Boeing 777 787

Boeing Commercial Airplanes president Alan Mulally, who had previously served as general manager of the 777 program, contrasted the difference in the approval process by the board between the 777 and 787 saying “In the old days, you would go to the board and ask for X amount of money, and they'd counter with Y amount of money, and then you'd. Boeing 787 Composites. Weight is being reduced by the fact that up to 50% of the aircraft is built using composite materials, including the fuselage and wings. To put this in perspective, compare the Boeing 787 with Boeing’s top-selling Aircraft, the Boeing 777.

v1.2.0 / 01 nov 20 / greg goebel

* Following the success of the 707, 727, 737, and 747 jetliners, the Boeing company began investigation of a new generation of aircraft, one result being a large twinjet, the '767', which led in turn to the scaled-up '777'. Both these big jetliners proved successful, with the 767 featuring a number of military derivatives, and in the 21st century they are being followed by a new generation twinjet, the '787'. This document provides a history and description of the 767, 777, and 787 jetliners.

[1] BOEING 767 ORIGINS
[2] 767 DETAILS & VARIANTS
[3] MILITARY 767S
[4] BOEING 777
[5] BOEING 787
[6] COMMENTS, SOURCES, & REVISION HISTORY

[1] BOEING 767 ORIGINS

* In the 1970s, jetliner manufacturers introduced 'wide-body' airliners that could haul larger numbers of passengers, Boeing being very successful with their 747 jumbo jet. Boeing management began to think there was a market for a smaller wide-body, focused on the transcontinental market. The expected retirement in the 1980s of Boeing 707 and Douglas DC-8 jetliners enhanced that sense of opportunity; the jetliners established in the 1960s were not only aging, the tougher environmental regulations and the high fuel prices of the energy crisis due to the 1973:74 Arab oil embargo made cleaner and more efficient airliners attractive.

Boeing initiated a '7X7' program to develop the new wide-body. By 1976, the 7X7 had congealed into a twin-aisle aircraft with three jets and a tee tail, something like a scaled-up Boeing 727. Availability of sufficiently powerful turbofan engines reduced the number of engines to two; the tee tail lingered somewhat longer, but was ultimately replaced by a conventional swept tail arrangement with a low-mounted tailplane, that seen as having better stall characteristics. Passenger capacity was envisioned as 180 to 200 seats.

In early 1978, Boeing began to peddle the '767' to prospective customers, with United Airlines being the launch customer. Development then moved ahead towards production. Boeing was also working on the smaller 757 jetliner in parallel; turning out two major aircraft in parallel was a strain, reduced by sharing technology between the two aircraft, most notably the advanced cockpit. Interestingly, aircrew have to step up into the cockpit on the 767, while they step down into the cockpit on the 757.

Sub-assemblies were also farmed out to industrial partners -- Fuji, Kawasaki, and Mitsubishi of Japan; Alenia of Italy; Vought and Grumman in the USA; and Bombardier of Canada. Construction of the first '767-200' began in mid-1979, with the prototype performing its initial flight on 26 September 1981. There had been consideration of a '767-100' with lower passenger capacity, but it didn't happen. United Airlines took delivery of its first 767-200 in September 1982. The 767-200 was available with three different maximum take-off weight specifications.

One of the prototypes, incidentally, was modified for use as a US military testbed, the 'Airborne Optical Adjunct (AOA)', later renamed the 'Airborne Surveillance Testbed (AST)'. It had twin ventral fins and a 'hump' running down the top of the forward fuselage to the rear of the wing roots. It was used to test an infrared imaging missile-tracking system, and possibly some other kit. The AST was retired in 2002.

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[2] 767 DETAILS & VARIANTS

* As it emerged, the 767-200 was of what would become a conventional jetliner configuration, with a low-mounted wing, a high-bypass turbofan on a pylon under each wing, and a conventional tail arrangement. All flight surfaces were swept. Construction was primarily of aircraft aluminum, but with extensive carbon-epoxy composite structures as well. The wing had a sweep of 31.5 degrees at quarter-chord, and a dihedral of 6 degrees. As was typical of its Boeing jetliner predecessors, it had an elaborate set of flight control surfaces, the trailing edge of each wing featuring, from tip inward:

• An outboard aileron.
  
• An outboard single slotted flap.
  
• An inboard aileron, which also could function as a flap.
  
• An inboard double slotted flap.

There were four spoilers in front of the outboard flap, and two in front of the inboard flap -- the spoilers being used for roll control, as airbrakes, and for 'lift dumping' on landing to make sure the aircraft settled down on the runway. There was a full-span six-segment slat on the leading edge of the wing. The leading edge of the wing outboard of the engine was electrically de-iced; the inboard leading edge was not de-iced. The tail flight surfaces were of generally conventional arrangement, with rudder and elevators, although the tailplane also had variable incidence. The tail flight surfaces were not de-iced. All flight controls were hydraulically operated.

Two engine options were offered initially, including the General Electric (GE) CF6-80 and Pratt & Whitney (PW) JT9D-7 high-bypass turbofans -- with the more powerful Pratt & Whitney PW4000 added later. There was a range of subvariants of these engines that powered 767 jetliners, with different engine subvariants not only used on different 767 variants, but as options for each 767 variant. The bewildering menu of engine subvariants is best not pursued here in detail; enough to say that the range of thrust was from just under 214 kN (21,800 kgp / 48,000 lbf) to over 267 kN (27,200 kgp / 60,000 lbf), with bigger 767 variants, as might be expected, tending to use more powerful engines.

