Boeing 747

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The Boeing 747, commonly called the Jumbo Jet, is one of the most recognizable modern jet airliners and is the largest airliner currently in airline service. First flown commercially in 1970, it held the size record for more than 35 years, although it has been surpassed by the Airbus A380 (due to enter service in late 2006). The Soviet-built Antonov An-225, a transport, remains the world's largest aircraft in service, while the Hughes H-4 Hercules had a larger wing-span.["Ask Us - Largest Plane in the World"], [Aerospaceweb.org], retrieved April 29 2006

The four-engine 747, produced by Boeing Commercial Aircraft, uses a two-deck configuration. 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. By February 2006, a total of 1430 aircraft have been built or ordered in various 747 configurations, making it a very profitable product for Boeing. ["Model 747"], [Orders and Deliveries], The Boeing Company, retrieved April 29 2006.

The 747-400, the only series currently in production, flies at high-subsonic speeds (typically mach (}} km/h)) and features intercontinental range ( nm (}} km)).["Technical Characteristics -- Boeing 747-400"], Boeing Commercial Aircraft, retrieved April 29 2006 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 11185 miles ( kilometres) in 20 hours and 9 minutes, although this was a delivery flight with no passengers or freight aboard.["Boeing aircraft Take Qantas Further"], Qantas, retrieved April 29 2006

Contents

History

Development

The prototype 747, City of Everett, at the Museum of Flight in Seattle, Washington.

The 747 was born from the explosion of air travel in the 1960s. The era of commercial jet transportation, led by the enormous popularity of the Boeing 707, had revolutionized long distance travel and made possible the concept of the "global village." Boeing had already developed a study for a very large airplane while bidding on a US military contract for a huge airlifter.[History - "747 Commercial Transport"], The Boeing Company, April 29 2006 Boeing lost the contract to Lockheed's C-5 Galaxy but came under pressure from its most loyal airline customer, Pan Am, to develop a giant passenger plane that would be over twice the size of the 707. In 1966 Boeing proposed a preliminary configuration for the airliner, to be called the 747. Pan Am ordered 25 of the initial 100 series for US$550 million, becoming its launch customer.["Passenger Planes: Boeing 747"], David Noland, Infoplease (Pearson Education), retrieved April 30 2006 The original design was a full-length double-decker fuselage. Issues with evacuation routes caused this idea to be scrapped in favor of a wide-body design.["The Boeing 747"], Judy Rumerman, U.S. Centennial of Flight Commission, retrieved April 30 2006

At the time, it was widely thought that the 747 would be replaced in the future with an SST (supersonic transport) design. In a shrewd move, Boeing designed the 747 so that it could easily be adapted to carry freight. Boeing knew that if and when sales of the passenger version dried up (see below regarding the future sales of the 747), the plane could remain in production as a cargo aircraft. The cockpit was moved to a shortened upper deck so that a nose cone loading door could be included, thus creating the 747's distinctive "bulge". The supersonic transports, including the Concorde and Boeing's never-produced 2707, never lived up to expectations, such planes being too expensive to operate profitably at a time when fuel prices were soaring, and also there were difficulties of operating such aircraft due to regulations regarding flying supersonic over land.["The Concorde Supersonic Transport"], T.A. Heppenheimer, U.S. Centennial of Flight Commission, retrieved April 30 2006

Cargolux Boeing 747-400F with the nose cone loading door open.

The 747 was expected to become obsolete after sales of 400 units. But the 747 outlived many of its critics and production passed the 1,000 mark in 1993. The expected slow-down in sales of the passenger version in favour of the freighter model has only been realized in the early 2000s, around 2 decades later than expected. The development of the 747 was a huge undertaking - Boeing did not have a facility large enough to assemble the giant aircraft, so the company built an all-new assembly building near Everett, Washington. The factory is the largest building by volume ever built, over 780 acres of land.

Pratt and Whitney developed a massive high-bypass turbofan engine, the JT9D, which was initially used exclusively with the 747. To appease concerns about the safety and flyability of such a massive aircraft, the 747 was designed with four backup hydraulic systems, split control surfaces, redundant main landing gear, multiple structural redundancy, and sophisticated flaps that allowed it to use standard-length runways. The wing was swept back at an unusually high angle of 37.5 degrees, and it was chosen in order to minimize the wing span, thus allowing the 747 to use existing hangars.Bowers, p 508

During the flight certification period, 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 aircraft from the high upper deck position.

