Summary
The FAA proposes to adopt a new airworthiness directive (AD) for certain Pilatus Aircraft Ltd. (Pilatus) Model PC-12, PC-12/45, PC- 12/47, and PC-12/47E airplanes. This proposed AD was prompted by mandatory continuing airworthiness information (MCAI) originated by an aviation authority of another country to identify and correct an unsafe condition on an aviation product. The MCAI identifies the unsafe condition as insufficient grounding of the vapor cycle cooling system (VCCS) compressor/condenser. This proposed AD would require inspecting the power return and chassis grounding cable attachment points at frame 37, including the attachment parts, and depending on the inspection results, corrective action. This proposed AD would also require modifying the installation of the VCCS compressor/condenser power return cables and installing an additional isolated VCCS chassis ground cable. The FAA is proposing this AD to address the unsafe condition on these products.