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Boeing 747

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File:Pan Am 747 LAX.jpg
Boeing 747 of Pan American World Airways
File:Mkairlines.b747.arp.750pix.jpg
MK Airlines Boeing 747. For more images of the 747 see list at bottom of page

The Boeing 747, also popularly known as the jumbo jet, is the second largest passenger airliner after Airbus A380. Until the first commercial flight of the A380 in 2006, however, it remains the largest aircraft in commercial service. The four-engine 747, produced by Boeing Commercial Airplanes, combines passenger-carrying capacities of up to 600 people with its unique two-deck configuration (the small upper deck is usually used for business-class passengers). A typical mixed-class layout would accommodate about 380 passengers. The characteristic hump created by the upper deck has made the 747 a hugely recognisable icon of air travel. The 747 flies at high-subsonic speeds (typically 0.85 Mach or 565 mph or 909 km/h) and features intercontinental range (8,430 statute miles, or 13,570 km, for the 747-400 version), in some configurations sufficient to fly New York-Hong Kong (roughly a third of the globe) non-stop. By May 2004, a total of 1381 aircraft have been built or ordered in various 747 configurations, making it an extremely profitable product for Boeing.

Historical background

The 747 was born out of the explosion of air travel in the 1960s. The enormous popularity of the Boeing 707 had revolutionised long distance travel, and had began the concept of the "global village" made possible by the jet revolution. Boeing had already developed a study for a very large airplane when it was bidding on a US military contract for a huge airlifter. Boeing lost the contract to Lockheed, but came under pressure from its most loyal airline customer Pan Am to develop a giant passenger plane which would be over twice the size of the 707. In 1966, Boeing had proposed a preliminary configuration for the airliner, which was to be called the 747, and Pan Am got the ball rolling with an order for 25 of the initial -100 series. The original design was a full length double decker. However, following issues with proposed evacuation routes, this idea was 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). Boeing took the shrewd move and designed the 747 so that it could easily be adapted to carry freight, knowing that when sales of the passenger version dried up, it 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", which was initially used as a luxurious first-class lounge/bar area, but as time went on was used for extra seating capacity. In the end however, the supersonic transports such as Boeing's still-born SST and the Concorde never lived up to their promise, being far too expensive to operate profitably at a time when fuel prices were soaring. After being expected to wither on the vine with only 400 sales, 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 cargo derivative has only happened in the early 2000s.

The development of the 747 was a huge undertaking. Boeing did not have a factory big enough to assemble the giant aircraft, so had to build an all-new assembly building near Everett, Washington. This factory is the largest building ever built. Pratt and Whitney developed a massive high-bypass turbofan engine, the JT9D that was, in the beginning, exclusively for the 747. In order to appease concerns about the safety and flyability of such a massive aircraft, the 747 was designed with no less than four backup hydraulic systems, split control surfaces, multiple structural redundancy, and sophisticated flaps which allow it to use standard-length runways.

Initially, Boeing found that the 747 was being treated with skepticism by many airlines. At the time, Boeing's rivals, McDonnell Douglas and Lockheed, were working on wide-body three-engine "tri-jets", which were significantly smaller than the proposed 747. Many airlines wondered if the 747 would prove to be too large for an average long distance flight and instead invested in tri-jets. Furthermore, there was worry about whether or not the 747 would be compatible with existing airport infrastructure.

Another issue raised by the airlines was fuel efficiency. A three-engine airliner burns significantly less fuel per flight than a four-engine, and with airlines trying to lower costs, fuel efficiency was a large issue (this issue would return to haunt Boeing during the 1970s).

Boeing had promised the 747 to Pan Am by 1970, so it had less than four years to develop, build and test the 747. 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 gambled its very existence on the 747's success, and very nearly bankrupted the company in the early 1970s. The gamble paid off however, and Boeing enjoyed a monopoly on very large passenger transports that has only been broken 35 years later with the advent of the Airbus A380.

