The Boeing 747 is a wide-body commercial airliner and cargo transport aircraft, often referred to by its original nickname, Jumbo Jet, or Queen of the Skies. It is among the world's most recognizable aircraft,and was the first wide-body 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,[8] but it exceeded its critics' expectations with production passing the 1,000 mark in 1993.By September 2012, 1,448 aircraft had been built, with 81 of the 747-8 variants remaining on order.
The 747-400, the most common passenger version in service, is among the fastest airliners in service with a high-subsonic cruise speed of Mach 0.85–0.855 (up to 570 mph, 920 km/h). It has an intercontinental range of 7,260 nautical miles (8,350 mi or 13,450 km).[10] The 747-400 passenger version can accommodate 416 passengers in a typical three-class layout, 524 passengers in a typical two-class layout, or 660 passengers in a high density one-class configuration. The newest version of the aircraft, the 747-8, is in production and received certification in 2011.
Deliveries of the 747-8F freighter version to launch customer Cargolux began in October 2011; deliveries of the 747-8I passenger version to Lufthansa began in May 2012. The 747 is to be replaced by the Boeing Y3 (part of the Boeing Yellowstone Project) in the future.
Boeing 747 classics
The mid-1960s saw the development and introduction of many new jetliners. None, however, has matched the dramatic impact of the 747. Increasingly crowded skies and the availability of large-thrust engines added to the incentive for creating the giant 747. It all began with the 747-100, the first in the 747 Classics series, which also includes the-200 and -300 models.
747-100 - The World's First Jumbo Jet
The 747-100 entered commercial service in 1970. Initially, engines only were available from Pratt & Whitney, but by 1975 engines also were available from General Electric and Rolls-Royce. Boeing delivered 250 of the 747-100s, the last in 1986. Boeing built two versions of the 747-100 passenger airplane, one of which had a higher payload capacity and was known as the -100B. The
747-100 also was available as a short-range airplane, which had a modified body structure to accommodate a greater number of takeoffs and landings. This model typically was used by airlines on short flights with a high-passenger capacity, as many as 550. Boeing also built the 747-100SP (special performance), which had a shortened fuselage and was designed to fly higher, faster and farther non-stop than any 747 model of its time.
747-200 - Continuing the Legacy
Although the 747-200 was developed after the 747-100, it was built during roughly the same time frame. The first -200 went into commercial service in 1971, and Boeing delivered a total of 393, the last in 1991. Although its external appearance is nearly identical to the 747-100, it was designed to carry more payload. In addition to being offered as a passenger airplane, the -200 was the first 747 to be configured as a freighter, a combination passenger-freighter and a convertible.
From the beginning, the 747 was designed to serve as an all-cargo transport. The first 747 Freighter could easily carry 100 tons (90,000 kg) across the Atlantic Ocean or across the United States. Its operating cost was 35 percent less per ton mile than the 707 Freighter. The 747 Freighter has a hinged nose to allow cargo loading through front of the airplane, with the option of a large side-cargo door.
The 747-200 Convertible was configured to serve as a passenger airplane, a freighter or a combination of both. This airplane responded to airlines' needs to carry different payloads at different times of the years, such as higher passenger capacities during the summer and more cargo during the winter. Similar to the convertible is the -200 Combi, which was designed to serve as a passenger-only airplane or as a passenger-freighter mix.
The combi has a large side-cargo door on the main deck, and is used by airlines to make better use of their routes during different times of the year. The convertible has a nose cargo door similar to the freighter.
747-300 - Moving Forward With Significant Changes
The 747-300 entered commercial service in 1983, and was the first to integrate the most significant changes of the 747 Classics. These changes included an extended upper deck and improved engines with a reduced fuel burn of 25 percent per passenger. In addition, passenger capacity increased 10 percent by extending the upper deck and relocating the new straight stairway to the rear of the upper deck (prior models had a spiral-shaped staircase in the center of the upper deck). Boeing delivered 81 747-300s in passenger, combi and short-range configurations, the last in 1990.
747 Classics With Special Assignments
Boeing has designed or modified 15 747s for special purposes. Among them are two 747-200s delivered as U.S. presidential Air Force One airplanes, and four 747-200s, designated E-4s, delivered to the U.S. Air Force as airborne emergency command and control posts. Another 747 was modified to ferry the U.S. space shuttle between California and Florida. Other 747s have been demonstrated as tankers capable of refueling other airplanes in flight.
In addition, Boeing completed modifications to 19 existing 747-100s to Civil Reserve Air Fleet (CRAF) configurations in 1990. If called into service by the U.S. Air Force, these passenger planes can be converted to freighters in less than 48 hours. Boeing donated the original 747, line No. 1, to Seattle's Museum of Flight. On lease to Boeing, it occasionally is used as a flying testbed for aeronautical developments.
