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| Boeing 767 |
The Boeing 767 is a mid-size wide-body twin-engine airliner produced by Boeing Commercial Airplanes. Boeing 767 versions have a range of 5,200 to 6,590 nautical miles (9,400 to 12,200 km), and can carry between 181 and 375 passengers, depending on seating arrangement. The first wide-body twinjet produced by Boeing, the 767 was conceived and designed in tandem with the narrow-body Boeing 757 twinjet. The airliners share design features and flight decks, enabling pilots to obtain a common type rating to operate the two aircraft.
The 767 was also the first Boeing wide-body airliner with a two-person flight deck, eliminating the need for a flight engineer. The airliner has been produced in three fuselage lengths. The original 767-200 entered airline service in 1982, followed by the 767-300 in 1986, and the 767-400ER in 2000. The 767-200ER and 767-300ER have added payload and range. The 767-300F, a production freighter version, entered service in 1995.
Following in-service indications of its twinjet design reliability, the 767 received regulatory approval allowing extended transoceanic operations beginning in 1985. The aircraft is regarded as an ETOPS pioneer, being the first to receive 180-minute approval by the Federal Aviation Administration (FAA). Through the 1990s, the Boeing 767 became commonly operated on medium- to long-haul routes, and the aircraft has ranked as the most widely used airliner for transatlantic flights between the United States and Europe. There have been over 1,000 Boeing 767s ordered with over 990 delivered by early 2011. The 1,000th airframe was rolled out in February 2011, making the 767 only the second wide-body (after the Boeing 747) to have exceeded the 1,000 unit mark. The -300/-300ER models are the most popular variants, accounting for about two-thirds of all 767s ordered. In July 2010, 863 767s were in service with more than 40 airlines.
Development
In 1972, following the introduction of the first generation Boeing 747, Douglas DC-10, and the Lockheed L-1011 TriStar wide-body airliners into passenger service, Boeing embarked on parallel development studies for two new airliners. Code-named 7X7 and 7N7, these studies aimed to take advantage of new materials and propulsion advances in the civil aerospace industry. The 7N7, which developed into the Boeing 757, was conceived as a narrow-body twinjet replacement for the Boeing 727. The 7X7 was intended to be a mid-size wide-body airliner slotted between the Boeing 707 and Douglas DC-10. With aging fleets of 707s needing replacement, the 7X7 would slot between the Boeing's narrow-body jetliners and the 747. Initially, the 7X7 studies focused on a trijet design, with possible configurations including overwing engines, a T-tail, and others. In 1976, a twinjet wide-body layout, similar to the earlier Airbus A300B, became the preferred configuration, reflecting increased industry confidence in the reliability and economics of new generation turbofan engines. Airlines remained ambiguous in their requirements for the aircraft, which was roughly focused on the medium-haul, high-density market. High-density routes in the U.S. domestic market, a role targeted for the 7X7, involved the transport of large numbers of passengers between major cities.
On January 5, 1978, Boeing announced a major extension of its Everett production site, then dedicated to 747 manufacture, to accommodate its new mid-size wide-body family. That year, Boeing formally designated its new wide-body airliner as the 767, and the company planned to offer three variants: a 767-100 with 180 seats, a larger 767-200 with 210 seats, and a trijet 767MR/LR version with 200 seats intended for intercontinental routes. The 767MR/LR was eventually dropped in favor of standardizing around the twinjet configuration, and the 767-100 was ultimately not offered for sale, as its capacity was too close to the 757's. On July 14, 1978, the Boeing 767 was officially launched by United Airlines, which placed an order for 30 767-200s, followed later that year with orders from American Airlines and Delta Air Lines.
Production and service
Construction of the prototype Boeing 767, a -200 variant, began on July 6, 1979. Despite Boeing's two-person digital cockpit design, United Airlines initially demanded a conventional three-person crew with two pilots and a flight engineer. United's position was due to concerns about the risks associated with introducing a new aircraft. Boeing tried to convince United and others to adopt its new cockpit design with data from the two-person crew Boeing 737. In 1981, a U.S. Presidential task force studied the safety of operations with two crew on wide-body aircraft, and compared its capabilities to three-person configurations. The task force determined that a crew of two was safe for flight in July 1981, which paved the way for acceptance of the 767's two-person flight deck. One airline, Ansett Australia, ordered 767-200s with a three-person flight deck, due to union demands. These were the only 767s fitted as such.
