AD 98-07-18 63 FR 16678

This amendment adopts a new airworthiness directive (AD) that applies to certain Pilatus Aircraft Ltd. (Pilatus) Models PC-12 and PC- 12/45 airplanes. This AD requires replacing certain propeller de-icing controllers with ones that are not susceptible to electromagnetic interference (EMI). This AD is the result of mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for Switzerland. The actions specified by this AD are intended to prevent improper operation of the propeller de-icing controller caused by EMI, which could result in ice build-up on the propeller with possible airplane controllability problems.