Airworthiness Directives; Empresa Brasileira de Aeronautica, S.A. (EMBRAER), Model

Résumé

This document proposes the adoption of a new airworthiness directive (AD) that is applicable to certain EMBRAER Model EMB-120 series airplanes. This proposal would require deactivation of certain circuit breakers, and a revision to the Airplane Flight Manual (AFM) to provide operational procedures to prevent loss of electrical power following an engine flameout. This proposal also would require modifications of the electrical system, which would terminate the requirement for the AFM revision and allow reactivation of the circuit breakers. This proposal is prompted by the issuance of mandatory continued airworthiness information by a foreign civil airworthiness authority. The actions specified by the proposed AD are intended to prevent generator overload conditions that could result in loss of electrical power and failure of certain flight and landing control systems, and to prevent power interruption to the attitude heading reference system (AHRS) that could result in the display of erroneous heading information.