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 airplane. Work progressed at such a breakneck pace that all those who worked on the development of the 747 were given the nickname "The Incredibles". 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. Initial problems with the JT9D's development forced Boeing to delay deliveries up to year, and as a result up to 30 planes at one time were left stranded at the Everett plant, with the company on the brink of bankruptcy.

The gamble paid dividends, however, and Boeing enjoyed a monopoly in the very large passenger aircraft industry for decades. In fact, the record and benchmark set by the 747 would only be surpassed, more than 35 years after its first delivery, by the Airbus A380, built by Boeing's rival.["Airbus unveils 'superjumbo' jet"], BBC News, January 18 2005

In service

Flight cockpit of the Boeing 747-200.

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 21 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. TWA, 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.

Initially, many airlines regarded the 747 with skepticism. McDonnell Douglas (which merged with Boeing) and Lockheed, were working on wide-body three-engine "tri-jets", which were significantly 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, similar concerns that the Airbus A380 currently faces, however compounded even more due to its double-decker feature.["How the Airbus A380 Works - Triumph or Mistake?"], Howstuffworks, retrieved April 29 2006

Another issue raised by the airlines was fuel efficiency. A three-engine airliner generally burns less fuel per flight than a four-engine, and with airlines trying to lower costs, fuel efficiency was an important issue that would briefly return to haunt Boeing in the 1970s.

Many of the airlines' fears came to bear in the 1970s. The Arab oil crisis and economic stagnation in the United States lowered the number of airline passengers and made it difficult for airlines to fill their new 747s. 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 widebodies, 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 airlines 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 Oceania. 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 56 747-400s.

United Airlines Boeing 747-400 parked at Denver International Airport.

Future of the 747

Many different 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. General Electric and P&W formed the Engine Alliance and designed the GP7200 turbofan to power the stretched 747. Airlines, however, would have 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 was formally begun in 2000, Boeing reexamined its 747-X studies but instead devoted its energies to the Sonic Cruiser["Boeing Shelves 747X to Focus on Faster Jet"], People's Daily, March 30 2001, and then later on the 787 after the Sonic Cruiser program was put on hold for an undefined period.["Boeing's Amazing Sonic Cruiser It was supposed to change the way the world flies. Instead the world changed."], Alex Taylor III, Fortune, December 9 2002 Some of the ideas developed for the 747-X were, however, used in the production of the 747-400ER.

In early 2004, Boeing rolled out tentative plans for what it called 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. ["Boeing Launches New 747-8 Family"], The Boeing Company press release, November 14 2005 Eventually, the 747 (in all forms) will be replaced by a clean-sheet aircraft dubbed "Y3".

Variants

Boeing 747-100 in livery of launch customer Pan Am

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["Boeing 747 takes maiden flight on February 9, 1969"], HistoryLink, retrieved 30 April 2006, and on January 1 1970 the 747-100 entered service with launch customer Pan American World Airways. It was later superseded by the 747-100B, which has a stronger airframe and undercarriage design.Wilson, p. 54 The basic 100 has a range of about mi (}} km) with full load. The US military designation for 747-100 is C-19.

The very first 747-100s off the line were built with three 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.

Some 747-100 aircraft were converted into freighters and designated 747-100F.Bowers, p 515 A total of 205 units were built, including 10 -100B and 29 -100SR variants.

747SR

Boeing developed the 747SR as a 'Short Range' variant of the -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. Bowers, p 516-517

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.

One ex-JAL 747SR-46, registered N911NA, is currently being operated by NASA as a Shuttle Carrier Aircraft. (It joined an ex-American Airlines 747-123 in 1988 due to a recommendation from the Challenger inquiry board to have two SCAs, and the aircraft first carried a shuttle in 1991.)

747-200

Air France Boeing 747-200 in landing configuration.

Introduced 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 further. A few early build -200s retained the three window configuration of the -100, but most were built with a ten window configuration. As on the -100, a stretched upper deck modification was offered much later. KLM remains the only airline to retrofit their -200s with the SUD option. The last models of the 200, the 200B, built in the late 1980s, have a full load range of about mi (}} km). The US military designation for 747-200B is C-25. The USAF only operates two C-25, in VIP configuration (VC-25A). These two aircraft, tail numbers 28000 and 29000 are better known as Air Force One when the President of the United States is onboard.

