AD FAA-2013-0791

We are adopting a new airworthiness directive (AD) for all Airbus Model A318, A319, A320, and A321 series airplanes. This AD was prompted by a report that an investigation showed that when a certain combination of a target/proximity sensor serial number is installed on a flap interconnecting strut, a "target FAR" signal cannot be detected when it reaches the mechanical end stop of the interconnecting strut. This AD requires an inspection to determine the part number of the interconnecting struts installed on the wings, identifying the part number and the serial number of the associated target and proximity sensor if applicable, and replacing or re-identifying the flap interconnecting strut if applicable. We are issuing this AD to detect and correct a latent failure of the flap down drive disconnection due to an already-failed interconnecting strut sensor, which could result in asymmetric flap panel movement and consequent loss of control of the airplane.