Boeing 777-200
American Airlines
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Boeing 777-200
American Airlines
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Boeing 777-200
United Airlines (Continental ...
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Boeing 777
The Boeing 777 is a family of long range widebody twin engine airliners built
by Boeing Commercial Airplanes. It carries between 305 and 550 passengers and
has a range from 5,600 to 8,870 nautical miles (10,400 to 16,400 km). The first
flight of the 777 was in 1994.
Distinguishing features of the 777 include the set of six wheels on each main
landing gear, its perfectly circular fuselage cross section, and the blade-like
rear tailcone.
History
In the 1970s Boeing unveiled new models to replace and expand its line up.
They were the twin engined 757 to replace the venerable 727, the twin engined
767 to challenge the Airbus A300, and the 777 tri-jet to compete with the DC-10
and the Lockheed TriStar. It was a tri-jet airplane based on a re-winged
767 design, with two main variants:
A transcontinental airplane transporting 175 on trips up to 5,000 km
(2,700 nautical miles), and an intercontinental version capable of flying over
8,000 km (4,320 nautical miles) with the same passenger load.
The twinjets were launched and the 777 tri-jet was cancelled much like how
the tri-jet concept of the Boeing 757 was also cancelled. Boeing's choice to
not proceed with the 777 was influenced by the design complexities of tri-jet
aircraft, the absence of an engine with thrust in the range of 40,000 lbf
(178 kN), and the success of the 757 and 767, particularly with the benefit of
ETOPS regulations of the 1980s.
Boeing had a big gap in its product line between the 767-300ER and the 747-400
in terms of size and range, and realized the potential of such an airplane.
The DC-10 and Lockheed Tristar, being of 1960s design, were also ripe for
replacement. In the meantime, Airbus developed the A330 and A340 to fulfill
that requirement.
The initial proposal from Boeing was simply to enlarge the 767, resulting
in the 767-X concept. It was similar to a 767 but with a longer fuselage and
larger wings seating about 340 passengers with a maximum range of 7,300
nautical miles (13,500 km).
The airlines were unimpressed with the 767-X. They wanted short to
intercontinental range capability, cabin cross section similar to the 747, a
fully flexible cabin configuration, and an operating cost lower than any 767
stretch. The result was a new design, the 777 twinjet.
The design phase of the 777 differed from previous Boeing jetliners. For the
first time the airlines and their passengers had a role in the development
of the plane. The major airlines consulted were United Airlines, ANA, British
Airways, JAL, and Cathay Pacific. The "Working Together" philosophy, as Boeing
called it, meant that the 777 was their most customer oriented aircraft yet.
The 777 was also the first commercial aircraft to be designed entirely by
computer. No paper drawings were ever produced as everything was created on
a 3D CAD software system known as CATIA. This allowed a virtual 777 to be
assembled in cyberspace, allowing engineers to examine for interferences
and to test if the many thousands of parts would fit together properly before
costly physical prototypes were manufactured.
Singapore Airlines is the largest operator of Boeing 777s with 57 currently
in service and more on option.
To this day 671 orders have been placed for the 777 from 38 different
customers.
Technological features
To satisfy airline requirements technologies new to Boeing were employed,
although much of this technology was already in service on Airbus aircraft.
These new features included:
-Honeywell LCD glass cockpit flight displays
-Fully digital fly-by-wire flight controls
-Fully software configurable avionics
-Large scale use of composites (10% by weight)
-Fiber optic avionics network
-Very large turbofan engines
Fortunately for Boeing, work done on the previously cancelled Boeing 7J7
validated the chosen technologies.
The 777 first flew on June 14, 1994, and underwent a flight test program more
extensive than any other Boeing model. The FAA awarded full 180-minute ETOPS
clearance ("ETOPS-180") for PW4074 777-200s on May 30, 1995. The 777 was the
first aircraft to carry an ETOPS-180 rating at its entry into service.
A notable design feature is Boeing's decision to retain conventional control
yokes rather than fit sidestick controllers as used in many fly-by-wire fighter
aircraft and in some Airbus models. Boeing viewed 'stick and rudder' controls
as being more intuitive for pilots.
Variants
Boeing uses two characteristics to define their 777 models. The first is the
airframe size which affects the amount of passengers and cargo that can be
carried. The 777-200 and derivatives are the base size while the aircraft
was stretched into the 777-300.
The second characteristic is range. Boeing defines three segments:
A market - 3,900 to 5,200 nautical miles (7,200 to 9,700 km)
B market - 5,800 to 7,700 nautical miles (10,800 to 14,250 km)
C market - 8,000 nautical miles (14,800 km) and greater
These markets are also used to compare the 777 to its archrival, the Airbus A340.
