From Wikipedia, the free encyclopedia
| Boeing 747 | |
|---|---|
 |
|
| Japan Airlines Boeing 747 | |
| Type | Airliner |
| Manufacturer | Boeing Commercial Airplanes |
| Designed by | Joe Sutter |
| Maiden flight | 1969-02-09[1] |
| Introduction | 1970 with Pan Am and TWA[1] |
| Status | In development (747-8) |
| Primary users | Japan Airlines (70) Air France-KLM (58) British Airways (57) Korean Air (42) |
| Produced | 1969–present |
| Number built | 1,380 as of 2006 |
| Unit cost | 747-100 $24,000,000 (1967) 747-200 $39,000,000 (1976) 747-300 $82,000,000 (1982) 747-400 $230,000,000 (2006) |
| Variants | Boeing 747SP Boeing VC-25 Boeing 747-400 Boeing 747-8 Boeing 747 LCF |
The Boeing 747, commonly nicknamed the "Jumbo Jet", is a long-haul, widebody commercial airliner manufactured by Boeing. Known for its impressive size, it is among the world's most recognizable aircraft. First flown commercially in 1970, it held the passenger capacity record for 35 years and was the first commercial wide-body aircraft.
The four-engine 747, produced by Boeing's Commercial Airplane unit, uses a double decker configuration for part of its length. A typical three-class layout accommodates 416 passengers, while a two-class layout accommodates a maximum of 524 passengers. The hump created by the upper deck has made the 747 a highly recognizable icon of air travel.
The 747 was expected to become obsolete after sales of 400 units, but it outlived many of its critics' expectations and production passed the 1,000 mark in 1993. As of the end of 2006, 1380 planes had been built with 120 more in various configurations on order. The latest incarnation of the aircraft will be the 747-8.[2]
[edit] Introduction
The 747-400, the latest version in service, flies at high-subsonic speeds of Mach 0.85 (567 mph or 913 km/h), and features an intercontinental range of 7,260 nm (8,355 mi, 13,446 km).[3] In some configurations this is sufficient to fly non-stop from New York to Hong Kong—a third of the way around the globe. In 1989, a Qantas 747-400 flew non-stop from London to Sydney, a distance of 9,720 nm (11,185 mi, 18,001 km) in 20 hours and 9 minutes, although this was a delivery flight with no passengers or freight aboard.[4]
The 747 is the second largest passenger airliner, after the Airbus A380. The 747 is the largest airliner presently in regular service. The Antonov An-225 cargo transport remains the world's largest aircraft by maximum gross takeoff weight in service, while the Hughes H-4 Hercules has a larger wing-span.[5] Only one each of the latter two aircraft were produced, while the 747 and A380 are for serial production.
[edit] History
[edit] Development
The 747 was born from the massive increase in air travel in the 1960s. The era of commercial jet transportation, led by the enormous popularity of the Boeing 707 and Douglas DC-8, had revolutionized long distance travel. Boeing had already developed a study for a very large fixed-wing aircraft while bidding on a US military contract for a huge cargo plane.[6] Even before it lost the contract to Lockheed's C-5 Galaxy in September 1965 Boeing came under pressure from Juan Trippe, president of its most loyal airline customer Pan Am, to build a giant passenger plane that would be over twice the size of the 707.
In 1965 Joe Sutter was transferred from Boeing's 737 development team to manage the studies for new airliner, already assigned its model number 747. The original design was a full-length double-decker fuselage seating eight across (3–2–3) on the lower deck and seven across (2–3–2) on the upper deck.[7] However, concern over evacuation routes and limited cargo carrying capability caused this idea to be scrapped in early 1966 favor of wider single deck, becoming the first wide-body airliner.[8]
One of the principal technologies which enabled an airplane as large as the 747 to be conceived was the high-bypass turbofan engine. This promised to deliver double the power of the earlier turbojets, while consuming one third less fuel. General Electric had pioneered the concept but were fully committed to developing the engine for the C-5 Galaxy. Pratt & Whitney were also working on the same principle, and by late 1966 Boeing, Pan-Am and Pratt & Whitney agreed that Pratt would develop a new engine, designated JT9D to power the 747. Four of these engines were mounted in pods below the 747's wings.
