AD 2007-25-12

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: After a push back from the gate, an A320-200 aircraft was preparing to initiate taxi, when a NLG (nose landing gear) uncommanded retraction occurred, and then the aircraft abruptly hit the ground. * * * Untimely unlocking and/or retraction of the NLG, while on the ground, could cause injury to ground personnel and significant structural damage to the airplane. We are issuing this AD to require actions to correct the unsafe condition on these products.

Final rule.

2007-25-12 Airbus: Amendment 39-15294. Docket No. FAA-2007-29249; Directorate Identifier 2007-NM-112-AD.

Effective Date

(a) This Airworthiness Directive (AD) becomes effective January 14, 2008.

Affected ADs

(b) None.

Applicability
(c) This AD applies to Airbus Model A318, A319, A320, and A321 series airplanes, certificated in any category, except those identified in paragraph (c)(1) or (c)(2) of this AD.

(1) Manufacturer serial numbers (MSNs) 2389, 2392, 2393, 2396, 2398, 2403, 2405, 2407, 2409, 2410, 2411, 2413 through 2439, 2441, and MSNs above 2441, on which no replacement of the landing gear (LG) selector valve 40GA or the LG door selector valve 41GA has been performed since aircraft delivery from Airbus.

(2) Aircraft on which LG selector valve 40GA and LG door selector valve 41GA have been stamped to indicate that a duplicate inspection has been done. If the duplicate inspection has been done, the amendment plates on the valves will be stamped with letters "DI'' or "DI-BE.''

Subject

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

Reason

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

"After push back from the gate, an A320-200 aircraft was preparing to initiate taxi, when an NLG (nose landing gear) uncommanded retraction occurred, and then the aircraft abruptly hit the ground. Investigations revealed that the retract condition is caused by a combination of a faulty MLG (main landing gear) proximity switch, a power interruption to LGCIUs (Landing Gear Control and Interface Units) and an internal hydraulic leak through the LG (landing gear) selector valve 40GA. The internal hydraulic leak through the LG selector valve 40GA was due to a broken seal in one of the end cap chambers for the valve spool. As a corrective action, a duplicate inspection (DI or DI-BE) for these valves has been introduced in production, and the Component Maintenance Manual (CMM) has been revised. Untimely unlocking and/or retraction of the NLG, while on the ground, could cause injury to ground personnel and significant structural damage to the aircraft.

This Airworthiness Directive (AD) mandates the inspections of the LG selector valve 40GA and the LG door selector valve 41GA, to identify a possible hydraulic leak.''

The corrective action includes replacing the LG selector valve 40GA and/or the LG door selector valve 41GA if necessary.

Actions and Compliance

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

(1) For aircraft that have accumulated up to and including 20,000 total flight cycles as of the effective date of this AD: Within 4,500 flight cycles after the effective date of this AD, but not exceeding 20,800 total flight cycles, inspect for hydraulic leaking of the LG selector valve 40GA and the LG door selector valve 41GA and, as applicable, replace the LG selector valve 40GA and the LG door selector valve 41GA before further flight in accordance with the Accomplishment Instructions of Airbus Service Bulletin A320-32- 1290, Revision 01, dated November 10, 2006.

(2) For aircraft that have accumulated over 20,000 total flight cycles as of the effective date of this AD: Within 800 flight cycles after the effective date of this AD, inspect for hydraulic leaking of the LG selector valve 40GA and the LG door selector valve 41GA and, as applicable, replace the LG selector valve 40GA and the LG door selector valve 41GA before further flight in accordance with the Accomplishment Instructions of Airbus Service Bulletin A320-32-1290, Revision 01, dated November 10, 2006.

(3) For all airplanes: Repeat the inspection specified in paragraph (f)(1) or (f)(2) of this AD, as applicable, thereafter at intervals not to exceed 20,000 flight cycles, or 89 months, whichever occurs first, and, as applicable, (i.e., if any leakage is found) replace the LG selector valve 40GA and the LG door selector valve 41GA before further flight,in accordance with the Accomplishment Instructions of Airbus Service Bulletin A320-32-1290, Revision 01, dated November 10, 2006.

(4) For all airplanes: From the effective date of this AD, the installation of LG selector valve 40GA or LG door selector valve 41GA, that do not have the duplicate inspection "DI'' or "DI-BE'' recorded on their amendment plates, is possible provided that it is inspected within 800 flight cycles after installation, in accordance with the instructions given in Airbus Service Bulletin A320-32-1290, Revision 01, dated November 10, 2006. Repeat the inspection thereafter as given in paragraph (f)(3) of this AD.

(5) Actions done before the effective date of this AD in accordance with Airbus Service Bulletin A320-32-1290, dated May 2, 2006, are acceptable for compliance with the corresponding actions of this AD.

FAA AD Differences

Note: This AD differs from the MCAI and/or service information as follows: No differences.

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 (425) 227-2141; fax (425) 227-1149. Before using any approved AMOC on any airplane to which the AMOC applies, notify your 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 MCAI EASA Airworthiness Directive 2007-0065R1, dated June 12, 2007, and Airbus Service Bulletin A320-32-1290, Revision 01, dated November 10, 2006, for related information.

Material Incorporated by Reference

(i) You must use Airbus Service Bulletin A320-32-1290, Revision 01, excluding Appendix 01, dated November 10, 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 Airbus, 1 Rond Point Maurice Bellonte, 31707 Blagnac Cedex, 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 (202) 741-6030, or go to: http://www.archives.gov/federal-register/cfr/ibr-locations.html .

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 September 20, 2007 (72 FR 53699). That NPRM proposed to correct an unsafe condition for the specified products. The MCAI states:

After push back from the gate, an A320-200 aircraft was preparing to initiate taxi, when a NLG (nose landing gear) uncommanded retraction occurred, and then the aircraft abruptly hit the ground. Investigations revealed that the retract condition is caused by a combination of a faulty MLG (main landing gear) proximity switch, a power interruption to LGCIUs (Landing Gear Control and Interface Units) and an internal hydraulic leak through the LG (landing gear) selector valve 40GA. The internal hydraulic leak through the LG selector valve 40GA was due to a broken seal in one of the end cap chambers for the valve spool. As a corrective action, a duplicate inspection (DI or DI-BE) for these valves has been introduced in production, and the Component Maintenance Manual (CMM) has been revised. Untimely unlocking and/or retraction of the NLG, while on the ground, could cause injury to ground personnel and significant structural damage to the aircraft.

This Airworthiness Directive (AD) mandates the inspections of the LG selector valve 40GA and the LG door selector valve 41GA, to identify a possible hydraulic leak.

The corrective action includes replacing the LG selector valve 40GA and/or the LG door selector valve 41GA if necessary. 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.

Editorial Change

We have revised paragraphs (f)(1), (f)(2), and (f)(3) of this AD by removing the phrase "if necessary''and adding the phrase "as applicable,'' in order to clarify that the replacement must be done if leaking is found.

Conclusion

We reviewed the available data and determined that air safety and the public interest require adopting the AD with the changes described previously. We determined that these changes will not increase the economic burden on any operator or increase the scope of the AD.

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

We estimate that this AD will affect about 653 products of U.S. registry. We also estimate that it will take about 7 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 this AD to the U.S. operators to be $365,680, or $560 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://www.regulations.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 (800) 647-5527) 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.

Sec. 39.13 [Amended]

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

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