[Federal Register Volume 72, Number 108 (Wednesday, June 6, 2007)]
[Proposed Rules]
[Pages 31209-31211]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: E7-10865]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2007-28358; Directorate Identifier 2007-NM-019-AD]
RIN 2120-AA64


Airworthiness Directives; Airbus Model A321 Series Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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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:

    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 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 July 6, 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: (202) 493-2251.
     Mail: Docket Management Facility, U.S. Department of 
Transportation, 400 Seventh Street, SW., Nassif Building, Room PL-401, 
Washington, DC 20590-0001.
     Hand Delivery: Room PL-401 on the plaza level of the 
Nassif Building, 400 Seventh Street, SW., 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 Management Facility 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 Office (telephone (800) 647-5227) 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 (425) 
227-2141; fax (425) 227-1149.

SUPPLEMENTARY INFORMATION: 

Streamlined Issuance of AD

    The FAA is implementing a new process for streamlining the issuance 
of ADs related to MCAI. This streamlined process will allow us to adopt 
MCAI safety requirements in a more efficient manner and will reduce 
safety risks to the public. This process continues to follow all FAA AD 
issuance processes to meet legal, economic, Administrative Procedure 
Act, and Federal Register requirements. We also continue to meet our 
technical decision-making responsibilities to identify and correct 
unsafe conditions on U.S.-certificated products.
    This proposed AD references the MCAI and related service 
information that we considered in forming the engineering basis to 
correct the unsafe condition. The proposed AD contains text copied from 
the MCAI and for this reason might not follow our plain language 
principles.

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-
28358; Directorate Identifier 2007-NM-019-AD'' at the beginning of your 
comments. We specifically invite

[[Page 31210]]

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 2006-0328, dated October 23, 2006 (referred to 
after this as ``the MCAI''), 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 MCAI mandates 
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.

Relevant Service Information

    Messier-Bugatti has issued Special Inspection Service Bulletin 
C20452-32-3254, Revision 2, dated September 5, 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 34 products of U.S. registry. We also estimate that 
it would take about 6 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 $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 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.


Sec.  39.13  [Amended]

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

Airbus: Docket No. FAA-2007-28358; Directorate Identifier 2007-NM-
019-AD.

Comments Due Date

    (a) We must receive comments by July 6, 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) 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 MCAI

[[Page 31211]]

mandates 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 would require 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, 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, 
98057-3356, telephone (425) 227-2141; fax (425) 227-1149. 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.
    (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.

    Issued in Renton, Washington, on May 25, 2007.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. E7-10865 Filed 6-5-07; 8:45 am]
BILLING CODE 4910-13-P