Airworthiness Directives; Jetstream Model ATP Airplanes

This amendment adopts a new airworthiness directive (AD), applicable to certain Jetstream Model ATP airplanes, that requires installation of modified engine de-ice timers, modification of the electrical wiring for the duct heat of the engine air intake, and installation of a time delay for the de-ice system in the air intake duct of the right engine. This amendment also requires associated revisions to the Airplane Flight Manual. This amendment is prompted by reports of ice that accreted in the engine air intake ducts and was ingested into the engine; this resulted in engine power rollback (loss of engine power). The actions specified by this AD are intended to prevent loss of multiple engine power during flight in icing conditions.