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757-200 Background
The Boeing 757-200,
member of the popular 757/767 family of medium-sized airplanes, is
a twin-engined, medium-to-long-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 194 passengers in a typical mixed-class configuration, the
757-200 can accommodate up to 239 passengers in charter service, putting
its capacity between that of the Boeing 737-400 or -700 and the 757-300.
The 757-200
takeoff weights range from 220,000 pounds (99,800 kg) up to a maximum
of 255,000 pounds (115,660 kg) for greater payload or range. A freighter
configuration of the 757-200 is also available.
The 757-200
and dual-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 will 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 pounds of thrust (162.8 kilonewtons) to 43,500 pounds
of thrust (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 m) for trips up to 2,000 statute 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 powerplants on the 757-200.
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 kg). 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 kg). Another 650 pounds (295 kg) 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-crewmember 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
ensures 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 system (GPS) 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 it 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 downburst 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 can fly any
of the seven 757/767 family members 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, Washington, plant on
Jan. 13, 1982, and made its first flight Feb. 19, 1982. The FAA certified
the aircraft on Dec. 21, 1982, after 1,380 hours of flight testing over
a 10-month period. The first 757-300 rolled out in 1998.
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 statute miles (4,020 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.
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