AD 2012-06-11

We are adopting a new airworthiness directive (AD) for certain Airbus Model A321-131, -211, -212, and -231 airplanes. This AD requires a rotating probe inspection for cracking of the lower panel bore holes of the center wing box (CWB), and corrective actions if necessary. This AD was prompted by reports of incorrect installation of rib pads of the lower aft panel of the CWB due to poor clamping during drilling, and reports that metal chips trapped between panels and stiffeners could impact the fatigue life of CWB panels. We are issuing this AD to detect and correct cracking and damage in the bore holes of the rib pads of the lower forward and aft panels of the CWB which could result in reduced structural integrity of the wings.

Final rule; request for comments.

Adoption of the Amendment

Accordingly, under the authority delegated to me by the Administrator, the FAA amends 14 CFR part 39 as follows:

PART 39--AIRWORTHINESS DIRECTIVES

0 1. The authority citation for part 39 continues to read as follows:

Authority: 49 U.S.C. 106(g), 40113, 44701.

Sec. 39.13 [Amended]

0 2. The FAA amends Sec. 39.13 by adding the following new AD:

2012-06-11 Airbus: Amendment 39-16992. Docket No. FAA-2012-0294; Directorate Identifier 2011-NM-047-AD.

(a) Effective Date

This airworthiness directive (AD) becomes effective April 16, 2012.

(b) Affected ADs

None.

(c) Applicability

This AD applies to Airbus Model A321-131, -211, -212, and -231 airplanes; certificated in any category; manufacturer serial numbers 1293, 1299, 1307, 1333, 1356, and 1366.

(d) Subject

Air Transport Association (ATA) of America Code 57: Wings.

(e) Reason

This AD was prompted by reports of incorrect installation of rib pads of the lower aft panel of the center wing box (CWB) due to poor clamping during drilling, and reports that metal chips trapped between panels and stiffeners could impact the fatigue life of CWB panels. We are issuing this AD to detect and correct cracking and damage in the bore holes of the rib pads of the lower forward and aft panels of the CWB which could result in reduced structural integrity of the wings.

(f) Compliance

You are responsible for having the actions required by this AD performed within the compliance times specified, unless the actions have already been done.

(g) Rotating Probe Inspection

Before the accumulation of 24,000 total flight cycles or 40,000 total flight hours, whichever occurs first, since first flight of the airplane: Do a rotating probe inspection for cracking of the bore holes of the rib pads in the lower forward and aft panels of the CWB, in accordance with the Accomplishment Instructions of Airbus Mandatory Service Bulletin A320-57-1120, Revision 01, excluding Appendices 01 and 02, and including Appendix 03, dated November 15, 2006.

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(h) Repair of Cracking

If any cracking is found during any inspection required by paragraph (g) of this AD, before further flight, repair the crack according to a method approved by the Manager, International Branch, ANM-116, Transport Airplane Directorate, FAA, or EASA (or its delegated agent).

(i) Oversizing Bore Holes and Installing Fasteners

If no cracking is found during any inspection required by paragraph (g) of this AD, before further flight, oversize the holes to the next nominal diameter and install the rib pads with the new next nominal diameter fasteners, in accordance with the Accomplishment Instructions of Airbus Mandatory Service Bulletin A320-57-1120, Revision 01, excluding Appendices 01 and 02, and including Appendix 03, dated November 15, 2006.

(j) Other FAA AD Provisions

The following provisions also apply to this AD:
(1) Alternative Methods of Compliance (AMOCs): The Manager, ANM- 116, International Branch, Transport Airplane Directorate, FAA, has the authority to approve AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19. In accordance with 14 CFR 39.19, send your request to your principal inspector or local Flight Standards District Office, as appropriate. If sending information directly to the International Branch, send it to ATTN: Sanjay Ralhan, Aerospace Engineer, International Branch, ANM-116, Transport Airplane Directorate, FAA, 1601 Lind Avenue SW., Renton, Washington 98057-3356; telephone (425) 227-1405; fax (425) 227-1149.
Information may be emailed to: 9-ANM-116-AMOC-REQUESTS@faa.gov. Before using any approved AMOC, notify your appropriate principal inspector, or lacking a principal inspector, the manager of the local flight standards district office/certificate holding district office. The AMOC approval letter must specifically reference this AD.
(2) Airworthy Product: For any requirement in this AD to obtain corrective actions from a manufacturer or other source, use these actions if they are FAA-approved. Corrective actions are considered FAA-approved if they are approved by the State of Design Authority (or their delegated agent). You are required to assure the product is airworthy before it is returned to service.

(k) Related Information

Refer to Mandatory Continuing Airworthiness Information (MCAI) European Aviation Safety Agency (EASA) Airworthiness Directive 2011- 0035, dated March 2, 2011; and Airbus Mandatory Service Bulletin A320-57-1120, Revision 01, dated November 15, 2006; for related information.