Of course, the engines had thrust reversers, standard kit for all modern Boeing jetliners. The engine inlets featured de-icing. There was an auxiliary power unit (APU) turbine in the tail section for engine starting and ground power.

There was a fuel tank in each wing and in the wing center section, providing a total fuel capacity of 63,216 liters (16,700 US gallons). The nose gear had twin wheels and retracted forward; the main gear had four wheels each, in a 2x2 bogie arrangement, and retracted from the inner wings towards the fuselage. The wheels had anti-skid brakes.

There were two flight crew, using a 'glass cockpit' with six CRT displays that was advanced for the era. The avionics included radios, navigation aids, and a weather radar, with some variation in particular kit as per customer request. A typical two-class arrangement seated 216, both classes featuring two aisles, with six seats across for 18 first-class passengers and seven seats across for 198 tourist passengers. There were toilets and a galley fore and aft, with toilets in the center section as well. There were fore and aft passenger doors on the left side of the fuselage, with matching service doors on the right side of the fuselage, and an emergency exit over each wing. There was a baggage hold underneath the passenger compartment, with fore and aft baggage doors.

Although no new-production freighter version of the 767-200 was built, from the late 1990s, a number of 767-200 jetliners were converted to '767-200SF (Special Freighter)' configuration, featuring a large loading door on the left forward fuselage and cargo handling facilities.

* The 767-200 was followed by a series of improved variants:

• An extended range '767-200ER' performed its initial flight on 6 March 1984, with initial deliveries from late in that month. The main change was more fuel tankage in the wing center section, raising the fuel capacity by 22%. This variant also had two maximum take-off weight options.
  
• The stretched '767-300' performed its first flight on 30 January 1986, with initial deliveries from September of that year. The fuselage was extended 10.13 meters (33 feet 3 inches) by fore and aft plugs, giving a length of 54.9 meters (180 feet 3 inches). Typical capacity was 269 seats in a two-class configuration. Fuel capacity was the same as for the baseline 767-200. To handle the higher take-off weight, the 767-300 airframe was reinforced and its landing gear strengthened; there were two emergency exits over each wing instead of one, to deal with greater passenger capacity. Apparently there was a option for two additional passenger doors, with the emergency exits then deleted. The 767-300 was one of the first twinjet airliners to go into intercontinental service.
  
• The long-range '767-300ER' variant performed its initial flight on 9 December 1986, with initial deliveries from early 1988. It had more fuel tankage in the wing center section, providing 44% more capacity.
  
• In 1993, Boeing introduced a '767-300F' freighter with an upward-opening cargo door on the left front fuselage, measuring 2.67 meters high and 3.4 meters wide (8 feet 9 inches x 11 feet 2 inches). It had no windows, and could carry up to 24 standard cargo containers. United Parcel Service (UPS) was the launch customer. A number of 767-300 jetliners have also been modified to a similar '767-300BCF (Boeing Converted Freighter)' configuration.
  
• The further stretched '767-400ER' performed its initial flight on 9 October 1999, with deliveries from August 2000. It featured a fuselage stretch of 6.43 meters (21 feet 1 inch), giving a length of 61.4 meters (201 feet 4 inches). Passenger capacity was typically 243 seats in a three-class configuration, 304 seats in a two-class configuration, and 375 seats in a 'cattle car' configuration. The wingspan was increased by 3.66 meters (14 feet 6 inches), giving a span of 51.9 meters (170 feet 4 inches), with the revised wing featuring raked wingtips. Fuel capacity was the same as for the 767-300ER.

A '767-400' had been considered, but it never flew, Boeing finally seeing no market for a short-range / high capacity version. There was talk of an even longer-range '767-400ERX', but it didn't happen. By the end of 2020, Boeing had sold almost 1,200 767s of all variants, and it continues in production, with freighters being notably popular.

With rising fuel prices, winglets became an attractive upgrade option for older 767s without the raked wingtips, with winglet-fitted 767-300ER jetliners re-entering service in 2009 and many airlines obtaining the upgrade. The winglets were estimated to save a significant 6% in fuel burn. Sales of the 767 remain good for the time being, freighters being notably popular, and Boeing also has orders on the books for militarized 767s -- see immediately below.

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[3] MILITARY 767S

* The 767 has had a number of military sales. The Italian Air Force ordered four as mid-air refueling tankers, with deliveries in 2007 and 2008. The Italian tankers were basically 767-200ER machines fitted with a boom refueling system and the stronger flaps of the 767-400, to permit take-offs at a lower rotation angle, as dictated by the boom under the tail. The boom system externally resembled that of the old Boeing KC-135 Stratotanker -- but it was a new design, with greater reliability, lower parts count, and lighter weight than the KC-135 boom unit. The boom unit also included a hose and drogue system, and there were wingtip pods for probe-and-drogue refueling. A total of 100 external lights, some of them infrared, were added to aid in tanker rendezvous operations.

The tankers also featured the more modern cockpit layout of the 767-400, enhanced with military avionics -- particularly military communications and 'identification friend or foe (IFF)' -- and a cockpit workstation for the 'remote aerial refueling operator (RARO)', as opposed to the tail workstation of the KC-135. The RARO workstation included a second seat for training purposes, with the crew members wearing helmet-mounted stereo displays. The pilot and copilot also had a new flat-panel display to allow them to keep an eye on refueling activity. The enhanced military communications suite added VHF & UHF radios, a comsat link, and a Link 16 digital datalink.

