Airworthiness Directives; Airbus Model A310, A300-600, and A320 Series Airplanes

This amendment supersedes an existing airworthiness directive (AD), applicable to certain Airbus Model A310, A300-600, and A320 series airplanes, that currently requires inspections to verify proper installation of the grill over the air extraction duct of the lavatory and to detect blockages in the air extraction duct of the lavatory, and correction of any discrepancies. This amendment adds a requirement for modification of the grill of the air extraction duct, which, when accomplished, terminates the repetitive inspections. This amendment also expands the applicability of the existing AD to include additional airplanes. 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 obstructions in the air extraction system of the lavatory, which may result in the failure of the smoke detection system to detect smoke in the lavatories.