Airworthiness Directives; Airbus Model A330 and A340 Airplanes

The FAA is superseding an existing airworthiness directive (AD), which applies to certain Airbus Model A330-200, A330-300, A340- 200, and A340-300 series airplanes; and Model A340-541 and -642 airplanes. That AD currently requires repetitively resetting the display units (DUs) for the electronic instrument system (EIS), either by switching them off and back on again or by performing a complete electrical shutdown of the airplane. This new AD requires installing new software, which would end the actions required by the existing AD. This new AD also adds additional airplanes that may be placed on the U.S. Register in the future. This AD results from an incident in which all of the DUs for the EIS went blank simultaneously during flight. We are issuing this AD to prevent automatic reset of the DUs for the EIS during flight and consequent loss of data from the DUs, which could reduce the ability of the flightcrew to control the airplane during adverse flight conditions.