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Originally envisioned in 1964, the initial 737-100 first flew in 1967, and entered airline service in February 1968. It was followed by the lengthened 737-200, which entered service in April 1968. In the 1980s, Boeing launched the -300, -400, and -500 models, subsequently referred to as the Boeing 737 Classic series. The 737 Classics added capacity and incorporated CFM56 turbofan engines along with wing improvements. In the 1990s, Boeing introduced the 737 Next Generation with multiple changes including a redesigned wing, upgraded cockpit, and new interior. The 737 Next Generation comprises the four -600, -700, -800, and -900ER models, ranging from 102 ft (31.09 m) to 138 ft (42.06 m) in length. Boeing Business Jet versions of the 737 Next Generation are also produced.
The 737 series is the best-selling jet airliner in the history of aviation. The 737 has been continuously manufactured by Boeing since 1967 with 6,638 aircraft delivered and 2,186 orders yet to be fulfilled as of December 2010. 737 assembly is centered at the Boeing Renton Factory in Renton, Washington. Many 737s serve markets previously filled by 707, 727, 757, DC-9, and MD-80/90 airliners, and the aircraft currently competes primarily with the Airbus A320 family. There are on average 1,250 737s airborne at any given time, with two departing or landing somewhere every five seconds.
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The first member of the A320 family—the A320—was launched in March 1984, first flew on 22 February 1987, and was first delivered in 1988. The family was soon extended to include the A321 (first delivered 1994), the A319 (1996), and the A318 (2003). The A320 family pioneered the use of digital fly-by-wire flight control systems, as well as side stick controls, in commercial aircraft. Although there has been a continuous improvement process since introduction, the proposed A320neo is to offer new, more efficient engines.
As of 30 March 2011, a total of 4,619 Airbus A320 family aircraft have been delivered, of which 4,532 are in active service. In addition, another 2,306 airliners are on firm order. According to Airbus, it ranked as the world's fastest-selling jet airliner family according to records from 2005 to 2007, and as the best-selling single-generation aircraft programme. The family's direct competitors are the Boeing 737 and 757.
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The four-engine 747 uses a double deck configuration for part of its length. It is available in passenger, freighter and other versions. Boeing designed the 747's hump-like upper deck to serve as a first class lounge or (as is the general rule today) extra seating, and to allow the aircraft to be easily converted to a cargo carrier by removing seats and installing a front cargo door. Boeing did so because the company expected supersonic airliners (whose development was announced in the early 1960s) to render the 747 and other subsonic airliners obsolete, while believing that the demand for subsonic cargo aircraft would be robust into the future. The 747 in particular was expected to become obsolete after 400 were sold but it exceeded its critics' expectations with production passing the 1,000 mark in 1993. As of June 2010, 1,418 aircraft have been built, with 109 more in various configurations remaining on order.
The 747-400, the latest version in service, is among the fastest airliners in service with a high-subsonic cruise speed of Mach 0.85–0.855 (up to 570 mph, 920 km/h). It has an intercontinental range of 7,260 nautical miles (8,350 mi or 13,450 km). The 747-400 passenger version can accommodate 416 passengers in a typical three-class layout or 524 passengers in a typical two-class layout. The newest version of the aircraft, the 747-8, is in production and flight testing in late 2010. Deliveries of the 747-8F freighter version are scheduled to begin in mid-2011, with the 747-8I passenger version to follow in late 2011. The 747 is to be replaced by the Boeing Y3 (part of the Boeing Yellowstone Project) in the future.
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The A380's upper deck extends along the entire length of the fuselage, and its width is equivalent to that of a widebody aircraft. This allows for an A380-800's cabin with 5,146 square feet (478.1 m2) of floor space; 49% more floor space than the current next-largest airliner, the Boeing 747-400 with 3,453 square feet (320.8 m2), and provides seating for 525 people in a typical three-class configuration or up to 853 people in all-economy class configurations. The A380-800 has a design range of 15,200 km (8,200 nmi; 9,400 mi), sufficient to fly from New York to Hong Kong for example, and a cruising speed of Mach 0.85 (about 900 km/h or 560 mph at cruising altitude).
As of April 2011, 234 firm orders have been placed, of which 46 had been delivered. The largest operator of the type is Emirates, which has 90 aircraft on order.
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The aircraft's initial designation was 7E7, prior to its renaming in January 2005. The first 787 was unveiled in a roll-out ceremony on July 8, 2007, at Boeing's Everett assembly factory, by which time it had become the fastest-selling wide-body airliner in history with 677 orders. By March 2011, 835 Boeing 787s had been ordered by 56 customers. As of 2011, launch customer All Nippon Airways has the largest number of 787s on order.
The 787 development and production has involved a large-scale collaboration with numerous suppliers around the globe. It is being assembled at the Boeing Everett Factory in Everett, Washington. Aircraft will also be assembled at a new factory in North Charleston, South Carolina. Both sites will deliver 787s to airline customers. Originally planned to enter service in May 2008, the project has suffered from repeated delays and is now more than three years behind schedule. The airliner's maiden flight took place on December 15, 2009, and it is currently undergoing flight testing with a goal of receiving certification in mid-2011 and entering service with All Nippon Airways in the third quarter of 2011.
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