Action
Notice of proposed rulemaking (NPRM).
Summary
The FAA proposes to supersede Airworthiness Directive (AD) 2020-18-04, which applies to all Airbus SAS Model A350-941 and -1041 airplanes. AD 2020-18-04 requires a one-time health check of the slat power control unit (PCU) torque sensing unit (TSU), a detailed inspection of the slat transmission systems, corrective actions if necessary, and track 12 slat gear rotary actuator (SGRA) water drainage and vent plug cleaning. Since the FAA issued AD 2020-18-04, it has been determined that the one-time health check must be repetitive instead to monitor the TSU wear, and that the water drainage and vent plug cleaning is no longer required. This proposed AD would require repetitive health checks of the slat PCU TSU, a detailed visual inspection of the slat transmission systems, and corrective actions if necessary; as specified in a European Union Aviation Safety Agency (EASA) AD, which is proposed for incorporation by reference. The FAA is proposing this AD to address the unsafe condition on these products.