Sunday, August 10, 2008
Boeing 757
The Boeing 757-200, member of the popular 757/767 family of medium-sized airplanes, is a twin-engine short-to-medium-range jetliner incorporating advanced technology for exceptional fuel efficiency, low noise levels, increased passenger comfort and top operating performance. The 757 offers other virtues as well, including great versatility by reducing airport congestion. It can fly both long- and short-range routes and its broad use effectively lends itself to "hub-and-spoke" planning.
Designed to carry 200 passengers in a typical mixed-class configuration, the 757-200 can accommodate up to 228 passengers in charter service, putting its capacity between that of the Boeing 737-900, and the 757-300.
The 757-200 takeoff weights range from 220,000 pounds (99,800 kilograms) up to a maximum of 255,000 pounds (115,660 kilograms) for greater payload or range. A freighter configuration of the 757-200 also is available.
The 757-200 and twin-aisle 767 were developed concurrently, so both share the same technological advancements in propulsion, aerodynamics, avionics and materials. This commonality reduces training and spares requirements when both are operated in the same fleet. Because of these features, many airline operators operate both 757 and 767 airplanes.
Technical Features
High-bypass-ratio engines combined with the wing design help make the 757 one of the quietest, most fuel-efficient jetliners in the world. The engines have large-diameter fans that move more air outside and around the hot core, boosting efficiency while reducing noise. Noise containment is further aided by acoustic linings in the engine nacelles. Engines are available from Pratt & Whitney or Rolls-Royce in thrust ratings from 36,600 (162.8 kilonewtons) to 43,500 pounds (193.8 kilonewtons). When compared to any single-aisle jetliner in service today, the 757 is unsurpassed in fuel-efficiency. It consumes up to 43 percent less fuel per seat than older trijets.
The 757's wing is less swept and is thicker through the center than earlier aircraft, permitting a longer span. Its lower surface is slightly flatter, and the leading edge somewhat sharper. Taken together, these changes improve lift and reduce drag for greater aerodynamic efficiency and lower fuel consumption.
With the improved wing design, less engine power is required for takeoff and landing. Even with full passenger payload, the 757-200 can operate from runways as short as those used by the much smaller 737-200 jetliner -- about 5,500 feet (1,675 meters) for trips up to 1,740 nautical miles (3,220 kilometers). In addition, the 757 can reach a higher cruise altitude more quickly than many other jetliners.
These improvements reduce community noise of the already quiet 757-200 engines. In fact, noise levels are significantly lower than the requirements set forth in U. S. Federal Aviation Regulation Part 36, Stage 3, as well as ICAO (International Civil Aviation Organization) Annex 16 Chapter 3.
Lightweight materials contribute to the overall efficiency of the 757 models. Improved aluminum alloys, primarily in the wing skins, save 610 pounds (276 kilograms). Advanced composites such as graphite/epoxy are used in control surfaces (including rudder, elevators and ailerons), aerodynamic fairings, engine cowlings and landing gear doors for a weight savings of 1,100 pounds (500 kilograms). Another 650 pounds (295 kilograms) of weight savings is attributable to carbon brakes, which have the added advantage of longer service life than conventional steel brakes.
Flight Deck
The 757-200 flight deck, designed for two-crew member operation, pioneered the use of digital electronics and advanced displays. Those offer increased reliability and advanced features compared to older electro-mechanical instruments.
A fully integrated flight management computer system (FMCS) provides for automatic guidance and control of the 757-200 from immediately after takeoff to final approach and landing. Linking together digital processors controlling navigation, guidance and engine thrust, the flight management system assures that the aircraft flies the most efficient route and flight profile for reduced fuel consumption, flight time and crew workload.
The precision of global positioning satellite (GPS) system navigation, automated air traffic control functions, and advanced guidance and communications features are now available as part of the new Future Air Navigation System (FANS) flight management computer.
The captain and the first officer each have a pair of electronic displays for primary flight instrumentation. The electronic attitude director indicator displays airplane attitude and autopilot guidance cues. The electronic horizontal situation indicator displays a video map of navigation aids, airports, and the planned airplane route and can display a weather-radar image over these ground features.
