Boeing has confirmed the 777X family will be introduced with folding wingtips as a baseline feature.
Inserting the folding mechanism will allow the 777-9X and 777-8X to use a wingspan almost 5m longer than the 777-300ER, but still fit into the same airport gates and taxiways.
Scott Fancher, Boeing vice-president of airplane programmes said during a briefing at the Paris air show today, that the folding wingtips drew many questions from potential customers, but the curiosity faded as the design satisfied any concerns.
The folding mechanism will be no more complex than a landing gear door, Fancher says. The simplicity is a function of locating the wingtip outboard of the control surfaces, he adds.
By contrast, the folding wing mechanism proposed two decades ago for the original 777 at the request of customers was dropped because it was too complicated. Weighing 1,500kg, the previous design folded inboard of the control surfaces, requiring Boeing to include hydraulics and electrical systems at the hinge line.
Wingspan is a key element of the business case for the 777X, as it alone accounts for about half of the expected 20% reduction in fuel burn compared to the 777-300ER.
Boeing applied for a patent for such a simplified folding wingtip on 25 April, according to the database of the US Patent and Trademark office.
The 777X is expected to be launched later this year, and perhaps at the Dubai Air Show.