The tanker could carry up to 73,000 kilograms (161,000 pounds) of fuel; it could also haul a maximum of 35,000 kilograms (77,000 pounds) of cargo on 19 military-style pallets, or 200 passengers and 9,000 kilograms (20,000 pounds) of cargo. The first machine was integrated by Boeing, but the later machines were integrated by the Finnmeccanica / Alenia Aeronavli facility in Naples, which was already performing 767 freighter conversions. All four aircraft were delivered in 2011.

* In the early 1990s, the Japanese Air Self-Defense Force (JASDF) was interested in acquiring an airborne early warning (AEW) platform, the prime candidate being the Boeing E-3 Sentry, based on the 707 airliner, the standard AEW platform for the US Air Force (USAF) and NATO. However, by that time the 707 was out of production, and so Boeing proposed a 767-based platform fitted with E-3 electronics instead. The JASDF acquired four 'E-767' AEW aircraft, with deliveries in 1998 and 1999. The E-767 has a highly specialized avionics fit, and will be discussed in detail elsewhere.

The JASDF also ordered four 'KC-767J' tankers, with deliveries from 2008 to 2010. That was quite a departure for the Japanese, who have long avoiding obtaining military systems that could imply an offensive posture. The KC-767J was derived from the 767-200ER, and like the Italian machines had a convertible configuration, allowing it to be used as a cargo or troop transport if necessary. The KC-767J only has the boom refueling unit; hose-and-drogue units weren't required. Deliveries were from 2008 through 2010. Italy had actually been the launch customer for the KC-767, but their deliveries had been delayed by problems with the hose-drogue pods, a difficulty that did not affect the JASDF's tankers.

* In 2003, US Air Force announced a deal for a lease of 100 KC-767s from Boeing, with these machines capable of carrying communications or signals intelligence pallets to provide additional capabilities. The lease was to run ten years, and the USAF would then buy the aircraft. Unfortunately, that was at the time of a set of very public corporate meltdowns, most notably of the corrupt Enron firm; Congress was not happy about the deal, with Arizona Senator John McCain leading the charge.

McCain charged that the lease arrangement was a ripoff, and though Air Force officials claimed their accounting showed otherwise, Congress was unimpressed. The Air Force then tried to modify the deal -- but it imploded when it was discovered that Darleen Druyun, a senior Pentagon procurement official involved with the tanker program, had been hired into a senior position at Boeing. That in itself was not illegal, but she had negotiated with Boeing for the job while she was still working at the Pentagon, which was -- and worse, had also passed Boeing details of a proposal by the European Aerospace & Defense Systems (EADS), now Airbus Group, for a competing Airbus-based 'Multi-Role Tanker-Transport (MRTT)'. Druyun was convicted and did prison time, as did Boeing's chief financial officer, Michael Sears. Boeing was fined $625 million USD and the company's chief executive officer, Phil Condit, had to resign.

The Air Force ended up starting over on the tanker deal, initiating a competition for the 'KC-X', as it was designated. In response, Boeing again submitted a design based on the 767, though distinctly different from the KC-767 tankers sold to Italy and Japan. EADS teamed with Northrop Grumman to offer a tanker based on the Airbus A330, essentially a variant of the MRTT that EADS had sold to Australia and several other air arms.

The A330-MRTT proposal would be available earlier; since the Air Force was in a hurry to make up for lost time, that meant a lot. The Airbus also provided better range and more auxiliary cargo carriage. As a result, the Airbus machine, the 'KC-45', was selected in 2008. Boeing promptly challenged the deal, claiming the Air Force had 'moved the goalposts' after issuing the spec, awarding the contract on different criteria than those given at the outset. The Government Accounting Office agreed with Boeing's complaint, and so the award was rendered null and void. The Air Force had to start over again.

That was not only frustrating but also embarrassing, since Northrop Grumman didn't feel they had any chance to win and so dropped out, leaving only Boeing as the 'competitor' for the deal. Fortunately, the Air Force saved some face when EADS decided to compete on their own, again offering the A330-based MRTT. Boeing revised its design after losing in 2008, dropping plans to come up with a new variant airframe and choosing to base the KC-46A 'NewGen' tanker on a 767-200. The KC-46A was selected as the winner, the primary factor being lower price.

* The KC-46A looks much like the KC-767 machines, but under the skin it is somewhat different, being based on an unproduced 'long-range freighter' version of the 767-200; the basic airframes of the KC-767s are also much the same as their airliner siblings, while the KC-46A has some airframe modifications. It is powered by two Pratt & Whitney PW4062 turbofan engines providing 267 kN (27,200 kgp / 60,000 lbf) thrust each, and has advanced avionics -- leveraged off the Boeing 787 Dreamliner discussed below, with the KC-46A featuring much the same cockpit layout. The KC-46A has a drogue refueling pod under the centerline and each wing, for a total of three, and a boom refueling unit derived from that of the McDonnell Douglas KC-10. The KC-46A also features a refueling socket of its own, on the top of the aircraft just behind the cockpit.