When referring to variants of the 777 Boeing and the airlines often collapse
the model (777) and the capacity designator (200 or 300) into a smaller form of
either 772 or 773. Subsequent to that, they may or may not append the range
identifier. So the base 777-200 may be referred to as a "772" or "772A" while
a 777-300ER would be referred to as a "773ER" or "773B". Any of these notations
may be found in aircraft manuals or airline timetables.
777-100
The 777-100 (771B) would have been a lower capacity, B market version of the
777. As the aircraft would have been heavy and have high per passenger costs
it was not selected for production. History has not been kind to "shrinks" of
aircraft, the Airbus A318, Boeing 747SP, Boeing 737-600, and McDonnell Douglas
MD-87 are excellent examples. The 777-100 was offered to Delta Air Lines and
Continental Airlines as an option to replace their ageing L-1011 and DC-10 fleets.
Both airlines rejected the offer which led Boeing to make the 767-400ER, which
was designed to meet both of their specifications. The 787-9 will be targeted
at this same market segment.
777-200
The 777-200 (772A) was the initial B-market model. The first customer delivery
was to United Airlines in May, 1995. It is available with a maximum takeoff
weight (MTOW) from 229 to 247 tonnes and range capability between 3780 and 5150
nautical mile (7000 to 9500 km).
The basic 777-200 is powered by two 74,000 lbf (329 kN) Pratt & Whitney
PW4074 turbofans, 75,000 lbf (334 kN) General Electric GE90-75Bs, or 75,000
lbf (334 kN) Rolls Royce Trent 875s.
The direct Airbus equivalent is the A330-300.
777-200ER
Originally known as the 777-200IGW for "increased gross weight", the
longer range B market 777-200ER (772B) features additional fuel capacity
with increased MTOW range from 263 to 286 tonnes and range capability between
6000 and 7700 nautical miles (11,000 to 14,300 km). The first 777-200ER was
delivered to British Airways in February, 1997.
The 777-200ER can be powered by any two of a number of engines: the 84,000 lbf
(374 kN) PW4084 or Trent 884, the 85,000 lbf (378 kN) GE90-85B, the 90,000 lbf
(400 kN) PW4090, GE90-90B1, or Trent 890, or the 92,000 lbf (409 kN) GE90-92B.
On April 2, 1997, a Boeing 777-200ER, tail registration 9M-MRA
(dubbed the "Super Ranger") of Malaysia Airlines, broke the Great Circle
Distance Without Landing record for an airliner by flying east (the long way)
from Boeing Field, Seattle, to Kuala Lumpur, Malaysia, covering the distance
of 20,044 km in 21 hours, 23 minutes.
The direct Airbus equivalent is the A340-300.
777-200LR Worldliner
Boeing claims the C market 777-200LR (772C) will be the world's longest ranging
commercial airliner, capable of flying 9420 nautical miles (17,446 km) in 18
hours. It will achieve this with huge 110,000 lbf (489 kN) thrust GE90-110B1L
turbofans, a significantly increased MTOW, and optional auxiliary fuel tanks in
the rear cargo hold. Other new features include raked wingtips, a new main
landing gear, and additional structural strengthening. The roll-out was on
February 15, 2005. The first flight was March 8, 2005, with EIS in
January, 2006. After its introduction into service the only mass produced
aircraft with greater unrefuelled range will be the KC-10 Extender.
The direct Airbus equivalent is the A340-500.
The first Boeing 777-200LR will be delivered to Pakistan International Airlines
(PIA) in January, 2006.
Other customers include Air India, (subject to Government Approval) and EVA Air.
Air Canada cancelled orders for 777-200LR due to pilot contract issues.
Emirates, Jet Airways, and Qatar Airways expressed interest in ordering the
Boeing 777-200LR.
777-300
The stretched A market 777-300 (773A) is designed as a replacement for
747-100s and -200s. Compared to the older 747s, the stretched 777 has
comparable passenger capacity and range, but burns one third less fuel and
demands 40% lower maintenence costs.
It features a 33 ft 3 in (10.1 m) fuselage stretch over the baseline 777-200
allowing seating for up to 550 passengers in a single class, high density
configuration and is also 13 tonnes heavier. The 777-300 has tailskid and
ground maneuvring cameras mounted on the horizontal tail and underneath the
forward fuselage to aid pilots during taxi due to the aircraft's enormous length.
It was awarded type certification simultaneously from the U.S. FAA and European
JAA and was granted 180 min ETOPS approval on May 4, 1998. It entered service
with Cathay Pacific later that month.
The typical operating range with 386 three class passengers is 5720 nautical
miles (10,600 km). It is typically powered by two of the following engines:
90,000 lbf (400 kN) PW4090 turbofans, 92,000 lbf (409 kN) Trent 892 or General
Electric GE90-92Bs, or 98,000 lbf (436 kN) PW-4098s.
