuels were first established at

2886-511: The Junkers Jumo 205 family had been used during the Second World War. Jet fuel is often used in diesel-powered ground-support vehicles at airports. However, jet fuel tends to have poor lubricating ability in comparison to diesel, which increases wear in fuel injection equipment. An additive may be required to restore its lubricity . Jet fuel is more expensive than diesel fuel but the logistical advantages of using one fuel can offset

2960-399: The latent heat of vaporization of water. The difference between the high and low values is significant, about 8 or 9%. This accounts for most of the apparent discrepancy in the heat value of gasoline. In the U.S. (and the table) the high heat values have traditionally been used, but in many other countries, the low heat values are commonly used. Neither the gross heat of combustion nor

3034-500: The upwash lift force due to the wingtip vortices at the tip of the wings of the lead bird. The upwash assists each bird in supporting its own weight in flight, in the same way a glider can climb or maintain height indefinitely in rising air. The birds are able to find the place where the uplift is the most desirable either by sight or by sensing the airflow by their feathers, scientists suspect. Previous studies found that birds can use less than 20 to 30 percent of energy. According to

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3108-662: The B-1B, B-52H, C-17, Lockheed Martin C-130J Super Hercules , McDonnell Douglas F-4 Phantom (as QF-4 target drones ), McDonnell Douglas F-15 Eagle , Lockheed Martin F-22 Raptor , and Northrop T-38 Talon to use the synthetic fuel blend. The U.S. Air Force's C-17 Globemaster III, F-16 and F-15 are certified for use of hydrotreated renewable jet fuels. The USAF plans to certify over 40 models for fuels derived from waste oils and plants by 2013. The U.S. Army

3182-457: The EU standard of L/100 km. Fuel consumption is a more accurate measure of a vehicle's performance because it is a linear relationship while fuel economy leads to distortions in efficiency improvements. Weight-specific efficiency (efficiency per unit weight) may be stated for freight , and passenger-specific efficiency (vehicle efficiency per passenger) for passenger vehicles. Fuel efficiency

3256-532: The State Standard ( GOST ) number, or a Technical Condition number, with the principal grade available being TS-1. Jet A specification fuel has been used in the United States since the 1950s and is usually not available outside the United States and a few Canadian airports such as Toronto , Montreal , and Vancouver , whereas Jet A-1 is the standard specification fuel used in most of the rest of

3330-525: The US and UK rail networks. Pollution produced from centralised generation of electricity is emitted at a distant power station, rather than "on site". Pollution can be reduced by using more railway electrification and low carbon power for electricity. Some railways, such as the French SNCF and Swiss federal railways derive most, if not 100% of their power, from hydroelectric or nuclear power stations, therefore atmospheric pollution from their rail networks

3404-692: The United States LSD is now only available to the off-road construction, locomotive and marine markets. As more EPA regulations are introduced, more refineries are hydrotreating their jet fuel production, thus limiting the lubricating abilities of jet fuel, as determined by ASTM Standard D445. JP-8 , which is similar to Jet A-1, is used in NATO diesel vehicles as part of the single-fuel policy. Fischer–Tropsch (FT) Synthesized Paraffinic Kerosene (SPK) synthetic fuels are certified for use in United States and international aviation fleets at up to 50% in

3478-820: The United States and NATO militaries. In April 2011, four USAF F-15E Strike Eagles flew over the Philadelphia Phillies opening ceremony using a blend of traditional jet fuel and synthetic biofuels. This flyover made history as it was the first flyover to use biofuels in the Department of Defense . The air transport industry is responsible for 2–3 percent of man-made carbon dioxide emitted. Boeing estimates that biofuels could reduce flight-related greenhouse-gas emissions by 60 to 80 percent. One possible solution which has received more media coverage than others would be blending synthetic fuel derived from algae with existing jet fuel: Solazyme produced

3552-484: The United States, ASTM International produces standards for civilian fuel types, and the U.S. Department of Defense produces standards for military use. The British Ministry of Defence establishes standards for both civil and military jet fuels. For reasons of inter-operational ability, British and United States military standards are harmonized to a degree. In Russia and the CIS members, grades of jet fuels are covered by

3626-619: The aircraft can provide upward lift force for the planes behind, providing more efficient flight. NASA’s Dryden Flight Research Center initiated the NASA Autonomous Formation Flight program, which involved a Formation Flight Instrumentation System that uses GPS to allow the aircraft to be position at precise formation location automatically. The goal of this program was to save a sustained 10 percent of fuel, and experimental data suggested that as high as 15 percent could be achieved. Such fuel reduction can also reduce

