demand has sized, shaped and launched the newest member of the
Boeing widebody family, the 777. The airplane design offers
features, innovations and approaches to aircraft development
that set the standard for delivering value to airlines. The
777 -- the world's largest twinjet -- is available in three
models: an initial 777-200 model, a 777-200ER (extended range)
model and a larger 777-300 model.
15, 1996, the 777 was named winner of the prestigious Robert
J. Collier Trophy by the U.S. National Aeronautic Association.
The award honored the 777 as top aeronautical achievement of
United Airlines, All Nippon Airways, British Airways, Japan
Airlines and Cathay Pacific were among a number of carriers
with whom Boeing held intensive discussions, including many
group sessions, to define and develop the new airplane's
configuration. The participating airlines represented a full
range of operations in terms of route structure, traffic loads
and service frequency. Their input to the design process
helped ensure that the final product has the broadest possible
application to the needs of the world's airlines.
every respect, the 777 design responds to market needs and
customer preferences. The result is an airplane offering cabin
spaciousness and flexibility found in no other jetliner and
many features to enhance reliability and productivity -- all
with lower operating costs. The 777 provides the most payload
and range capability and growth potential in the medium-size
benefit of the intensive customer dialogue was a consensus
that many items traditionally offered as optional, or special
request, features on other airplanes should be standard (or
basic) equipment on the 777 because they are so frequently
specified by most airlines. About 80 such items -- including
satellite communication and global positioning systems -- are
basic to the airplane. This reduces variability during design
and production, while providing the airlines with a more
economical equipment package.
The 777 wing uses the most aerodynamically efficient airfoil
ever developed for subsonic commercial aviation. In a further
refinement of designs introduced on the Boeing 757 and 767,
the 777 wing features a long span with increased thickness
while achieving higher cruise speeds. This advanced wing
enhances the airplane's ability to climb quickly and cruise at
higher altitudes than competing airplanes. It also allows the
airplane to carry full passenger payloads out of many
high-elevation, high-temperature airfields.
volume requirements for the 777 are accommodated entirely
within the wing and its structural center section. For the
initial airplane, fuel capacity is 31,000 gallons (117,335 L),
while the longer-range model and the 777-300 model can carry
up to 45,220 gallons (171,155 L).
helping to design the 777 encouraged Boeing to commit to the
performance capabilities of an optimum wing, which has a span
of 199 feet 11 inches (60.9 m).
The three leading engine manufacturers have developed more
efficient and quieter turbofans to power the 777, and all
three have been selected by 777 customers. Engine selection by
the airlines is split by roughly one-third for each of the
initial airplane, these engines are rated in the 73,400- to
77,000-pound thrust class. For the extended-range model and
the 777-300, these engines will be capable of thrust ratings
in the 83,600-to-98,000-pound category. The engines could be
developed to even higher thrust ratings, depending on future
payload and range requirements.
three engines offer excellent fuel efficiency, while allowing
the 777 to be as quiet as a 767, even though the 777 engines
provide 40 percent more power. Key factors in this performance
are new, larger-diameter fans with wide-chord fan blade
designs and bypass ratios ranging from 6-to-1 to as high as
9-to-1. This compares to the typical 5-to-1 ratio for the
engines of previous twin-aisle jets.
& Whitney is offering the PW4000 series of engines,
General Electric is offering its all-new GE90 series, and
Rolls-Royce is offering the Trent 800 series of engines.
New, lightweight, cost-effective structural materials are used
in several 777 applications. For example, an improved aluminum
alloy is used in the upper wing skin and stringers. Known as
7055, this alloy offers greater compression strength than
current alloys, enabling designers to save weight and also
improve corrosion and fatigue resistance.
in the development and fabrication of weight-saving advanced
composite materials is evident in the 777. Carbon fibers
embedded in recently available toughened resins are found in
the vertical and horizontal tails. The floor beams of the
passenger cabin also are made of these advanced composite
composite applications include those on secondary structures
such as aerodynamic fairings. Composites, including resins and
adhesives, account for 9 percent of the 777's structural
weight, compared to about 3 percent on other Boeing jets.
