In a first for commercial aviation, the latest version of Boeing’s 777 jet will have partial retractable wings.
Boeing said the 777X design will expand the wingspan to 235 feet, which significantly improves fuel efficiency.
The retractable wingtip feature allows planes to use airport gates which cannot accommodate the extended wingspans.
On landing the wings will retract to a maximum 212 feet, allowing them to use existing gates.
The FAA has tentatively approved the design.
"These airplanes will have a novel or unusual design feature when compared to the state of technology envisioned in the airworthiness standards for transport-category airplanes. This design feature is folding wingtips," the FAA said in its report.
Folding wings have been used on military aircraft before but this is the first time they have been designed for a commercial airliner.
