In a commercial airplane first, the 777x's will have foldable wingtips. On Wednesday, the company showed just how they'll work.
Boeing's new 777x wasn't at the Paris Air Show this week, but the company still did its best to show off the airliner to the world. On Wednesday, it tweeted a video highlighting the plane's most prominent feature, wingtips that fold upward.
The moving wingtips -- the first of their kind on a commercial jetliner --- will cut the 777x's enormous wingspan from 235 feet down to just under 213 feet. That will let the plane fit at airport gates where existing 777s currently operate, while still giving the wing its full lift capability in flight. The Airbus A380's longer 261-foot wingspan forced airports to make expensive modifications to airport terminals when it debuted in 2007, something Boeing is trying to avoid.
As the wingtips are a new technology, Boeing had to seek approval for their design from the Federal Aviation Administration. "Boeing has determined that a catastrophic event could occur if the airplane wingtips are not properly positioned and secured for takeoff and during flight," reported an FAA document published in May 2018. "The applicant must show that such an event is extremely improbable, must not result from a single failure, and that appropriate alerting must be provided for the crew to manage unsafe system-operating conditions."
In that document, the FAA set 10 conditions that the wingtips must meet before it will certify the aircraft. Those include having more than one method to alert the flight crew that the wingtips are not properly positioned prior to takeoff, a mechanism to prevent takeoff if the wingtips aren't extended and another mechanism to prevent the wingtips from folding during flight.
The 777x is the latest member of 777 family, which first took to the air 25 years ago this month. Built and designed to compete with the Airbus A350, the 777x will consist of two models. The 777-8 will fit about 384 passengers and have a range of 8,690 nautical miles (about 10,000 miles) and the 777-9 will fit 426 passengers and a range of 7,285 nautical miles (at 251 feet, the 777-9 also will be the longest commercial plane). Both models will be made from composite materials and have larger windows and a redesigned passenger cabin.
Boeing rolled the first 777x out of its factory in Everett, Washington, in March. Though aircraft companies normally hype rollouts as media events, Boeing opted for a lower-key, employee-only debut following the two crashes of its 737 Max, which killed 346 people.