Variants

747-100

The first edition of the jet, the 747-100, rolled out of the new Everett facility on 2 September 1969. The 747-100 entered service in 1970 with launch customer Pan American World Airways. It was later replaced by the 747-100B, a very similar aircraft with a stronger airframe and undercarriage design. Another -100 variant, the 747-100SR, has a capacity of up to 550 passengers and is used on domestic flights in Japan. The basic -100 has a range of about 4,500 miles with full load.

747-100 aircraft can usually be distinguished by the upper deck, which normally has only three windows. There are exceptions. Also, some airlines purchased "SUD," or "stretched upper deck" modifications, which make the upper deck almost identical to a 747-300.

747-200

Introduced in 1971, and further improved over successive years, the 747-200 has higher thrust and weight-lifting capability than the 747-100, flying farther. It can usually be distinguished by its eight-window upper deck (but, again, some airlines have given their -200 aircraft SUD, and a few early -200s had just 3 windows). The last models of the -200, built in the late 1980s, have a full load range of about 6,700 miles.

The 747-200C and -200F 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 by being converted into freight aircraft, rather than being scrapped.

747SP

The 747SP, or "Special Performance," was first delivered in 1976. The SP was largely a stop-gap model to compete with the Douglas DC-10 and Lockheed L-1011 TriStar. The 747 was simply too big for many routes, and Boeing didn't have a mid-sized widebody to compete in the segment of the market that the DC-10 and TriStar had created. Crippled by the huge costs it had incurred in developing both the 737 and 747 in the late 1960s, Boeing could not afford to develop an all-new design, so instead it shortened the 747 and reoptimised it for speed and range at the expense of capacity. The SP could only accommodate 220 passengers in a 3-class cabin, but could fly over 6,500 miles at speeds of up to 610 mph. Some airline insiders call it the "74 Short" or "Baby Jumbo" because of its shortened fuselage, and stubby appearance.

The 747SP was the longest-flying airliner available until the Airbus A340, and found its way into the fleets of American Airlines, Pan Am, and Qantas, airlines that needed its range for trans-South Pacific routes. (American later used its 747SP's for services to Tokyo.) The 747SP was also used by South African Airways on flights from Johannesburg to London, during the Apartheid years, when 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.

For all its technical achievements, the SP never sold as well as Boeing hoped, only 44 were ever built and most that are still in service are used by operators in the Middle East and Africa.

The SOFIA astronomical observatory is a 747SP modified to carry a 2.5-meter-diameter infrared reflecting telescope.

747-300

The 747-300 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 Japanese domestic (747-300SR) models 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.

747-400

The 747-400 is the latest model of the 747, and also the only series still in production. It added 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. It first entered service in 1989 with Northwest Airlines.

The -400 is available in combi (747-400M) and freighter (747-400F) variants. The Japanese domestic variant, the 747-400D, is the highest-capacity passenger aircraft in the world, capable of carrying 568 passengers.

The 747-400ER is 400's extended range version: it also comes in an all-freight version, the 747-400ERF. Plans to develop a newer model, the 747-400XQLR, which stood for Quiet Long-Range (the X being a designator for an aircraft derivative which is still a design study and has not been officially launched), have evolved into the 747 Advanced.

As yet unnamed, Boeing will convert four passenger 747-400 aircraft into an outsize configuration, in order to ferry 7E7 parts to Everett, Washington for final assembly.

747 Advanced

Boeing is now working with airlines to create a new 747 which will use same engine and cockpit technology as the 7E7 . The new 747 will be quieter, more economical and environmentally friendly. It will be capable of carrying up to 500 passengers in a 3-class configuration and fly over 8,000-nautical-miles ( 14,816 km) at .86 Mach.

Government and military models

The current U.S. Presidential aircraft, VC-25A, is among the most famous 747 models. It is popularly known as Air Force One, even though that name refers to any United States Air Force aircraft carrying the President. VC-25A is based on the civilian Boeing 747-200. Other special 747s include the E-4B airborne emergency command and control post, 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.