Deck and Airplane Systems
In response to airline preference expressed during the
prelaunch definition phase, the layout of the 777 flight deck
is in a horizontal format similar to that of the 747-400.
Principal flight, navigation and engine information is
presented on six large display screens.
these displays resemble conventional cathode ray tube (CRT)
screens, they incorporate advanced liquid-crystal display
technology. The depth of the new "flat-panel
displays" is about half that of CRTs. In addition to
saving space, the new displays weigh less and require less
power. They also generate less heat, which contributes to
greater reliability and a longer service life. The displays do
not require the heavy, complex air conditioning apparatus
needed to cool equipment on current flight decks. Pilots
appreciate that flat panel displays remain clearly visible in
all conditions, even direct sunlight.
multipurpose control display units (CDU), installed in the
center aisle stand, provide data display and entry
capabilities for flight management functions and are the
primary interface with an integrated Airplane Information
Management System (AIMS). The CDUs have color displays, again
in response to market preferences. Adding color allows pilots
to assimilate the information more quickly.
provides flight and maintenance crews all pertinent
information concerning the overall condition of the airplane,
its maintenance requirements and its key operating functions,
including flight, thrust and communications management.
flight crew transmits control and maneuvering commands through
electrical wires, augmented by computers, directly to
hydraulic actuators for the elevators, rudder, ailerons and
other control surfaces. This three-axis
"fly-by-wire" flight-control system saves weight,
simplifies factory assembly compared to conventional
mechanical systems relying on steel cables, and requires fewer
spares and less maintenance in airline service.
part of the 777 systems is a Boeing-patented two-way digital
data bus, which has been adopted as a new industry standard:
ARINC 629. It permits airplane systems and their computers to
communicate with one another through a common wire path (a
twisted pair of wires) instead of through separate one-way
wire connections. This further simplifies assembly and saves
weight, while increasing reliability through a reduction in
the amount of wires and connectors. There are 11 of these
ARINC 629 pathways in the 777.
was the first Boeing model to be equipped with the Enhanced
Ground Proximity Warning System (EGPWS) as standard equipment.
The EGPWS displays potentially threatening terrain and gives
an audible alert up to a minute in advance of possible terrain
conflict, compared with 10 to 15 seconds for previous systems.
It incorporates a proprietary digital terrain map, which it
continuously compares to aircraft position data from the
feature in the 777-300 flight deck is the addition of a Ground
Maneuver Camera System (GMCS), designed to assist the pilot in
ground maneuvering of the 777-300 with camera views of the
nose gear and main gear areas. The cameras are on the leading
edge of the left and right horizontal stabilizers and the
underside of the fuselage and are used during ground
maneuvering. The images are displayed at the Multi-Functional
Display positions in the flight deck in a three-way split
1993, the 777 flight deck received accolades from the
Industrial Designers Society of America. For the second year
in a row, the 777 received the society's Industrial Design
Excellence Award for its flight deck design..
In addition to being one of the most spacious passenger cabins
ever developed, the 777 interior offers operators unsurpassed
configuration flexibility. Flexibility zones have been
designed into the cabin areas specified by the airlines,
primarily at the airplane's doors. In 1-inch increments,
galleys and lavatories can be positioned anywhere within these
zones, which are pre-engineered to accommodate wiring,
plumbing and attachment fixtures. Passenger service units and
overhead stowage compartments are designed for quick removal
without disturbing ceiling panels, air conditioning ducts or
support structure. A typical 777 configuration change is
expected to take as little as 72 hours, while such a change
might take two to three weeks on existing aircraft.
overhead compartments provide passengers with increased
stowage capacity. Outboard as well as center stowage units are
designed to open downward for convenient loading. When closed,
they fit neatly into the streamlined contours of the interior
architecture and allow ample overhead clearance.
improved, more efficient in-flight service, the 777 is
equipped with an advanced cabin management system. Linked to a
computerized control console, the cabin management system
assists cabin crews with many tasks and allows airlines to
provide new services for passengers, including a digital sound
system comparable to the most state-of-the-art home stereo or
compact disc players.
