Airworthiness Directives; Airbus Airplanes

We propose to adopt a new airworthiness directive (AD) for all Airbus Model A318, A319, A320, and A321 series airplanes. This proposed AD was prompted by reports of airspeed indication discrepancies while flying at high altitudes in inclement weather. This proposed AD would require replacing certain pitot probes on the captain, first officer, and standby sides with certain new pitot probes. We are proposing this AD to prevent airspeed indication discrepancies during inclement weather, which, depending on the prevailing altitude, could lead to unknown accumulation of ice crystals and consequent reduced controllability of the airplane.