The 747-200C Convertible and 747-200F Freighter variants were designed to carry air freight. The 747-200F is a pure freighter, while the 747-200C is a "convertible" aircraft that can carry either passengers or freight. A sub-variant is unofficially called the 747-200M and is a "combi" aircraft that can carry both at the same time. Like the 100, many 200s have been given a new lease on life as freight aircraft.

The 747-200B is an improved version of the 747-200, with increased fuel capacity and more powerful engines. It comes in a combi version as well.

[Seat diagrams for 747-200]

747SP

Boeing 747SP refitted as the SOFIA astronomical observatory

The 747SP, or "Special Performance," was first delivered in 1976. The SP was developed to target two market requirements. The first was to offer a smaller model to compete with the McDonnell Douglas DC-10 and Lockheed L-1011, while maintaining commonality with the larger standard 747s. The 747 was simply too big for many routes, and Boeing did not have a mid-sized widebody to compete in the segment of the market that the DC-10 and L-1011 had created. The second market requirement was the ultra long-range routes which were emerging in the mid-1970s. This required not only a longer range, but a higher cruising speed. Boeing could not afford to develop an all-new design, so instead shortened the 747 and re-optimized it for speed and range at the expense of capacity.

Apart from having a shorter fuselage, the 747SP differs from other 747 variants in having a larger tail surface and simpler wing flap system. The 747SP uses larger single-piece flaps on the trailing edges (other 747s use triple flaps). The SP could typically only accommodate 220 passengers in a 3-class cabin, but could fly over mi (}} km) at speeds of up to mph (}} km/h). Some airline insiders call it the "74 Short" or "Baby Jumbo" because of its shortened fuselage, and stubby appearance. Originally designated 747SB (standing for Short Body), Boeing later changed the production designation to 747SP, reflecting the aircraft's longer range and faster cruise speed.

The 747SP was the longest-range airliner available until the 747-400 entered service in 1989. For all its technical achievements, the SP never sold as well as Boeing hoped. Only 45 were ever built and most that are still in service are used by operators in the Middle East. One special 747SP is the SOFIA astronomical observatory, where the airframe was modified to carry a 2.5-meter-diameter infrared reflecting telescope to high-altitude, the limit to which infrared penetrates the atmosphere. Originally delivered to Pan Am and titled "Clipper Lindbergh", NASA has displayed the name in Pan Am script on the plane.

Past 747SP operators include:

Pan Am took delivery of ten 747-SP21 aircraft between 1975 and 1979, operating them on trans-Pacific routes to Asia and Oceania. The aircraft and routes were sold to United Airlines in 1986, and remained in operation until 1994.
South African Airways operated six 747-SP44 aircraft on flights from Johannesburg to London, during the Apartheid years, when that airline's aircraft were not allowed to fly over African countries and had to fly around the Bulge of Africa. The extra range allowed aircraft to cover the additional distance.
TWA operated three 747-SP31 aircraft from 1979 to 1986. Two of these were purchased by American Airlines and used on London and Tokyo routes until 1993.
Iran Air took delivery of four 747-SP86 aircraft between 1976 and 1978. Prior to the 1979 Islamic revolution, the aircraft were used on the daily Tehran-New York flight, at the time the longest non-stop airline route in the world.
Qantas operated two 747-SP38 aircraft from 1980 to 2004.

The 747SP was originally intended to be known as the 747SB (the SB logically standing for "Short Body", before it was nicknamed "Sutter's Balloon" by Boeing employees, being named after 747 chief engineer Joe Sutter). Eventually the name "Special Performance" was used instead.

747-300

Pakistan International (PIA) Boeing 747-300 on final approach to London Heathrow Airport

The first incarnation of the 747-300 would have been a trijet version of the 747SP, intended to compete with the DC-10 and L-1011 TriStar. This plan was scrapped due to insufficient demand.

The 747-300 name was revived for a new aircraft, which was introduced in 1980, and was the first 747 model to feature a "stretched upper deck," which increased its capacity over earlier models. Combi (747-300M) and short range (747-300SR) models (mainly for Japanese domestic routes) were also built. The upper deck was now accessed via a straight staircase, rather than the spiral steps that featured in the 100 and 200. The maximum range of a 747-300 is mi (}} km).

