Airworthiness Directives; Empresa Brasileira de Aeronautica S.A. (EMBRAER) Model EMB-120 Series Airplanes

This amendment supersedes an existing airworthiness directive (AD), applicable to all EMBRAER Model EMB-120 series airplanes, that currently requires revising the Airplane Flight Manual, installing a placard on the main instrument panel, and removing the "LIGHT-HEAVY" inflation switch of the leading edge deicing boots. This amendment continues to require those actions and adds requirements to install a low speed alarm for icing conditions, to revise the AFM, and to replace an existing placard with a placard that directs the flightcrew to activate the deicing boots whenever ice is detected by visual cues or ice detector illumination. This amendment is prompted by issuance of mandatory continuing airworthiness information by a foreign civil airworthiness authority. This action is intended to ensure that the flightcrew is provided with accurate indications of the severity of ice accretion, clear indication of unintentional airplane speed reductions in icing conditions, and appropriate procedures to prevent reduced controllability of the aircraft due to accretion of ice on the airplane.