Misplaced Pages

#380619

37-571: By comparison, a typical narrow-body aircraft has a diameter of 3 to 4 m (10 to 13 ft), with a single aisle, and seats between two and six people abreast. Wide-body aircraft were originally designed for a combination of efficiency and passenger comfort and to increase the amount of cargo space. However, airlines quickly gave in to economic factors, and reduced the extra passenger space in order to insert more seats and increase revenue and profits. Wide-body aircraft are also used by commercial cargo airlines , along with other specialized uses. By

74-625: A fan diameter of 290 centimetres (116 in), slightly smaller than the GE90 engines on the Boeing 777. The Trent 900 is designed to fit into a Boeing 747-400F freighter for easier transport by air cargo . The interiors of aircraft, known as the aircraft cabin , have been undergoing evolution since the first passenger aircraft. Today, between one and four classes of travel are available on wide-body aircraft. Bar and lounge areas which were once installed on wide-body aircraft have mostly disappeared, but

111-691: A few have returned in first class or business class on the Airbus A340-600 , Boeing 777-300ER , and on the Airbus A380. Emirates has installed showers for first-class passengers on the A380; twenty-five minutes are allotted for use of the room, and the shower operates for a maximum of five minutes. Depending on how the airline configures the aircraft, the size and seat pitch of the airline seats will vary significantly. For example, aircraft scheduled for shorter flights are often configured at

148-449: A higher seat density than long-haul aircraft. Due to current economic pressures on the airline industry, high seating densities in the economy class cabin are likely to continue. In some of the largest single-deck wide-body aircraft, such as the Boeing 777, the extra space above the cabin is used for crew rest areas and galley storage. The term "jumbo jet" usually refers to the largest variants of wide-body airliners; examples include

185-477: A larger presented cross-section will have a higher drag than thinner bodies; sleek ("streamlined") objects have lower form drag. Form drag follows the drag equation , meaning that it increases with the square of the velocity, and thus becomes more important for high-speed aircraft. Form drag depends on the longitudinal section of the body. A prudent choice of body profile is essential for a low drag coefficient . Streamlines should be continuous, and separation of

222-601: A second aisle, the wider aircraft could accommodate as many as 10 seats across, but could also be easily converted to a freighter and carry two eight-by-eight freight pallets abreast. The engineers also opted for creating "stretched" versions of the DC-8 (61, 62 and 63 models), as well as longer versions of Boeing's 707 (-320B and 320C models) and 727 (-200 model); and Douglas' DC-9 (-30, -40, and -50 models), all of which were capable of accommodating more seats than their shorter predecessor versions. The wide-body age began in 1970 with

259-500: A twinjet. Most modern wide-body aircraft have two engines, although the heaviest wide-body aircraft, the Airbus A380 and the Boeing 747-8, are built with four engines. The upcoming Boeing 777X-9 twinjet is approaching the capacity of the earlier Boeing 747. The Boeing 777 twinjet features the most powerful jet engine, the General Electric GE90 . The early variants have a fan diameter of 312 centimetres (123 in), and

296-402: Is an airliner arranged along a single aisle, permitting up to 6-abreast seating in a cabin less than 4 metres (13 ft) in width. In contrast, a wide-body aircraft is a larger airliner usually configured with multiple aisles and a fuselage diameter of more than 5 metres (16 ft), allowing at least seven-abreast seating and often more travel classes . Historically, beginning in

333-419: Is caused by viscous drag in the boundary layer around the object. The boundary layer at the front of the object is usually laminar and relatively thin, but becomes turbulent and thicker towards the rear. The position of the transition point from laminar to turbulent flow depends on the shape of the object. There are two ways to decrease friction drag: the first is to shape the moving body so that laminar flow

370-409: Is made up of parasitic drag and lift-induced drag . Parasitic drag is named as such because it is not useful, whereas lift-induced drag is the result of an airfoil generating lift. Parasitic drag comprises all types of drag except lift-induced drag. Form drag arises because of the shape of the object. The general size and shape of the body are the most important factors in form drag; bodies with

