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Boeing 777
Boeing 777
Aircraft landing approach. Front quarter view of twin-engine jet in flight with flaps and landing gear extended.
Boeing 777-200ER of United Airlines, one of the launch customers of the 777
Role Wide-body jet airliner
National origin United States
Manufacturer Boeing Commercial Airplanes
First flight June 12, 1994
Introduction June 7, 1995, with United Airlines
Status In service
Primary users Emirates
United Airlines
Air France
American Airlines
Produced 1993–present
Number built 1,313 through June 2015[1]
Unit cost
777-200ER: US$261.5 million[2]
777-200LR: US$296.0 million[2]
777-300ER: US$320.2 million[2]
777F: US$300.5 million[2]
Developed into Boeing 777X
The Boeing 777 is a family of long-range wide-body twin-engine jet airliners developed and manufactured by Boeing Commercial Airplanes. It is the world's largest twinjet and has a typical seating capacity for 314 to 451 passengers, with a range of 5,235 to 9,380 nautical miles (9,695 to 17,372 km). Commonly referred to as the "Triple Seven",[3][4] its distinguishing features include the largest-diameter turbofan engines of any aircraft, six wheels on each main landing gear, fully circular fuselage cross-section,[5] and a blade-shaped tail cone.[6] Developed in consultation with eight major airlines, the 777 was designed to replace older wide-body airliners and bridge the capacity difference between Boeing's 767 and 747. As Boeing's first fly-by-wire airliner, it has computer-mediated controls. It is also the first entirely computer-aided designed commercial aircraft.
The 777 is produced in two fuselage lengths as of 2014. The original 777-200 variant entered commercial service in 1995, followed by the extended-range 777-200ER in 1997. The stretched 777-300, which is 33.25 ft (10.1 m) longer, followed in 1998. The longer-range 777-300ER and 777-200LR variants entered service in 2004 and 2006 respectively, while the 777F, a freighter version, debuted in February 2009; these variants all feature General Electric GE90 engines and extended raked wingtips. The earlier 777-200, -200ER and -300 versions are equipped with GE90, Pratt & Whitney PW4000, or Rolls-Royce Trent 800 engines. The 777-200LR is the world's longest-range airliner, able to fly over halfway around the globe, and holds the record for the longest distance flown non-stop by a commercial aircraft.[7][8]
The 777 first entered commercial service with United Airlines on June 7, 1995. It has received more orders than any other wide-body airliner; as of May 2015, 60 customers had placed orders for 1,852 aircraft of all variants, with 1,304 delivered.[1] The most common and successful variant is the 777-300ER with 570 delivered and 786 orders;[1] Emirates operates the largest 777 fleet, with 138 passenger and freighter aircraft as of July 2014.[9] The 777 has been involved in five hull-loss accidents as of July 2014; the Asiana Airlines Flight 214 accident in July 2013 was its first fatal crash in 18 years of service.
The 777 ranks as one of Boeing's best-selling models. Airlines have acquired the type as a comparatively fuel-efficient alternative to other wide-body jets and have increasingly deployed the aircraft on long-haul transoceanic routes. Direct market competitors include the Airbus A330-300, newly launched Airbus A350 XWB, and the out-of-production A340 and McDonnell Douglas MD-11. The 787 Dreamliner, which entered service in 2011, shares design features with the 777. In November 2013, Boeing announced the development of upgraded 777-8X and 777-9X models, collectively named 777X, featuring composite wings and GE9X engines and further technologies developed for the 787. The 777X series is planned to enter service by 2020.
