Summary
The FAA proposes to adopt a new airworthiness directive (AD) for certain Pilatus Aircraft Ltd. (Pilatus) Model PC-12/47E airplanes. This proposed AD was prompted by a report that, during an engine start on the ground, the airplane battery voltage dropped to a value that resulted in an avionic system shutdown. This proposed AD would require incorporating a temporary revision into the existing pilot's operating handbook (POH) for the affected airplanes to provide operators with instructions for an enhanced engine start procedure. The FAA is proposing this AD to address the unsafe condition on these products.