boeing 767

The Boeing 767 is a mid- to large-size, mid- to long-range, wide-body twin-engine jet airliner built by Boeing Commercial Airplanes. It was Boeing's first wide-body twinjet and its first airliner with a two-crew glass cockpit. The aircraft has two turbofan engines, a conventional tail, and, for reduced aerodynamic drag, a supercritical wingdesign. Designed as a smaller wide-body airliner than earlier aircraft such as the 747, the 767 has seating capacity for 181 to 375 people, and a design range of 3,850 to 6,385 nautical miles (7,130 to 11,825 km), depending on variant. Development of the 767 occurred in tandem with a narrow-body twinjet, the 757, resulting in shared design features which allow pilots to obtain a common type rating to operate both aircraft.

The 767 is produced in three fuselage lengths. The original 767-200 entered service in 1982, followed by the 767-300 in 1986 and the 767-400ER, an extended-range (ER) variant, in 2000. The extended-range 767-200ER and 767-300ER models entered service in 1984 and 1988, respectively, while a production freighter version, the 767-300F, debuted in 1995. Conversion programs have modified passenger 767-200 and 767-300 series aircraft for cargo use, while military derivatives include the E-767 surveillance aircraft, the KC-767 and KC-46 aerial tankers, and VIP transports. Engines featured on the 767 include the General Electric CF6, Pratt & Whitney JT9D and PW4000, and Rolls-Royce RB211 turbofans.

United Airlines first placed the 767 in commercial service in 1982. The aircraft was initially flown on domestic and transcontinental routes, during which it demonstrated the reliability of its twinjet design. In 1985, the 767 became the first twin-engined airliner to receive regulatory approval for extended overseas flights. The aircraft was then used to expand non-stop service on medium- to long-haul intercontinental routes. In 1986, Boeing initiated studies for a higher-capacity 767, ultimately leading to the development of the 777, a larger wide-body twinjet. In the 1990s, the 767 became the most frequently used airliner for transatlantic flights between North America and Europe.

The 767 is the first twinjet wide-body type to reach 1,000 aircraft delivered. As of September 2017, Boeing has received 1,204 orders for the 767 from 74 customers; 1,103 have been delivered.[1] A total of 742 of these aircraft were in service in July 2016; the most popular variant is the 767-300ER, with 583 delivered; Delta Air Lines is the largest operator, with 91 aircraft. Competitors have included the Airbus A300, A310, and A330-200, while a successor, the 787 Dreamliner, entered service in October 2011. Despite this, the 767 still remains in production.

The 767 entered service with United Airlines on September 8, 1982.[37] The aircraft's first commercial flight used a JT9D-powered 767-200 on the Chicago-to-Denver route.[37] The CF6-powered 767-200 commenced service three months later with Delta Air Lines.[3] Upon delivery, early 767s were mainly deployed on domestic routes, including US transcontinental services.[38] American Airlines and TWA began flying the 767-200 in late 1982, while Air Canada, China Airlines, and El Al began operating the aircraft in 1983.[39] The aircraft's introduction was relatively smooth, with few operational glitches and greater dispatch reliability than prior jetliners.[40] In its first year, the 767 logged a 96.1 percent dispatch rate, which exceeded the industry average for new aircraft.[40] Operators reported generally favorable ratings for the twinjet's sound levels, interior comfort, and economic performance.[40] Resolved issues were minor and included the recalibration of a leading edge sensor to prevent false readings, the replacement of an evacuation slide latch, and the repair of a tailplane pivot to match production specifications.[40]

Seeking to capitalize on its new wide-body's potential for growth, Boeing offered an extended-range model, the 767-200ER, in its first year of service.[41] Ethiopian Airlines placed the first order for the type in December 1982.[41][42] Featuring increased gross weight and greater fuel capacity, the extended-range model could carry heavier payloads at distances up to 6,385 nautical miles (11,825 km),[43] and was targeted at overseas customers.[9] The 767-200ER entered service with El Al Airline on March 27, 1984.[42] The type was mainly ordered by international airlines operating medium-traffic, long-distance flights.[9]

In the mid-1980s, the 767 spearheaded the growth of twinjet flights across the northern Atlantic under extended-range twin-engine operational performance standards (ETOPS) regulations, the FAA's safety rules governing transoceanic flights by aircraft with two engines.[41] Before the 767, overwater flight paths of twinjets could be no more than 90 minutes away from diversion airports.[44] In May 1985, the FAA granted its first approval for 120-minute ETOPS flights to 767 operators, on an individual airline basis starting with TWA, provided that the operator met flight safety criteria.[44] This allowed the aircraft to fly overseas routes at up to two hours' distance from land.[44] The larger safety margins were permitted because of the improved reliability demonstrated by the twinjet and its turbofan engines.[44] The FAA lengthened the ETOPS time to 180 minutes for CF6-powered 767s in 1989, making the type the first to be certified under the longer duration,[38] and all available engines received approval by 1993.[45] Regulatory approval spurred the expansion of transoceanic 767 flights and boosted the aircraft's sales.[41][46]

