AD 2007-06-02

The FAA is superseding an existing airworthiness directive (AD), which applies to all Airbus Model A318-100 and A319-100 series airplanes, Model A320-111 airplanes, and Model A320-200, A321-100, and A321-200 series airplanes. That AD currently requires repetitive inspections of the upper and lower attachments of the trimmable horizontal stabilizer actuator (THSA) to measure for proper clearance and to detect cracks, damage, and metallic particles. The existing AD also requires corrective actions, if necessary, and reports of inspection findings. This new AD shortens the repetitive interval for inspecting the upper THSA attachment. This AD results from new test results on the secondary load path, which indicated the need to shorten the repetitive interval for inspecting the upper THSA attachment. We are issuing this AD to detect and correct failure of the THSA's primary load path, which could result in latent (undetected) loading and eventual failure of the THSA's secondary load path and consequent uncontrolled movement of the horizontal stabilizer and loss of control of the airplane.

DATES: This AD becomes effective April 19, 2007.

The Director of the Federal Register approved the incorporation by reference of Airbus Service Bulletin A320-27-1164, Revision 04, including Appendix 01, dated July 17, 2006, as of April 19, 2007.

On May 5, 2006 (71 FR 16203, March 31, 2006), the Director of the Federal Register approved the incorporation by reference of Airbus Service Bulletin A320-27-1164, Revision 03, including Appendix 01, dated August 24, 2005.

Final rule.

2007-06-02 Airbus: Amendment 39-14983. Docket No. FAA-2006-26516; Directorate Identifier 2006-NM-173-AD.

Effective Date

(a) This AD becomes effective April 19, 2007.

Affected ADs

(b) This AD supersedes AD 2006-07-09.

Applicability

(c) This AD applies to all Airbus Model A318, A319, A320, and A321 airplanes, certificated in any category.

Unsafe Condition

(d) This AD results from new test results on the secondary load path, which indicated the need to shorten the repetitive interval for inspecting the upper attachment of the trimmable horizontal stabilizer actuator (THSA). We are issuing this AD to detect and correct failure of the THSA's primary load path, which could result in latent (undetected) loading and eventual failure of the THSA's secondary load path and consequent uncontrolled movement of the horizontal stabilizer and loss of control of the airplane.

Compliance

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

Note 1: For the purposes of this AD, a detailed inspection is: "An intensive examination of a specific item, installation, or assembly to detect damage, failure, or irregularity. Available lighting is normally supplemented with a direct source of good lighting at an intensity deemed appropriate. Inspection aids such as mirror, magnifying lenses, etc., may be necessary. Surface cleaning and elaborate procedures may be required.''

Repetitive Inspections: Lower THSA Attachment

(f) Within 20 months since first flight of the airplane, or within 600 flight hours after May 5, 2006 (the effective date of AD 2006-07-09), whichever occurs later: Do detailed inspections of the lower THSA attachments for proper clearances, and do related corrective actions as applicable, in accordance with the Accomplishment Instructions of Airbus Service Bulletin A320-27-1164, Revision 03, including Appendix 01,dated August 24, 2005; or Revision 04, including Appendix 01, dated July 17, 2006. After the effective date of this AD, only Revision 04 of the service bulletin may be used. Do corrective actions before further flight. Repeat the inspection thereafter at intervals not to exceed 20 months.

Repetitive Inspections: Upper THSA Attachment

(g) At the earlier of the times specified in paragraphs (g)(1) and (g)(2) of this AD: Do detailed inspections of the upper THSA attachment for cracks, damage, or metallic particles, and do related corrective actions as applicable, in accordance with the Accomplishment Instructions of Airbus Service Bulletin A320-27-1164, Revision 04, including Appendix 01, dated July 17, 2006, except as required by paragraph (h) of this AD. Do corrective actions before further flight. Repeat the inspections thereafter at intervals not to exceed 10 months.

