Boeing 777 (Triple Seven)
Wide-Body Passenger / Cargo Jet Airliner
The 777 wide-body has been a successful commercial addition for the Boeing Company.
Authored By: Staff Writer | Last Edited:
Throughout the 1970s, the Boeing Company operated the mammoth 747 four-engined, "wide-body" long-range jet airliner. In 1978, a move was enacted to supplement the 747 with the "narrow-body" 757 series, the wide-body 767 series and the Trijet 777, a triple-engine aircraft - a design proving popular at the time. The 757 and 767 both excelled in their operational service lives while the Trijet 777 fell out of favor. In an effort to fill the void left by the Trijet 777, the company moved on a new endeavor which saw it modify its existing 767 design. When potential carriers appeared lukewarm to the 767 modifications (designated as "767-X"), Boeing ordered an all-new design which would evolve to become the twin-engine, wide-body 777 family line. The Boeing 777 was developed completely from computer-aided designs, marking it as the first commercial aircraft to be devised as such. It also became Boeing's first "fly-by-wire" digitally-assisted airliner in the history of the company. In addition, feedback was taken from eight major carriers to include "power players" American Airlines, British Airways, Cathay Pacific Airways, Delta, Japan Airlines, Qantas, United Airlines and All Nippon Airways.
Despite the involvement of so many companies, the 777 went on to become a commercial success for Boeing. Production of the series was underway in 1993 with a first flight recorded on June 12th, 1994. The first 777 customer became United Airlines in October of 1990. Formal entry into service occurred with United Airlines on May 15th, 1995 with official introduction coming on June 7th. The first commercial flight was recorded on June 7th, 1995 from London to Washington, D.C. Production has since surpassed 1,360 units and is still ongoing as of this writing (2012). Dispatch reliability (noted as high as 99.3%) and economical qualities have proven a major selling point with carriers concerning the 777 family. All passenger-minded versions of the aircraft can be arranged in the typical "three-class" seating configuration as needed and offer amenities consistent with expanding technologies such as personal power ports, in-flight entertainment as well as the latest in on-demand features. Since June of 1995, the 777 family line of aircraft has completed 5 million flights totaling 18 million hours of flight time. The 777 series set a world air distance record for non-stop travel by a commercial jet-powered aircraft when it completed a 11,664nm journey from Hong Kong to London over November 9th to the 10th in 2005. The journey spanned nearly 23 hours.
Design of the Boeing 777 model series is typical of passenger jet airliners to date. The type is characterized by its tubular fuselage which contains the passenger/cargo hold as well as the cockpit. The cockpit is situated at the extreme front end of the aircraft with six window panels offering excellent views out of the cockpit. The aircraft is primarily crewed by two pilots, each situated behind an all-glass cockpit with windowed views over the nose. This crew is supplemented by cabin crew in passenger airliner models as needed. The aircraft makes use of a low-set monoplane wing arrangement held at amidships and these installations sport noticeable sweep along the their leading edge. The trailing edges feature a straight section at the wing root which then sweeps back when tapering to the wing tip. Three strakes are noted along each wing underside as are speed flaps and ailerons, the latter held well outboard. Each wing also supports an engine nacelle, these engine fittings being some of the largest in commercial use today - the engine intake can easily fit a standing man, showcasing just how massive these installations truly are. In addition to the engines, the wings also house the large main landing gear legs, each showcasing six tires - an identifying feature of the series. The nose landing gear leg is of a typical dual-wheel configuration and is located under and aft of the cockpit floor. The empennage of the aircraft is conventional, with a single vertical tail fin clipped at its tip and a pair of horizontal tailplanes, also clipped at the tips. The tailplanes are set along the extreme aft portion of the fuselage sides with the fuselage then tapering into a "blade-type" cap at the extreme end. Overall, the 777 is composed of 3 million individual parts provided by some 500 global contractors making for one complex piece of aerial machinery.