As of May 2017, the Boeing 767 has been in 45 aviation occurrences,[170] including 16 hull-loss accidents.[171] Six fatal crashes, including three hijackings, have resulted in a total of 851 occupant fatalities.[171][172] The airliner's first fatal crash, Lauda Air Flight 004, occurred near Bangkok on May 26, 1991, following the in-flight deployment of the left engine thrust reverser on a 767-300ER; none of the 223 aboard survived; as a result of this accident all 767 thrust reversers were deactivated until a redesign was implemented.[173] Investigators determined that an electronically controlled valve, common to late-model Boeing aircraft, was to blame.[174] A new locking device was installed on all affected jetliners, including 767s.[175] On October 31, 1999, EgyptAir Flight 990, a 767-300ER, crashed off Nantucket Island, Massachusetts, in international waters killing all 217 people on board.[176] The US National Transportation Safety Board (NTSB) determined the probable cause to be due to a deliberate action by the first officer; Egypt disputed this conclusion.[177] On April 15, 2002, Air China Flight 129, a 767-200ER, crashed into a hill amid inclement weather while trying to land at Gimhae International Airport in Busan, South Korea. The crash resulted in the death of 129 of the 166 people on board, and the cause was attributed to pilot error.[178]

An early 767 incident was survived by all on board. On July 23, 1983, Air Canada Flight 143, a 767-200, ran out of fuel in-flight and had to glide with both engines out for almost 43 nautical miles (80 km) to an emergency landing at Gimli, Manitoba. The pilots used the aircraft's ram air turbine to power the hydraulic systems for aerodynamic control. There were no fatalities and only minor injuries. This aircraft was nicknamed "Gimli Glider" after its landing site. The aircraft, registered C-GAUN, continued flying for Air Canada until its retirement in January 2008.[179]

The 767 has been involved in six hijackings, three resulting in loss of life,[170] for a combined total of 282 occupant fatalities.[172] On November 23, 1996, Ethiopian Airlines Flight 961, a 767-200ER, was hijacked and crash-landed in the Indian Ocean near the Comoros Islands after running out of fuel, killing 125 out of the 175 persons on board;[180] survivors have been rare among instances of land-based aircraft ditching on water.[181][182] Two 767s were involved in the September 11 attacks on the World Trade Center in 2001, resulting in the collapse of its two main towers. American Airlines Flight 11, a 767-200ER, crashed into the North Tower, killing all 92 people on board, and United Airlines Flight 175, a 767-200, crashed into the South Tower, with the death of all 65 on board. In addition, more than 2,600 people were killed in the towers or on the ground.[183] A foiled 2001 shoe bomb plot involving an American Airlines 767-300ER resulted in passengers being required to remove their shoes for scanning at US security checkpoints.[184][185]

On November 1, 2011, LOT Polish Airlines Flight 16, a 767-300ER, safely landed at Warsaw Frederic Chopin Airport in Warsaw, Poland after a mechanical failure of the landing gear forced an emergency landing with the landing gear up. There were no injuries, but the aircraft involved was damaged and subsequently written off.[186][187][188] At the time of the incident, aviation analysts speculated that it may have been the first instance of a complete landing gear failure in the 767's service history.[189] Subsequent investigation determined that while a damaged hose had disabled the aircraft's primary landing gear extension system, an otherwise functional backup system was inoperative due to an accidentally deactivated circuit breaker.[187][188]

In January 2014, the US Federal Aviation Administration issued a directive that ordered inspections of the elevators on more than 400 767s beginning in March 2014; the focus is on fasteners and other parts that can fail and cause the elevators to jam. The issue was first identified in 2000 and has been the subject of several Boeing service bulletins. The inspections and repairs are required to be completed within six years.[190] The aircraft has also had multiple occurrences of "uncommanded escape slide inflation" during maintenance or operations,[191] and during flight.[192][193] In late 2015, the FAA issued a preliminary directive to address the issue.[194]

On October 28, 2016, American Airlines Flight 383, a 767-300ER with 161 passengers and 9 crew members, aborted takeoff at Chicago O'Hare Airport following an uncontained failure of the right GE CF6-80C2 engine.[195] The engine failure, which hurled fragments over a considerable distance, caused a fuel leak resulting in a fire under the right wing.[196] Fire and smoke entered the cabin. All passengers and crew evacuated the aircraft, with 20 passengers and one flight attendant sustaining minor injuries using the evacuation slides.[197][198]