|
Boeing 777-200 of Brazilian airline Varig. |
The Boeing 777 is a family of long-range widebody twin-engine airliners built by Boeing Commercial Aircraft Corp. It carries between 305 to 550 passengers and has a range spanning from 5,600 to 8,870 nautical miles.
The Boeing 777-200 photo seen here was landing at London (Heathrow) Airport in August 2002. Distinguishing features of the 777 can be seen, including the set of six wheels on each main landing gear, and the blade-like rear tailcone.
In the 1970's Boeing unveiled its new models to replace and expand its then current line-up. They are the twin-engined 757, to replace the venerable 727; the twin-engined 767 to challenge the Airbus A300 and the 777 trijet to compete with DC-10 and Lockheed Tristar.
It was basically a tri-jet airplane based on a re-winged 767 design, and it had two main variants; a transcontinental airplane transporting 175 on trips up
to 5,000km (2,700nm) as well as an intercontinental version capable of flying over 8,000km (4,320nm) with the same passenger load.
The twinjets were launched and the 777 trijet was cancelled. The success of the the 757 and 767, particularly with the benefit of ETOPS regulations of the 1980's, and the design complexity of a trijet plus the absence of an engine with thrust in the range of 40,000lb confirmed the choice made by Boeing.
But Boeing have a big gap in its product line in-between the 767-300ER and the 747 family.It also realized the potential of such an airplane in-between the 767-300ER and 747-400 in terms of size and range. The DC-10 and Lockheed Tristar, being of 1960's design is also ripe for replacement. Airbus, in mean time developed the A330 and A340 to fulfill that requirement.
Initial proposal from Boeing was just to enlarge the 767, resulting in the 767-X concept. It was basically a 767 with longer fuselage and bigger wings seating about 340 passengers and with maximum range of 7,300 nautical mile. The airlines were unimpressed.
They wanted from short to intercontinental range capability, cabin cross-section similiar to 747,fully flexible cabin configuration and operating cost better than any 767 stretch. The result is a totally a new design, the 777 twinjet.
To satisfy the demanding airline requirements, a lot of new technology new to Boeing (most of it was already in service in Airbuses) has to be employed. Features such as
The initial model 777.First customer delivery was to United Airlines in May 1995. It is available with maximum take-off weight (MTOW) from 229 to 247 tonnes and range capability between 3780 to 5150 nautical mile.
The basic 777-200 is powered by two 74,000lb Pratt & Whitney PW4074 turbofans, or 75,000lb General Electric GE90-75Bs, or 75,000lb Rolls-Royce Trent 875s.
The increased weight longer range 777-200ER features additional fuel capacity, with increased MTOW range from 263 to 286 tonnes and range capability between 6000 to 7700 nautical miles. The first 777-200ER was delivered to British Airways in February 1997.
The 777-200ER is powered by two 84,000lb PW4084s, or 85,000lb GE90-85Bs, or 84,000lb Trent 884s; or 90,000lb class PW4090s, GE90-90B1s, or Trent 890s; or 92,000lbGE90-92Bs.
On April 2, 1997 a Boeing 777-200ER, tail registration 9M-MRA (dubbed the 'Super Ranger') of the 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 20044.20 km in 21 hours, 23 minutes.
Boeing claims the 777-200LR will be the longest ranging airliner, capable of flying 8865nm or 18 hours flying time. It will achieve this with gigantic 110,000lb thrust GE90-110B1 turbofans, a significantly increased MTOW and optional auxiliary fuel tanks in the rear cargo hold. Other changes include raked wingtips, new main landing gear and additional structural strengthening.
The stretched 777-300 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 features 40% lower maintenance costs.
It features a 33ft 3in 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 -300 has a tailskid and ground manoeuvring cameras mounted on the horizontal tail and underneath the forward fuselage to help pilots during taxi due to its enormous lenght.
It was awarded type certification simultaneously from the US FAA and European JAA and was granted 180min ETOPS approval on May 4 1998 and entered service with Cathay Pacific later in that month.
Typical range with 386 three class passengers is 5720 nautical mile.It is powered by either two 90,000lb Pratt & Whitney PW-4090 turbofans, or 98,000lb PW-4098s, or 92,000lb Rolls-Royce Trent 892s, or 92,000lb General Electric GE90-92Bs.
This is the long range version of 777-300 is designed as a replacement for 747-400s. Boeing is targeting the 747 more as freighters.
More powerful General Electric GE90-115B engines (currently the world's most powerful jet engine at 115,300lb thrust), raked wingtips, strengthened body, wings, empennage, nose gear, engine struts and nacelles, new main landing gear, and extra fuel tanks are the modifications embodied in the 777-300ER.The range with 365 passengers, is increased up to 7,250 nautical mile.The -300ER programme is launched by Air France.
Early History
Technological features
The 777 first flew on June 14, 1994 and underwent a flight-test programme mor extensive than any other Boeing models. Boeing pioneered the Early ETOPS process giving the 777 180-min ETOPS rating entry into service. The FAA awarded full 180 minutes ETOPS clearance for PW4074 777-200s on May 30, 1995.Variants
777-200 series
777-200ER series
777-200LR Series
777-300 Series
777-300ER Series
General Characteristics
Some Boeing 777 facts
External links