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By the late 1980's Boeing
realised that it needed an aircraft to fill the gap between the 767-300
and 747-400. Capacity was to be between 375 and 400 in a two-class layout
or up to 440 in a one-class layout. Boeing no longer had the entire share
of the market. Airbus was launching its A330/A340 aircraft family,
McDonnell Douglas had the DC-10 and Lockheed had the L-1011 TriStar. Originally
dubbed as the 767-X, the 777 was a completely new aircraft. The design
teams worked closely with the airlines to give them a aircraft that they
wanted. This ensured that all parties agreed on specifications and
therefore the finished product would satisfy all parties. In October 1990,
United Airlines placed an order for up to 68 aircraft (34 firm & 34
options) and thus gave the 777 project the go-ahead. The wings of the 777
were designed to be the most aerodynamically efficient wings ever
developed for a subsonic commercial aircraft. The new wings were designed
to provide good climb performance as well as high-level cruise. Boeing's
new aircraft was designed to be for two-man operation and as simple and
easy to use as possible. The new cockpit featured six LCD screens to
present the data to the crew. The 777 was also the first Boeing aircraft
to feature a three axis fly-by-wire system. Engines for the 777 were made
available from all three major manufacturers, the Pratt and Whitney
PW4084, the Rolls Royce Trent 895 and the General Electric GE90. The
Boeing 777 required an enormous amount of electricity. This was partly due
to the new passenger entertainment system installed in every seat on the
aircraft. To solve this problem Boeing installed three 120kVa generators
in the aircraft. The Boeing 777 was designed with a computer aided design
(CAD) system. The CAD system eliminated the need for Boeing to construct
expensive full-size mock-up's of the aircraft. The first Boeing 777
(N7771) was rolled out at Everett on April 9, 1994 and made its first
flight on June 12, 1994. The first aircraft made over 300 test flights. As
the test programme progressed, nine aircraft were allocated to flight
testing, three for each engine type. During the flight test programme,
from June 1994 to March 1996, the nine aircraft accumulated almost 7,000
flying hours, including time to qualify for ETOPS. United Airlines took
delivery of their first aircraft (N777UA) on May 15, 1995. The airline
flew its first revenue-earning 777 flight on June 7 between London
Heathrow and Washington Dulles. As orders for the basic 777 continued to
grow, Boeing was already working on the first 777 variant, the 777-200IGW
(or 777-200ER as it later became). British Airways was the launch customer
for the 777-200ER and the first aircraft was rolled out at Everett on
September 3, 1996.
Another market-driven
derivative was the Boeing 777-300. The 777-300 was designed to meet airline
demand for a replacement for early versions of the 747, but offered one
third less fuel burn and featured 40% lower maintenance costs. Seating on
the 777-300 could vary from 368 passengers in a three-class layout, to 550
passengers in a one-class, ten abreast layout. By June 1995 Boeing had
received commitments for 31 aircraft, from four airlines: ANA, Cathay
Pacific, Korean Air and Thai. Compared with the 777-200 the -300 featured a
10.13m (33ft 3in) stretch, comprising of plugs fore and aft of the wings. To
cope with the increased passenger load, the -300 featured a strengthened
undercarriage, airframe and inboard wing. An additional emergency exit was
also needed and this was fitted over the wing on each side of the aircraft.
Other changes compared with the 777-200 included the addition of a tailskid
and ground manoeuvring cameras mounted on the horizontal tail and underneath
the forward fuselage. Otherwise changes have been kept to a minimum to
maximise commonality. The first 777-300 was rolled out at Everett on August
29, 1997 and the maiden flight took place on October 24, 1997. Cathay
Pacific received its first -300 on May 22 1998.
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