Emirates has signed on the dotted line for 150 of Boeing's new 777X jet, finalising an order worth a staggering US$56 billion at list prices.
The Gulf carrier's Boeing 777X fleet will be split into 115 of the 777-9X variant, which will carry up to 407 passengers, and 35 of the more compact 777-8X, with first flights from 2020.
Emirates also holds purchase rights on an additional 50 Boeing 777X jets, on top of this order first announced as a "commitment" at the 2013 Dubai Airshow.
Emirates is the world's largest airline flying the Boeing 777 series, which currently tops out at the long-range 777-300ER.
"We fly 138 of these efficient planes across the globe spanning the USA and Latin America in the west, to New Zealand and Japan in the East" said Emirates president Sir Tim Clark.
"The 777X will offer us operational flexibility in terms of range, more passenger capacity and fuel efficiency."
Boeing claims the 777-9X "will be 12 percent more fuel efficient than any competing airplane, necessary in today's competitive environment."
Other airlines buying the Boeing 777X including Lufthansa, Cathay Pacific, Etihad Airways and Qatar Airways.
Long wings for the win
The Boeing 777X will adopt some 787 technology such as extra-long wings made from carbon-fibre composites rather than metal.
However, the tips of those wings will fold up when the 777X is on the ground, dropping down and locking into place before the plane takes off.
It's a high-tech trick required to help the 777X fit into airport boarding gates and taxiways designed for the smaller members of the 777 family – the 777X's wingspan is expected to exceed that of today's largest 777-300ER by 6 metres (20 feet), making them even longer than Boeing's 747-8 jumbo jet.
In fact, it's not even 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.
The reason for Boeing's love affair with long wings? They'll let the 777X fly further, increase fuel efficiency and carry more passengers and cargo.
"The range and aerodynamic quality of this aircraft is all about the wing," relates Emirates chief Tim Clark, who has used his airline's muscle to create a jet he was happy with.
The stretched wingspan means the Boeing 777X "flies faster, it carries more, it is far more fuel efficient."
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