The Boeing 777 is a long-range, wide-body twin-engine jet airliner manufactured by Boeing Commercial Airplanes. It is the world's largest twinjet and is commonly referred to as the "Triple Seven". The aircraft has seating for over 300 passengers and has a range from 5,235 to 9,380 nautical miles (9,695 to 17,370 km), depending on model. Its distinguishing features include the largest-diameter turbofan engines of any aircraft, six wheels on each main landing gear, a circular fuselage cross-section, and blade-shaped tail cone. Developed in consultation with eight major airlines, the 777 was designed to replace older wide-body airliners and bridge the capacity difference between the 767 and 747. As Boeing's first fly-by-wire airliner, it has computer mediated controls; it is also the first entirely computer-designed commercial aircraft.
The 777 is produced in two fuselage lengths. The original 777-200 model first entered service in 1995, followed by the extended-range 777-200ER in 1997; the stretched 777-300, which is 33.3 ft (10.1 m) longer, began service in 1998. The longer-range 777-300ER and 777-200LR variants entered service in 2004 and 2006, respectively, while a freighter version, the 777F, debuted in 2009. Both longer-range versions and the freighter feature General Electric GE90 engines, as well as extended and raked wingtips. Other models are equipped with either the GE90, Pratt & Whitney PW4000, or Rolls-Royce Trent 800 engines. The 777-200LR ranks as the world's longest-range airliner and holds the record for longest distance flown by an unrefueled commercial aircraft, with the demonstrated capability to fly more than halfway around the world.
United Airlines first placed the 777 into commercial airline service in 1995. As of March 2011, 60 customers have placed orders for 1,209 aircraft of all variants, with 923 delivered. The most common variant used worldwide is the 777-200ER, with 415 aircraft delivered, and Emirates operates the largest 777 fleet, with 86 aircraft. The airliner has had one hull-loss accident, attributed to a Trent 800 engine fuel component, with no passenger fatalities as of 2011.
Through the 2000s, the 777 has emerged as one of its manufacturer's best-selling models. Because of rising fuel costs, airlines have acquired the type as a comparatively fuel-efficient alternative to other wide-body jets and have increasingly used the aircraft on long-haul, transoceanic routes. Direct market competitors include the Airbus A330-300 and the A340, with the upcoming A350 XWB and Boeing 787 Dreamliner programs currently in development.
The design phase for Boeing's new twinjet was different from the company's previous commercial jetliners. For the first time, eight major airlines – All Nippon Airways, American Airlines, British Airways, Cathay Pacific Airways, Delta Air Lines, Japan Airlines, Qantas, and United Airlines – had a role in the development of the airliner. This was a departure from industry practice, where manufacturers typically designed aircraft with minimal customer input. The eight airlines that contributed to the design process became known within Boeing as the "Working Together" group. At the first group meeting in January 1990, a 23-page questionnaire was distributed to the airlines, asking each what it wanted in the new design. 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. Boeing also selected its Everett factory in Washington, home of 747 production, as the final assembly site for the 777.
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 The development phase coincided with United's replacement program for its aging DC-10s. 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. ETOPS certification was also a priority for United, given the overwater portion of United's Hawaii routes. In January 1993, a team of United developers joined other airline teams and Boeing designers at the Everett factory. The 240 design teams, with up to 40 members each, addressed almost 1,500 design issues with individual aircraft components. 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, along with higher operating weight options for the basic aircraft.
The 777 was the first commercial aircraft to be designed entirely on computer. Each design drawing was created on a three-dimensional CAD software system known as CATIA (Computer-Aided Three-dimensional Interactive Application), sourced from Dassault Systemes and IBM. This allowed a virtual aircraft to be assembled, in simulation, to check for interferences and to verify proper fit of the many thousands of parts, thus reducing costly rework. 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 data outside of engineering. Boeing was initially not convinced of CATIA's abilities and built a physical mock-up of the nose section to verify its results. The test was so successful that additional mock-ups were canceled.
Boeing delivered the first 777 to United Airlines on May 15, 1995. The FAA awarded 180-minute ETOPS clearance ("ETOPS-180") for the Pratt & Whitney PW4084-engined aircraft on May 30, 1995, making it the first airliner to carry an ETOPS-180 rating at its entry into service. Longer ETOPS clearance of 207 minutes was approved the following October. The first commercial flight took place on June 7, 1995 from London Heathrow Airport to Dulles International Airport near Washington, D.C.
On November 12, 1995, Boeing delivered the first model with General Electric GE90-77B engines to British Airways, which placed the aircraft into service five days later. Initial service was affected by gearbox bearing wear issues, which caused the airline to temporarily withdraw its 777 fleet from transatlantic service in 1997. British Airways' aircraft returned to full service later that year, and General Electric subsequently announced engine upgrades.