The engine indicating and crew alerting system, often called EICAS, monitors and displays engine performance and airplane system status before takeoff. It also provides caution and warning alerts to the flight crew if necessary. EICAS monitoring also aids ground crews by providing maintenance information.
The 757-200 is available with a wind shear detection system that alerts flight crews and provides flight-path guidance to cope with it. Wind shear, caused by a violent down-burst of air that changes speed and direction as it strikes the ground, can interfere with a normal takeoff and landing.
Flight decks of the 757 and 767 are nearly identical and both aircraft have a common type-rating. Pilots qualified to fly one of the aircraft also can fly the other with only minimal additional familiarization.
Built-in test equipment helps ground crews troubleshoot avionics and airplane systems quickly for easier maintenance than on earlier aircraft. Structural maintenance needs are reduced, owing to new methods of corrosion protection including application of special sealants and enameling of major portions of the fuselage.
Interior Features
The interior of the 757-200 passenger cabin has been redesigned. The interior is the same as that developed for the Next-Generation 737 family. The 737 interior was revised based on the recommendations of airline customers. The new interior is designed to upgrade the overall look and aesthetics of the passenger cabin.
The new overhead stow bins and the new sculptured ceiling have smoother curves, giving the cabin a more open, spacious feeling. A handrail that extends along the bottom of the stow bins as well as a moveable cabin class divider also are available.
The 757-200 also is equipped with vacuum lavatories. For airlines, that means reduced service time.
Range Capability
The demonstrated reliability of the 757 has approval for extended-range twin (engine) operation, or ETOPS. In July 1990, the Federal Aviation Administration granted 180-minute ETOPS certification for 757-200s equipped with both the Rolls-Royce RB211-535E4 and RB211-535C engines. Previously, the FAA had certified the 757-200 equipped with RB211-535E4 engines for 120-minute operation in 1986. In April 1992, the FAA granted 180-minute ETOPS certification for the 757-200 equipped with Pratt & Whitney PW2000-series engines. This followed the FAA's previous certification of Pratt & Whitney PW2000-powered 757-200s for 120-minute operation in April 1990.
For added reliability on ETOPS flights, the 757 is available with extended range features, including a backup hydraulic-motor generator and an auxiliary fan to cool equipment in the electronics bay. High-gross-weight versions of the aircraft can fly 4,500 statute miles (7,240 kilometers) nonstop with full passenger payload. These system attributes contribute to the 757's versatility, allowing it to serve more markets.
History
The first 757-200 rolled out of the Boeing Renton, Wash., plant Jan. 13, 1982, and made its first flight Feb. 19, 1982. The U. S. Federal Aviation Administration certified the aircraft Dec. 21, 1982, after 1,380 hours of flight testing over a 10-month period.
First delivery of a 757-200 took place Dec. 22, 1982, to launch customer Eastern Airlines. Eastern placed the aircraft into service Jan. 1, 1983. On Jan. 14, 1983, the British Civil Aviation Authority certified the 757-200 to fly in the United Kingdom. British Airways, another launch customer for the 757-200, is now a major operator of the twinjet.
Final assembly of the 757-200 and the 757 Freighter is done in the Renton plant. Parts and assemblies for the airplanes are provided by Boeing plants in Auburn and Spokane, Wash.; Portland, Ore.; and Wichita, Kan., as well as by nearly 700 external suppliers.
The 757 Freighter
This first derivative of the 757 was announced by Boeing Dec. 30, 1985, when United Parcel Service ordered 20. Deliveries of these dedicated cargo airplanes began in Sept. 1987. The basic maximum takeoff weight of the 757F is 250,000 pounds (113,400 kilograms), with an option for 255,000 pounds (115,600 kilograms).
The 757F has no passenger windows or doors and no interior amenities. A large main-deck cargo door is installed in the forward area of the fuselage on the left-hand side. The flight crew boards the aircraft through a single entry door installed immediately aft of the flight deck on the left side of the aircraft.
The interior of the main-deck fuselage has a smooth fiberglass lining. A fixed rigid barrier installed in the front end of the main deck serves as a restraint wall between the cargo and the flight deck. A sliding door in the barrier permits access from the flight deck to the cargo area.
