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

This amendment supersedes an existing airworthiness directive (AD), applicable to all Airbus Model A310 and A300-600 series airplanes, that currently requires a revision to the Airplane Flight Manual (AFM) that warns the flight crew of certain consequences associated with overriding the autopilot when it is in the pitch control axis. That AD also requires modification of certain flight control computers (FCC). That AD was prompted by the results of an FAA review of the requirements of an earlier AD. This amendment requires a modification to the autopilot that would enable the flight crew to disconnect the autopilot when direct force is applied to the control column, regardless of its mode and the altitude of the airplane; accomplishment of that modification terminates the current requirement to revise the AFM. This amendment also requires repetitive operational testing of the modified autopilot to determine if the disconnect function operates properly, and repair, if necessary. The actions specified by this AD are intended to prevent an out-of-trim condition between the trimmable horizontal stabilizer and the elevator, which could severely reduce controllability of the airplane.