3700-519: The amount of pollution released into the environment. Air Mobility Command , which accounts for 20 percent of all avionic fuel usage by the United States federal government, is also experimenting with autopilot changes to find the best tradeoff between the reduced drag of 'vortex surfing' and the resulting 'ride qualities' of flying through another aircraft's wake. Airbus has made efforts to reduce fuel consumption in commercial aviation through its fello’fly project, where two commercial aircraft fly in

3774-420: The aviation industry's jet kerosene demands have increased to more than 5% of all refined products derived from crude, it has been necessary for the refiner to optimize the yield of jet kerosene, a high-value product, by varying process techniques. New processes have allowed flexibility in the choice of crudes, the use of coal tar sands as a source of molecules and the manufacture of synthetic blend stocks. Due to

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3848-422: The build-up of deposits (typically, on fuel injector and intake valve ) known to reduce fuel economy and engine performance. How fuel combusts affects how much energy is produced. The National Aeronautics and Space Administration (NASA) has investigated fuel consumption in microgravity . The common distribution of a flame under normal gravity conditions depends on convection , because soot tends to rise to

3922-495: The conversions between the chemical energy in the fuel and the kinetic energy of the vehicle. Driver behavior can affect fuel economy; maneuvers such as sudden acceleration and heavy braking waste energy. Energy-efficient driving techniques are used by drivers who wish to reduce their fuel consumption, and thus maximize fuel efficiency. Many drivers have the potential to improve their fuel efficiency significantly. The relationship between fuel consumption and driving behavior

3996-473: The detection of free water in jet fuel uses a water-sensitive filter pad that turns green if the fuel exceeds the specification limit of 30 ppm (parts per million) free water. A critical test to rate the ability of jet fuel to release emulsified water when passed through coalescing filters is ASTM standard D3948 Standard Test Method for Determining Water Separation Characteristics of Aviation Turbine Fuels by Portable Separometer. Military organizations around

4070-589: The end of World War II. British standards derived from standards for kerosene use for lamps—known as paraffin in the UK—whereas American standards derived from aviation gasoline practices. Over the subsequent years, details of specifications were adjusted, such as minimum freezing point, to balance performance requirements and availability of fuels. Very low temperature freezing points reduce the availability of fuel. Higher flash point products required for use on aircraft carriers are more expensive to produce. In

4144-473: The extra expense of its use in certain circumstances. Jet fuel contains more sulfur, up to 1,000 ppm, which therefore means it has better lubricity and does not currently require a lubricity additive as all pipeline diesel fuels require. The introduction of Ultra Low Sulfur Diesel or ULSD brought with it the need for lubricity modifiers. Pipeline diesels before ULSD were able to contain up to 500 ppm of sulfur and were called Low Sulfur Diesel or LSD. In

4218-505: The first six months of 2008, largely due to fuel costs. In 2015 ASTM approved a modification to Specification D1655 Standard Specification for Aviation Turbine Fuels to permit up to 50 ppm (50 mg/kg) of FAME ( fatty acid methyl ester ) in jet fuel to allow higher cross-contamination from biofuel production. Worldwide demand of jet fuel has been steadily increasing since 1980. Consumption more than tripled in 30 years from 1,837,000 barrels/day in 1980, to 5,220,000 in 2010. Around 30% of

4292-421: The left, some at the right, and some at the center. The birds flying at the tips and at the front are rotated in a timely cyclical fashion to spread flight fatigue equally among the flock members. Canada geese , ducks and swans commonly form a skein in V formation. Thus, the flight formation variates around a V-like shape and does not stay constant. Flying in V formation is not only about position but also about

4366-440: The low temperatures in the upper atmosphere . This causes precipitation of the dissolved water from the fuel. The separated water then drops to the bottom of the tank, because it is denser than the fuel. Since the water is no longer in solution, it can form droplets which can supercool to below 0 °C (32 °F). If these supercooled droplets collide with a surface they can freeze and may result in blocked fuel inlet pipes. This

4440-488: The net heat of combustion gives the theoretical amount of mechanical energy (work) that can be obtained from the reaction. (This is given by the change in Gibbs free energy , and is around 45.7 MJ/kg for gasoline.) The actual amount of mechanical work obtained from fuel (the inverse of the specific fuel consumption ) depends on the engine. A figure of 17.6 MJ/kg is possible with a gasoline engine, and 19.1 MJ/kg for

4514-405: The number and severity of the processes used, it is often necessary and sometimes mandatory to use additives. These additives may, for example, prevent the formation of harmful chemical species or improve a property of a fuel to prevent further engine wear. It is very important that jet fuel be free from water contamination . During flight, the temperature of the fuel in the tanks decreases, due to