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

Powerplants

(For the last versions of each series offered)

Facts & trivia

  • 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.
  • When pressurised, a 747 fuselage holds over a ton of air.
  • The 747-400 is about 25 percent more fuel efficient than the 747-100, and twice as quiet.
  • Early model 747s have more than seven hundred pounds (300 kg) of depleted uranium molded into the engine nacelles. Its purpose is as ballast to prevent the wing from fluttering.
  • One of the original 747 design proposals was a full double decker, similar to the Airbus A380. Boeing dropped the idea at the eleventh hour, arguing that a wide single decker would be both more economical to operate and safer.
  • During the flight certification period, Boeing built a bizarre 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.
  • 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 Douglas DC-10. Boeing was quite keen to discourage the media and the public using the term "jumbo jet" for the 747, but their efforts were in vain, and now the term is synonymous with the 747.
  • 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). The eventual name "Special Performance" was used instead.
  • Due to its immense length, there is a very 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 got air sick. Upon return, the plane went through a shake test for two weeks to sort out the problem and adjust the yaw damper system. This solved the problem and the effect is now too small to be noticeable by passengers.

Disasters

Specific accidents

747 aircraft have been involved in a number of air disasters. However, very few have been due to design flaws in the aircraft itself: most have been because of pilot error, or in a few cases, terrorist action.

Accident summary

  • Hull-loss Accidents: 30 with a total of 2843 fatalities
  • Other occurrences: 6 with a total of 857 fatalities
  • Hijackings: 29 with a total of 22 fatalities

Airlines

Most international airlines use the 747 on their busiest routes. However, as point-to-point international service between midsize cities has become more prevalent, some major airlines have replaced their 747's with smaller and more efficient twinjet aircraft. American Airlines, Continental Airlines, and Delta Air Lines are among the larger carriers to discontinue the 747. Other airlines that have removed the type from their fleet include Aer Lingus, SAS, TAP, and Olympic Airways.

Future development

The 747 is the only Boeing jetliner never to be stretched beyond its original design length. This has been mainly due to the uncertain economics of the commercial airline business, and the lack of suitable engines. Many different stretching schemes for the 747 have been proposed, but none have come to fruition. The 747-X program was launched in 1996, and was intended to be Boeing's response to Airbus' A3XX proposal. The 747-X would have consisted of the 747-500X and 747-600X which would have provided seating for 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.

When the Airbus A380 was formally launched in 2000, Boeing dusted off its 747-X studies in a bid to thwart sales of the Airbus competitor. But once again airlines weren't interested, and Boeing cancelled the program in 2001 after no orders were forthcoming, and devoted its energies to the ill-fated Sonic Cruiser. Some of the ideas developed for the 747-X did however make it into production in the 747-400ER.

The long-term future of the 747 is now in doubt—its dominance on long-haul routes has been progressively eroded in recent years by the new generation of ETOPS-compatible twinjets such as the Airbus A300 and Boeing's own 767 and 777. Despite Boeing's claims that the A380 can never be profitable, Airbus have already sold over 120 of the giant aircraft. Previously loyal 747 customers such as Qantas, Virgin Atlantic and Singapore Airlines have all ordered the A380, and sales of the passenger 747 have dwindled to almost nothing—the vast majority of 747s made now are freighters. Boeing has promised that it will always be ready to produce larger, more advanced versions of the 747 when the market for such a plane develops, but industry analysts are already predicting the end for the 35-year old giant.

Nonetheless, in early 2004, Boeing rolled out tentative plans for what it calls the 747-Advanced. As the first A380 prototypes edged ever closer to their first flight, this was clearly evidence that the company was still prepared to mount a challenge to Airbus. Essentially another "recycle" of 747-X plan, the stretched 747A intends to use technology from the 7E7 Dreamliner to bring the 747 into the new millennium. Time will tell, if Boeing manages to get this "paper airplane" into production.

List of 747 images


Related content
Related Development

Boeing E-4 - Boeing VC-25 - Shuttle Carrier Aircraft

Similar Aircraft

Airbus A340 - Airbus A380 - Ilyushin Il-96

Designation Series

707 - 717 - 727 - 737 - 747 - 757 - 767 - 777 - 7E7 - 747A

Related Lists

List of airliners - List of civil aircraft

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