E7-16670. Airworthiness Directives; Airbus Model A321 Series Airplanes

AGENCY:

Federal Aviation Administration (FAA), Department of Transportation (DOT).

ACTION:

Final rule.

SUMMARY:

We are adopting a new airworthiness directive (AD) for the products listed above. This AD results from mandatory continuing airworthiness information (MCAI) originated by an aviation authority of another country to identify and correct an unsafe condition on an aviation product. The MCAI describes the unsafe condition as:

Some operators have reported wheel corrosion, mainly under the heat-shield overlap area. In some cases a circular crack initiated from a corrosion pit. When the crack is initiated under the bead seat, it does not lead to tire pressure loss, and can cause a flange separation as experienced by few operators.

This condition could result in separation of the wheel and consequent reduced controllability of the airplane. We are issuing this AD to require actions to correct the unsafe condition on these products.

DATES:

This AD becomes effective October 2, 2007.

The Director of the Federal Register approved the incorporation by reference of a certain publication listed in this AD as of October 2, 2007.

ADDRESSES:

You may examine the AD docket on the Internet at http://dms.dot.gov or in person at the U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue, SE., Washington, DC.

FOR FURTHER INFORMATION CONTACT:

Tim Dulin, Aerospace Engineer, International Branch, ANM-116, FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington 98057-3356; telephone [phone]; fax [phone].

SUPPLEMENTARY INFORMATION:

Discussion

We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 to include an AD that would apply to the specified products. That NPRM was published in the Federal Register on June 6, 2007 (72 FR 31209). That NPRM proposed to correct an unsafe condition for the specified products. The MCAI states:

Some operators have reported wheel corrosion, mainly under the heat-shield overlap area. In some cases a circular crack initiated from a corrosion pit. When the crack is initiated under the bead seat, it does not lead to tire pressure loss, and can cause a flange separation as experienced by few operators.

The unsafe condition could result in separation of the wheel and consequent reduced controllability of the airplane. The corrective action is inspecting the main landing gear (MLG) wheel assembly for discrepancies (corrosion, damage, cracks, and loose or missing heat shield spacers) and, if necessary, repair of the MLG wheel assembly. You may obtain further information by examining the MCAI in the AD docket.

Comments

We gave the public the opportunity to participate in developing this AD. We received no comments on the NPRM or on the determination of the cost to the public.

Conclusion

We reviewed the available data and determined that air safety and the public interest require adopting the AD as proposed.

Differences Between This AD and the MCAI or Service Information

We have reviewed the MCAI and related service information and, in general, agree with their substance. But we might have found it necessary to use different words from those in the MCAI to ensure the AD is clear for U.S. operators and is enforceable. In making these changes, we do not intend to differ substantively from the information provided in the MCAI and related service information.

We might also have required different actions in this AD from those in the MCAI in order to follow our FAA policies. Any such differences are highlighted in a NOTE within the AD.

Costs of Compliance

Based on the service information, we estimate that this AD affects about 34 products of U.S. registry. We also estimate that it takes about 6 work-hours per product to comply with the basic requirements of this AD. The average labor rate is $80 per work-hour. Based on these figures, we estimate the cost of the AD on U.S. operators to be $16,320, or $480 per product.

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 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 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); 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.

Examining the AD Docket

You may examine the AD docket on the Internet at http://dms.dot.gov;​; or in person at the Docket Operations office between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The AD docket contains the NPRM, the regulatory evaluation, any comments received, and other information. The street address for the Docket Operations office (telephone [phone]) is in the ADDRESSES section. Comments will be available in the AD docket shortly after receipt.

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.

§ 39.13

[Amended]

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

2007-17-14 Airbus: Amendment 39-15172. Docket No. FAA-2007-28358; Directorate Identifier 2007-NM-019-AD.

Effective Date

(a) This airworthiness directive (AD) becomes effective October 2, 2007.

Affected ADs

(b) None.