Contents
Development
Background
Design effort
Production and testing
Entry into service
Initial derivatives
Longer-range models
Production updates and improvements
777X program
Design
Fly-by-wire
Airframe and systems
Interior
Variants
777-200
777-200ER
777-300
777-200LR
777-300ER
777 Freighter
777-8X and -9X
Government and corporate
Operators
Orders and deliveries
Incidents and accidents
Specifications
See also
References
Citations
Bibliography
External links
DevelopmentEdit
Background Edit
In the early 1970s, the Boeing 747, McDonnell Douglas DC-10, and the Lockheed L-1011 TriStar became the first generation of wide-body passenger airliners to enter service.[10] In 1978, Boeing unveiled three new models: the twin-engine Boeing 757 to replace its venerable 727, the twin-engine 767 to challenge the Airbus A300, and a trijet 777 concept to compete with the DC-10 and L-1011.[11][12][13] The mid-size 757 and 767 launched to market success, due in part to 1980s extended-range twin-engine operational performance standards (ETOPS) regulations governing transoceanic twinjet operations.[14] These regulations allowed twin-engine airliners to make ocean crossings at up to three hours' distance from emergency diversionary airports.[15] Under ETOPS rules, airlines began operating the 767 on long-distance overseas routes that did not require the capacity of larger airliners.[14] The trijet 777 was later dropped, following marketing studies that favored the 757 and 767 variants.[16] Boeing was left with a size and range gap in its product line between the 767-300ER and the 747-400.[17]
By the late 1980s, DC-10 and L-1011 models were approaching retirement age, prompting manufacturers to develop replacement designs.[18] McDonnell Douglas was working on the MD-11, a stretched and upgraded successor of the DC-10,[18] while Airbus was developing their A330 and A340.[18] In 1986, Boeing unveiled proposals for an enlarged 767, tentatively named 767-X,[19] to target the replacement market for first-generation wide-bodies like the DC-10,[15] and to complement existing 767 and 747 models in the company lineup.[20] The initial proposal featured a longer fuselage and larger wings than the existing 767,[19] along with winglets.[21] Later plans expanded the fuselage cross-section but retained the existing 767 flight deck, nose, and other elements.[19]
Airline customers were unimpressed with the 767-X proposals, and instead wanted an even wider fuselage cross-section, fully flexible interior configurations, short- to intercontinental-range capability, and an operating cost lower than any 767 stretch.[15] Airline planners' requirements for larger aircraft had become increasingly specific, adding to the heightened competition among aircraft manufacturers.[18] By 1988, Boeing realized that the only answer was a new design, which became the 777 twinjet.[22] The company opted for the twin-engine configuration given past design successes, projected engine developments, and reduced-cost benefits.[23] On December 8, 1989, Boeing began issuing offers to airlines for the 777.[19]
Design effort Edit
A flight deck, from behind the two pilots' seats. A center console lies in between the seats, in front is an instrument panel with several displays, and light enters through the forward windows.
Glass cockpit of a Transaero Airlines 777-200ER
The design phase for the new twinjet was different from Boeing's previous commercial jetliners. For the first time, eight major airlines – All Nippon Airways, American Airlines, British Airways, Cathay Pacific, Delta Air Lines, Japan Airlines, Qantas, and United Airlines – had a role in the development.[24] This was a departure from industry practice, where manufacturers typically designed aircraft with minimal customer input.[12] The eight airlines that contributed to the design process became known within Boeing as the "Working Together" group.[24] At the first group meeting in January 1990, a 23-page questionnaire was distributed to the airlines, asking what each wanted in the design.[15] By March 1990, Boeing and the airlines had decided upon a basic design configuration: a cabin cross-section close to the 747's, capacity up to 325 passengers, flexible interiors, a glass cockpit, fly-by-wire controls, and 10 percent better seat-mile costs than the A330 and MD-11.[15] Boeing selected its Everett factory in Washington, home of 747 production, as the 777's final assembly site.[25]
On October 14, 1990, United Airlines became the 777's launch customer when it placed an order for 34 Pratt & Whitney-powered aircraft valued at US$11 billion with options on an additional 34.[26][27] The development phase coincided with United's replacement program for its aging DC-10s.[28] United required that the new aircraft be capable of flying three different routes: Chicago to Hawaii, Chicago to Europe, and non-stop from Denver, a hot and high airport, to Hawaii.[28] ETOPS certification was also a priority for United,[29] given the overwater portion of United's Hawaii routes.[26] In January 1993, a team of United developers joined other airline teams and Boeing designers at the Everett factory.[30] The 240 design teams, with up to 40 members each, addressed almost 1,500 design issues with individual aircraft components.[31] The fuselage diameter was increased to suit Cathay Pacific, the baseline model grew longer for All Nippon Airways, and British Airways' input led to added built-in testing and interior flexibility,[15] along with higher operating weight options.[32]
The 777 was the first commercial aircraft designed entirely by computer.[20][26][33] Each design drawing was created on a three-dimensional CAD software system known as CATIA, sourced from Dassault Systemes and IBM.[34] This lets engineers assemble a virtual aircraft, in simulation, to check for interference and verify that the thousands of parts fit properly—thus reducing costly rework.[35] Boeing developed their own high-performance visualization system, FlyThru, later called IVT (Integrated Visualization Tool) to support large-scale collaborative engineering design reviews, production illustrations, and other uses of the CAD