Airlines currently operating a large number of this type are JAL/JALways, Air India, Saudi Arabian Airlines, Pakistan International Airlines (PIA), Qantas, and Thai Airways.

[Seat diagrams for 747-338 subvariant]

747-400

British Airways Boeing 747-400 landing at London Heathrow Airport.

The 747-400 is the latest model of the 747 and the only series in production. It added ft (}} m) wing tip extensions and ft (}} m) winglets, an all-new glass cockpit which dispensed with the need for a flight engineer, tail fuel tanks, revised engines, an all-new interior, and newer in-flight entertainment to the basic design of the -300 series. The passenger version first entered service in February 1989 with Northwest Airlines. The combi version entered service in September 1989 with KLM. The freighter version entered service in November 1993 with Cargolux.

The 747-400 is about 25% more fuel efficient than the 747-100, and twice as quiet. It is available in all passenger, combi (747-400M) and freighter (747-400F) variants. A new sub-variant, the 747-400BCF (Boeing Converted Freighter) entered service on 19 December 2005 with Cathay Pacific Cargo, operating its first flight from Hong Kong International Airport to Penang's Bayan Lepas International Airport on 21 December 2005. These are ex passenger variants of the -400 converted into freighter form by Boeing. Until the Airbus A380 officially enters service, the Japanese domestic variant, the 747-400D, is potentially the highest-capacity passenger aircraft in the world: ANA used to operate a few of its 747-400Ds in an all-economy 594-seat configuration. However, since the two Japanese operators JAL and ANA have fitted the aircraft with bigger business class areas, the highest number of seats at the moment on a passenger airplane is 587 on 747-400 aircraft operated by the French airline Corsairfly. The -400D lacks the wing tip extensions and winglets included on other variants, allowing for increased number of takeoffs and landings by lowering wing stresses. The weight saved from the lack of winglets also means lower fuel burn, which suits the short-haul Japanese domestic market where the aerodynamic advantages of winglets do not come into effect. The -400D can be converted to the normal longer range -400 version when needed.

The US military designation for 747-400 is C-33, intended to augment the C-17 fleet, but the plan was cancelled in favor of purchasing additional C-17 military transports.

The 747-400ER is 400's extended range version: it also comes in an all-freight version, the 747-400ERF.

[Seat diagrams for 747-400]

Boeing 747 Large Cargo Freighter

747 Large Cargo Freighter

Boeing announced in October 2003 that due to the high cost of marine shipping, air transport will be the primary method of transporting parts for the 787. Passenger 747-400 aircraft are to be converted into an outsize configuration, in order to ferry sub-assemblies to Everett, Washington for final assembly. It has a bulging fuselage like the Super Guppy or Airbus Beluga cargo planes used for transporting wings and fuselage sections. The Large Cargo Freighter can hold three times the volume of a 747-400F freighter. (See: Boeing news releases [link], [link], [link]). The conversion, designed by Boeing´s Moscow office, is to be carried out in Taiwan by a subsidiary of the Evergreen Group. Boeing has purchased two former China Airlines aircraft which are currently being modified and a third aircraft, yet to be acquired, will be added later.

Delivery times for the wings — built in Japan — will be reduced from around 30 days to one day with the 747 LCF. Evergreen International Airlines, which is unrelated to the Evergreen Group, will be the operator of the LCF fleet.

747-8

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Boeing announced a new 747 model, the 747-8 (referred to as the 747 Advanced prior to launch) on November 14 2005, which will use same engine and cockpit technology as the 787 (It was decided to call it the 747-8 because of the technology it will share with the 787 Dreamliner). Boeing claims that the new design will be quieter, more economical and more environmentally friendly. The passenger version (dubbed 747-8 Intercontinental) will be capable of carrying up to 450 passengers in a 3-class configuration and fly over nm (}} km) at mach (}} km/h). As a derivative of the already common 747-400, the 747-8 has the economic benefit of similar training and interchangeable parts.

According to [Bloomberg], Boeing is staking its position as the dominant maker of the biggest passenger planes on selling Pakistan International Airlines Corp. and other Asian carriers the first of a longer, more fuel-efficient version of its 747-8 model.