At the time, it was widely thought that the 747 would be superseded in the future by supersonic transport (SST) aircraft. So Boeing designed the 747 so that it could easily be adapted to carry freight, knowing that if and when sales of the passenger version dried up, the plane could remain in production as a cargo transport. The cockpit was therefore placed on a shortened upper deck so that a nose cone loading door could be included, thus creating the 747's distinctive "bulge". However, supersonic transports, including the Concorde and Boeing's never-produced 2707, were not widely adopted. SSTs were less fuel efficient at a time when fuel prices were soaring, very noisy during takeoff and landing, and their ability to operate at supersonic speeds over land was limited due to regulations against their sonic booms.[9]
To appease concerns about the safety and flyability of such a large passenger aircraft, the 747 was designed with multiple structural redundancy, four redundant hydraulic systems, and quadruple main landing gear with 16 wheels which provided a good spread of support on the ground and safety in the event of tire blow-outs. In addition, the 747 had split control surfaces, and sophisticated triple-slotted flaps that minimised landing speeds allowing it to use standard-length runways. The wing was swept back at an unusually high angle of 37.5 degrees which was chosen in order to minimize the wing span, thus allowing the 747 to use existing hangars.[8][10]
In April 1966, Pan Am ordered 25 of the initial 100 series for US$550 million. During the ceremonial 747 contract signing banquet in Seattle, concurrent to Boeing's 50th Anniversary, Juan Trippe predicted the 747 as "...a great Weapon for peace, competing with intercontinental missiles for mankind's destiny.", according to an interview with Malcolm T. Stamper.[11] As launch customer,[1][12] and because of its early involvement before placing a formal order, Pan Am enjoyed unprecedented influence over the design and development of the 747, to an extent not seen by a single airline before or since.[13]
[edit] Production
Boeing did not have a facility large enough to assemble the giant aircraft, so it had to build a new one. The company looked at a number of locations including Walnut Creek, California and Tacoma, Washington. In the end, it decided to build the new plant some 30 miles north of Seattle on a site ajoining a military base at Paine Field near Everett, Washington,[14] which had a 9,500 foot runway. In June 1966, Boeing purchased the 780 acre site.[1]
While developing the 747 had been a major challenge, constructing the plant in which to build it was also a huge undertaking. Boeing president William M. Allen asked Malcolm T. Stamper, then head of the company's turbine division, to lead construction of the Everett factory and start up production of the 747. "How would you like to build an airplane — in fact, the biggest airplane in the world?" Allen asked him in 1966, according to "Legend and Legacy", a Boeing history by Robert Serling.
"Mr. Allen, the only airplane I ever built had rubber bands on it," Stamper said.
"Do you or do you not?" demanded Allen.
"I'd welcome the challenge," Mr. Stamper replied.
In order to level the site, over four million cubic yards of earth had to be moved.[15] Such was the shortage of time that the 747's full-scale mock-up had to be built even before the factory roof had been constructed above it.[16] The plant is the largest building by volume ever built.[6]
Boeing had promised to deliver the 747 to Pan Am by 1970, meaning that it had less than four years to develop, build and test the aircraft. Work progressed at such a breakneck pace that all those who worked on the development of the 747 were given the nickname "The Incredibles".[6] The massive cost of developing the 747 and building the Everett factory meant that Boeing had to borrow, and gambled its very existence on the 747's success; had the project failed, it would have taken the company along with it.[12] However, the gamble paid dividends and Boeing enjoyed a monopoly in the very large passenger aircraft segment until the arrival of the Airbus A380.[17]
[edit] Testing
Before the first 747 was even fully assembled, testing began on numerous components and systems. One of the most anxiously anticipated tests was the emergency evacuation. This entailed seeing how long it took for 560 volunteers to exit from a cabin mock-up using the plane's emergency chutes. The first full-scale test took two and a half minutes instead of the maximum 90 seconds mandated by the Federal Aviation Administration, and resulted in several injuries to the volunteers. Subsequent tests achieved the 90 second limit, albeit at the cost of more injuries. Most problematic was evacuation from the airplane's upper deck: instead of a slide there were an escape harness attached to a reel.[18]
Prior to the 747's first flight, Boeing built an unusual training device known as "Waddell's Wagon" (named after the 747 test pilot, Jack Waddell) which consisted of a mock-up cockpit mounted on the roof of a truck. It was intended to train pilots on how to taxi the plane from the high upper deck position.[6]
On September 30, 1968 the first 747, N7470, was rolled out of the assembly building before the world's press and representatives of the twenty-six airlines that had ordered the plane.[19] Over the following months preparations were made for the first flight which took place successfully on February 9, 1969 with test pilot Jack Waddell at the controls.[20] In spite of a minor problem with one of the flaps, the flight confirmed that the 747 handled extremely well; the plane was found to be largely immune to "dutch roll", a phenomenon that had been a major hazard to the early swept-wing jets.[21]
Later stages of the flight test program revealed some problems: flutter testing showed that the wings suffered oscillation in certain conditions. These difficulties were partly solved by reducing the stiffness of some wing components. However, a particularly severe high-speed flutter problem was only resolved by inserting depleted uranium counterweights as ballast in the outboard engine nacelles of the early 747s.[22] This measure caused some anxiety when several of these aircraft were lost, such as the 1992 crash of El Al Flight 1862 at Amsterdam.[23][24]
The flight test program was considerably hampered by problems with the plane's JT9D engines: these included engine stalls caused by rapid movements of the throttles, and distortion of the turbine casings after a short period of service.[25] The problems caused 747 deliveries to be delayed by several months, resulting in up to 20 planes at one time being left stranded at the Everett plant awaiting engines.[26] The program was further set back when the third of five test aircraft suffered serious damage while attempting to land at Boeing's Renton plant where it was being taken to have its test equipment removed and a cabin installed; pilot Ralph Cokely undershot the short runway and sheared off the aircraft's landing gear.[27] However, these difficulties did not prevent Boeing taking one of the test aircraft to the 28th Paris Air Show in the summer of 1969 where it was displayed to the general public for the first time.
