On May 18, the Federal Aviation Administration (FAA) approved the design for Boeing’s folding CFRP wingtips that will be incorporated the company two 777X aircraft variants, the 777-8 and 777-9. The technology is expected to help the company comply with the FAA’s airport gate code. Boeing will incorporate this on-ground wingtip-fold capability to reduce the wingspan from 235 to 212 feet when folded.

The FAA approval for the wingtips came as Boeing is already assembling the first wings for the new models. Back in October, Boeing officially kicked off wing production at its Composite Wing Center in Everett, Wash. The 777X features a lightweight wing design based on a composite spar made of over 400 miles of carbon tape cured in a specially built autoclave. Toray’s TORAYCA® prepreg is being used for these main wings. When finished, the 777’s new wing will be the company’s widest, passing the 747-8.

One of the conditions the FAA imposed is that Boeing must have multiple automatic warning systems to ensure pilots won’t ever try lifting off without the wingtips fully extended. The agency also said Boeing must demonstrate that the wingtips could never be accidentally unlocked during flight and that “no force or torque can unlatch or unlock the mechanisms.” The wings must also be able to withstand wind gusts as high as 75 miles an hour on the ground.

Boeing is confident assembly of wings for the initial batch of ground and flight test 777Xs will be completed on schedule despite delays and production challenges. According to Boeing, the 777-9 variant will still fly in the first quarter of 2019 with deliveries to begin in December 2019.