Action
Supplemental notice of proposed rulemaking (NPRM); reopening of comment period.
Summary
We are revising an earlier proposed airworthiness directive (AD) for all Airbus Model A318 series airplanes, Airbus Model A319 series airplanes, Airbus Model A320 series airplanes, and Airbus Model A321 series airplanes. That NPRM proposed an inspection to determine if certain angle of attack (AOA) probes are installed, and replacing the affected AOA probe if necessary. That NPRM was prompted by reports of oil residue between the stator and the rotor parts of the position resolvers of the AOA vane, which was a result of incorrect removal of the machining oil during the manufacturing process of the AOA resolvers. This action revises that NPRM by including an inspection to determine if certain other AOA probes are installed, and replacing the affected probes. We are proposing this AD to prevent erroneous AOA information and consequent delayed or non-activation of the AOA protection systems which, during flight at a high angle of attack, could result in reduced control of the airplane. Since these actions impose an additional burden over that proposed in the NPRM, we are reopening the comment period to allow the public the chance to comment on these proposed changes.