Action
Final rule.
Summary
We are superseding Airworthiness Directive (AD) 2016-01-11, which applied to certain Airbus Model A320-211, -212, and -231 airplanes. AD 2016-01-11 required repetitive inspections for cracking of the radius of the front spar vertical stringers and the horizontal floor beam on frame (FR) 36, repetitive inspections for cracking of the fastener holes of the front spar vertical stringers on FR 36, and repair if necessary. This AD adds new thresholds and intervals for the repetitive inspections; requires, for certain airplanes, a potential terminating action modification of the center wing box area; and expands the applicability. This AD was prompted by a report that, during a center fuselage certification full-scale fatigue test, cracks were found on the front spar vertical stringer at a certain frame. This AD was also prompted by a determination that, during further investigations of the frame as part of the widespread fatigue damage (WFD) campaign, certain inspection compliance times have to be revised and new inspections and a new potential terminating action modification have to be introduced. We are issuing this AD to address the unsafe condition on these products.