Industrial Design Excellence Award was awarded to the
passenger cabin of the new Boeing 777 jetliner, the first time
the Industrial Designers Society of America honored an
survey of nearly 6,000 passengers flying on long-range routes
to and from Europe in first, business and economy classes
revealed an overwhelming preference for the 777. The survey,
conducted in 1999 by six airlines based in Europe and the
Middle East, found that the Boeing 777 was preferred by more
than three out of four passengers who had flown aboard both
the 777 and the Airbus A330/340 airplanes.
The fuselage cross-section of the 777 is circular and large
enough to accommodate not only a spacious passenger cabin, but
excellent capacity in the lower hold. The lower-hold
mechanized cargo-handling system is compatible with all unit
load devices (ULD) and pallets. One of the container
arrangements utilizes LD-3s loaded side by side. The 777-200
can accommodate a maximum of 32 LD-3 containers plus 600 cubic
feet (17 m3) of bulk-loaded cargo for total
lower-hold volume of 5,656 cubic feet (160.17 m3).
The 777-300 can accommodate a maximum of 44 LD-3 containers
plus the same amount of bulk-loaded cargo as the -200 model
for a total lower-hold volume of 7,552 cubic feet (213.8 m3).
The main landing gear for the 777 is in a standard two-post
arrangement but features six-wheel trucks, instead of the
conventional four-wheel units. This provides the main landing
gear with a total of 12 wheels for better weight distribution
on runways and taxi areas and avoids the need for a
supplemental two-wheel gear under the center of the fuselage.
Another advantage is that the six-wheel trucks allow for a
more economical brake design. The 777 landing gear is the
largest ever incorporated into a commercial airplane.
Reliability and Quality
New design and testing initiatives helped ensure the highest
possible levels of reliability on the very first 777, compared
to what had been possible on previous jetliner introductions.
teams, which bring together representatives of the diverse
disciplines involved in airplane development, as well as
suppliers and representatives of airline customers, allowed
team members to work concurrently on the 777 structural and
the "market-driven" approach, four 777 customers had
on-site representatives working side by side with Boeing
designers to ensure that the new airplane filled their needs.
United Airlines, All Nippon Airways, British Airways and Japan
Airlines had teams of between two to four engineers on site,
who were actively involved in developing the 777.
first time, digital computers were used by Boeing engineers to
design and electronically preassemble the entire airplane,
increasing accuracy and improving quality. New laboratory
facilities enabled the various airplane systems to be tested
together as a single integrated entity in simulated flight
conditions -- before the first jetliner took to the air. This
allowed a smoother transition to flight testing and service
other initiatives, standard certification flight tests were
supplemented with 1,000 flight cycles on each airframe-engine
combination for the initial 777-200 model to demonstrate
reliability in simulated airline operating environments. The
Boeing-United Airlines 1,000-cycle flight tests for the Pratt
& Whitney engine were completed on May 22, 1995. In
addition, engine makers and the many suppliers of parts for
the airplane intensified their own development and testing
efforts to ensure that their products met airline
thorough test program demonstrated the design features needed
to obtain approval for extended-range twin-engine operations
(ETOPS). All 777s are ETOPS-capable, as part of the basic
design. To ensure reliability, the 777 with Pratt &
Whitney engines was tested and flown under all appropriate
conditions to prove it is capable of flying up to 180-minute
ETOPS missions. On May 30, 1995, the 777 became the first
airplane in aviation history to earn Federal Aviation
Administration (FAA) approval to fly ETOPS at service entry.
On May 4, 1998, the 777-300 achieved another historic
milestone by becoming the first commercial airplane to receive
type certification and 180-minute ETOPS the same day.
The skills and resources of a number of international
aerospace companies contributed to the design and production
of the 777. Firms in Europe, Canada, Asia/Pacific and the
United States provided components and portions of the
structure to Boeing.
largest single overseas participant is the Japanese aerospace
industry. Led by Mitsubishi Heavy Industries, Kawasaki Heavy
Industries and Fuji Heavy Industries, this group of companies
is continuing its long-standing business relationship with
Boeing. Together, these firms helped design and build about 20
percent of the airframe structure.