The KC-46A is a 'multi-mission' aircraft, capable of transport operations. There's a large cargo loading door on the left front fuselage -- photos suggest the Japanese and Italian KC-767s don't have the cargo door -- plus an internal cargo handling system, with total cargo load of up 29,485 kilograms (65,000). Removeable seats can be fitted in place of cargo, with typical seating for 58 passengers and up to 114 in a pinch; the aircraft can also be fitted for medical evacuation, with a total load of 58 litters and seated passengers.

Four prototypes of the 'Pegasus', as it was officially named, were built. The first performed its initial flight on 28 December 2014; it lacked tanker kit, this '767-2C' machine being used for airframe systems tests and qualifications. The second was in full tanker configuration, while the third was also in 767-2C configuration, with both of these machines flying in 2015. The fourth, which took to the air in the spring of 2016, was in full tanker configuration.

The initial contract was for 18 KC-46As to be delivered by 2017, with the ultimate buy expected to run to 179 aircraft, the last to be delivered in 2027; however, there have been delays, with the Air Force considering penalties. Although the KC-46A fared poorly against the Airbus MRTT in international competition, the JASDF ordered four from late 2015, to complement their existing KC-767J fleet, while Israel ordered eight in 2020.

* It should be added that one stock 767-200ER was also converted to a 'Multi-Mission Tanker Transport (MMTT)' for the Colombian Air Force by Israel Aerospace Industries (IAI), this machine featuring a drogue refueling pod under each wing, plus cargo-handling facilities or troop seating. In 2013, the Brazilian Air Force ordered three similar conversions from IAI of 767-300ER machines. IAI has test-flown a 767-300ER with a boom refueling unit, and is offering 'smart tanker' options to customers, adding modules for signals intelligence, communications relay, or 'flying command post' operations.

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[4] BOEING 777

* In the mid-1980s, Boeing began investigating a new jetliner in the size range between the 767 and 747, with 300 seats; one of the motivations was to provide a replacement for retiring Douglas DC-10 jumbo jets. Initially the new aircraft was seen as a stretched 767 and was accordingly designated the '767-X' -- but as the investigation progressed, the 767 design ended up being tweaked further and further. Simply stretching the 767 to gain the desired number of seats made it too long for typical airport ramp; when the program was finally given the green light for full development in October 1990, it envisioned a new aircraft only generally modeled on the 767, designated the '777'.

Even then, much remained uncertain about the aircraft's design, with specifics ironed out through discussions with customers. Customers, it turned out, wanted a fuselage wider than offered by competing aircraft such as the McDonnell-Douglas MD-11 and the Airbus A340. The wide cabin was taken as a base reference, the 777 then being effectively designed from the 'inside out'. Although Boeing jetliners had traditionally used a 'double bubble' cross section, with a large 'bubble' topside and a smaller bubble below, a purely circular cross section seemed preferable.

That resolved, there was the question of the number of engines: two, three, or four. Four seemed the most practical given the size of the 777, but that would have increased expense; a tri-jet configuration could do the job, but fitting an engine in the tail would be structurally troublesome. Two engines would be optimal if sufficiently powerful new turbofans became available in a timely fashion. On talking to engine manufacturers about the prospect of such engines, all replied that it was basically not a problem. Two engines it was.

A new, big, aerodynamically efficient wing was required; the span was so wide as to lead to the inclusion of folding wingtips, for customers who thought the span was a difficulty for ground handling -- though as it turned out, nobody would. It might have been interesting to have one take off with its wingtips up; unless highly effective precautions were built into the aircraft, Murphy's law suggests it would have inevitably happened.

Two classes of 777s were envisioned, a transcontinental 'A Market' class with a capacity of 375 passengers and an intercontinental 'B Market' class with less passenger capacity and more fuel. Subvariants would be offered in each class for more range or capacity. Customer reaction was enthusiastic, and so the first prototype of the 777, a '777-200' variant, took to the air on 12 June 1994. Eight other aircraft joined the test program, with certification and customer deliveries in 1995.

* The 777-200 provides a baseline for the 777 family. It looked very much like the 767 to the point where the two could be somewhat difficult to tell apart, but it was substantially scaled up, with an empty weight about 80% greater; it was a monster of a twin-engine aircraft, with its handling on approach definitely suggesting a big machine. It was made mostly of aircraft aluminum, though 10% of the weight of the airframe was composite material.

There were, as with the 767, multiple options for engines, including PW4000, GE90, and Rolls-Royce RR800 turbofans. Depending on model, engine thrust ranged from 338 kN (34,500 kgp / 76,000 lbf) to a staggering 514 kN (52,400 kgp / 115,540 lbf) thrust. Of course, the heavier variants tended to have the more powerful engines. Along with sheer power, these engines also provided excellent fuel economy, low emissions, and low noise. Fuel stowage was in the inner wings and wing center section, with total capacity of 117,348 liters (31,000 US gallons). There was an APU in the tail.

The general flight surface arrangement generally followed that of the 767, with double slotted flaps inboard on each wing, followed by an inboard aileron that also acted as a flap, then a single slotted flap, and finally an aileron. There was a full-span leading-edge slat, in seven segments, and spoilers -- two just forward of the inboard flap, five ahead of the outboard flap. Tail flight surface arrangement was conventional, with a trimming adjustable tailplane. Landing gear arrangement was like that of the 767, with two-wheel nose gear, retracting forward, and main gear retracting in from the wings towards the fuselage -- though in the case of the 777, each main gear had six wheels, in three rows of two.

