Summary
We propose to supersede Airworthiness Directive (AD) 2014-14- 06 for all Airbus Model A318-111 and -112 airplanes; Model A319-111, - 112, -113, -114, and -115 airplanes; Model A320-111, -211, -212, and - 214 airplanes; and Model A321-111, -112, -211, -212, and -213 airplanes. AD 2014-14-06 currently requires inspecting the aft engine mount retainers for surface finish, cracks, and failure, and replacement if necessary. Since we issued AD 2014-14-06, inspection results have shown that the main cause of crack initiation remains the vibration dynamic effect that affects both retainers, either with ``dull'' or ``bright'' surface finishes. This proposed AD would require repetitive inspections for damage, cracks, broken, and missing aft engine mount retainers, and replacement if necessary. We are proposing this AD to detect and correct failure of retainer brackets of the aft engine mount and consequent loss of the locking feature of the nuts of the inner and outer pins; loss of thepins will result in the aft mount engine link no longer being secured to the aft engine mount.