Design effort
Ultimately, the high-winged CX-HLS Boeing design was not used for the 747, although technologies developed for their bid had an influence.The original design included a full-length double-deck fuselage with eight-across seating and two aisles on the lower deck and seven-across seating and two aisles on the upper deck.However, concern over evacuation routes and limited cargo-carrying capability caused this idea to be scrapped in early 1966 in favor of a wider single deck design.The cockpit was, therefore, placed on a shortened upper deck so that a freight-loading door could be included in the nose cone; this design feature produced the 747's distinctive "bulge". In early models it was not clear what to do with the small space in the pod behind the cockpit, and this was initially specified as a "lounge" area with no permanent seating.
The Pratt & Whitney JT9D high-bypass turbofan engine was developed for the 747.
One of the principal technologies that enabled an aircraft as large as the 747 to be conceived was the high-bypass turbofan engine.The engine technology was thought to be capable of delivering double the power of the earlier turbojets while consuming a third less fuel. General Electric had pioneered the concept but was committed to developing the engine for the C-5 Galaxy and did not enter the commercial market until later.Pratt & Whitney was also working on the same principle and, by late 1966, Boeing, Pan Am and Pratt & Whitney agreed to develop a new engine, designated the JT9D to power the 747.
The project was designed with a new methodology called fault tree analysis, which allowed the effects of a failure of a single part to be studied to determine its impact on other systems.To address concerns about safety and flyability, the 747's design included structural redundancy, redundant hydraulic systems, quadruple main landing gear and dual control surfaces.Additionally, some of the most advanced high-lift devices used in the industry were included in the new design, in order to allow it to operate from existing airports. These included leading edge flaps running almost the entire length of the wing, as well as complex three-part slotted flaps along the rear.The wing's complex three-part flaps increase wing area by 21 percent and lift by 90 percent when fully deployed compared to their non-deployed configuration.
Boeing agreed to deliver the first 747 to Pan Am by the end of 1969. The delivery date left 28 months to design the aircraft, which was two-thirds of the normal time.The schedule was so fast paced that the people who worked on it were given the nickname "The Incredibles".Developing the aircraft was such a technical and financial challenge that management was said to have "bet the company" when it started the project.
Production plant
747 final assembly at the Boeing Everett Factory
As Boeing did not have a plant large enough to assemble the giant airliner, they chose to build a new plant. The company considered locations in about 50 cities,and eventually decided to build the new plant some 30 miles (48 km) north of Seattle on a site adjoining a military base at Paine Field near Everett, Washington.It bought the 780-acre (3.2 km2) site in June 1966.Developing the 747 had been a major challenge, and building its assembly plant was also a huge undertaking. Boeing president William M. Allen asked Malcolm T. Stamper, then head of the company's turbine division, to oversee construction of the Everett factory and to start production of the 747. To level the site, more than
4 million cubic yards (3.1 million m³) of earth had to be moved.Time was so short that the 747's full-scale mock-up was built before the factory roof above it was finished.The plant is the largest building by volume ever built, and has been substantially expanded several times to permit construction of other models of Boeing wide-body commercial jets.
Development and testing
Before the first 747 was fully assembled, testing began on many components and systems. One important test involved the evacuation of 560 volunteers from a cabin mock-up via the aircraft's emergency chutes. The first full-scale evacuation took two and a half minutes instead of the maximum of 90 seconds mandated by the Federal Aviation Administration (FAA), and several volunteers were injured. Subsequent test evacuations achieved the 90-second goal but caused more injuries. Most problematic was evacuation from the aircraft's upper deck; instead of using a conventional slide, volunteer passengers escaped by using a harness attached to a reel.Tests also involved taxiing such a large aircraft. Boeing built an unusual training device known as "Waddell's Wagon" (named for a 747 test pilot, Jack Waddell) that consisted of a mock-up cockpit mounted on the roof of a truck. While the first 747s were still being built, the device allowed pilots to practice taxi maneuvers from a high upper-deck position.
The prototype 747, City of Everett, at the Museum of Flight in Seattle, Washington
On September 30, 1968, the first 747 was rolled out of the Everett assembly building before the world's press and representatives of the 26 airlines that had ordered the airliner.Over the following months, preparations were made for the first flight, which took place on February 9, 1969, with test pilots Jack Waddell and Brien Wygle at the controls and Jess Wallick at the flight engineer's station. Despite a minor problem with one of the flaps, the flight confirmed that the 747 handled extremely well. The 747 was found to be largely immune to "Dutch roll", a phenomenon that had been a major hazard to the early swept-wing jets.
During later stages of the flight test program, flutter testing showed that the wings suffered oscillation under certain conditions. This difficulty was partly solved by reducing the stiffness of some wing components. However, a particularly severe high-speed flutter problem was solved only by inserting depleted uranium counterweights as ballast in the outboard engine nacelles of the early 747s.This measure caused anxiety when these aircraft crashed, as did China Airlines Flight 358 at Wanli in 1991 and El Al Flight 1862 at Amsterdam in 1992 which had 282 kilograms (620 lb) of uranium in the tailplane.Closeup of the 747 prototype's 16-wheel main undercarriage
The flight test program was hampered by problems with the 747's JT9D engines. Difficulties included engine stalls caused by rapid movements of the throttles and distortion of the turbine casings after a short period of service.The problems delayed 747 deliveries for several months and stranded up to 20 aircraft at the Everett plant while they awaited engine installation.The program was further delayed when one of the five test aircraft suffered serious damage during a landing attempt at Renton Municipal Airport, site of the company's Renton factory. On December 13, 1969 the test aircraft was being taken to have its test equipment removed and a cabin installed when pilot Ralph C. Cokely undershot the airport's short runway. The 747's right, outer landing gear was torn off and two engine nacelles were damaged. However, these difficulties did not prevent Boeing from taking one of the test aircraft to the 28th Paris Air Show in mid-1969, where it was displayed to the general public for the first time.The 747 achieved its FAA airworthiness certificate in December 1969, making it ready for introduction into service.