The 777 was the first Boeing jetliner with a 'fly-by-wire' flight control system, with a flight processor system, the 'Aircraft Information Management System (AIMS)' at the core. Incidentally, the 777 was also the first such to be developed completely using a 'computer-aided design' system. The 777 featured a 'glass cockpit' with six flat-panel color displays, and had other features such as a GPS-INS with laser gyros.

There were two flight crew, with typical passenger capacity of 305 in a three-class arrangement; 375 or 400 in a two-class arrangement; and up to 440 in a ten-across one-class 'cattle car' arrangement. There were four passenger doors on each side of the aircraft. Positioning of galleys and toilets fore, aft, and midsection was flexible, easily rearranged as per client request. There was a cargo hold under the floor of the passenger compartment. An optional crew rest module could be installed in the cargo hold, complementing a default crew rest module with two bunks on the flight deck.

* The initial 777-200 was followed by improved variants:

• The extended-range '777-200ER' was introduced in 1996. It was externally indistinguishable from the 777-200, but had 46% more fuel capacity, providing a maximum range of 14,300 kilometers (8,890 miles / 7,700 NMI), and of course had a higher gross take-off weight.
  
• The stretched '777-300' model was introduced in 1997, this variant featuring a 10.1 meter (33 feet 4 inches) fuselage stretch for a total length of 73.9 meters (242 feet 4 inches); fuel capacity was the same as for the 777-200ER. It had a tail bumper, plus a videocam system to help the aircrew in ground handling.
  
• The 777-300 was followed in turn by an extended-range '777-300ER' model, with 6% more fuel capacity than the baseline 777-300 and raked wingtips. Initial delivery, to Air France, was in 2004. It would prove very popular.
  
• An ultra-long-range '777-200LR' was introduced in 2005, with 74% more fuel capacity relative to the baseline 777-200 and raked wingtips. One set a distance record for a nonstop flight of a passenger aircraft from Hong Kong to London.
  
• The latest version is the '777F' air freighter, based on the 777-200LR, with the 777F rolled out in 2008. It has a large cargo door on the rear fuselage on the left, and no passenger windows; maximum payload capacity is 103,000 kilograms (226,000 pounds). Air France Cargo was the first customer, having been a big operator of 747 Freighters, no doubt to the irritation of Airbus officials in Toulouse. Boeing has also been considering freighter conversions of older 777-200-series jetliners.

Boeing has worked hard to keep the 777 line up-to-date, adding small refinements to production and for upgrades. One was elimination of the tail bumper, as a minor aerodynamic improvement and for weight reduction; the aircraft's flight control system was revised to automatically spot a potential tailstrike, and compensate for it. There have been smaller aerodynamic refinements as well. Other changes have included lighter insulation blankets, lighter hydraulic fluid, and smaller weight-reduction measures; interior changes; and engine component updates.

Over 1,600 777 jetliners had been built by the summer of 2020. Although the Boeing 787 is seen as the heart of the company's future, for the present the 777 is a good money-maker, and there are no plans to abandon it. Boeing is considering a next-generation '777X' family for service entry no earlier than 2019, featuring advanced GE9X turbofan engines and new all-composite wings, as well as weight reductions plus updated avionics and interior. Two versions are planned, the '777-8X' and '777-9X'.

The 777-9X was the first to fly. It's a stretched machine, with a range of 13,920 kilometers (8,655 miles / 7,525 NMI) in a 406-seat two-class layout; or 14,910 kilometers (9,270 miles / 8,060 NMI) in a 349-seat three-class layout. With an optional rear cargo door, it will be able to haul 48 LD3 cargo containers in the lower hold, up from the 44 of the 777-300R. It has a length of 76.5 meters (251 feet), making it the longest airliner built to date. Its empty weight is only slightly less than that of a classic 747-400.

The initial prototype was rolled out in 2019, with initial flight of it and a second proto in early 2020. There was a holdup due to GE9X problems. Initial delivery is supposed to be early 2021, though the COVID-19 pandemic has thrown a lot of confusion into the airline industry.

The 777-8X is to replace the 777-300R, featuring a long range of 16,075 kilometers (9,995 miles / 8,690 NMI) in a 365-seat two-class layout; or longer range of 17,160 kilometers (10,665 miles / 9,275 NMI) in a 303-seat three-class layout. The 777-8X is slated to enter service in 2022 -- but again, the pandemic has thrown plans into flux, making it hard to talk about futures for the time being.

The 777X machines have an extended wingspan of 71.75 meters (235 feet 5 inches), with the wingtips folding up to ensure that the jetliner can fit into existing aircraft gates. The cockpit has five large color touchscreen displays, up from the six smaller displays of its predecessors.

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[5] BOEING 787

* From the beginnings of Airbus in the 1970s, the competition between Airbus and Boeing was intense and bitter, with each company denouncing and attempting to steal a jump on the other. In 2000, Airbus committed to development of the 'A380' super-jumbo jet, a giant aircraft that caught the imagination of the airlines. Boeing's reaction was clumsy, the company proposing major updates to the classic 747 jumbo jet and a new high-speed 'Sonic Cruiser' -- both of which the airlines greeted with indifference.