Flight control for the 777 series in handled by a full digital "fly-by-wire" system, technology once belonging solely to high-end military fighter aircraft. In this system, electrical signals are sent from the pilot controls (column, foot pedals, etc...) to a central processing computer which then dictates to the various control surfaces of the aircraft as needed. This negates the use of cables and applicable wiring to achieve the same result, thusly simplifying construction and actuation. The cockpit consists of five large, full-color liquid crystal displays (LCDs) that relay pertinent flight information to both pilots. The pilots are seated in a side-by-side arrangement with equal access to all controls. The throttle is managed from a center console separating the two seats. This console forces the pilots to climb up and over when entering or exiting their respective seats. Additional controls are located ahead and above each seat position. Views from each seat are elevated, providing for a commanding view of the area ahead, to the sides and to each engine as needed. The six windowed panels converge at centerline and are heavily framed.
The Boeing 777 has since been introduced in a variety of fuselage lengths and operational ranges beginning with the base 777-200. The 777-200 was brought about as a domestic-minded hauler with a 5,235nm range and seating for 250 to 440 passengers. The 777-200ER ("Extended Range") derivative increased both the maximum take-off weight and internal fuel stores to allow for traveling out to 7,700nm. The 777-200LR ("Longer Range") derivative was introduced as a long-range commercial airliner in 2006. The aircraft's maximum take-off weight was increased as was fuel capacity while the internal structure was reinforced throughout.
The 777-300 was introduced in 1998 as a "stretched" variant of the base 777-200 featuring an elongated fuselage (up 242 feet from 209 feet). This allowed for passenger seating to range from 365 to 550 persons as well as greater fuel and cargo stores within. The 777-300ER ("Extended Range") derivative increased range through additional internal fuel stores while the internals were reinforced as well.
The 777 has also been developed into a passenger-less cargo transport known simply as the 777F ("Freighter"). The type is based on the 777-200LR production model with all of its inherent range and hauling benefits (out to 4,900nm with a 37 pallet load limit). A 777 BCF ("Boeing Converted Freighter") is in the works, this based on the 777-200ER production model. At one point, Boeing offered the 777 as a possible replacement for the United States Air Force's KC-767 - this based on the Boeing 767 line - intended to take on the same role as the KC-767 in-flight refueler. However, the proposal eventually went with the 767 model instead to which the aircraft will be known as the "KC-46A" in USAF nomenclature. 18 of this type are expected delivered by 2017.
All 777 models are cleared for operational altitudes of 43,100 feet. Maximum ranges vary between the available models and range between 5,240nm, 7,725nm, 9,380nm, 4,900nm, 6,005nm and 7,930nm in the 777-200, 777-200ER, 777-200LR, 777F (cargo), 777-300 and 777-300ER respectively.
The 777-200 has utilized the Pratt & Whitney PW4077, Rolls-Royce 877 and General Electric GE90-77B series engines providing for 77,000lbf, 76,000lbf and 77,000lbf lbs of thrust respectively. The 777-200ER has made use of the Pratt & Whitney PW4090, the Rolls-Royce 895 and General Electric GE90-94B series engines providing for 90,000lbf, 93,400lbf and 93,700lbf lbs of thrust respectively. The 777-200LR and 777F cargo models have shared the General Electric GE90-110B1 and GE90-115B1 series engines for an output of 110,000lbf and 115,540lbf respectively. The 777-300 is fitted with Pratt & Whitney PW4098, Rolls-Royce 892 and General Electric GE90-92B and GE90-94B engines of 98,000lbf, 93,400lbf, 92,000lbf and 93,700lbf respectively. The 777-300ER is delivered with the General Electric GE90-115B1 series engines of 115,540lbf output.
Up until July 6th, 2013, the Boeing 777 series had not experienced any fatal loss of passenger or crew during its 18+ years of operation. However, the unblemished record changed when Asiana Airline Flight 214 originating from Seoul, South Korea, crashed in an attempted landing at San Francisco International in California. Two students were killed in the incident while 182 of the 305 aboard suffered varying degrees of injury (some facing paralysis and other spine-related trauma). Other major issues prior to the crash proved to be ice crystal formations occurring in the engines, clogging the fuel-oil heat exchanger. This was the cause of a crash landing at Heathrow Airport in 2008 when 47 injuries were reported. The fuel-oil heat exchangers have since been reengineered by order of accident investigators and business for the 777 has returned to normal since.
The upcoming Boeing 787 "Dreamliner" shares much of the design lessons and learned - as well as features - inherent in the 777 series line.