Overview

The Boeing 747, commonly called a Jumbo Jet, is among the most recognizable jet airliners and is the largest passenger airliner in service. First flown commercially in 1970, it has held the passenger capacity record for more than 35 years.

The four-engine 747, produced by Boeing's Commercial Airplane division, 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. As of November 2006, 1469 planes have been built with 89 more on order in various 747 configurations,[2] making it a very profitable product for Boeing.

The 747-400, the only series in production, 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. The Soviet-built Antonov An-225 cargo transport remains the world's largest aircraft in service, while the Hughes H-4 Hercules had a larger wing-span.

History

The 747 was a monumental engineering and management challenge. In 1966, with the company's future riding on the success of the 747, Boeing president William M. Allen asked Malcolm T. Stamper, then head of the company's turbine division, to lead its development. "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.

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 fixed-wing aircraft while bidding on a US military contract for a huge cargo plane.[6] 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.[1][7] 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.

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 transport. 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, were not widely adopted, such planes being difficult 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.[9]

The 747 was expected to become obsolete after sales of 400 units. But the 747 outlived many of its critics' expectations 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 two 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,[6] on over 780 acres of land.[1]

Pratt and Whitney developed a massive high-bypass turbofan engine, the JT9D, which was initially used exclusively with the 747. Four of these engines mounted in pods below the wings power 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.

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 plane from the high upper deck position.[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.[7] 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.[8]

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 A380, built by Boeing's rival, Airbus.

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 Airbus A380. This engine was rumored to also have been planned to power the 747-X. 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 formally began in 2000, Boeing reexamined its 747-X studies but instead devoted its energies to the Sonic Cruiser,[13] and then later on the 787 after the Sonic Cruiser program was put on hold for an undefined period.[14] 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.[15] Eventually, the 747 (in all forms) may be replaced by a clean-sheet aircraft dubbed "Y3".

Trivia

A 747-400 has six million parts (half of which are fasteners) made in 33 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.

Because of 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.[4][5][6]

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 747-400D 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. The passenger count became 1,088 when a baby was born in-flight.

In December 2004, a special Boeing 747-400 (B-18210) was delivered to China Airlines. It is nicknamed "747 Dreamliner". Its livery is a combination of Boeing's corporate livery on the fuselage and China Airlines's plum blossom on the tail. It is one of two non-retrofitted non-747-400ERs to feature Boeing's Signature Interior from the Boeing 777 (the other being B-18211, also delivered to China Airlines). These were the last 747-400s to be produced and delivered in a passenger configuration.[citation needed]

There are other aircraft with prominent humps on the upper fuselage including the Carvair, which was built from 1961 to 1969, which appeared in the 1964 James Bond movie Goldfinger.

The 747 has appeared as a setting for a number of films. The most well known of these is the Airport series of disaster films. Airport 1975 centers around a midair collision between a 747 and a small aircraft, which kills the flight crew, leaving the stewardess to land the plane. The 747 used was an American Airlines 747-123, which was leased by Universal Studios for the production at a cost of $30,000 per day of flight. The "American Airlines" logos on the plane were removed, and replaced with those of the fictional "Columbia Airlines." The next film in the series, Airport '77, features a 747-100 converted into a luxury private aircraft, which is hijacked by thieves on its inaugural flight, and inadvertently crashes and sinks intact into 120 feet of water near Bermuda, trapping the passengers (and thieves) inside. The 747 in the film is a combination of recycled footage from Airport 1975 and a highly detailed miniature. Other films using a 747 include Snakes on a Plane, Air Force One, Turbulence and Executive Decision. The film in the james bond series "Casino Royale" (2006) featured a fictional aircraft called "Skyfleet" It resembles a 747 having used an old 747 without engines. The nose was reshaped, two tandem mock engines were placed inboard, and a fake fuel tank pod where the outboard 747 engines are located. The film has a blooper where, in some scenes, the aircraft has non-standard 747 winglets which are missing in other scenes.

Among the seven largest U.S. passenger airlines, American, United, Delta, Continental, Northwest, Southwest, and US Airways, only United and Northwest (as of 2006) have 747s in service.