On 8 August, Boeing demonstrated the folding wingtip on its Boeing 777-9 (N779XW) test aircraft during a ground test. The new feature is the first of its kind on a commercial aircraft reducing the wingspan from 72 meters to 65 meters, allowing the aircraft to fit at airport gates.
The Federal Aviation Administration (FAA) had to make new arrangements in the regulations before approving the design as Boeing had to prove that no force or torque in the air can unlock the extended wingtips.
The new wing has a higher lift-to-drag ratio, an aspect ratio increased from 9:1 to 10:1, an area increased from 4,702 to 5,562 sq ft (436.8 to 516.7 m2), and usable fuel capacity increased from 320,863 to 350,410 lb (145,541 to 158,943 kg).
Nine companies already bought the aircraft type, with Lufthansa as the launch customer. Boeing already recorded 325 firm orders of the Boeing 777X model.
Source: wikipedia Boeing 777X (English)