Among the most successful of Boeing’s products, the Boeing 767 was the company’s first twin-engined wide-body aircraft, and would go on to be a rival with the 737 and 747 as one of the company’s most popular and loved aircraft.
In terms of wide-body aircraft, Boeing set the benchmark with the legendary 747, a double-deck, quad-engined monster that left all others in the dust. However, it was quickly noted that the Boeing 747 was not a highly flexible aircraft, being too big for many routes and airports. As such, a large number of airlines had to reorganise their existing fleets to cope, primarily the use of the previous Boeing 707. The 707, though a capable aircraft, was a comparatively small, narrow-body airliner, and on many of the busier routes would not be able to cope, airlines instead being forced to choose a more costly method of increasing frequency.
In 1972, two years after the 747 hit the skies, Boeing began considerations for the 7X7, a replacement for the 707 in a wide-body format. The intention of the 7X7 was to fill the gap between the flagship 747 and the smaller 737. In order to get the project rolling, and as a risk-sharing agreement to cover the high development costs, Boeing signed a deal with Italian corporation Aeritalia and the Civil Transport Development Corporation (CTDC), a consortium of Japanese aerospace companies, the first time in the company’s history it had involved itself with a major international joint venture. Aeritalia and the CTDC in return would receive supply contracts in return for their early participation.
Original intentions for a Short take-off and landing regional airliner were scrapped following unenthusiastic responses by customers, and thus the decision was made to create a medium-range international airliner that would go head-to-head with Europe’s rising star, the Airbus A300, another twin-engined, wide-body airliner. At this stage the proposed aircraft featured two or three engines, with possible configurations including over-wing engines and a T-tail.
By 1976, the 7X7 project had designated the aircraft a twinjet like the A300, with major focus being made on the development of highly reliable turbofan engines with greater amounts of power rather than the previous rule of three or four engines. The 7X7’s main market was for either international/transatlantic flights, but also for high-capacity domestic flights such as New York to Chicago or Los Angeles. Advancements in civil aerospace technology, including high-bypass-ratio turbofan engines, new flight deck systems, aerodynamic improvements, and lighter construction materials were to be applied to the 7X7. Many of these features were also included in a parallel development effort for a new mid-size narrow-body airliner, code-named 7N7, which would become the 757. Work on both proposals proceeded through the airline industry upturn in the late 1970s.
In 1978, Boeing made preparations for this new model by extending their gigantic Everett factory for what was now designated as the Boeing 767. The 767 would consist of three models, the -100, a high-capacity, short-range model with 190 seats; the -200, a medium range model with 210 seats; and the 767MR/LR, a trijet version with over 200 seats. Eventually, Boeing settled on only selling the -200 variant, which was launched on July 14th, 1978, with 30 orders by United Airlines, followed by 50 more 767-200 orders from American Airlines and Delta Air Lines later that year.
Design of the 767 was done based on efficiency rather than capacity. The various fuel
and energy crisis’ of the 1970’s had made airlines aware of the expense of operating inefficient aircraft, and thus the new trend of lower operating costs was established. Boeing intended for the 767 to slash inefficiency by between 20 and 30%, mainly through new engine and wing technology. The 767’s design was one of the first to be aided by computer, and over 26,000 hours of extensive wind-tunnel tests were carried out to make the aircraft as streamlined and efficient as possible. The design stage covered both the 767 and its smaller brother the 757 in order to save the need for duplicating tests. Both aircraft would ultimately receive shared design features, including avionics, flight management systems, instruments, and handling characteristics.
The 767 was also the first Boeing product that gave customers the option of engine types, the choices being of either the Pratt & Whitney JT9D or General Electric CF6. Both jet engine models had a maximum output of 48,000 pounds-force of thrust. Engines were mounted in a position similar to that of trijets, approximately one-third the length of the wing from the fuselage. The larger wings were designed using an aft-loaded shape which reduced aerodynamic drag and distributed lift more evenly across their surface span than any of the manufacturer’s previous aircraft. The wings provided higher-altitude cruise performance, added fuel capacity, and expansion room for future stretched variants. The range of the initial 767-200 was 3,850 nautical miles, making it capable of flying across the USA or across the Atlantic to Europe.
The size of the 767 filled the gap perfectly between the 747 and 707, with a width of 16.5ft, making it much more aerodynamic. The narrower bodyshape however resulted in the LD3 container units designed for the 747 and DC-10 being too large for the aircraft, thus an entirely new container, the LD2, was created instead. The adoption of a conventional tail design also allowed the rear fuselage to be tapered over a shorter section, providing for parallel aisles along the full length of the passenger cabin, and eliminating irregular seat rows toward the rear of the aircraft.