(1) At the latest of the times specified in paragraphs (g)(1)(i), (g)(1)(ii), and (g)(1)(iii) of this AD.

(i) Within 10 months since the first flight of the airplane.

(ii) Within 10 months after the most recent inspection of the upper THSA attachment done in accordance with Airbus Service Bulletin A320-27-1164, Revision 02, including Appendix 01, dated March 30, 2005; Revision 03, including Appendix 01, dated August 24, 2005; or Revision 04, including Appendix 01, dated July 17, 2006.

(iii) Within 100 days after the effective date of this AD.

(2) Within 20 months after the most recent inspection of the upper THSA attachment done in accordance with Airbus Service Bulletin A320-27-1164, Revision 02, including Appendix 01, dated March 30, 2005; Revision 03, including Appendix 01, dated August 24, 2005; or Revision 04, including Appendix 01, dated July 17, 2006.

Repair Exceptions

(h) If any metallic particles are detected during any inspection required by paragraph (g) of this AD: Repair the damage before further flight in accordance with a method approved by theManager, International Branch, ANM-116, Transport Airplane Directorate, FAA; the Direction Generale de l'Aviation Civile (DGAC) (or its delegated agent); or the European Aviation Safety Agency (EASA) (or its delegated agent).

Acceptable Prior Actions

(i) Inspections of the lower THSA attachment done before May 5, 2006, in accordance with Airbus Alert Service Bulletin A320-27A1164, dated September 10, 2004; or Airbus Service Bulletin A320-27-1164, Revision 01, including Appendix 01, dated December 17, 2004; are acceptable for compliance with the inspection requirements of paragraph (f) of this AD.

(j) Actions done before the effective date of this AD in accordance with Airbus Service Bulletin A320-27-1164, Revision 02, including Appendix 01, dated March 30, 2005; or Revision 03, including Appendix 01, dated August 24, 2005; are acceptable for compliance with the corresponding requirements of paragraphs (f) and (g) of this AD.

Inspection Reports

(k) At the applicable time specified in paragraph (k)(1) or (k)(2) of this AD, send a report of the positive findings of all inspections required by paragraphs (f) and (g) of this AD to Airbus, 1 Rond Point Maurice Bellonte, 31707 Blagnac Cedex, France. The report must include the inspection results, a description of any discrepancies found, the airplane serial number, and the number of landings and flight hours on the airplane. Using Appendix 01 of Airbus Service Bulletin A320-27-1164, Revision 02, dated March 30, 2005; Revision 03, dated August 24, 2005; or Revision 04, dated July 17, 2006; is an acceptable method to comply with this paragraph. Under the provisions of the Paperwork Reduction Act (44 U.S.C. 3501 et seq.), the Office of Management and Budget (OMB) has approved the information collection requirements contained in this AD and has assigned OMB Control Number 2120-0056.

(1) For any inspection done before the effective date of this AD: Send the report within 30 days after the effective date of this AD.

(2) For any inspection done after the effective date of this AD: Send the report within 30 days after the inspection.

Alternative Methods of Compliance (AMOCs)

(l)(1) The Manager, International Branch, ANM-116, has the authority to approve AMOCs for this AD, if requested in accordance with the procedures found in 14 CFR 39.19.

(2) Before using any AMOC approved in accordance with Sec. 39.19 on any airplane to which the AMOC applies, notify the appropriate principal inspector in the FAA Flight Standards Certificate Holding District Office.

Related Information

(m) EASA airworthiness directive 2006-0223, dated July 21, 2006, also addresses the subject of this AD.

Material Incorporated by Reference

(n) You must use Airbus Service Bulletin A320-27-1164, Revision 03, including Appendix 01, dated August 24, 2005; or Airbus Service Bulletin A320-27-1164, Revision 04, including Appendix 01, dated July 17, 2006; as applicable; to perform the actions that are required by this AD, unless the AD specifies otherwise.

