Airworthiness Directives; Dornier Model 328-100 Series Airplanes

This amendment adopts a new airworthiness directive (AD), applicable to certain Dornier Model 328-100 series airplanes that requires replacement of the de-icing system timer with a new, improved timer. This amendment is prompted by reports of possible overheating and debonding of the propeller blade due to a failure of the de-icing system timer and a dormant short circuit in the propeller de-icer system. The actions specified by this AD are intended to prevent such overheating and debonding of the propeller blade, which could result in reduced controllability of the airplane.