(l) Material Incorporated by Reference

(1) You must use the following service information to do the actions required by this AD, unless the AD specifies otherwise. The Director of the Federal Register approved the incorporation by reference (IBR) of the following service information under 5 U.S.C. 552(a) and 1 CFR part 51:
(i) Airbus Mandatory Service Bulletin A320-57-1120, Revision 01, excluding Appendices 01 and 02, and including Appendix 03, dated November 15, 2006.
(2) For service information identified in this AD, contact Airbus, Airworthiness Office--EAS, 1 Rond Point Maurice Bellonte, 31707 Blagnac Cedex, France; telephone +33 5 61 93 36 96; fax +33 5 61 93 44 51; email: account.airworth-eas@airbus.com; Internet http://www.airbus.com.
(3) You may review copies of the service information at the FAA, Transport Airplane Directorate, 1601 Lind Avenue SW., Renton, Washington. For information on the availability of this material at the FAA, call 425-227-1221.
(4) You may also review copies of the service information that is incorporated by reference at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, call 202-741-6030, or go to: http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html.

Discussion

The European Aviation Safety Agency (EASA), which is the Technical Agent for the Member States of the European Community, has issued EASA Airworthiness Directive 2011-0035, dated March 2, 2011 (referred to after this as ``the MCAI''), to correct an unsafe condition for the specified products. The MCAI states:

During removal of one centre wing box (CWB) lower aft panel [due to reports of defects] during production, the following defects were found: --An excessive layer of sealant in between the lower panel and the rib pads, and --Small metal chips between the panel and rib pads.
Investigations revealed that the metal chips trapped between parts (panels and stiffeners) have a possible impact on fatigue life of CWB panels.
Consequently, cracks in the bore holes of the CWB lower panel may occur in service, thereby reducing the structural integrity of the aeroplane.
For the reasons describe above, this AD requires a special detailed [rotating probe] inspection of CWB lower panel bore holes to detect any defect [damage] or crack and,

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depending on findings, associated corrective actions.

The unsafe condition is potential cracking and damage in the bore holes of the rib pads of the lower forward and aft panels of the CWB which could result in reduced structural integrity of the wings. Required actions include a rotating probe inspection for cracking of the lower panel bore holes of the CWB, and corrective actions if necessary. The corrective actions include reinstalling new nominal fasteners or oversize fasteners. You may obtain further information by examining the MCAI in the AD docket.

Relevant Service Information

Airbus has issued Mandatory Service Bulletin A320-57-1120, Revision 01, including Appendices 01, 02, and 03, dated November 15, 2006. The actions described in this service information are intended to correct the unsafe condition identified in the MCAI.

FAA's Determination and Requirements of This AD

This product has been approved by the aviation authority of another country, and is approved for operation in the United States. Pursuant to our bilateral agreement with the State of Design Authority, we have been notified of the unsafe condition described in the MCAI and service information referenced above. We are issuing this AD because we evaluated all pertinent information and determined the unsafe condition exists and is likely to exist or develop on other products of the same type design.
There are no products of this type currently registered in the United States. However, this rule is necessary to ensure that the described unsafe condition is addressed if any of these products are placed on the U.S. Register in the future.

FAA's Determination of the Effective Date

Since there are currently no domestic operators of this product, notice and opportunity for public comment before issuing this AD are unnecessary.Comments Invited

This AD is a final rule that involves requirements affecting flight safety, and we did not precede it by notice and opportunity for public comment. We invite you to send any written relevant data, views, or arguments about this AD. Send your comments to an address listed under the ADDRESSES section. Include ``Docket No. FAA-2012-0294; Directorate Identifier 2011-NM-047-AD'' at the beginning of your comments. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of this AD. We will consider all comments received by the closing date and may amend this AD because of those comments.
We will post all comments we receive, without change, to http://www.regulations.gov, including any personal information you provide. We will also post a report summarizing each substantive verbal contact we receive about this AD.

Authority for This Rulemaking

Title 49 of the United States Code specifies the FAA's authority toissue rules on aviation safety. Subtitle I, section 106, describes the authority of the FAA Administrator. ``Subtitle VII: Aviation Programs,'' describes in more detail the scope of the Agency's authority.
We are issuing this rulemaking under the authority described in ``Subtitle VII, Part A, Subpart III, Section 44701: General requirements.'' Under that section, Congress charges the FAA with promoting safe flight of civil aircraft in air commerce by prescribing regulations for practices, methods, and procedures the Administrator finds necessary for safety in air commerce. This regulation is within the scope of that authority because it addresses an unsafe condition that is likely to exist or develop on products identified in this rulemaking action.

Regulatory Findings

We determined that this AD will not have federalism implications under Executive Order 13132. This AD will not have a substantial direct effect on the States, on the relationship between the national government and the States, or on the distribution of power and responsibilities among the various levels of government.
For the reasons discussed above, I certify that this AD:
1. Is not a ``significant regulatory action'' under Executive Order 12866;
2. Is not a ``significant rule'' under the DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979);
3. Will not affect intrastate aviation in Alaska; and
4. Will not have a significant economic impact, positive or negative, on a substantial number of small entities under the criteria of the Regulatory Flexibility Act.
We prepared a regulatory evaluation of the estimated costs to comply with this proposed AD and placed it in the AD docket.

List of Subjects in 14 CFR Part 39

Air transportation, Aircraft, Aviation safety, Incorporation by reference, Safety.