The 747 finally achieved its FAA airworthiness certificate in December 1969, paving the way for the jet's introduction into service.
[edit] In service
On January 15, 1970, First Lady Pat Nixon officially christened a Pan Am Boeing 747 at Washington Dulles International Airport in the presence of Pan Am chairman Najeeb Halaby. Red, white, and blue water was sprayed on the aircraft, rather than breaking a bottle of champagne. The first commercial flight involving the Boeing 747 took place on January 22, 1970 operated by Pan Am between New York's John F. Kennedy International Airport and London Heathrow Airport. Pan Am added 747 service to London from Boston, Washington, and other cities during the spring and summer of 1970. Overnight, a new standard of air travel had been created and other airlines rushed to bring their own 747 jets into service. Trans World Airlines, Japan Airlines, Lufthansa, BOAC, and Northwest Orient would be among the first carriers to offer 747 service on long-haul flights. American Airlines initiated 747 service between New York and Los Angeles by the summer of 1970, and in September 1970 added nonstop 747 flights between Washington and Los Angeles. Soon afterward American Airlines added 747 service from Boston to Chicago and on to Los Angeles. In addition to its foreign destinations, TWA offered 747 flights between San Francisco and New York by early 1971.
Initially, many airlines regarded the 747 with skepticism. McDonnell Douglas and Lockheed were working on wide-body three engine "tri-jets", which were smaller than the proposed 747. Many airlines believed the 747 would prove too large for an average long distance flight, investing instead in tri-jets. There were also concerns that the 747 would not be compatible with existing airport infrastructure—an issue which has resurfaced with the Airbus A380, due to its double-deck feature.[28]
Fuel efficiency was another concern, and this became more critical after the Arab oil crisis which led to economic stagnation in the United States. This lowered the number of airline passengers and made it difficult for airlines to fill their new 747s, so American Airlines replaced coach seats on its 747s with piano bars in an attempt to attract more customers. Eventually, it relegated its 747s to cargo service and then sold them. Continental Airlines also removed its 747s from service after several years. The advent of smaller, more efficient wide bodies, starting with the trijet DC-10 and L-1011 and followed by the twinjet 767 and A300, took away much of the 747's original market, especially as airline deregulation made point-to-point international service more common. Other airlines that have removed 747s from their fleet include Air Canada, Aer Lingus, Avianca, SAS, TAP, America West, and Olympic Airways.
However, many international carriers continued to use the 747 on their busiest routes. The type remained popular among Asian airlines for short and medium-range flights between major cities: in Japan, domestic airlines continue to pack 747s to their maximum passenger capacity. Elsewhere, 747s remain popular on long-range trunk routes, such as transoceanic flights and the Kangaroo routes between Europe and Australia. The largest fleet of 747s today belongs to Japan Airlines, at approximately 78 (series -200s, -300s and 44 -400s). British Airways has the next largest fleet of 747s, comprising 57 747-400s.
[edit] Future of the 747
Since the arrival of the 747-400 in 1989, several stretching schemes for the 747 have been proposed, but the only design to be adopted is 2005's 747-8. The 747-X program was launched in 1996 as Boeing's response to the Airbus A3XX proposal. The 747-X would have consisted of the 747-500X and 747-600X, seating up to 800 passengers and powered by the Engine Alliance GP7200 turbofan developed for the Airbus A380. However, the airlines preferred Boeing to develop an all-new design instead of an updated 747, and the plan was dropped after a few months.