Boeing officials ultimately decided not to match the A380. The A380 was predicated on a 'hub & spoke' model of air travel, with a super jumbo jet only really practical to haul a mass of passengers between major hubs; passengers would have to transfer to other transport to get to 'spoke' destinations. Boeing believed that what passengers wanted were more direct-to-destination flights, implying a smaller aircraft. In addition, fuel costs were on an upward curve, and so Boeing needed to make sure the new aircraft was as fuel-efficient as possible.

In early 2003, Boeing committed to the '7E7', which became the '787 Dreamliner' in 2005. The 787 was configurationally a twinjet along the lines, and roughly the size, of the 767, but it was a new-design aircraft, most significantly featuring widespread use of lightweight carbon-epoxy composite materials, the 787 to be one of the first large civil aircraft to be largely built of composites. A number of subcontractors were signed up for the project, with a consortium of three Japanese firms -- including Mitsubishi, Kawasaki, and Fuji -- coming on board as full risk-sharing partners, contributing about a third of the development cost. The Japanese had experience in construction of composite assemblies seen as critical to the 787 project.

Extensive use of composite materials allowed Boeing to consider new airframe construction concepts, abandoning the traditional aircraft framework and using large integral composite assemblies for strength. The idea was to obtain the maximum reduction in airframe weight to improve fuel economy -- though by taking such a new approach, problems with the composite assemblies would lead to program delays, and the weight savings wouldn't turn out to be quite as much as expected. However, along with being lighter, composites were also less prone to corrosion than traditional aircraft aluminum, and they were also easier to form into more aerodynamically-refined shapes.

Three variants of the 787 were planned initially, including the baseline '787-8'; a stretched '787-9'; and a medium-haul '787-3', the last being canceled unbuilt. The first prototype of the Dreamliner, a 787-8, performed its initial flight 15 December 2009 -- about two years behind original schedule, development not having been entirely smooth. Six aircraft were flown in the test program, with initial delivery of a production machine, to the launch customer All-Nippon Airways, on 25 September 2011. The first prototype of the 787-9 performed its initial flight on 17 September 2013.

* As noted, the 787 has an overall configuration not all that different from its Boeing ancestors like the 767 and 777, being a low-wing aircraft with twin pylon-mounted turbofans, and all-swept flight surfaces; it is similar in size to the 767. It is, however, a completely new design. Along with an airframe half composites by weight, it has optimized aerodynamics; modern avionics; all electric systems; plus fuel-efficient, clean-burning, and quiet fanjets. Boeing claims the 787 is easier, safer, and cheaper to operate, with 20% less fuel consumption than its predecessors.

Very significantly, while traditionally jetliners have used 'bleed air' from the engines to drive most aircraft systems, the 787 is based on electric systems to perform cabin pressurization, de-icing, and other functions. The engines still have to provide the motive power for these systems by driving electric generators, but the overall result is more efficient, and replacing the cumbersome plumbing of bleed air ductwork with electrical wiring means less weight.

The wings feature raked wingtips. Control surface arrangement is more or less along the lines of the 787's predecessors, with full-span leading-edge slats in seven segments, inboard flaps, inboard aileron, outboard flaps, outboard aileron, and spoilers leading the flaps. All flaps are single slotted; there are three spoilers ahead of the inboard flap, four ahead of the outboard flap. Sources also mention a puzzling 'sealing' leading-edge Krueger flap at each engine pylon, but details are unclear. The wings feature electrical de-icing. The tail surfaces are conventional, with rudder and elevators, the tailplane being adjustable for flight trim.

Customers can choose between two types of engines, the Rolls-Royce Trent 1000 or new GE GEnx fanjets. Both are state of the art, providing high thrust-to-weight performance, improved fuel efficiency, low noise, and low emissions. Thrust levels are on the order of 311 kN (31,750 kgp / 70,000 lbf). One of the first things anybody notices about the 787 is that its engine nacelles have a zigzag edge around the rear. This reduces exhaust noise, which not only translates into less need for aircraft sound insulation for passenger comfort, but fewer complaints from people living near airports.

Boeing claims the noise footprint of the 787 is only 60% that of its predecessors, allowing the aircraft to operate from airports where noise restrictions would otherwise have banned it. Incidentally, the 777X will not have the zigzag edge; either the GE9X engines of the 777X will be so quiet as to need no further silencing, or some other approach has been found to do the job.

There is an APU for engine starting and ground power. There are fuel tanks in the inner wings and wing center section. There are two wheels on the nose gear and it retracts forward; there are four wheels on each main gear, in a 2x2 arrangement, with the main gear retracting inward, pivoting from the wings to the fuselage.

* The 787's interior design is particularly innovative. Passengers coming into the front of the aircraft enter through an open 'lobby' instead of passing by a galley, greeted by a blue LED lighting arrangement that suggests a skylight. The lighting is provided by LEDs throughout the passenger cabin; not only are the LEDs more reliable and less power-hungry, they also are more controllable, with lighting sequences designed to reduce flight weariness and, hopefully, jet lag.

Lighting remains standard during boarding and cruise flight, being adjusted to warmer tones during meals. After eating, the cabin is bathed in a relaxed lavender hue, with the lighting fading down when it's time to sleep. The most impressive part is the wake-up, with the light rising in a sunrise sequence from purples and oranges to yellows and then white light against a blue sky. Boeing is gradually adopting much the same interior scheme for other current-production jetliners.