Since 1990, the U.S. presidental fleet consists of two highly-customized Boeing 747-200Bs.

Government and military

The current U.S. presidential aircraft, two 747's tail numbered 28000 and 29000 with Air Force designation VC-25A, are among the most famous 747 models. They are popularly known as Air Force One, although that name technically refers to any United States Air Force aircraft carrying the President. Both VC-25A's are based on the civilian 747-200B, though they contain many of the innovations introduced on the 747-400 (such as an updated flight deck and engines.) Other special 747s include the E-4B Formerly known as National Emergency Airborne Command Post (referred to colloquially as "Kneecap"), now referred to as National Airborne Operational Command (NAOC), modified 747s to transport the Space Shuttle (Shuttle Carrier Aircraft), and aerial refueling tankers. A recent addition to the military's 747 arsenal is the experimental Airborne Laser, a component of the National Missile Defense plan. T/Space is also planning to use a 747 for its CXV space capsule proposal.

A number of other governments also use the 747 as a VIP transport, including Bahrain, Brunei, India, Iran, Japan, Oman, Qatar, Saudi Arabia, and United Arab Emirates.

Powerplants

A PIA B747 taking off from Allama Iqbal Intl Airport, Lahore

(For the last versions of each series offered)

747-100
*four Pratt & Whitney JT9D-7A turbofans or
*four General Electric CF6-45A2 turbofans or
*four Rolls-Royce RB211-524B2 turbofans

747-200/300
*four Pratt & Whitney JT9D-7R4G2 turbofans or
*four Rolls-Royce RB211-524D4 turbofans or
*four General Electric CF6-50E2 turbofans
747-400
*four Pratt & Whitney PW4062 turbofans or
*four Rolls-Royce RB211-524H turbofans or
*four General Electric CF6-80C2B5F turbofans
747-400ER
*four Pratt & Whitney PW4062 turbofans or
*four General Electric CF6-80C2B5F turbofans
747-8
* four General Electric GEnx turbofans

Technical data

Measurement	747-100 (initial version)	747-400ER (current version)	747-8 Intercontinental (future version)[link]
Length	70.7 m	70.7 m	74.2 m
Span	59.6 m	64.4 m	68.5 m
Height	19.3 m	19.4 m	19.4 m
Wing area	511 m²	541 m²	?
Weight empty	162.4 t	180.8 t	?
Maximum take-off weight	340.2 t	412.8 t	435.4 t
Cruising speed	mach (}} km/h)	mach (}} km/h)	mach (}} km/h)
Maximum speed	mach (}} km/h)	mach (}} km/h)	mach (}} km/h)
Range fully loaded	9,040 km	14 200 km	15 372 km
Max. fuel capacity	183 380 litres	241 140 litres	227 600 litres
Max. fuel/Range, fully loaded	20.3 L/km	17.0 L/km	14.8 L/km
Cargo capacity	170.6 CBM (5 pallets + 14 LD1s)	158.6 CBM (4 pallets + 14 LD1s)	275.6 CBM (8 pallets + 16 LD1s)
Engines (example)	4 × Pratt & Whitney JT9D, 209 kN thrust each	4 × General Electric CF6-80, 274 kN thrust each	4 × General Electric GEnx-2B67, 296 kN thrust each
Cockpit Crew	Three	Two	Two

Facts & trivia

The seating chart for a standard 747 found in most airlines.

