Action
Final rule.
Summary
We are superseding two existing airworthiness directives (AD). One existing AD is for Airbus Model A319, A320, and A321 series airplanes without Airbus modification 26017. That AD currently requires replacing the flight warning computers (FWCs). The other existing AD is for Airbus Model A320 and A321 series airplanes on which Airbus modification 24612 or Airbus Service Bulletin A320-31-1080 has not been accomplished. That existing AD currently requires revising the limitations section of the airplane flight manual. This new AD requires replacing both FWC units with certain FWC units. This AD was prompted by in-service events of thrust lever mismanagement and a manufacturer analysis on the failure to follow procedure or heed existing cockpit cues. The analysis of the thrust lever management issue showed two categories of scenarios that could lead to thrust asymmetry during landing, with controllability and deceleration consequences. We are issuing this AD to prevent thrust asymmetry conditions which could result in loss of control of the airplane during landing.