One of the most endearing features of the 767 however is its elimination of the Flight Engineer, instead developing a digital glass cockpit that could be operated by two crew members. Cathode ray tube (CRT) colour displays and new electronics replaced the role of the flight engineer by enabling the pilot and co-pilot to monitor aircraft systems directly. Despite the promise of reduced crew costs, United Airlines initially demanded a conventional three-person cockpit, citing concerns about the risks associated with
introducing a new aircraft. The carrier maintained this position until July 1981, when a U.S. presidential task force determined that a crew of two was safe for operating wide-body jets. A three-crew cockpit remained as an option and was fitted to the first production models. Ansett Australia ordered 767’s with three-crew cockpits due to union demands; it was the only airline to operate 767’s so configured. The 767’s two-crew cockpit was also applied to the 757, allowing pilots to operate both aircraft after a short conversion course, and adding incentive for airlines to purchase both types.
Production began in July 1979 at the newly opened extension of the Everett Factory, and the prototype 767, N767BA, was rolled out on August 4th, 1981. This aircraft would make its maiden flight on September 26th the same year. The only fault encountered on this flight was the inability to retract the landing gear due to a hydraulic fluid leak. By the time test flights started the 767 had amassed a huge amount of popularity and hype, with 173 firm orders from 17 customers, including Air Canada, All Nippon Airways, Britannia Airways, Transbrasil, and Trans World Airlines. The first delivery was carried out in August 1982 to launch customer United Airlines, and after fitting out, United began its 767’s in passenger operation a month later from Chicago to Denver.
Initially, the Boeing 767’s were used solely on domestic routes within the United States, and proved to be incredibly successful on such operations. As such, many airlines were quick to sell off their ageing Boeing 707’s. Within the first two years, the 767 had proven itself a massively reliable aircraft, with a 96% take-off rate without delay due to a technical fault. Soon afterwards, the 767 was considered for international services, and carriers began to place them on transatlantic services to Europe, or on high capacity seasonal services to the Caribbean.
Eager to follow up their success, Boeing announced in 1983 and 1984 the -300 and
-300ER, respectively. The -300 stretched the 767 by 21ft, increasing capacity by 20%. While the -300’s range was 4,260 miles, the -300ER’s was 5,990 miles, and could easily do the longest international routes without the need for stopovers. The -300 made its maiden flight in January 1986, being launched later that year with Japan Air Lines, whilst the -300ER made its first flight in December 1986 before entering service with American Airlines in 1988.
The final passenger variant of the 767 was the 767-400, which was announced in 1995 as another stretched version. The -400 extended the body of the aircraft by another 21ft over the -300, increasing passenger capacity from 218 to 245. The aircraft made its maiden flight in October 1999, with delivery to launch customer Delta Air Lines taking place in September 2000, this type being built specifically for replacement of their ageing L-1011 Tristars.
In addition to passenger 767’s, the aircraft has also been configured for cargo, usually in the traditional sense of having a stripped out interior and the addition of a large cargo door on the side.
The 767 has also seen multiple military variants, ranging from air-to-air tankers to AWACS radar aircraft and transport aircraft. The first military variant was the Airborne Surveillance Testbed, a modified Boeing 767 that was launched in 1984. Intended to evaluate the feasibility of using airborne optical sensors to detect and track hostile intercontinental ballistic missiles, the modified aircraft first flew on August 21st, 1987. Alterations included a large “cupola” or hump which ran along the top of the aircraft from above the cockpit to just behind the trailing edge of the wings, and a pair of ventral fins below the rear fuselage. Inside the cupola was a suite of infrared seekers used for tracking theater ballistic missile launches. Following the end of the AST program in 2002, the aircraft was retired for scrapping.
Next was the E-767, similar in design to the E-3 Sentry, was built for AWACS (Airborne Warning and Control System), and featured a large rotating Radar dome attached to the top of the aircraft. Built for the Japan Self-Defense Forces, the E-767 was developed between 1994 and 1997, with the Boeing 767-200ER bodies being built at Everett Factory before being flown to the Boeing Integrated Defense Systems plant in Wichita, Kansas. There it was modified to include structural strengthening to accommodate a dorsal surveillance radar system, engine nacelle alterations, as well as electrical and interior changes. Only four of these aircraft were built, all of which for Japan, deliveries being made by the end of 1998.
Two tanker variants have also been developed, the KC-767 Advanced Tanker and the KC-767 Tanker Transport. Development of the KC-767’s began in the late 1990’s, and tender was primarily down to international air forces such as the Italian Air Force and, again, the Japan Self-Defence Forces. The KC-767’s are capable of carrying 160,000lbs of fuel, but can also be configured to be a personnel transport and cargo plane if need be. KC-767’s have been slowly delivered since 2003, with 11 aircraft in service so far. The KC-767 has since been developed into the KC-46 Pegasus, a refuelling/transport aircraft that made its début in 2015 and will be delivered to the U.S. Air Force from 2017.
