Airworthiness Directives; Pilatus Aircraft Ltd. Models PC-6, PC-6-H1, PC-6-H2, PC-6/350, PC-6/350-H1, PC-6/350-H2, PC-6/A, PC-6/A-H1, PC-6/A-H2, PC-6/B-H2, PC-6/B1-H2, PC-6/B2-H2, PC-6/B2-H4, PC-6/C-H2, and PC-6/C1-H2 Airplanes

The FAA adopts a new airworthiness directive (AD) for all Pilatus Aircraft Ltd. (Pilatus) (also identified as Fairchild Republic Company and Fairchild Heli Porter) Model PC-6 airplanes. This AD requires you to repetitively inspect the stabilizer-trim attachment and structural components for cracks, corrosion, and discrepancies and replace any defective part with a new part. This AD also requires you to replace all Fairchild connecting pieces, part number (P/N) 6232.0026.XX, with a Pilatus connecting piece and requires you to replace fittings without an index after the P/N with an improved part. This AD results from mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for Switzerland. We are issuing this AD to detect and correct defective stabilizer-trim attachments and surrounding structural components, which could result in failure of the stabilizer-trim attachment. This failure could lead to loss of control of the airplane.