After development of the Airbus A380 formally began in 2000, Boeing reexamined its 747-X studies but instead focused on the Sonic Cruiser,[29] and then on the 787 after the Sonic Cruiser program was put on hold indefinitely.[30] Some of the ideas developed for the 747-X were, however, used on the 747-400ER.
In early 2004, Boeing rolled out tentative plans the 747 Advanced. Similar in nature to the 747-X plans, the stretched 747 Advanced uses advanced technology from the 787 to modernize the design and its systems. On November 14, 2005, Boeing announced it was launching the 747 Advanced as the 747-8.[31] Due to long delays in production of the Airbus A380, two customer signed additional orders,[32][33] two customers cancelled their orders and several launch customers deferred delivery, or considered switching their order to the 747-8 and 777F aircraft.[34][35]
Eventually, the 747 (in all forms) may be replaced by a clean-sheet aircraft dubbed "Y3".
[edit] Variants
There are five major variants of the 747. The 747-100 was the original and launched in 1966. The 747-200 followed soon after with an order in 1968. The 747-300 was launched in 1980, and was followed in 1985 by the 747-400. Lastly, the 747-8 was launched in 2005. Several versions of each variant have been produced, and many of the early variants were in production at the same time, especially in the 1980s.
[edit] 747-100
The first model of the jet, the 747-100, rolled out of the new Everett facility on 2 September 1968. The prototype, named City of Everett, first flew on February 9, 1969,[36] and on January 22, 1970 the 747-100 entered service with launch customer Pan American World Airways on the New York-London route.[37] The flight was supposed to occur on January 21, but engine overheating made the original plane unusable and it had to be substituted, creating a more than 6-hour delay to the next day.[37] The basic -100 has a range of about 4,500 miles (7,242 km) with full load.[38]
The very first 747-100s off the line were built with six (three per side) upper-deck windows to accommodate upstairs lounge areas. A little later, as airlines began to use the upper-deck for premium passenger seating instead of lounge space, Boeing offered a ten window upper deck as an option, and it quickly became the standard. Some -100s were even retrofitted with the new configuration.
With a MTOW of 735,000 lb compared to the 833,000 lb of the 747-200, no freighter model of this aircraft was offered directly by Boeing. However, upon airline retirement, many 747-100s have been converted to freighters over the years. Their cheap acquisition costs more than compensate for lack of carrying capacity. They are also ideal for parcels since volume is paramount to weight. A 747-100 is owned by General Electric and used as a testbed for their engines such as General Electric GEnx.
Total production was 250. Of these, 167 were 747-100, 45 were SP, 29 were SR, and 9 were 100B.
[edit] 747-100B
The 747-100 was later superseded by the 747-100B, which has a stronger airframe and undercarriage design.[38] This increased maximum take-off weight to 750000 lb (340194 kg). The 747-100B was only delivered to Iran Air and Saudia (now Saudi Arabian Airlines).[39]
[edit] 747-100SR
With requests from Japanese airlines, Boeing developed the 747SR as a 'Short Range' variant of the 747-100. The SR has a lower fuel capacity, but can carry more passengers – up to 498 passengers in early versions and more than 550 passengers in later models. The 747SR has a modified body structure to accommodate the added stress accumulated from a greater number of take-offs and landings. Later on, short range versions were developed also of the -100B and the -300. The SR aircraft are primarily used on domestic flights in Japan.[40]
Two 747-100B/SRs were delivered to Japan Airlines (JAL) with a stretched upper deck to accommodate more passengers. This is known as the "SUD" (stretched upper deck) modification.
All Nippon Airways (ANA) operated 747SR on domestic Japanese routes with 455-456 seats but retired the aircraft on 10 March 2006. JAL operates its 747-100B/SR/SUD aircraft with 563 seats on domestic routes and plans for retirement in the third quarter of 2006. JAL and JALways have also been operating the -300SRs on domestic leisure routes and to other parts of Asia. With the arrival of the much more economical Boeing 777-300, the SRs are now being replaced, with just a very few still in operation.
In August 2006 a total of 38 Boeing 747-100 aircraft (all versions) were in airline service with Iran Air (1), Japan Airlines (1), Orient Thai Airlines (2), Saudi Arabian Airlines (7), Evergreen International Airlines (6), Kalitta Air (6), Polar Air Cargo (1) and United Parcel Service (7).[41]
[edit] 747SP
The 747SP was a shortened version of the 747-100. It was introduced into service in 1976 with Pan AM. Apart from the upcoming 747-8 the SP is the only 747 with a modified length fuselage. It was designed to fly higher, faster, and longer than the 747-100. Boeing hoped that the abilities of the SP would compete and take orders from the Douglas DC-10 and create a niche market, however in the end only a total of 45 were built.