As far as the annoyance of being hit in the eyes by the sun when somebody opens a window shade goes, the 787 doesn't have window shades: the windows have an electrochromic dimmer system. A passenger can change the transparency of a window with a switch, with the flight crew able to regulate the level of transparency of all the windows. Thanks to the composite construction, the windows are also 65% larger than on previous Boeing jetliners, with a tall aspect ratio so both kids and basketball players can see out.

While coach passengers can't expect to get much more of a footprint to themselves than before, the ceiling is arched to give more sense of spaciousness. The overhead storage bins are about 20% bigger, but they drop down when opened and pop back up when closed to give more headspace. In addition, again thanks to the 787's composite construction, humidity can be increased without worries about promoting corrosion, and cabin pressure can be increased as well -- to an altitude equivalent of about 1,830 meters (6,000 feet) instead of the traditional 2,440 meters (8,000 feet).

The 787 is designed for very quiet operation, both to improve passenger comfort and to meet public noise regulations, with features such as the serrated rear edge of the engine nacelles previously noted. Even the fan blades are designed to be quieter. Another feature is a 'Smoother Ride Control' capability in the aircraft's flight control system to reduce bumpiness from turbulence.

The flight deck features a glass cockpit compatible with that of the latest 777s. The flight crew has rest bunks fore and aft. There are twin aisles in all passenger sections, with 4-across seating in first-class, 6 in business class, and from 7 to 9 in economy class. Typical seating is 242 passengers in 3-class seating; 310 passengers in two-class seating; or 375 passengers in 1-class seating. There are four doors on each side. There is a cargo hold under the floor, all access doors on the right of the aircraft, with baggage doors fore and aft of the wing and a large cargo door in the rear. Cargo volume is 125 cubic meters (4,400 cubic feet).

Final assembly of the 787 is at the Boeing plant in Everett, Washington. Large assemblies are hauled to Everett by four '747 Dreamlifter' cargo haulers, modified from 747-400 jetliners by fit of an oversized fuselage.

* The 787-9 is 6.1 meters (20 feet) longer than the 787-8, for a total length of 62.8 meters (206 feet); empty weight is about 6% greater. Passenger capacity is typically 280 seats in a three-class configuration, or 360 passengers in a two-class configuration. Boeing has not publicized a one-class configuration -- but given that the 787-9 has about 16% more capacity than the 787-8, that would give approximately 435 passengers for 'cattle car' operations. The 787-9 was originally supposed to have a wider wingspan than the 787-8, but the longer span led to excessive complications, and so Boeing turned to a scheme called 'hybrid laminar flow control (HLFC)' to improve the efficiency of the shorter wing. Range is about 5% more than the 787-8. Deliveries began in 2014, the first customer being Air New Zealand.

Is Boeing 777 Or 787 Bigger

In mid-2013, the company announced a '787-10' variant, stretched by 5.49 meters (18 feet) relative to the 787-9 to give a length of 68.3 meters (224 feet). Other than the stretch and modified landing gear to avoid tailstrikes, the 787-10 is much the same as the 787-9. Passenger capacity will be 320 seats in a three-class configuration; range is only about 13,000 kilometers (8,450 miles / 7,000 NMI), the target market being high-density trunk routes and not very long range connections. Initial deliveries were in 2018, the first customer being Singapore Airlines.

Boeing offers VIP configurations of the 787; an air freighter variant has been considered, but there's been no commitment to it. There has been very little discussion of military variants yet, though of course VIP variants are likely to be acquired as presidential aircraft. Boeing sees the market for aircraft in the class of the 787 as running to 3,500 aircraft over the next 20 years, and hopes to capture half that market.

Unfortunately, the service introduction of the 787 was marked by a number of technical problems and groundings, the worst being due to a set of battery-pack fires that attracted wide public attention. The big bugs are gone now, and the 787 is selling -- or selling as well as might be expected, given the pandemic recession. Almost a thousand had been sold by the end of 2020.

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[6] COMMENTS, SOURCES, & REVISION HISTORY

* The 787 may represents the end of a line of Boeing jetliner evolution tracing back to the Boeing 707. The reason is fuel costs; fuel prices have been on a generally steady upward curve since the beginning of the 21st century, and simple economics demands that the next generation of airliners be far more fuel-efficient than the 787, even at some penalty in performance, or few customers will be able to afford to fly. Boeing has conducted research, partly in collaboration with the US National Aeronautics & Space Administration, on next-generation airliners. The more conservative concepts do follow current jetliner design schemes, but with greatly extended wings, with folding for ground handling.

A more radical design approach has focused on a 'truss-braced wing (TBW)' configuration, with greatly extended (folding) wings reinforced by a attaching a strut or truss. A Boeing design for such a TBW aircraft, made of composite materials, would have fuel savings of 40% using leading-edge high-bypass turbofan technology -- and over 60% with 'hybrid' propulsion, for example electrically-driven propfans powered by fuel cells. The aircraft would only be about 10% slower than existing jetliners, an acceptable performance penalty. Incidentally, the Boeing TBW design is extremely graceful, along the lines of the more elegant airliners of the late 1930s, updated for the 21st century. Even more radical airliner configurations have been considered; what happens in the next generation remains to be seen.

* One fact about the 767 that needs to be mentioned in this survey is the sad role two 767s played in the terrorist attacks the World Trade Center towers in New York City on 11 September 2001. A hijacked 767-200ER, American Airlines Flight 11, was first deliberately crashed into the north tower, followed by the deliberate crash of a 767-200, United Airlines Flight 175, into the south tower about 15 minutes later, the resulting infernos causing the towers to collapse. Over 3,000 people were killed, including all on board the two jetliners.

