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

This amendment supersedes an existing airworthiness directive (AD), applicable to certain Airbus Model A300, A310, A300-600 series airplanes, that currently requires a one-time operational test and repetitive functional tests of the free fall control mechanism of the landing gear to ensure proper release of the main landing gear (MLG), and corrective action, if necessary. It also requires eventual modification of the free fall control mechanism of the landing gear, which constitutes terminating action for the repetitive functional tests. This amendment requires, for certain airplanes, that the modification of the free fall control mechanism of the landing gear be accomplished in accordance with a corrected version of the manufacturer's service bulletin. 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 malfunction of the free fall control mechanism of the landing gear, which could result in the inability to extend the MLG in the event of failure of the hydraulic extension system.