The 777X is a larger and more fuel-efficient model of the Boeing Co.ís popular 777 wide-body, which is built in Everett, and Emirates is the worldís largest operator of those planes.
The companies first announced a commitment to do the deal at the Dubai Airshow in November. Included in the order are 115 777-9Xs and 35 777-8Xs. The list price for the 400-passenger 777-9X is $377.2 million, while the list price for the 777-8X ó which can carry up to 350 passengers ó is $349.8 million.
Emirates Airline also has purchase rights for an additional 50 aircraft. If exercised, it could raise the value of the deal to about $75 billion ó again, at list prices.
Production of the 777X is expected to start in 2017, with first delivery targeted for 2020.
Last month Boeing, based in Chicago, signed a deal for five Japanese companies to make key components for twin aisle 777X jets but the contract doesnít include the wings, which were a source of delays for the 787 Dreamliner. The Japanese manufacturers will make about 21 percent of the new planeís structural components, including fuselage sections and landing gear wells.