Applicability

(c) This AD applies to Airbus Model A321 series airplanes; all certified models; certificated in any category; equipped with Messier-Goodrich S.A. or Goodrich-Messier Inc., main landing gear (MLG) wheel assemblies having part number (P/N) C20500000 or P/N C20452000.

Subject

(d) Air Transport Association (ATA) of America Code 32: Landing Gear.

Reason

(e) The mandatory continuing airworthiness information (MCAI) states:

Some operators have reported wheel corrosion, mainly under the heat-shield overlap area. In some cases a circular crack initiated from a corrosion pit. When the crack is initiated under the bead seat, it does not lead to tire pressure loss, and can cause a flange separation as experienced by few operators.

This condition could result in separation of the wheel and consequent reduced controllability of the airplane. The corrective action is inspecting the MLG wheel assembly for discrepancies (corrosion, damage, cracks, and loose or missing heat shield spacers) and, if necessary, repair of the MLG wheel assembly.

Actions and Compliance

(f) Unless already done, do the following actions.

(1) At the next scheduled tire change, but no later than 6 months after the effective date of this AD: Inspect the MLG wheel assembly for discrepancies (corrosion, damage, cracks, and loose or missing heat shield spacers) in accordance with the instructions of Messier-Bugatti Special Inspection Service Bulletin C20452-32-3254, Revision 2, dated September 5, 2006. Repeat the inspection thereafter at intervals not to exceed every tire change or 6 months, whichever is earlier.

(2) If any discrepancy is found: Before further flight, repair the MLG wheel assembly in accordance with the instructions of Messier-Bugatti Special Inspection Service Bulletin C20452-32-3254, Revision 2, dated September 5, 2006.

FAA AD Differences

Note:

This AD differs from the MCAI and/or service information as follows: The MCAI specifies an imprecise compliance time for inspecting the MLG wheel assembly—i.e., “at each tire change.” This AD requires inspecting the MLG wheel assembly at the next scheduled tire change, but no later than 6 months after the effective date of the AD; and thereafter at intervals not to exceed every tire change or 6 months, whichever is earlier.

Other FAA AD Provisions

(g) The following provisions also apply to this AD:

(1) Alternative Methods of Compliance (AMOCs): The Manager, International Branch, ANM-116, Transport Airplane Directorate, FAA, has the authority to approve AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19. Send information to ATTN: Tim Dulin, Aerospace Engineer, International Branch, ANM-116, FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington 98057-3356; telephone [phone]; fax [phone]. Before using any AMOC approved in accordance with § 39.19 on any airplane to which the AMOC applies, notify the appropriate principal inspector (PI) in the FAA Flight Standards District Office (FSDO), or lacking a PI, your local FSDO.

(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.

(3) Reporting Requirements: For any reporting requirement in this AD, under the provisions of the Paperwork Reduction Act, the Office of Management and Budget (OMB) has approved the information collection requirements and has assigned OMB Control Number 2120-0056.

Related Information

(h) Refer to EASA Airworthiness Directive 2006-0328, dated October 23, 2006; and Messier-Bugatti Special Inspection Service Bulletin C20452-32-3254, Revision 2, dated September 5, 2006, for related information.

Material Incorporated by Reference

(i) You must use Messier-Bugatti Special Inspection Service Bulletin C20452-32-3254, Revision 2, dated September 5, 2006, to do the actions required by this AD, unless the AD specifies otherwise.

(1) The Director of the Federal Register approved the incorporation by reference of this service information under 5 U.S.C. 552(a) and 1 CFR part 51.

(2) For service information identified in this AD, contact Messier-Bugatti, 45 Avenue Victor Hugo—Bat. 227, Aubervilliers, France.

(3) 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 [phone], or go to: http://www.archives.gov/​federal-register/​cfr/​ibr-locations.html.

Issued in Renton, Washington, on August 14, 2007.

Stephen P. Boyd,

Acting Manager, Transport Airplane Directorate, Aircraft Certification Service.