The new Boeing 777X jetliner had a successful 3-hour, 51-minute flight over Washington state before landing at Seattle's Boeing Field. Based on the 777 and with proven technologies from the 787 Dreamliner, the 777X will deliver 10% lower fuel use and emissions and 10% lower operating costs than the competition through advanced aerodynamics and the latest-generation carbon-fiber-composite wing.

The test fleet, which began ground testing in Everett, Wash., last year, will endure a comprehensive series of tests and conditions on the ground and in the air over the coming months to demonstrate the safety and reliability of the design. Boeing expects to deliver the first 777X in 2021.

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