First Lady Pat Nixon visits the cockpit of the first commercial 747 during the christening ceremony,
January 15, 1970.
The huge cost of developing the 747 and building the Everett factory meant that Boeing had to borrow heavily from a banking syndicate. During the final months before delivery of the first aircraft, the company had to repeatedly request additional funding to complete the project. Had this been refused, Boeing's survival would have been threatened.The company's debt exceeded $2 billion, with the $1.2 billion owed to the banks setting a record for all companies. Allen later said, "It was really too large a project for us." Ultimately, the gamble succeeded, and Boeing held a monopoly in very large passenger aircraft production for many years.
Parts
A 747-400 has six million parts, half of which are fasteners.
A 747-400 has 171 miles (274 km) of wiring and 5 miles (8 km) of tubing.
A 747-400 consists of 147,000 pounds (66,150 kg) of high-strength aluminum.
The 747-400 has 16 main landing gear tires and two nose landing gear tires.
The 747-400 tail height is 63 feet 8 inches (19.4 m), equivalent to a six-story building.
Wings
The 747-400 wing weighs 95,000 pounds (43,090 kg), more than 30 times the weight of the first Boeing airplane, the 1916 B&W.
The 747-400 wing measures 5,600 square feet (524.9 m 2 ), an area large enough to hold 45 medium-sized automobiles.
Four World War I vintage JN4-D "Jenny" airplanes could be lined up on each of the Boeing 747 wings.
How much weight does an additional 6-foot (1.8-m) wingtip extension and winglet add to the 747-400 wing? None! A weight savings of approximately 5,000 pounds (2,270 kg) was achieved in the wing by using new aluminum alloys, which offset the weight increase of the wing tip extension and winglet
Engineering and Testing
Seventy-five thousand engineering drawings were used to produce the first 747.
The first 747 completed more than 15,000 hours of wind-tunnel testing.
The original 747 flight test program, which led to the airplane's certification for commercial service in December 1969, used five airplanes, lasted 10 months and required more than 1,500 hours of flying.
Flight
The 747 fleet has logged more than 42 billion nautical miles (77.8 billion kilometers), equivalent to 101,500 trips from the Earth to the moon and back.
The 747 fleet has flown 3.5 billion people - the equivalent of more than half of the world's population.
The 747-400ER range is approximately 7,713 nautical miles (14,297 km).
A 747-400 typically takes off at 180 mph (290 km/h), cruises at 565 mph (910 km/h) and lands at 160 mph (260 km/h).
For a typical international flight, one 747 operator uses about 5.5 tons (5,000 kg) of food supplies and more than 50,000 in-flight service items.
Engines
Engine thrust has grown from 43,500 pounds (19,730 kg) per engine on the early 747s to as much as 63,300 pounds (28,710 kg) on the current model.
The diameter of the 747 engine cowling is 8 feet 6 inches (2.6 m).
Fuel
The 747-400ER can carry more than 63,500 gallons of fuel (240,370 L), making it possible to fly extremely long routes, such as Los Angeles to Melbourne, Australia.
A 747-400 that flies 3,500 statute miles (5,630 km) and carries 126,000 pounds (56,700 kg) of fuel will consume an average of five gallons (19 L) per mile.
The 747-400 carries 3,300 gallons (12,490 L) of fuel in the horizontal (tail) stabilizer, allowing it to fly an additional 350 nautical miles.
Interior
The award-winning Boeing Signature Interior is available on both the 747-400 and 747-400ER.
At 31,285 cubic feet (876 cubic meters), the 747-400 has the largest passenger interior volume of any commercial airliner, which is equivalent to more than three houses each measuring 1,500 square feet (135 square meters).
The 747-400 has a redesigned "flexible" cabin interior that allows airlines to rearrange seats and class configuration overnight (in eight hours). They also permit 48-hour conversion times for changes in galley and lavatory locations.
Airline cargo handlers use the 747-400's lower-lobe cargo handling system to load or unload more than 65,000 pounds (30,000 kg) of cargo - the equivalent of 625 pieces of luggage combined with 20 tons of revenue freight - in less than 15 minutes.
The Wright Brothers' first flight at Kitty Hawk, N.C., could have been performed within the 150-foot (45-m) economy section of a 747-400.
There are 365 lights, gauges and switches in the new-technology 747-400 flight deck, reduced from 971 on earlier 747 models.
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