A 747-400 has six million parts (half of which are fasteners) made in 33 different countries.
Just one engine on a 747 produces more thrust than all four engines on an early model Boeing 707 combined.
As with other airliners such as the DC-10, the engines on a 747 are not visible from the cockpit windows. This configuration has had significance during various accidents and incidents involving this aircraft.
When pressurized, a 747 fuselage holds over a ton of air.
Early model 747s have more than 700 lb (300 kg) of depleted uranium molded into the engine nacelles. Its purpose is as ballast to prevent the wing from fluttering.
At the time of its launch, the term "jumbo jet" had already been coined by the media to describe a general class of new wide-bodied airliners then being developed, including the Lockheed L-1011 TriStar and McDonnell Douglas DC-10. Boeing was keen to discourage the media and the public from using the term "jumbo jet" for the 747, but their efforts were in vain and now the term is synonymous with the 747.
Due to its length, there is a small flexure of the fuselage in flight. This effect was not anticipated in the design of the autopilot on early models, and so there is a very slow oscillation in yaw when flying on autopilot. This was first discovered on an overseas flight to the Paris Airshow, when some of the people in the rear became air sick. Upon return, the plane went through tests to solve the problem and adjust the yaw damper system. The effect is now too small to be noticeable by passengers.
To enable easy transportation of spare engines between sites by airlines, early 747s include the ability to attach a non functioning fifth-pod engine under the port wing of the aircraft, between the nearest functioning engine and the fuselage. Photographs of planes flying in this configuration are highly prized by aircraft enthusiasts. [link] [link][link]
There are other aircraft with prominent humps on the upper fuselage including the Carvair, which was built from 1961 to 1969. Its most notable appearance is in the 1964 James Bond movie Goldfinger.
Although the upper deck might seem small compared to the size of the whole aircraft, it can seat a significant number of people: JAL has 86 seats on the upper deck of its B747-400D aircraft.
The 747 is certified to fly on 3 of its 4 engines. A 747 can successfully take-off even if an engine fails after rotation, and in many cases the flight can continue to its destination.
On 24 May 1991 an El Al Boeing 747 airlifted a record-breaking 1,087 passengers - Ethiopian Jews flying from Addis Ababa to Israel as part of Operation Solomon.

Preserved aircraft

As increasing numbers of 'classic' 747-100 and 747-200 series are retired, some are finding their way into aircraft museums. They include:

Boeing 747-100 [N7470], "City of Everett", the first 747 prototype Museum of Flight, Seattle, Washington, USA
KLM 747-200(SUD) PH-BUK "Louis Blériot" at National Aviation Theme Park Aviodrome, Lelystad, Netherlands
Qantas 747-200 VH-EBQ "City of Bunbury" at Qantas Founders Outback Museum, Longreach Airport, Longreach, Queensland, Australia
South African Airways 747-200 ZS-SAN "Lebombo" and 747SP ZS-SPC "Maluti" at Rand Airport, Johannesburg, South Africa
Lufthansa 747-200 D-ABYM "Schleswig-Holstein" at Technik Museum Speyer, Speyer, Germany
Air France 747-100 F-BPVJ at Musée de l'Air et de l'Espace, Le Bourget airport, Paris, France
Iran Air 747SPs EP-IAA and EP-IAC and 747-200F EP-ICC at Tehran Aerospace Exhibition, Tehran, Iran

Disasters & Incidents

The Tenerife disaster, a collision between two 747s in heavy fog, remains the single worst accident in aviation history.

The Tenerife disaster on March 27 1977 claimed a total of 583 lives when two 747s collided in heavy fog at Los Rodeos Airport, making it the highest death toll of any accident in aviation history.["1977: Hundreds dead in Tenerife plane crash"], BBC News On This Day, retrieved May 26 2006 On August 12 1985, the Japan Airlines Flight 123 (a 747SR) lost control and crashed, causing 520 fatalities and is currently the worst single-aircraft disaster in aviation history.[Japan marks air crash anniversary], BBC News, August 12 2005 The Lockerbie bombing, the deadliest terrorist attack against the United States until the September 11, 2001 attacks, was a Pan-Am 747-100.

Despite all these, very few crashes have been attributed to design flaws of the 747: The Tenerife disaster was a result of pilot error, ATC error and communications failure, while Japan Airlines Flight 123 the consquence of improper aircraft maintenance. United Airlines Flight 811, which suffered an explosive decompression mid-flight on February 24 1989, subsequently had NTSB issuing a recommendation to have all similar 747-100 cargo doors modified. TWA Flight 800, a 747-100 that exploded mid-air on July 17 1996, led to the Federal Aviation Administration proposing a rule requiring the installation of an inerting system in the center fuel tank for most large aircraft. As of May 2006, there were a total of 44 hull-loss occurrences involving 747s, with 3707 fatalities.

References

A size comparison between four of the largest aircraft, in wingspan and length.

Peter M Bowers, (1989), Putnam Aeronautical Books, Boeing aircraft since 1916. ISBN 0851778046
Stewart Wilson, (1999), Aerospace Publications Pty Ltd, Airliners of the World. ISBN 1875671447