Астрономия и авиация
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 extra seating, and to allow the aircraft to be easily converted...
Ministry of Education and Science of Ukraine
National Aviation University
Institute of Information Diagnostic Systems
Department of Aviation Computer-Integration Complexes
Done by: Yuliya Svyrydenko
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. Its iconic "hump" upper deck along the forward part of the aircraft make it among the world's most recognizable aircraft and was the first wide-body produced. Manufactured by Boeing's Commercial Airplane unit in the United States, the original version of the 747 had two and a half times greater capacity than 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 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 (development of which was announced in the early 1960s) to render the 747 and other subsonic airliners obsolete, while the demand for subsonic cargo aircraft would be robust well into the future. The 747 was expected to become obsolete after 400 were sold, but it exceeded critics' expectations with production passing the 1,000 mark in 1993. By July 2014, 1,500 aircraft had been built, with 51 of the 747-8 variants remaining on order.
The 747-400, the most common passenger version in service, has a high-subsonic cruise speed of Mach 0.850.855 (up to 570 mph or 920 km/h) with an intercontinental range of 7,260 nautical miles (8,350 mi or 13,450 km). 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.
The Boeing 747 is a large, wide-body (two-aisle) airliner with four wing-mounted engines. The wings have a high sweep angle of 37.5 degrees for a fast, efficient cruise of Mach 0.84 to 0.88, depending on the variant. The sweep also reduces the wingspan, allowing the 747 to use existing hangars. Seating capacity is more than 366 with a 343 seat arrangement (a cross section of 3 seats, an aisle, 4 seats, another aisle, and 3 seats) in economy class and a 232 arrangement in first class on the main deck. The upper deck has a 33 seat arrangement in economy class and a 22 arrangement in first class
Cargolux 747-400F with the nose loading door open
Cargolux 747-400F with the nose loading door open
Raised above the main deck, the cockpit creates a hump. The raised cockpit allows front loading of cargo on freight variants. The upper deck behind the cockpit provides space for a lounge or extra seating. The "stretched upper deck" became available as an option on the 747-100B variant and later as standard on the 747-300. The 747 cockpit roof section also has an escape hatch from which crew can exit in the event of an emergency if they cannot exit through the cabin.
The 747's maximum takeoff weight ranges from 735,000 pounds (333,400 kg) for the −100 to 970,000 lb (439,985 kg) for the −8. Its range has increased from 5,300 nautical miles (6,100 mi, 9,800 km) on the −100 to 8,000 nmi (9,200 mi, 14,815 km) on the −8I.
The 747 has multiple structural redundancy including four redundant hydraulic systems and four main landing gears with four wheels each, which provide a good spread of support on the ground and safety in case of tire blow-outs. The redundant main gear allows for landing on two opposing landing gears if the others do not function properly. In addition, the 747 has split control surfaces and was designed with sophisticated triple-slotted flaps that minimize landing speeds and allow the 747 to use standard-length runways. For transportation of spare engines, 747s can accommodate a non-functioning fifth-pod engine under the port wing of the aircraft between the inner functioning engine and the fuselage.
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 was displayed to the public for the first time on 30 September 1968.
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 (622 lb) of uranium in the tailplane.
A view of the 747's four main landing gear, each with four wheels
Closeup of the 747 prototype's 16-wheel main landing gear
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 .
The First Lady Pat Nixon sitting in the cockpit of the first commercial 747 during the christening ceremony in 1970
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.