The first Boeing 777X will trundle off the production line in 2018, a Boeing exec has revealed, as the company edges closer to commercial flights of the new long-range jets from 2020.
That debutante is likely to be the Boeing 777-9X, although the X will be dropped as the plane makes its journey from blueprint to blue skies, to become the 777-9.
It will be followed by the smaller but longer-range Boeing 777-8X, or 777-8 (note the nod to the naming conventions adopted for the Boeing 787 Dreamliner).
Bob Feldmann, Boeing's vice president for the 777X project, told The Seattle Times that the first 777X will roll off an early production line – one currently used to ramp up Boeing 787 production – in 2018.
Boeing is on track on finalise the 777X's design configuration later this year. "It’s an exciting time as we begin to define the world’s next great airplane" Feldman says.
The manufacturer has already notched up orders for 286 of the 777X jets, with the lion's share going to 777 stalwart Emirates in 35 of the 777-8s and 115 of the 777-9s.
Gulf neighbour and rival Etihad has inked a deal for 8 777-8s and 17 777-9s.
Qatar Airways, Cathay Pacific, Lufthansa and ANA have all opted for the larger 777-9 alone with orders.
The X factor
The latest addition to Boeing's best-selling 777 family, the 777X is being spruiked as "the largest and most efficient twin-engine commercial jet in the world, with the lowest operating cost per seat of any commercial airplane."
The 777-9X is spec'd for 400 passengers in a three-class cabin layout with a peak range nudging past 15,185km (8,200 nautical miles).
The 777-8X will trim the seat count to 350 passengers but with a maximum range over 17,220km (9,300 nautical miles).
In both cases, improved design and new-generation engines will see the planes burn less fuel than today's 777s.
Long wings for the win
Part of that advanced design: sweeping wings made from carbon-fibre composites rather than metal, which span 235 feet (71.6 meters) to boost aerodynamic efficiency.
However, the tips of those wings will fold up when the 777X is on the ground to reduce the wingspan by some 7 metres (23 feet).
These 'swingtips', as Boeing calls them, are required to make the 777X fit into airport boarding gates and taxiways designed for the other members of the 777 family rather than demand expensive airport modifications.
(It's not exactly a new idea: Boeing patented it in 1995 for the original Boeing 777, and while no airline ever ticked this option box on their order, a full-scale model of the folding wingtip is on display at Boeing's Museum of Flight in Seattle.)
Inside the Boeing 777X
Boeing will also adapt key aspects of its 787 Dreamliner series to shape the passenger experience of the 777X.
The 777X will include a lower effective cabin altitude of 6,000 feet; oversized windows set higher into the cabin; and what Boeing promises will be "economy class seat widths up to 18 inches wide," although the choice of configurations and seat widths will in the end fall to airlines buying the big bird.
The rest of the creature comforts which Boeing has in mind for the 777X – which is slated to begin production in 2017, with first commercial flights from 2020 – are a mash-up of the Boeing 777 family interior with the 787's cabin innovations.
For starters the cabin altitude will be pegged at 6,000 feet and humidity levels boosted, with both traits being "comparable to the 787 Dreamliner" in order to reduce the effects of inflight fatigue and jetlag.
Also like the Dreamliner, the enlarged windows of the 777X will be positioned higher on the fuselage so they're at eye level for a larger percentage of passengers, to allow more light into the cabin and a sense that there's an 'outside' out there from even the dreaded middle seats.
There should be lower cabin noise thanks to new engine nacelle design, better cabin insulation and even the installation of twice as many air nozzles which will funnel triple-filtered air at reduced velocity for less noise.
Boeing also says the 777X will introduce an "all-new interior design that allows airlines to customise their cabin architectures by class."
"This innovation includes an adaptable suite of parts that facilitates choices in overhead ceiling and stow bin configurations, allowing airlines to create the feeling of separate and distinct cabins that meet both airline and passenger needs."
Boeing suggests this as a possible high-tech 777X cabin, perhaps assuming that Tron Airlines is the launch customer...
Of course, no modern jet can get by without LED mood lighting, so that's a given right out of the box.
"The 777X will redefine the total passenger experience" promises Dennis Eng, Boeing's Director for 777X Interiors.
"All of the interior features we are exploring and designing into the new airplane are working together as a package to create an exciting new passenger experience."
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