407-480: Is possible. The second method is to increase the length and decrease the cross-section of the moving object as much as practicable. To do so, a designer can consider the fineness ratio , which is the length of the aircraft divided by its diameter at the widest point (L/D). It is mostly kept 6:1 for subsonic flows. Increase in length increases Reynolds number ( R e {\displaystyle Re} ). With R e {\displaystyle Re} in

SECTION 10

#1732797274381

444-541: Is the local wall shear stress , and q is the free-stream dynamic pressure . For boundary layers without a pressure gradient in the x direction, it is related to the momentum thickness as For comparison, the turbulent empirical relation known as the One-seventh Power Law (derived by Theodore von Kármán ) is: where R e {\displaystyle Re} is the Reynolds number. For

481-1434: The Airbus A318 , while the Airbus A321LR could replace the less fuel efficient Boeing 757s used since their production ended in 2004. Boeing will face competition and pricing pressure from the Embraer E-Jet E2 family , Airbus A220 (formerly Bombardier CSeries) and Comac C919 . Between 2016 and 2035, FlightGlobal expects 26,860 single-aisles to be delivered for almost $ 1380 billion, 45% Airbus A320 family ceo and neo and 43% Boeing 737 NG and max. By June 2018, there were 10,572 Airbus A320neo and Boeing 737 MAX orders: 6,068 Airbuses (57%, 2,295 with CFMs, 1,623 with PWs and 2,150 with not yet decided engines) and 4,504 Boeings (43%); 3,446 in Asia-Pacific (33%), 2,349 in Europe (22%), 1,926 in North America (18%), 912 in Latin America (9%), 654 in Middle East (6%), 72 in Africa (1%) and 1,213 not yet bounded (11%). Many airlines have shown interest in

518-500: The Airbus A321LR or its A321XLR derivative, and other extended-range models, for thin transatlantic and Asia-Pacific routes. Form drag Parasitic drag , also known as profile drag , is a type of aerodynamic drag that acts on any object when the object is moving through a fluid. Parasitic drag is a combination of form drag and skin friction drag . It affects all objects regardless of whether they are capable of generating lift . Total drag on an aircraft

555-599: The Boeing 747 (the first wide-body and original "jumbo jet"), Airbus A380 ("superjumbo jet"), and Boeing 777-9 . The phrase "jumbo jet" derives from Jumbo , a circus elephant in the 19th century. Aircraft are categorized by ICAO according to the wake turbulence they produce. Because wake turbulence is generally related to the weight of an aircraft, these categories are based on one of four weight categories: light, medium, heavy, and super. Due to their weight, all current wide-body aircraft are categorized as " heavy ", or in

592-671: The Boeing 787 Dreamliner and Airbus A350 XWB . The proposed Comac C929 and C939 may also share this new wide-body market. The production of the large Boeing 747-8 and Airbus A380 four-engine, long-haul jets has come to an end as airlines are now preferring the smaller, more efficient Airbus A350, Boeing 787 and Boeing 777 twin-engine, long-range airliners. Although wide-body aircraft have larger frontal areas (and thus greater form drag ) than narrow-body aircraft of similar capacity, they have several advantages over their narrow-body counterparts, such as: British and Russian designers had proposed wide-body aircraft similar in configuration to

629-567: The Vickers VC10 and Douglas DC-9 , but with a wide-body fuselage. The British BAC Three-Eleven project did not proceed due to lack of government backing, while the Russian Ilyushin Il-86 wide-body proposal eventually gave way to a more conventional wing-mounted engine design, most likely due to the inefficiencies of mounting such large engines on the aft fuselage. As jet engine power and reliability have increased over