As of August 2006 a total of 12 Boeing 747SP aircraft were in airline service with South African Airways (1), Iran Air (2), Iraqi Airways (2), Kinshasa Airways (1), Palace Air (1), Saudi Arabian Airlines (1), Syrian Arab Airlines (2) and Transatlantic International Airlines (2).[41]
[edit] 747-200
Entering service in 1971, and further improved over successive years, the 747-200 had more powerful engines and higher takeoff weights than the -100, allowing it to fly farther. Optional engine models by GE (CF6) and Rolls-Royce (RB211)were offered for the first time. A few early build -200s retained the three window configuration of the -100, but most were built with a ten window per side configuration. As on the -100, a stretched upper deck (SUD) modification was offered much later. KLM remains the only airline to retrofit their -200s with the SUD option. Today, many -200s are still in passenger operation, though in recent years retirement and conversion to freighters has accelerated.
[edit] 747-200B
The 747-200B is an improved version of the 747-200, with increased fuel capacity and more powerful engines. Qantas took delivery of these from 1971. It comes in a combi version as well. The -200B aircraft have a full load range of about 6,700 miles (10,700 km).
[edit] 747-200C
The 747-200C Convertible is essentially a passenger aircraft that can be converted to a freighter and back when needed. The seats are removable and the fuselage has a much bigger door on the maindeck for cargo entry. The -200C could be fitted with a nose door.
[edit] 747-200M
This type can carry both freight and passengers, but unlike the 200C, it can do so at the same time. A wall half way through the main deck, separates the cargo in the back from passengers on the front. This type carries cargo throughout the lower deck, and on half the main deck, along with roughly 200 passengers. Also known as the 747-200 Combi.
[edit] 747-200F
This is a freighter version of the -200 model. It could be fitted with or without the nose door. It has a 105 ton capacity and a MTOW of 833,000 lb. It entered service in 1972 with Lufthansa.
Total production was 393. Of these, 225 were 747-200, 78 were M, 73 were F, 13 were C, and 4 were military. In August 2006 a total of 239 Boeing 747-200 aircraft (all versions) were in airline service. Major operators include: Japan Airlines (13), Nippon Cargo Airlines (10), Air Atlanta Icelandic (15), Air France (9), Atlas Air (16), Kalitta Air (10), Northwest Airlines (28), Cathay Pacific Airways (7) and Southern Air (9). Some 41 other airlines operate smaller numbers of the type.[41]
[edit] 747-300
Following the aborted 747-300 Trijet, Boeing explored increasing the capacity of the 747 by using fuselage plugs to stretch the entire aircraft to seat around 600 passengers, or stretching the upper deck the entire length of the fuselage, however these plans were dropped in favor of a more simple stretch of the upper deck part way along the length of the fuselage.[42] The 747-300 name was revived for this new aircraft, which was introduced in 1980. It was the first 747 model to feature a "stretched upper deck", which was 23 ft 4 inches (7.1 m) longer than earlier variants. The -300 also had a straight staircase for the upper deck rather than the spiral, and this created more room both below and above for more seats. With minor aerodynamic changes, Boeing increased the cruise speed of the -300 to Mach 0.85 from Mach 0.84 on the -100/-200. Also, with improved fuel economy, range improved to 7,700 mi (12,392 km).
Swissair was the launch customer for the 747-300, however, the first plane was delivered to French airline UTA on March 1, 1983.[43] Boeing never launched a 747-300F as it had no operating advantage over the 747-200F. The most significant change between the 747-300 and the 747-200 was the stretched upperdeck which was useless in freighter configuration as no cargo is placed on this deck.
Despite the -300's improvements, only 81 aircraft were ordered, 56 for full passenger use, 21 M and 4 SR. One reason for its limited sales was the imminent launch of the much more advanced 747-400 in 1985 (just two years after the -300 entered service) for which most airlines were prepared to wait. Today, most of the -300 versions are still in passenger operation, mostly in south and west Asia.
[edit] 747-300M
The -300M had similar cargo capacity as the -200M, however with the stretched upperdeck it could carry more passengers. This proved popular in the fleet of KLM on their Africa routes that had few passengers, yet considerable air freight.
[edit] 747-300SR
The Japanese airlines again asked for a high capacity domestic model and Boeing offered the SR. JAL operated such aircraft with over 600 seats on Okinawa-Tokyo route as well as others.
Airlines (at August 2006) operating the Boeing 747-300 include JAL/JALways (12), Saudi Arabian Airlines (9), Pakistan International Airlines (PIA) (6), Qantas (6), and