The first 767, registered N767BA and equipped with Pratt & Whitney JT9D turbofans, rolled out on August 4, 1981. The aircraft took its maiden flight on September 26, 1981. Enlisted for the 767 flight test program, the first four aircraft built were equipped with JT9D engines, while the fifth and sixth aircraft were fitted with General Electric CF6-80A turbofans. The sixth airframe was used in route-proving flights. Following the successful completion of flight testing, the JT9D-powered 767-200 received Federal Aviation Administration (FAA) certification on July 30, 1982. The first 767 with a two-person flight deck completed its maiden flight on May 27, 1982. The CF6-80A-powered 767-200 was certified by the FAA on September 30, 1982.
Following the first delivery to United Airlines in August 1982, the 767-200 entered airliner service on September 8, 1982, with its first flight from Chicago to Denver. Delta Air Lines commenced service with the CF6-powered 767-200 on December 15 of the same year. Deliveries to mainline U.S. carriers American and TWA followed. The 767's service introduction was relatively smooth, with few technical issues, and greater operational reliability than prior aircraft. The 767 received early international orders from Air Canada, All Nippon Airways, Ansett Australia, Britannia Airways, Egyptair, El Al, Ethiopian Airlines, and Transbrasil. The 767 was approved for U.S. CAT IIIb instrument landing operation in March 1984. This revision permitted operations with minimums as low as RVR 300 (Runway Visual Range 300 meters). The 767 was the first aircraft certificated for CAT IIIb by the FAA.
A key issue in early Boeing 767 operations was proving the aircraft's reliability for overseas operations. Prior to the 767, the FAA restricted twin-engine aircraft to over-water flights of 90 minutes or less distance from diversion airports. In June 1985, the FAA granted approval for 120-minute Extended-range Twin-engine Operational Performance Standards (ETOPS) to 767 operators, on an individual airline basis, provided the operator met flight safety standards. The increased safety margin changes were permitted due to the improved reliability demonstrated by the 767's turbofan engines. The FAA lengthened the ETOPS time to 180 minutes for GE-powered 767s in 1989, making the twinjet the first aircraft to be certified under the longer duration. Approvals for the other 767 engines were obtained by 1993. ETOPS allowed for much expansion of transatlantic flights by twin-engine airliners.
Interior
The 767 features a twin-aisle cabin with a typical configuration of 2–3–2 in economy class and 2–2–2 in business class. In the 2–3–2 layout, every passenger is no more than one seat from the aisle, allowing for faster entry/exit and meal service. This seven-abreast layout also places 87% of all seats at a window or aisle, accommodating passenger requests, and the seat-to-aisle ratio of 3.5 seats is less than other jetliners' four to six economy seats per aisle. On the 767 it is possible to squeeze an extra seat for a 2–4–2 configuration, however this seating is cramped and therefore uncommon.
At its debut, the 767 cabin incorporated new design features intended to enhance on-board convenience. The overhead bins were larger than on previous aircraft, sized to accommodate garment bags without folding, and strengthened for heavier carry-on items. More lavatories per passenger were offered than previous models, including in the center cabin, in consideration of an estimated four-hour average flight time for early 767s. A single large economy galley was installed near the aft doors on both the 767 and 757, allowing for faster meal service and ground loading.
Newer 767-200s and 767-300s, as well as all 767-400ERs, feature a 777-style cabin interior, known as the Boeing Signature Interior. Launched on the 767-400ER, this interior features even larger overhead bins, indirect lighting, and sculpted panels. The 767-400ER also is equipped with larger windows exactly like those found on the 777. All new 767s built feature the Signature Interior, and it is available as a retrofit for older 767s. In addition to the Signature Interior retrofit option, a simpler modification known as the Boeing 767 Enhanced Interior is available. This retrofit borrows styling elements from the Boeing Signature Interior, with curved ceiling panels and indirect lighting, but only minimally modifies existing overhead bins and cabin architecture.