On a more upbeat note, on 23 July 1983 a 767-200, Air Canada Flight 143, was en route from Montreal to Edmonton via Ottawa when it ran out of fuel due to a servicing error. The pilot managed to 'dead stick' the powerless jetliner to touch down on an old airstrip at Gimli, Manitoba. Nobody was seriously hurt, and the 'Gimli Glider', as it became known, returned to service, being finally retired in 2008.

Incidentally, the KC-46 designation for the USAF's 767 tanker more or less recycles the designation of the World War II Curtiss C-46 Commando transport. It is amusing to think that the KC-46A will acquire the original's nickname: 'Dumbo', for the Disney flying elephant.

* As concerns copyrights and permissions for this document, all illustrations and images credited to me are public domain. I reserve all rights to my writings. However, if anyone does want to make use of my writings, just contact me, and we can chat about it. I'm lenient in giving permissions, usually on the basis of being properly credited.

* Sources include:

• 'A3XX Initiates New Round Of Airbus, Boeing Rivalry' by Pierre Sparaco (and following), AVIATION WEEK, 24 July 2000, 116:126.
  
• 'Basic Configuration Set For Longer-Range 777s' by Bruce A. Smith, AVIATION WEEK, 29 January 2001, 46:47.
  
• 'Longer Range 767-400ER Design Set To Accommodate 747X Engines' by Bruce A. Smith, AVIATION WEEK, 5 March 2001, 49:50.
  
• 'First Off The Line [Italian KC-767 tankers]' by David A. Fulghum, AVIATION WEEK, 7 February 2005, 50:52.
  
• 'On Its Way [777 freighter for Air France]' by Michael Mecham, AVIATION WEEK, 30 May 2005, 40:41.

A number of volumes of JANE'S ALL THE WORLD'S AIRCRAFT were consulted as well.

* Illustrations credits:

• 767-200 / Denver International Airport / 2005 / author
  
• 767-200 / Seattle-Tacoma International Airport, Washington / 2005 / author
  
• 767-300 / 2008 / Eddie Maloney / Creative Commons Share Alike License
  
• JASDF KC-767J / 2015 / ~ChiyodaI / Creative Commons Share Alike License
  
• KC-46A with F-35 / Boeing
  
• 777-200ER / Seattle-Tacoma International Airport, Washington / 2005 / author
  
• 777-9X / Boeing
  
• 787-8 / Munich Airport / Curmedia / Creative Commons Share Alike License
  
• Boeing Sky interior / Boeing
  
• 787-9 / 2014 / ~pjs2005 / Creative Commons Share Alike License
  
• Boeing truss-braced wing jetliner concept / Boeing

Compare Boeing 777 And 787

* Revision history:

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Boeing 777 And 787 Common Type Rating

Two of Boeing’s most iconic series of commercial jets include the 777 and 787. When most people hear the word “777” or “787,” they immediately envision the American aerospace manufacturing company. Boeing has become known throughout the world for its 777 and 787 series. Jets in these two series are used by dozens of commercial airlines. So, what’s the difference between the 777 series and the 787 series?

Variants

For starters, the 777 series includes more variants than the 787 series. In the 777 series, Boeing offers the 777-200, 777-200ER, 777-200LR, 777-300 and the 777-300ER. In the 787 series, Boeing offers the 787-9, 787-10 and the 777-200. Specifications vary depending on the variant. Nonetheless, there are more variants available in the 777 series than the 787 series.

Size

Another difference between the 777 and 787 series is their size. Most of the 777 variants are longer than the 787 variants. The biggest 777 variant measures over 242 long, whereas the biggest 787 variant measures just 186 feet long. Both the 777 and 787 series consist of relatively long narrow-body airplanes, but those in the former series are typically longer than those in the latter series.

Age

Boeing 777 300 Seat Plan

As you may have guessed, the 777 series is older than the 787 series. Boeing began producing 777 airplanes in 1993. In 1994, United Airlines became the first commercial airline to use the 777 in its fleet. Boeing, however, didn’t begin producing 787 airplanes until 2007, with the first official flight occurring in 2009. The 787, of course, is the successor to the 777. It’s Boeing’s latest series of airplanes. Boeing still produces 777 airplanes, but it has since shifted much of its resources towards the production of 787 airplanes.

Efficiency

In terms of efficiency, the 787 series is superior to its 777 counterpart. 787 airplanes consume less fuel than 777 airplanes, making them an attractive choice among commercial airlines. Jet fuel isn’t cheap. Depending on the quality, as well as other factors, a single gallon can cost over $5. And considering that many airplanes hold over 40,000 gallons of fuel, filling up the tank can be quite expensive. Fortunately, commercial airlines can save money on fuel costs by investing in 787 airplanes. It uses a more efficient fuselage and engine configuration, allowing for cost-savings benefits in the form of lower fuel consumption.

Boeing 777 Seating Chart

Passengers

Boeing 777 787 Pantip

Because they are larger, 777 airplanes typically support more passengers than 787 airplanes. Both types of airplanes can hold hundreds of passengers. With that said, the 777 series is able to hold a few dozen more passengers than the 787 series. Of course, passenger accommodation varies depending on the specific variant. Some variants support more passengers than others. Regardless, most 777 variants are able to hold more passengers than 787 variants.