E7-18540. Airworthiness Directives; Airbus Model A318, A319, A320, and A321 Series Airplanes

AGENCY:

Federal Aviation Administration (FAA), DOT.

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

We propose to adopt a new airworthiness directive (AD) for the products listed above. This proposed 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.

The proposed AD would require actions that are intended to address the unsafe condition described in the MCAI.

DATES:

We must receive comments on this proposed AD by October 22, 2007.

ADDRESSES:

You may send comments by any of the following methods:

• DOT Docket Web Site: Go to http://dms.dot.gov and follow the instructions for sending your comments electronically.
• Fax: [phone].
• Mail: U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue, SE., Washington, DC 20590.
• Hand Delivery: Room W12-140 on the ground floor of the West Building, 1200 New Jersey Avenue, SE., Washington, DC, between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays.
• Federal eRulemaking Portal: http://www.regulations.gov. Follow the instructions for submitting comments.

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 this proposed AD, 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.

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:

Comments Invited

We invite you to send any written relevant data, views, or arguments about this proposed AD. Send your comments to an address listed under the ADDRESSES section. Include “Docket No. FAA-2007-29249; Directorate Identifier 2007-NM-112-AD” at the beginning of your comments. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of this proposed AD. We will consider all comments received by the closing date and may amend this proposed AD based on those comments.

We will post all comments we receive, without change, to http://dms.dot.gov, including any personal information you provide. We will also post a report summarizing each substantive verbal contact we receive about this proposed AD.

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 2007-0065R1, dated June 12, 2007 (referred to after this as “the MCAI”), 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.

Relevant Service Information

Airbus has issued Service Bulletin A320-32-1290, Revision 01, dated November 10, 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 Proposed 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 proposing this AD because we evaluated all pertinent information and determined an unsafe condition exists and is likely to exist or develop on other products of the same type design.

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 proposed different actions in this AD from those in the MCAI in order to follow FAA policies. Any such differences are highlighted in a NOTE within the proposed AD.

Costs of Compliance

Based on the service information, we estimate that this proposed AD would affect about 653 products of U.S. registry. We also estimate that it would take about 7 work-hours per product to comply with the basic requirements of this proposed AD. The average labor rate is $80 per work-hour. Based on these figures, we estimate the cost of the proposed AD on 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 proposed AD would not have federalism implications under Executive Order 13132. This proposed AD would 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 proposed regulation:

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 proposed AD and placed it in the AD docket.

List of Subjects in 14 CFR Part 39

• Air transportation
• Aircraft
• Aviation safety
• Safety

The Proposed Amendment

Accordingly, under the authority delegated to me by the Administrator, the FAA proposes to amend 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:

Airbus: Docket No. FAA-2007-29249; Directorate Identifier 2007-NM-112-AD.

Comments Due Date

(a) We must receive comments by October 22, 2007.

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 paragraphs (c)(1) and (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 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.

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 replace if necessary 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 replace if necessary 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 replace if necessary (i.e., if any leakage is found) 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, Transport Airplane Directorate, ANM-116, 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 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.

Issued in Renton, Washington, on September 10, 2007.

Ali Bahrami,

Manager, Transport Airplane Directorate, Aircraft Certification Service.