Airworthiness Directives; Pilatus Aircraft Ltd. Airplanes

The FAA proposes to supersede Airworthiness Directive (AD) 2023-26-05, which applies to certain Pilatus Aircraft Ltd. (Pilatus) Model PC-24 airplanes. AD 2023-26-05 requires periodic replacement of affected titanium threaded bolts, a one-time inspection of the rudder mass balance arm and other elements of the rudder trim tab installation for correct attachment, damage (gouges), cracks, deformation, surface finish, and corrosion on any surrounding parts and, depending on findings, the accomplishment of applicable corrective actions. Since the FAA issued AD 2023-26-05, it was determined that some batches of titanium bolts had variations in the microstructure that could affect the fatigue characteristics. This proposed AD would require replacing affected short rudder-trim control rod assemblies with serviceable rudder-trim control rod assemblies having threaded steel bolts and would prohibit the installation of affected parts, 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.