The first Rolls-Royce Trent 877-powered aircraft was delivered to Thai Airways International on March 31, 1996, completing the introduction of the three powerplants initially developed for the airliner. Each engine-aircraft combination had secured ETOPS-180 certification from the point of entry into service. By June 1997, orders for the 777 numbered 323 from 25 airlines, including satisfied launch customers that had ordered additional aircraft. Operations performance data established the consistent capabilities of the twinjet over long-haul transoceanic routes, leading to additional sales. By 1998, dispatch reliability figures had reached a 99.96 percent rate of takeoff without delay due to technical issues, and the growing number of fleet hours approached 900,000.
After the initial model, Boeing developed the 777-200ER, an increased gross weight variant with greater range and payload capability. The −200ER first flew on October 7, 1996, received FAA and JAA certification on January 17, 1997, and entered service with British Airways on February 9, 1997. Offering greater long-haul performance, the variant became the most widely ordered version of the aircraft through the early 2000s. On April 2, 1997, a Malaysia Airlines −200ER named "Super Ranger" broke the great circle "distance without landing" record for an airliner by flying eastward from Boeing Field, Seattle to Kuala Lumpur, a distance of 10,823 nautical miles (20,044 km), in 21 hours and 23 minutes.
Following the introduction of the −200ER, Boeing turned its attention to a stretched version of the airliner. On October 16, 1997, the 777-300 made its first flight. At 242.4 ft (73.9 m) in length, the −300 became the longest airliner yet produced (until the A340-600), and had a 20 percent greater overall capacity than the standard length model. The −300 was awarded type certification simultaneously from the FAA and JAA on May 4, 1998, and entered service with launch customer Cathay Pacific on May 27, 1998.
From the start of the development program, Boeing had considered building ultra-long-range variants. Early plans centered on a 777-100X proposal, which would have been a shortened version of the −200 with reduced weight and increased range, similar to the 747SP. However, the −100X would have carried fewer passengers than the −200 while having similar operating costs, leading to a higher cost per seat. By the late 1990s, design plans shifted to longer-range versions of existing models. A more-powerful engine in the 100,000 lbf (440 kN) and higher thrust class was required, leading to active discussions between Boeing and the engine manufacturers. General Electric offered to develop the GE90-115B engine, while Rolls-Royce proposed developing the Trent 8104 engine. In 1999, Boeing announced an agreement with General Electric, beating out rival proposals. As part of the deal with General Electric, Boeing agreed that GE90 engines would be the only powerplants offered for new versions of the 777.
Boeing introduced a number of advanced technologies with the 777 design, including fully digital fly-by-wire controls, fully software-configurable avionics, Honeywell LCD glass cockpit flight displays, and the first use of a fiber optic avionics network on a commercial airliner. Boeing made use of work done on the cancelled Boeing 7J7 regional jet, which utilized similar versions of the chosen technologies. In 2003, Boeing began offering the option of cockpit electronic flight bag computer displays.
The 777 interior, also known as the Boeing Signature Interior, features curved panels, larger overhead bins, and indirect lighting. Seating options range from six abreast in first class up to 10 across in economy. At 15-inch (380 mm) by 10-inch (250 mm), the windows were the largest of any current commercial airliner until the 787. The cabin also features "Flexibility Zones", which entails deliberate placement of water, electrical, pneumatic, and other hook-ups throughout the interior space, allowing airlines to move seats, galleys, and lavatories quickly when adjusting cabin arrangements. Several aircraft have also been fitted with VIP interiors for non-airline use. Boeing engineers designed a new hydraulically damped toilet seat cover hinge that closes slowly.
In 2003, Boeing introduced overhead crew rests as an option on the 777. Located above the main cabin and connected via staircases, the forward flight crew rest contains two seats and two bunks, while the aft cabin crew rest features multiple bunks. The Signature Interior has since been adapted for other Boeing wide-body and narrow-body aircraft, including 737NG, 747–400, 757–300, and newer 767 models. The 747–8 and 767-400ER have also adopted the larger, more rounded windows of the 777.
The 777 Freighter (777F) is an all-cargo version of the twinjet. It shares features with the −200LR, using its airframe, engines, and fuel capacity. With a maximum payload of 226,000 lb (103,000 kg), cargo capacity is similar to the 243,000 lb (110,000 kg) of the 747-200F. The freighter has a range of 4,900 nmi (9,070 km) at maximum payload, although greater range is possible if less cargo weight is carried. As the aircraft promises improved operating economics compared to existing freighters, airlines have targeted the 777F as a replacement for older freighters including the 747-200F and MD-11F.
The first 777F was delivered to Air France on February 19, 2009. As of March 2011, 39 freighters had been delivered to eight different customers, with 44 unfilled orders.
In the 2000s Boeing has also been studying the conversion of 777-200ER and −200 passenger airliners into freighters, under the name 777 Boeing Converted Freighter or 777 BCF. The company has been in discussion with several airline customers and looks to offer the conversion beginning in 2011. Fedex, UPS Airlines, and GE Commercial Aviation Services are some potential customers.
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