Airworthiness Directives; Empresa Brasileira de Aeronautica, S.A. (EMBRAER), Model EMB-145 Series Airplanes

This amendment supersedes an existing airworthiness directive (AD), applicable to all Empresa Brasileira de Aeronautica, S.A. (EMBRAER), Model EMB-145 series airplanes, that currently requires repetitive emergency extension (free-fall) functional tests of the nose landing gear (NLG), and lubrication of all NLG hinge points, to ensure that the NLG extends and locks down properly; and corrective action, if necessary. This amendment also requires a terminating modification that includes replacement of the NLG door solenoid valve with an improved valve; replacement of the landing gear (LG) safety pins holder with an improved holder; and replacement of the NLG maneuvering actuator with an improved actuator. This amendment also limits the applicability of the existing AD. This amendment is prompted by issuance of mandatory continuing airworthiness information by a foreign civil airworthiness authority. The actions specified by this AD are intended to prevent failure of the NLG to extend and lock down properly, which could result in damage to the airplane structure, and consequent reduced controllability of the airplane upon landing.