Summary
We propose to adopt a new airworthiness directive (AD) for the products listed above. This proposed AD results from mandatory continuing airworthiness information (MCAI) originated by an aviation authority of another country to identify and correct an unsafe condition on an aviation product. The MCAI describes the unsafe condition as:
Further to initial qualification tests of the spoiler actuators currently installed in position No. 3 to 7 on A300-600 and A300- 600ST aircraft fleet, a life limit [of 55,750 flight hours] has been defined by the actuator manufacturer. Initially, this life limit had no repercussions, as it was situated well beyond the initial Design Service Goal (DSG) of the aircraft. However, due to the Extended Service Goal (ESG) activities, the spoiler actuator life limit can be reached in service, and therefore the spoiler actuators must be replaced before exceeding this limit. In order to mitigate the risk to have aircraft on which the three hydraulic circuits would be impacted by affected spoiler actuators, which could result in the loss of controllability of the aircraft, this Airworthiness Directive (AD) requires actions to ensure that at least the level of safety of one hydraulic circuit will be restored within an acceptable timeframe. * * * * *
The proposed AD would require actions that are intended to address the unsafe condition described in the MCAI.