| Boeing B747 | |
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The Boeing 747 is a widebody commercial airliner and cargo transport, often referred to by the nickname Jumbo Jet or Queen of the Skies. It is among the world's most recognizable aircraft, and was the first widebody ever produced. Manufactured by Boeing's Commercial Airplane unit in the United States, the original version of the 747 was two and a half times the size of the Boeing 707, one of the common large commercial aircraft of the 1960s. First flown commercially in 1970, the 747 held the passenger capacity record for 37 years.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 (567 mph or 913 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 next version of the aircraft, the 747-8, is in production and the freighter version (747-8F) is scheduled to enter service at the end of 2010 followed by the passenger version (747-8I) in 2011. The 747 is to be replaced by the Boeing Y3 (part of the Boeing Yellowstone Project) in the future. |
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| After the initial 747-100 model, Boeing developed the higher Maximum Takeoff Weight -100B variant and higher passenger capacity -100SR (Short Range) variant. Increased maximum takeoff weight (MTOW) can allow an aircraft to carry more fuel and have longer range. The -200 model followed, entering service in 1971. It featured more powerful engines and higher takeoff weight. Passenger, freighter and combination passenger-freighter versions were produced. The shortened 747SP (special performance) with a longer range was also developed in the mid-1970s. The 747 line was further developed with the launching of the 747-300 in 1980. The -300 resulted from Boeing studies to increase the seating capacity of the 747. Solutions such as fuselage plugs and extending the upper deck over the entire length of the fuselage were rejected. The early designation of the -300 was 747SUD for "stretched upper deck", then 747-200 SUD, followed by 747EUD, before the 747-300 designation was used. The 300 model was first produced in 1983. It included a stretched upper deck (SUD), increased cruise speed and increased seating capacity. Passenger, short range and combination freighter-passenger versions were produced. 1985, development of the longer range 747-400 was begun. The new variant had a new glass cockpit, which allowed for a cockpit crew of two instead of three. Development cost soared, and production delays occurred as new technologies were incorporated at the request of airlines. Insufficient workforce experience and reliance on overtime contributed to early production problems on the 747-400.The -400 entered service in 1989.In 1991, a record-breaking 1,087 passengers were airlifted aboard a 747 to Israel as part of Operation Solomon. | |
Since the arrival of the 747-400, several stretching schemes for the 747 have been proposed. Boeing announced the larger 747-500X and -600X designs in 1996. The new variants would have cost more than $5 billion to develop, and interest was not sufficient to launch the program. Boeing offered the more modest 747X and 747X stretch derivatives in 2000 as alternatives to the Airbus A3XX. However, the 747X family was unable to attract enough interest to enter production. Boeing switched from the 747X studies to pursue the Sonic Cruiser in 2001 and, after the Sonic Cruiser program was put on hold, the 787. Some of the ideas developed for the 747X were used on the 747-400ER. |
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2024 (c) |
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