Up to 15 containers or pallets, each measuring 88 by 125 inches (223 by 317 centimeters) at the base, can be accommodated on the main deck of the 757F. Total main-deck container volume is 6,600 cubic feet (187 cubic meters) and the two lower holds of the airplane provide 1,830 cubic feet (51.8 cubic meters) for bulk loading. These provide a combined maximum revenue payload capability of 87,700 pounds (39,780 kilograms) including container weight. When carrying the maximum load, the 757F has a range of about 2,900 nautical miles (5,371 kilometers).
The 757F keeps ton-mile costs to a minimum with its two-person flight deck and twin high-bypass-ratio engines offering excellent fuel economy. This contrasts to older cargo-carrying aircraft in the standard-body class, such as 707s and DC-8s, that have three-person flight crews and are powered by four old-technology engines, which consume considerably more fuel.
The Boeing 757-200, member of the popular 757/767 family of medium-sized airplanes, is a twin-engine short-to-medium-range jetliner incorporating advanced technology for exceptional fuel efficiency, low noise levels, increased passenger comfort and top operating performance. The 757 offers other virtues as well, including great versatility by reducing airport congestion. It can fly both long- and short-range routes and its broad use effectively lends itself to "hub-and-spoke" planning.
Designed to carry 200 passengers in a typical mixed-class configuration, the 757-200 can accommodate up to 228 passengers in charter service, putting its capacity between that of the Boeing 737-900, and the 757-300.
The 757-200 takeoff weights range from 220,000 pounds (99,800 kilograms) up to a maximum of 255,000 pounds (115,660 kilograms) for greater payload or range. A freighter configuration of the 757-200 also is available.
The 757-200 and twin-aisle 767 were developed concurrently, so both share the same technological advancements in propulsion, aerodynamics, avionics and materials. This commonality reduces training and spares requirements when both are operated in the same fleet. Because of these features, many airline operators operate both 757 and 767 airplanes.
Technical Features
High-bypass-ratio engines combined with the wing design help make the 757 one of the quietest, most fuel-efficient jetliners in the world. The engines have large-diameter fans that move more air outside and around the hot core, boosting efficiency while reducing noise. Noise containment is further aided by acoustic linings in the engine nacelles. Engines are available from Pratt & Whitney or Rolls-Royce in thrust ratings from 36,600 (162.8 kilonewtons) to 43,500 pounds (193.8 kilonewtons). When compared to any single-aisle jetliner in service today, the 757 is unsurpassed in fuel-efficiency. It consumes up to 43 percent less fuel per seat than older trijets.
The 757's wing is less swept and is thicker through the center than earlier aircraft, permitting a longer span. Its lower surface is slightly flatter, and the leading edge somewhat sharper. Taken together, these changes improve lift and reduce drag for greater aerodynamic efficiency and lower fuel consumption.
With the improved wing design, less engine power is required for takeoff and landing. Even with full passenger payload, the 757-200 can operate from runways as short as those used by the much smaller 737-200 jetliner -- about 5,500 feet (1,675 meters) for trips up to 1,740 nautical miles (3,220 kilometers). In addition, the 757 can reach a higher cruise altitude more quickly than many other jetliners.
These improvements reduce community noise of the already quiet 757-200 engines. In fact, noise levels are significantly lower than the requirements set forth in U. S. Federal Aviation Regulation Part 36, Stage 3, as well as ICAO (International Civil Aviation Organization) Annex 16 Chapter 3.
Lightweight materials contribute to the overall efficiency of the 757 models. Improved aluminum alloys, primarily in the wing skins, save 610 pounds (276 kilograms). Advanced composites such as graphite/epoxy are used in control surfaces (including rudder, elevators and ailerons), aerodynamic fairings, engine cowlings and landing gear doors for a weight savings of 1,100 pounds (500 kilograms). Another 650 pounds (295 kilograms) of weight savings is attributable to carbon brakes, which have the added advantage of longer service life than conventional steel brakes.
Flight Deck
The 757-200 flight deck, designed for two-crew member operation, pioneered the use of digital electronics and advanced displays. Those offer increased reliability and advanced features compared to older electro-mechanical instruments.