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4588-682: The program to certify the Boeing C-17 Globemaster III and then the Rockwell B-1B Lancer to use the fuel. To test these two aircraft, the USAF has ordered 281,000 US gal (1,060,000 L) of FT fuel. The USAF intends to test and certify every airframe in its inventory to use the fuel by 2011. They will also supply over 9,000 US gal (34,000 L; 7,500 imp gal) to NASA for testing in various aircraft and engines. The USAF has certified

4662-426: The same batch of fuel. One is the high (or gross) heat of combustion and the other is the low (or net) heat of combustion. The high value is obtained when, after the combustion, the water in the exhaust is in liquid form. For the low value, the exhaust has all the water in vapor form (steam). Since water vapor gives up heat energy when it changes from vapor to liquid, the liquid water value is larger since it includes

4736-676: The second aircraft per trip. This percentage per flight means several tons of jet fuel and carbon dioxide emissions . Nevertheless, operational and financial concerns and savings between airlines need to be addressed, as well as the schedules of position and altitude data for planes with similar routes to fly together. This list is not comprehensive as it does not cover all birds that fly in V formation. Migrating birds real flight V-formation spatial configuration. Real Dataset from North German bird migration photo). [REDACTED] Media related to V formations at Wikimedia Commons Fuel efficiency Fuel efficiency (or fuel economy )

4810-486: The six-hour flight from London to Doha came from Shell's GTL plant in Bintulu , Malaysia . The world's first passenger aircraft flight to use only synthetic jet fuel was from Lanseria International Airport to Cape Town International Airport on September 22, 2010. The fuel was developed by Sasol . Chemist Heather Willauer is leading a team of researchers at the U.S. Naval Research Laboratory who are developing

4884-408: The tailpipe (exhaust pipe). Potentially the atmospheric pollution could be minimal, provided the hydrogen is made by electrolysis using electricity from non-polluting sources such as solar, wind or hydroelectricity or nuclear. Commercial hydrogen production uses fossil fuels and produces more carbon dioxide than hydrogen. Because there are pollutants involved in the manufacture and destruction of

4958-578: The test program. This program is part of the Department of Defense Assured Fuel Initiative, an effort to develop secure domestic sources for the military energy needs. The Pentagon hopes to reduce its use of crude oil from foreign producers and obtain about half of its aviation fuel from alternative sources by 2016. With the B-52 now approved to use the FT blend, the USAF will use the test protocols developed during

5032-452: The timing of flapping. The birds behind will sync with the flapping pattern of the leading bird to follow the trail of upwash left by the bird at front. Whenever a bird flies to be directly behind another, it will reverse the flapping pattern to counter the downwash force. Through an experiment with ibises , researchers found that flying in V formation is a skill that they were not born with. When they first flew together, they did not fly in

5106-435: The top of a flame, such as in a candle, making the flame yellow. In microgravity or zero gravity , such as an environment in outer space , convection no longer occurs, and the flame becomes spherical , with a tendency to become more blue and more efficient. There are several possible explanations for this difference, of which the most likely one given is the hypothesis that the temperature is evenly distributed enough that soot

5180-405: The world use a different classification system of JP (for "Jet Propellant") numbers. Some are almost identical to their civilian counterparts and differ only by the amounts of a few additives; Jet A-1 is similar to JP-8 , Jet B is similar to JP-4 . Other military fuels are highly specialized products and are developed for very specific applications. Jet fuel

5254-443: The world's first 100 percent algae-derived jet fuel, Solajet, for both commercial and military applications. Oil prices increased about fivefold from 2003 to 2008, raising fears that world petroleum production is becoming unable to keep up with demand . The fact that there are few alternatives to petroleum for aviation fuel adds urgency to the search for alternatives . Twenty-five airlines were bankrupted or stopped operations in

5328-456: The world's first scheduled passenger flight flew with some synthetic kerosene from a non-fossil fuel source. 500 liters of synthetic kerosene was mixed with regular jet fuel. Synthetic kerosene was produced by Shell and the flight was operated by KLM. On August 8, 2007, Air Force Secretary Michael Wynne certified the B-52H as fully approved to use the FT blend, marking the formal conclusion of

5402-414: The world, the main exceptions being Russia and the CIS members, where TS-1 fuel type is the most common standard. Both Jet A and Jet A-1 have a flash point higher than 38 °C (100 °F), with an autoignition temperature of 210 °C (410 °F). The differences between Jet A and Jet A-1 are twofold. The primary difference is the lower freezing point of Jet A-1 fuel: The other difference

5476-505: Was the cause of the British Airways Flight 38 accident. Removing all water from fuel is impractical; therefore, fuel heaters are usually used on commercial aircraft to prevent water in fuel from freezing. There are several methods for detecting water in jet fuel. A visual check may detect high concentrations of suspended water, as this will cause the fuel to become hazy in appearance. An industry standard chemical test for

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