666-499: The 1960s, it was also believed that supersonic airliners would succeed larger, slower planes. Thus, it was believed that most subsonic aircraft would become obsolete for passenger travel and would be eventually converted to freighters. As a result, airline manufacturers opted for a wider fuselage rather than a taller one (the 747 , and eventually the McDonnell Douglas DC-10 and Lockheed L-1011 TriStar ). By adding

703-402: The 3,000 miles transatlantic flights between the eastern U.S. and Western Europe, previously dominated by wide-body aircraft. Norwegian Air Shuttle , JetBlue and TAP Portugal will open up direct routes bypassing airline hubs for lower fares between cheaper, smaller airports. The Boeing 737NG 3,300-mile range is insufficient for fully laden operations and operates at reduced capacity like

740-406: The 707 and DC-8 seated passengers along either side of a single aisle, with no more than six seats per row. Larger aircraft would have to be longer, higher ( double-deck aircraft ), or wider in order to accommodate a greater number of passenger seats. Engineers realized having two decks created difficulties in meeting emergency evacuation regulations with the technology available at that time. During

777-495: The Boeing 747 was not surpassed until October 2007, when the Airbus A380 entered commercial service with the nickname "Superjumbo". Both the Boeing 747 and Airbus A380 "jumbo jets" have four engines each (quad-jets), but the upcoming Boeing 777X ("mini jumbo jet") is a twinjet. In the mid-2000s, rising oil costs in a post- 9/11 climate caused airlines to look towards newer, more fuel-efficient aircraft. Two such examples are

SECTION 20

#1732797274381

814-662: The DC-10-based Tanker 910 and the 747-200 -based Evergreen Supertanker . Some wide-body aircraft are used as VIP transport. To transport those holding the highest offices, Canada uses the Airbus A310 , while Russia uses the Ilyushin Il-96 . Germany replaced its Airbus A310 with an Airbus A340 in spring 2011. Specially-modified Boeing 747-200s ( Boeing VC-25s ) are used to transport the President of

851-673: The United States . Some wide-body aircraft have been modified to enable transport of oversize cargo . Examples include the Airbus Beluga , Airbus BelugaXL and Boeing Dreamlifter . Two specially modified Boeing 747s were used to transport the U.S. Space Shuttle , while the Antonov An-225 was initially built to carry the Buran shuttle . Narrow-body aircraft A narrow-body aircraft or single-aisle aircraft

888-659: The aircraft to Aeroflot. However, in 1976 the Soviet Union launched its own first four-engined wide-body, the Ilyushin Il-86 . After the success of the early wide-body aircraft, several subsequent designs came to market over the next two decades, including the Boeing 767 and 777 , the Airbus A330 and Airbus A340 , and the McDonnell Douglas MD-11 . In the "jumbo" category, the capacity of

925-427: The body is dragging some amount of air with it. The force required to drag an "attached" layer of air with the body is called skin friction drag. Skin friction drag imparts some momentum to a mass of air as it passes through it and that air applies a retarding force on the body. As with other components of parasitic drag, skin friction follows the drag equation and rises with the square of the velocity . Skin friction

962-424: The boundary layer with its attendant vortices should be avoided. Form drag includes interference drag, caused by the mixing of airflow streams. For example, where the wing and fuselage meet at the wing root, two airstreams merge into one. This mixing can cause eddy currents, turbulence, or restrict smooth airflow. Interference drag is greater when two surfaces meet at perpendicular angles, and can be minimised by

999-558: The case of the A380 in U.S. airspace, "super". The wake-turbulence category also is used to guide the separation of aircraft. Super- and heavy-category aircraft require greater separation behind them than those in other categories. In some countries, such as the United States , it is a requirement to suffix the aircraft's call sign with the word heavy (or super ) when communicating with air traffic control in certain areas. Wide-body aircraft are used in science, research, and

