Summary
The FAA proposes to adopt a new airworthiness directive (AD) for all Airbus SAS Model A350-941 and -1041 airplanes. This proposed AD was prompted by a report of inadvertent auto flight system (AFS) altitude changes on the flight control unit (FCU). This proposed AD would require revising the existing airplane flight manual (AFM) to include a procedure on the use of the AFS control panel ALT knob and replacing any affected FCU with a serviceable FCU, as specified in a European Union Aviation Safety Agency (EASA), which is proposed for incorporation by reference. This proposed AD would also prohibit the installation of affected parts. The FAA is proposing this AD to address the unsafe condition on these products.