Action
Supplemental notice of proposed rulemaking (NPRM); reopening of comment period.
Summary
We are revising an earlier proposed Airworthiness Directive (AD) for certain Airbus Model A330 series airplanes. The NPRM proposed to require revising the maintenance program or inspection program, as applicable, to incorporate certain maintenance requirements and airworthiness limitations. The NPRM was prompted by a determination that more restrictive maintenance requirements and airworthiness limitations are necessary. This action revises the NPRM by proposing to supersede AD 2007-05-12, AD 2009-18-20, and AD 2010-15-02 in addition to those ADs already identified in the NPRM, as well as to require more restrictive limitations and to add Airbus Model A330-323 airplanes to the applicability. We are proposing this supplemental NPRM (SNPRM) to address the aging effects of aircraft systems. Such aging effects could change the characteristics of those systems, which, in isolation or in combination with one or more other specific failures or events, could result in failure of certain life limited parts, which could reduce the structural integrity of the airplane or reduce the controllability of the airplane. Since these actions impose an additional burden over those proposed in the NPRM, we are reopening the comment period to allow the public the chance to comment on these proposed changes.