A fully integrated flight management computer system (FMCS) provides for automatic guidance and control of the 757-200 from immediately after takeoff to final approach and landing. Linking together digital processors controlling navigation, guidance and engine thrust, the flight management system assures that the aircraft flies the most efficient route and flight profile for reduced fuel consumption, flight time and crew workload.
The precision of global positioning satellite (GPS) system navigation, automated air traffic control functions, and advanced guidance and communications features are now available as part of the new Future Air Navigation System (FANS) flight management computer.
The captain and the first officer each have a pair of electronic displays for primary flight instrumentation. The electronic attitude director indicator displays airplane attitude and autopilot guidance cues. The electronic horizontal situation indicator displays a video map of navigation aids, airports, and the planned airplane route and can display a weather-radar image over these ground features.
The engine indicating and crew alerting system, often called EICAS, monitors and displays engine performance and airplane system status before takeoff. It also provides caution and warning alerts to the flight crew if necessary. EICAS monitoring also aids ground crews by providing maintenance information.
The 757-200 is available with a wind shear detection system that alerts flight crews and provides flight-path guidance to cope with it. Wind shear, caused by a violent down-burst of air that changes speed and direction as it strikes the ground, can interfere with a normal takeoff and landing.
Flight decks of the 757 and 767 are nearly identical and both aircraft have a common type-rating. Pilots qualified to fly one of the aircraft also can fly the other with only minimal additional familiarization.
Built-in test equipment helps ground crews troubleshoot avionics and airplane systems quickly for easier maintenance than on earlier aircraft. Structural maintenance needs are reduced, owing to new methods of corrosion protection including application of special sealants and enameling of major portions of the fuselage.
Interior Features
The interior of the 757-200 passenger cabin has been redesigned. The interior is the same as that developed for the Next-Generation 737 family. The 737 interior was revised based on the recommendations of airline customers. The new interior is designed to upgrade the overall look and aesthetics of the passenger cabin.
The new overhead stow bins and the new sculptured ceiling have smoother curves, giving the cabin a more open, spacious feeling. A handrail that extends along the bottom of the stow bins as well as a moveable cabin class divider also are available.
The 757-200 also is equipped with vacuum lavatories. For airlines, that means reduced service time.
Range Capability
The demonstrated reliability of the 757 has approval for extended-range twin (engine) operation, or ETOPS. In July 1990, the Federal Aviation Administration granted 180-minute ETOPS certification for 757-200s equipped with both the Rolls-Royce RB211-535E4 and RB211-535C engines. Previously, the FAA had certified the 757-200 equipped with RB211-535E4 engines for 120-minute operation in 1986. In April 1992, the FAA granted 180-minute ETOPS certification for the 757-200 equipped with Pratt & Whitney PW2000-series engines. This followed the FAA's previous certification of Pratt & Whitney PW2000-powered 757-200s for 120-minute operation in April 1990.
For added reliability on ETOPS flights, the 757 is available with extended range features, including a backup hydraulic-motor generator and an auxiliary fan to cool equipment in the electronics bay. High-gross-weight versions of the aircraft can fly 4,500 statute miles (7,240 kilometers) nonstop with full passenger payload. These system attributes contribute to the 757's versatility, allowing it to serve more markets.
History
The first 757-200 rolled out of the Boeing Renton, Wash., plant Jan. 13, 1982, and made its first flight Feb. 19, 1982. The U. S. Federal Aviation Administration certified the aircraft Dec. 21, 1982, after 1,380 hours of flight testing over a 10-month period.
First delivery of a 757-200 took place Dec. 22, 1982, to launch customer Eastern Airlines. Eastern placed the aircraft into service Jan. 1, 1983. On Jan. 14, 1983, the British Civil Aviation Authority certified the 757-200 to fly in the United Kingdom. British Airways, another launch customer for the 757-200, is now a major operator of the twinjet.
Final assembly of the 757-200 and the 757 Freighter is done in the Renton plant. Parts and assemblies for the airplanes are provided by Boeing plants in Auburn and Spokane, Wash.; Portland, Ore.; and Wichita, Kan., as well as by nearly 700 external suppliers.
