Special requirements for Boeing's folding wings
Washington - The retractable wing tips of the Boeing 777X are a novelty in civil aviation. Now, the US aviation authority has explained what it requires for certification.
FAA asks Boeing all power sources that could enable unlocking must be automatically disconnected from the wing tip's operating and locking system prior to take-off and not be reconnected during the flight.
In October, Boeing launched the production of the first civil jet with retractable wing tips. The 777X reduces its span by folding it from 72 to 65 meters to avoid getting into trouble with its long wings at airports. The US Federal Aviation Administration (FAA) has now identified a number of requirements as part of the certification of the new technology to ensure that Boeing meets all safety standards.
The FAA requires the US aircraft manufacturer, among others, a warning function that sounds the alarm in several ways to warn pilots before taxiing in unsecured areas and notify them when the wingtips are collapsed during taxiing. In addition, it must be ensured that the takeoff is prevented if the tips are not secured or are not in their correct position.
Boeing also must demonstrate that the aircraft is manageable when it collapses the wing tips in the crosswind after landing. And the most important, The company must ensure that the deployed wings can not unlock during flight by mistake. Therefore, the FAA requirement is that all power sources that could enable unlocking must be automatically disconnected from the wing tip's operating and locking system prior to take-off and not be reconnected during the flight.
Boeing said that the conditions are not uncommon and no surprise after four years of consulting with US and European regulators. It has therefore developed the appropriate functions to meet all special requirements. The certification of the two X models 777-8 and 777-9 runs in the context of a modified certification of the normal 777.