Boeing’s new jet set to take flight into troubled skies for jumbos

Boeing Co.’s newest plane is preparing to spread its gargantuan wings—so long the tips are hinged—and rumble into the skies over the Washington factory complex constructed a half century ago for the original jumbo jet.

First flights typically mark a crowning technological achievement for planemakers, capping years of invention and problem-solving. This flight, however, will be clouded with uncertainty for Boeing.

The 777-9 is the planemaker’s first new model since two fatal crashes led to the global grounding of its 737 Max. As the company works to restore its reputation for safety and technical prowess, the new aircraft will face heightened scrutiny from regulators, airlines and investors.