The 757 Freighter
This first derivative of the 757 was announced by Boeing Dec. 30, 1985, when United Parcel Service ordered 20. Deliveries of these dedicated cargo airplanes began in Sept. 1987. The basic maximum takeoff weight of the 757F is 250,000 pounds (113,400 kilograms), with an option for 255,000 pounds (115,600 kilograms).
The 757F has no passenger windows or doors and no interior amenities. A large main-deck cargo door is installed in the forward area of the fuselage on the left-hand side. The flight crew boards the aircraft through a single entry door installed immediately aft of the flight deck on the left side of the aircraft.
The interior of the main-deck fuselage has a smooth fiberglass lining. A fixed rigid barrier installed in the front end of the main deck serves as a restraint wall between the cargo and the flight deck. A sliding door in the barrier permits access from the flight deck to the cargo area.
Up to 15 containers or pallets, each measuring 88 by 125 inches (223 by 317 centimeters) at the base, can be accommodated on the main deck of the 757F. Total main-deck container volume is 6,600 cubic feet (187 cubic meters) and the two lower holds of the airplane provide 1,830 cubic feet (51.8 cubic meters) for bulk loading. These provide a combined maximum revenue payload capability of 87,700 pounds (39,780 kilograms) including container weight. When carrying the maximum load, the 757F has a range of about 2,900 nautical miles (5,371 kilometers).
The 757F keeps ton-mile costs to a minimum with its two-person flight deck and twin high-bypass-ratio engines offering excellent fuel economy. This contrasts to older cargo-carrying aircraft in the standard-body class, such as 707s and DC-8s, that have three-person flight crews and are powered by four old-technology engines, which consume considerably more fuel.
The story of the B757
After a slow sales start, the medium range single aisle 757 has become yet another sales success story for Boeing.
Boeing considered a number of proposals for a successor to the 727 trijet during the 1970s, with many of these designs featuring the nose and Ttail of the earlier jet. It was not until later in that decade however that Boeing settled on a more conventional design featuring the same cross section as the 727 (not to mention the 737, 707 and 720) but with the fuselage considerably longer in length, an all new wing, nose and flightdeck and fuel efficient high bypass turbofan engines.
Boeing launched development of the 757 in March 1979 following orders from British Airways and Eastern. Developed in tandem with the larger widebody 767 the two types share a number of systems and technologies, including a common early generation EFIS flightdeck.
First flight was on February 19 1982 and the 757 entered service in January the following year. Subsequent versions to appear are the 757-200PF Package Freighter, a pure freighter, and the 757-200M Combi (only one has been built). The standard passenger aircraft is designated the 757-200, there being no 100. The stretched 757-300 is described separately.
Initial sales of the 757 were fairly slow, however orders picked up significantly in the mid to late 1980s as traffic on routes previously served by smaller 727s and 737s grew to require the 757's extra capacity. Today 757 sales comfortably exceed those of the 767, a position that was reversed until the late 1980s.
Boeing considered a number of proposals for a successor to the 727 trijet during the 1970s, with many of these designs featuring the nose and Ttail of the earlier jet. It was not until later in that decade however that Boeing settled on a more conventional design featuring the same cross section as the 727 (not to mention the 737, 707 and 720) but with the fuselage considerably longer in length, an all new wing, nose and flightdeck and fuel efficient high bypass turbofan engines.
Boeing launched development of the 757 in March 1979 following orders from British Airways and Eastern. Developed in tandem with the larger widebody 767 the two types share a number of systems and technologies, including a common early generation EFIS flightdeck.
First flight was on February 19 1982 and the 757 entered service in January the following year. Subsequent versions to appear are the 757-200PF Package Freighter, a pure freighter, and the 757-200M Combi (only one has been built). The standard passenger aircraft is designated the 757-200, there being no 100. The stretched 757-300 is described separately.
Initial sales of the 757 were fairly slow, however orders picked up significantly in the mid to late 1980s as traffic on routes previously served by smaller 727s and 737s grew to require the 757's extra capacity. Today 757 sales comfortably exceed those of the 767, a position that was reversed until the late 1980s.
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