This aircraft has no direct Airbus equivalent but the A340-600 is offered in
competition.
777-300ER
The B market 777-300ER (773B) series is a long range version of 777-300 and
is designed as a replacement for the 747-400. This is a result of Boeing's
strategy to target the 747 series as cargo freighters rather than passenger
aircraft.
The 777-300ER contains many modifications including the GE90-115B engines
which are currently the world's most powerful jet engine with 115,300 lbf
(513 kN) thrust. Other features include raked wingtips, a new main landing gear,
extra fuel tanks, as well as strengthened fuselage, wings, empennage,
nose gear, engine struts, and nacelles. The range on initial versions is 7,250
nautical miles (13,400 km) with a 365 passenger three class configuration,
though after July, 2004, the 300ER will have a range of 7,880 nautical
miles (14,594 km). The 777-300ER program was launched by Air France,
though, for political reasons, Japan Airlines was advertised as the launch
customer. The first flight of the 777-300ER was February 24, 2003.
The direct Airbus equivalent is the A340-600.
777 Freighter
The 777 Freighter (777F) is an all cargo variant of the 777. Boeing has had some
need for a large freighter to replace older 747F and MD-11F freighters.
The increased payload capability of the 777-200LR has allowed the company
to begin marketing a cargo derivation. The model was officially offered starting
on November 15, 2004.
The 777F promises excellent operating economics compared to existing freighters.
The aircraft has a large interior volume and a high thrust-to-weight ratio.
The large wings allow for a low wing loading. The 777F will have a payload of
101 tons. This compares favorably to that of the much larger 747-400F which
has a payload of 124 tons but is less than the 150 tons of the A380-800F.
With the extra belly fuel tanks sacrificed in the interest of payload, the
777F will not range as far as the passenger variant it is based upon.
However, the 777F will be the longest-ranged freighter in the world with a
range of 5,200 miles (8,400 km). Compared to the 747F, the 777F will lack
direct loading of cargo via the nose, but this will not be an issue for most
customers.
The 777F will be equipped with the 110,000 lbf (489 kN) GE90-110B engines from
the 777-200LR. However, the 115,000 lbf (513 kN) GE90-115B engines from the
777-300ER may be offered as an option to increase MTOW.
Potential customers are Lufthansa Cargo, Federal Express, United Parcel Service,
Emirates, and EVA Cargo. EIS is 2008. Air France KLM signed on as the 777F
launch customer on March 25, 2005. The order for 7 aircraft is worth US$1.5
billion at list prices and the first delivery will be in 2008.
Airbus has no comparable aircraft, the A380-800F is the closest equivalent but
is larger. The A380-800F is better suited for bulky parcel freight service
while the 777F is geared towards denser cargo. The most directly comparable
aircraft is the McDonnell Douglas MD-11F which also lacks the 777F's range
as well as payload capability.
Some Boeing 777 facts
-The 777-300ER is the third largest commercial passenger airplane
after the 747-400 and the new Airbus A380-800 and has been tested with
a maximum takeoff weight (MTOW) of 351 metric tons.
-The 777's undercarriage is the largest ever used in a commercial
jetliner and its tires are the largest ever fitted to a commercial
aircraft.
-The 777-300ER has been tested flying with only one working engine for
as long as six hours 29 minutes over the Pacific Ocean as part of its
ETOPS trials. (Note: 3 hours successful and reliable operation of
one-engine-out is sufficient for ETOPS 180 min certification based
on current rules.)
-The GE90-110B and -115B engines (including nacelle) fitted on the
777-200LR and -300ER have a diameter larger than that of a 737 fuselage.
-The Guinness Book of World Records recognized the -115B powering
the 777-300ER as the "World's Most Powerful Commercial Jet Engine"
with a tested thrust of 127,900 lbf (569 kN).
-The longest ETOPS-related emergency flight diversion
(192 min. under one engine power) was conducted on a United Airlines
Boeing 777-200ER carrying 255 passengers on March 17, 2003, over the
southern Pacific ocean.
The 777 has substantial non-US designed or non-US manufactured content
exceeded only by the 787. The following companies have made contributions:
Mitsubishi Heavy Industries (fuselage panels), Kawasaki Heavy Industries
(fuselage panels), Fuji Heavy Industries, Ltd. (center wing section),
Ilyushin (jointly designed overhead baggage compartment).
The 777 has the same Section 41 as the 767. This refers to the part
of the aircraft from the very tip of the nose to just behind the cockpit windows.
From a head-on view the end of the section is very evident.
This is where the bulk of the aircraft's avionics are stored.
This article is licensed under the GNU Free Documentation License.
It uses material from the Wikipedia article "Boeing 777".
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