1036-405: The core, then the engines may be shipped on a Boeing 747 Freighter. The General Electric GE9X , powering the Boeing 777X, is wider than the GE90 by 15 centimetres (6 in). The 560 tonnes (1,230,000 lb) maximum takeoff weight of the Airbus A380 would not have been possible without the engine technology developed for the Boeing 777 such as contra-rotating spools. Its Trent 900 engine has

1073-433: The denominator for skin friction coefficient's relation, as its value is increased (in laminar range), total friction drag is reduced. While decrease in cross-sectional area decreases drag force on the body as the disturbance in air flow is less. The skin friction coefficient, C f {\displaystyle C_{f}} , is defined by where τ w {\displaystyle \tau _{w}}

1110-474: The end of 2017, nearly 8,800 wide-body airplanes had been delivered since 1969, with production peaking at 412 in 2015. Following the success of the Boeing 707 and Douglas DC-8 in the late 1950s and early 1960s, airlines began seeking larger aircraft to meet the rising global demand for air travel. Engineers were faced with many challenges as airlines demanded more passenger seats per aircraft, longer ranges and lower operating costs. Early jet aircraft such as

1147-679: The entry into service of the first wide-body airliner, the four-engined, partial double-deck Boeing 747 . New trijet wide-body aircraft soon followed, including the McDonnell Douglas DC-10 and the L-1011 TriStar. The first wide-body twinjet , the Airbus A300 , entered service in 1974. This period came to be known as the "wide-body wars". L-1011 TriStars were demonstrated in the USSR in 1974, as Lockheed sought to sell

Wide-body aircraft - Misplaced Pages Continue

1184-450: The friction of the fluid against the "skin" of the object that is moving through it. Skin friction arises from the interaction between the fluid and the skin of the body, and is directly related to the wetted surface, the area of the surface of the body that is in contact with the fluid. Air in contact with a body will stick to the body's surface and that layer will tend to stick to the next layer of air and that in turn to further layers, hence

1221-462: The larger GE90-115B has a fan diameter of 325 centimetres (128 in). This is almost as wide as the 3.30 metres (130 in) Fokker 100 fuselage. Complete GE90 engines can only be ferried by outsize cargo aircraft such as the Antonov An-124 , presenting logistics problems if a 777 is stranded in a place due to emergency diversions without the proper spare parts. If the fan is removed from

1258-492: The last decades, most of the wide-body aircraft built today have only two engines. A twinjet design is more fuel-efficient than a trijet or quadjet of similar size. The increased reliability of modern jet engines also allows aircraft to meet the ETOPS certification standard, which calculates reasonable safety margins for flights across oceans. The trijet design was dismissed due to higher maintenance and fuel costs compared to

1295-432: The late 1960s and continuing through the 1990s, twin engine narrow-body aircraft, such as the Boeing 737 Classic , McDonnell-Douglas MD-80 and Airbus A320 were primarily employed in short to medium-haul markets requiring neither the range nor the passenger-carrying capacity of that period's wide-body aircraft. The re-engined Boeing 737 MAX and Airbus A320neo jets offer 500 miles more range, allowing them to operate

1332-920: The military. Some wide-body aircraft are used as flying command posts by the military like the Ilyushin Il-80 or the Boeing E-4 , while the Boeing E-767 is used for airborne early warning and control . New military weapons are tested aboard wide-bodies, as in the laser weapons testing on the Boeing YAL-1 . Other wide-body aircraft are used as flying research stations, such as the joint German–U.S. Stratospheric Observatory for Infrared Astronomy (SOFIA). Airbus A340, Airbus A380, and Boeing 747 four-engine wide-body aircraft are used to test new generations of aircraft engines in flight. A few aircraft have also been converted for aerial firefighting , such as

1369-406: The use of fairings . Wave drag , also known as supersonic wave drag or compressibility drag, is a component of form drag caused by shock waves generated when an aircraft is moving at transonic and supersonic speeds. Form drag is a type of pressure drag, a term which also includes lift-induced drag. Form drag is pressure drag due to separation. Skin friction drag arises from

#380619