Today a majority of Boeing 767’s are still in service with major carriers, and production of the -300 and -400 variants continues to this day. As of April 2016, 1,065 of these aircraft have been produced at a cost of $185m each, though it is expected that some time in the near future, the newer Boeing 787 will come to kill off 767 production.
Sadly, the Boeing 767 has been the victim of numerous horrific crashes, being unfortunately involved in some of the worst incidents in aviation and indeed world history.
The first notable incident involving the 767 was on July 23rd, 1983, when Air Canada Flight 143 suffered fuel starvation during an internal flight from Montreal to Edmonton. The aircraft glided without power for several minutes before it was decided to land the aircraft at a redundant RCAF airbase at Gimli in rural Manitoba. The aircraft landed without any injuries incurred on the passengers or crew (though some minor injuries were received during evacuation) and the aircraft was later returned to service, the
cause being found to be that the amount of fuel that had been loaded was miscalculated because of a confusion as to the calculation of the weight of fuel using the metric system, which had recently replaced the imperial system for use with the 767.
The type’s first fatal crash however was on May 26th, 1991, when Lauda Air Flight 004 plunged from the sky shortly after takeoff from Bangkok, killing all 223 on board. An investigation headed by company owner and former F1 racing driver Niki Lauda found the cause to be due to a computer error activating the port side reverse thruster in-flight, essentially bringing the plane to a stop on the left hand side.
On October 31st, 1999, another notable crash occurred when EgyptAir Flight 990 dived into the Atlantic Ocean off Nantucket Island, Massachusetts, killing all 217 aboard. The cause of the crash is disputed, but most believe that it was an apparent suicide by the co-pilot.
Aside from these incidents, the Boeing 767 has been hijacked six times, resulting in three fatal crashes. The first fatal hijacking was Ethiopian Airlines Flight 961 on November 23rd, 1996. While operating a short hop from Addis Ababa to Nairobi, three hijackers stormed the cockpit and demanded to be flown to Australia. With not enough fuel and unable to reason with the hijackers, the Captain flew the plane to the Comoros Islands and hoped to make a landing at the airport there once the fuel had been exhausted. However, after an altercation with the hijackers, he lost his bearings and was forced to ditch in the Indian Ocean just off the beach. During the crash landing, the port side engine slowed the aircraft’s left hand side too fast and caused it to flip over, breaking up into several pieces that sank quickly, the spectacular crash caught on film by a tourist on the beach. The crash and subsequent sinking claimed the lives of 125 out of the 175 passengers, mostly due to people inflating their life jackets while still inside the plane.
However, the most notable crash and hijacking incident involving the Boeing 767 was on September 11th, 2001, when American Airlines Flight 11 and United Airlines Flight 175, both internal flights from Boston to Los Angeles, were hijacked by Islamic extremists and flown deliberately into the Twin Towers of the World Trade Center. Flight 11 struck first at 08:46am between the 93rd and 98th floors of the North Tower, killing untold numbers of unsuspecting people on those floors. Flight 175 flew 17 minutes later into the 78th to
81st floors of the South Tower, killing an estimated 300 people who were attempting to make their way out of the tower. The horrific damage to the structure, compounded by a vigorous fire, caused both 1,350ft towers to crumble within two hours of the impacts, the South Tower collapsing at 09:59am, and the North Tower at 10:28am. More than 2,600 people died at the World Trade Center that day, making it the worst aviation related incident. United 175’s final plunge into the South Tower became one of the most defining moments in world history, and an immediate icon of pure evil at its most wicked.
Today, around 750 Boeing 767’s remain in revenue earning service with many major airlines, and, as mentioned, these aircraft continue to be produced. 767-200’s are however very rare aircraft these days, with a majority of them retired by the mid-2000’s by major carriers. Some of the -200’s however have been preserved, including the first aircraft to operate with Delta Air Lines, N102DA, which now resides at the Delta Air Lines Air Transport Heritage Museum in Atlanta. A set of cockpits from ex-American Airlines examples were salvaged for use in films and movies as props, whilst an ex-Transaero unit was floated on a barge to Enniscrone in Ireland to be used as part of a new Glamping site.
Earlier versions of the -300’s and -300ER’s are also hard to come by, though some -300’s that date back to the late-1980’s can still be found at work for major carriers such as United and American Airlines. Today, modern -300’s and -400’s are now in abundance with both passenger and cargo carriers, and the legacy of this iconic and beautiful aircraft shows no sign of letting up. Perhaps not as famous as the 747, but certainly just as vital!