Airworthiness Directives; Airbus Model A310-200 and -300 Series Airplanes

The FAA is adopting a new airworthiness directive (AD) for certain Airbus Model A310-200 and -300 series airplanes. This AD requires repetitive inspections for cracking of the flap transmission shafts, and replacing the transmission shafts if necessary. This AD also provides an optional terminating action for the repetitive inspections. This AD results from reports of longitudinal cracks due to stress corrosion in the transmission shafts between the power control unit (PCU) and the torque limiters of the flap transmission system. We are issuing this AD to detect and correct cracking of the flap transmission shaft, which could compromise shaft structural integrity and lead to a disabled flap transmission shaft and reduced controllability of the airplane.