(1) The Director of the Federal Register approved the incorporation by reference of Airbus Service Bulletin A320-27-1164, Revision 04, including Appendix 01, dated July 17, 2006, in accordance with 5 U.S.C. 552(a) and 1 CFR part 51.

(2) On May 5, 2006 (71 FR 16203, March 31, 2006), the Director of the Federal Register approved the incorporation by reference of Airbus Service Bulletin A320-27-1164, Revision 03, including Appendix 01, dated August 24, 2005.

(3) Contact Airbus, 1 Rond Point Maurice Bellonte, 31707 Blagnac Cedex, France, for a copy of this service information. You may review copies at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or 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/cfr/ibr-locations.html .

Examining the Docket

You may examine the airworthiness directive (AD) docket on the Internet at http://dms.dot.gov or in person at the Docket Management Facility office between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The Docket Management Facility office (telephone (800) 647-5227) is located on the plaza level of the Nassif Building at the street address stated in the ADDRESSES section.

Discussion

The FAA issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 to include an AD that supersedes AD 2006-07-09, amendment 39-14536 (71 FR 16203, March 31, 2006). The existing AD applies to all Airbus Model A318-100 and A319-100 series airplanes, Model A320-111 airplanes, and Model A320-200, A321-100, and A321-200 series airplanes. That NPRM was published in the Federal Register on December 8, 2006 (71 FR 71103). That NPRM proposed to continue to require the existing actions (repetitive inspections of the upper and lower attachments of the trimmable horizontal stabilizer actuator (THSA) to measure for proper clearance and to detect cracks, damage, and metallic particles; corrective actions, if necessary; and reports of inspection findings). That NPRM proposed to shorten the repetitive interval for inspecting the upper THSA attachment.

Comments

We provided the public the opportunity to participate in the development of this AD. We have considered the comments that have been received on the NPRM.

Request To Extend Repetitive Interval

The NPRM proposed to reduce the existing repetitive interval for inspecting the upper attachment--from 20 months to 10 months. Agreeing with the intent of the AD, Northwest Airlines nonetheless requests that we change this inspection interval to 11 months. The commenter reports that Northwest Airlines' inspection of 139 affected airplanes during accomplishment of AD 2006-07-09 has revealed no findings. Northwest Airlines is currently working with Airbus to better understand the reasons for the reduced inspection interval for the upper attachment. Northwest Airlines' current L-check interval is 21.5 months. The commenter therefore feels that an inspection interval of 11 months for the upper attachment would allow Northwest Airlines to accomplish alternate inspections in a hangar, and yet fulfill the intent of the AD. The commenter explains that a hangar environment would allow the use of a more effective, specialized workforce, and reduce the impact of correcting any finding.

We disagree with the request to extend the compliance time. The absence of positive findings alone does not justify an extension of the compliance time in this case. The 10-month inspection interval for the upper attachment is based on the results of Airbus's tests of the endurance of the secondary load path under simulated loads. Northwest Airlines did not provide any data that would support the extension of the compliance time. We have not changedthe final rule.

Conclusion

We have carefully reviewed the available data, including the comments that have been submitted, and determined that air safety and the public interest require adopting the AD as proposed.

Costs of Compliance

The following table provides the estimated costs for U.S. operators to comply with this AD, per inspection cycle.

Estimated Costs

Work hours
Average labor rate per hour
Parts
Cost per airplane
Number of U.S.-registered airplanes
Fleet cost
1
$80
None
$80
700
$56,000

Authority for This Rulemaking

Title 49 of the United States Code specifies the FAA's authority to issue 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 have 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 DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); and

(3) 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 AD and placed it in the AD docket. See the ADDRESSES section for a location to examine the regulatory evaluation.

List of Subjects in 14 CFR Part 39

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

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

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]

2. The Federal Aviation Administration (FAA) amends Sec. 39.13 by removing amendment 39-14536 (71 FR 16203, March 31, 2006) and by adding the following new airworthiness directive (AD):